tag:blogger.com,1999:blog-23699796882097959622024-03-12T23:03:22.985+01:00Neuroradiology On the NetA isointense on T1-WI blogDavidhttp://www.blogger.com/profile/04879167223808984022noreply@blogger.comBlogger558125tag:blogger.com,1999:blog-2369979688209795962.post-64216170712578728352011-03-14T16:00:00.000+01:002011-03-14T22:48:16.514+01:00Band heterotopia<span style="font-style:italic;">CASE 1 (7-month-old)</span><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHR35lEyqPeQxsN2GgkLVU9r3G2JdNwq_WwdqruBNiKrE8PVdO8ibWrw6vfICc7ad6YSHaBYcYq8sh95GUEVikV3nJjJGNv6OUUAD9vCuolvmSW_nfwEngVa0Gg8SCNa4Ycde8Jc-Fj38/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHR35lEyqPeQxsN2GgkLVU9r3G2JdNwq_WwdqruBNiKrE8PVdO8ibWrw6vfICc7ad6YSHaBYcYq8sh95GUEVikV3nJjJGNv6OUUAD9vCuolvmSW_nfwEngVa0Gg8SCNa4Ycde8Jc-Fj38/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5584054644364377778" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGZpq1V5PKIRyFGolYfn3zWFgi8B9GuRiG6i4FIpv7cgirRUwLeHVDeAHqlA-2tBe22SylVzt2HvqW_puN1xQXx_QNcciis4CFF1U_4Tf2jV08LIYnM4C9EyYjdraxFr3ofASFbmfOJWo/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGZpq1V5PKIRyFGolYfn3zWFgi8B9GuRiG6i4FIpv7cgirRUwLeHVDeAHqlA-2tBe22SylVzt2HvqW_puN1xQXx_QNcciis4CFF1U_4Tf2jV08LIYnM4C9EyYjdraxFr3ofASFbmfOJWo/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5584054603348639954" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjS1U_8yeCxjiTN-cyt6f7qH4AHCmj0GV5QK1R6LA23eMKiPnmOQqaaJTkU8fyDysUiffJ6To2HQrKQKNbefFeW6WZLhau-qy5Qyb9Bv45Hc-SlXeiI3xCTYDxZRLEnN3Z6mWp3GbhT38Y/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjS1U_8yeCxjiTN-cyt6f7qH4AHCmj0GV5QK1R6LA23eMKiPnmOQqaaJTkU8fyDysUiffJ6To2HQrKQKNbefFeW6WZLhau-qy5Qyb9Bv45Hc-SlXeiI3xCTYDxZRLEnN3Z6mWp3GbhT38Y/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5584054565662077250" /></a><br /><br /><br /><span style="font-style:italic;">CASE 2 (Pre-adolescent)</span><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEizz5EM0xtbqCliMDY7PmVzliCKWh-aKDXGV2K9EUlVSWPac3g3n5AaPJ6uKVDoL5Vv3vTjyDZth3uwqnGwGayUVTpPmk0QjxOUouXDH-KlSKRDh68cRiP9PQ58lnADdl3Q-aXa1fWXWts/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEizz5EM0xtbqCliMDY7PmVzliCKWh-aKDXGV2K9EUlVSWPac3g3n5AaPJ6uKVDoL5Vv3vTjyDZth3uwqnGwGayUVTpPmk0QjxOUouXDH-KlSKRDh68cRiP9PQ58lnADdl3Q-aXa1fWXWts/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5584054492536902034" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmDh9TY1q5PGPgYM_gKFzTez3WbyTpwbaiHkyO7vrNykAMuD6-r2czVOg84yF0bERx6BDE_UhfSBeijwxiN71IgxLnE_BASK7S-LvYF5apLkF7qkvqp01gt9VHZGCT4pFALHr-fWOTPcE/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmDh9TY1q5PGPgYM_gKFzTez3WbyTpwbaiHkyO7vrNykAMuD6-r2czVOg84yF0bERx6BDE_UhfSBeijwxiN71IgxLnE_BASK7S-LvYF5apLkF7qkvqp01gt9VHZGCT4pFALHr-fWOTPcE/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5584054438455751410" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzYJ5kTf4XBasQWvXJb6sWbW0XE2TQiSltuaUP4CPSuYmTsh-Q3Xxb1LF_lNyVjQH2ZnYkCScMBp7kwkVvLGw14aRXBu6ZnhBMW_W8fCAVTzgTEfYai0B5gmXlg1bQOOVLWYvt6kE5Gc8/s1600/6.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 256px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjzYJ5kTf4XBasQWvXJb6sWbW0XE2TQiSltuaUP4CPSuYmTsh-Q3Xxb1LF_lNyVjQH2ZnYkCScMBp7kwkVvLGw14aRXBu6ZnhBMW_W8fCAVTzgTEfYai0B5gmXlg1bQOOVLWYvt6kE5Gc8/s400/6.ashx"border="0"alt=""id="BLOGGER_PHOTO_ID_5584054382524692642" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Case 1: Axial and coronal T2-weighted images of the brain in a 7-month-old girl with seizures demonstrate a band of isointense signal within the subcortical white matter, characteristic of band heterotopia.<br />Case 2: Axial and coronal T1-weighted images demonstrate band heterotopia, better seen in this preadolescent girl due to completion of myelination.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Band heterotopia</span><br /><br /><br />Band heterotopia is a rare neuronal migration anomaly which manifests as homogenous bands of gray matter are interposed between the lateral ventricles and cortical mantle with normal appearing white matter on either side. The overlying cortex may be normal, pachygyric, or display a simplified gyral pattern with short gyri and shallow sulci. At least six morphologically distinct subtypes have been described. Band heterotopias represent a subset of gray matter heterotopia which also includes subependymal and subcortical heterotopia subtypes.<br /><br />Band heterotopia typically affects female patients as a result of an X-linked dominant inheritance pattern secondary to abnormal function of the doublecortin (DCX) gene (Xp22.3-p23) or less frequently the LIS1 (17p13.3) gene. Male patients can be affected due to sporadic mutations of these genes (41 reported cases in the literature by D’Agostino, et al in 2002). The rate of detectable mutations involving DCX or LIS1 in male patients (42%) is lower than the rate of 85% described in female patients. Dysmorphic features described in patients with band heterotopia include microcephaly (most common), wide nasal bridge, high arched palate, and short stature.<br /><br />The clinical presentation of band heterotopia can range from normal to nearly normal intelligence and mild developmental delay to frank mental retardation. Seizures are often also present and may begin in the first decade, ranging from partial to generalized or multiple seizure types. The discovery of the underlying brain malformation is due to the onset of seizures in 65% of patients. Eventually 95% of patients with band heterotopias will develop epilepsy. Seizures associated with band heterotopia are often refractory to medical therapy, and surgical therapies such as callosotomy may be performed in these patients. In the series of 30 male patients published in 2002, 46% of patients were refractory to medical therapy and experienced up to 20-30 seizures daily despite trails of multiple therapeutic regimens. Affected male patients tend to have either mild or severe symptoms, whereas, female patients tend to have symptoms within the mild to moderate range of the spectrum from minimal cognitive impairment to severe mental retardation. Posterior involvement, in particular the partial posterior and intermediate posterior subtypes, occur more commonly in male patients. Frontal and diffuse subtypes are more often present in affected female patients.Unknownnoreply@blogger.com39tag:blogger.com,1999:blog-2369979688209795962.post-49231799055850682252011-03-07T16:00:00.000+01:002011-03-08T13:47:34.488+01:00Chloroma of epidural space<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUJ-veDvbqfRbgzJEdj9nTQ-1raSL_1bePrEopRoUIIVFXIiaMgX3jeJeTjaWWJYpCgNEqw51tOXBtMc3fs_h0wQMO2Aawiib_uR4z8ZkSj3_N05wUJULj6zqZY8d8Q5Gwh45hpODdmIE/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUJ-veDvbqfRbgzJEdj9nTQ-1raSL_1bePrEopRoUIIVFXIiaMgX3jeJeTjaWWJYpCgNEqw51tOXBtMc3fs_h0wQMO2Aawiib_uR4z8ZkSj3_N05wUJULj6zqZY8d8Q5Gwh45hpODdmIE/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5581688812654120930" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj62hY-sxwpwP6pYl4SaJM7RodkXMoov8v518pJt8H2yPXYmVzCBnVH94Vx5Nfmg_Qc5VnfgYTtk8QYkhEAWmg5aYpHmrCypXl4tTHprR9NQCh2aaD6w7U4Xv9C_vh-N2DbProEmY8XkLE/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 383px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj62hY-sxwpwP6pYl4SaJM7RodkXMoov8v518pJt8H2yPXYmVzCBnVH94Vx5Nfmg_Qc5VnfgYTtk8QYkhEAWmg5aYpHmrCypXl4tTHprR9NQCh2aaD6w7U4Xv9C_vh-N2DbProEmY8XkLE/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5581688715068363538" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9Td0zAv3zhOefrIKs7B5d_tye_1ROJ3AahyNTVyKNehMPa8_pzrEskn9flLs4ZJ2KMREUfp60J5Y2ceKqxd7Evc7k1_R91ybrzKg3-GmOUAGBlefYuA-lIZqAjtEtay_s7uhfsPi6VfI/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 383px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9Td0zAv3zhOefrIKs7B5d_tye_1ROJ3AahyNTVyKNehMPa8_pzrEskn9flLs4ZJ2KMREUfp60J5Y2ceKqxd7Evc7k1_R91ybrzKg3-GmOUAGBlefYuA-lIZqAjtEtay_s7uhfsPi6VfI/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5581688654293808754" /></a><br />Additional clinical history: Acute leukemia.<br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Large anterior epidural mass extending from posterior clinoid to the cervicothoracic junction measuring approx. 6x3x1.5 cm with mass effect on the anterior pons, medulla, and upper cervical cord. No post-contrast imaging obtained.<br /><br />Differential diagnosis: Epidural mass<br />- Metastatic disease<br />- Lymphoma<br />- Leukemia/chloroma<br />- Chordoma<br />- Osteomyelitis/epidural abscess<br />- Epidural hematoma<br />- Primary tumor such as neurofibroma/schwannoma<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Chloroma of epidural space</span><br /><br /><br /><span style="font-style:italic;">Key points</span> <br /><br />AKA granulocytic sarcoma, extramedullary myeloblastoma.<br />Most commonly occurs in the setting of AML.<br />Can also occur in setting of chronic myelogenous leukemia and other myeloproliferative disorders.<br />These tumors can involve any part of the body, either concurrently or sequentially.<br /><br />Imaging characteristics:<br />- NECT: Isodense or hyper dense to brain or muscle<br />- MR: Hypo intense or Iso intense on T1-weighted MR images, heterogeneously Iso intense or hyper intense on T2-weighted MR images<br />- MR+C: Enhance homogeneously after injection of contrast medium<br /><br />Paraspinal and intraspinal lesions are also thought to arise from perivenous arachnoid spread of leukemic cells. Uncommonly, spinal involvement by granulocytic sarcoma may cause compression of the spinal cord, cauda equina, or nerve rootsUnknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-35580064544624457302011-03-01T16:00:00.009+01:002011-03-01T17:47:37.373+01:00Basilar dolichoectasia determining a vascular loop compression syndrome<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRA_QHp6x-PZqU2XFf8snDBIjXe0DHp2YIwFhYOh8Jkcl6vjkcCRQOd1gh4Uh_Hz1Kie70E85YxFeW-XxWJyR-BCN5MtVN594xdwwuNLGzqLabff5sBTo3sjqKGKeLRQfsobV6H2WNfqg/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 357px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRA_QHp6x-PZqU2XFf8snDBIjXe0DHp2YIwFhYOh8Jkcl6vjkcCRQOd1gh4Uh_Hz1Kie70E85YxFeW-XxWJyR-BCN5MtVN594xdwwuNLGzqLabff5sBTo3sjqKGKeLRQfsobV6H2WNfqg/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579153191964227906" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjal4xWmLBuGQkTcU-32xk-o5LrFYdWfrSQiiM9g1wxEw-4STf9j257iUcg232ZfnTpG5hVEqcpPCqvbLcVot8wAr6Wg2jDDfw48TZnMjwv-L9_Usv2ZPzrIA9pE-w16Gv2OLaDr5qUKR0/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 390px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjal4xWmLBuGQkTcU-32xk-o5LrFYdWfrSQiiM9g1wxEw-4STf9j257iUcg232ZfnTpG5hVEqcpPCqvbLcVot8wAr6Wg2jDDfw48TZnMjwv-L9_Usv2ZPzrIA9pE-w16Gv2OLaDr5qUKR0/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579153139859793186" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaM84nxpeVckmlMEp63r5yfah3in-moCRVZVRz1_0d4s7NNpysUwTSfLkWfOTC8a7OBuDWOJbZntNIgsgDfhzi_Mt-jZ-N1iIy9acawH34BQIO24JmfPQJgd2fcku2MfhCrdv2f0HcB1I/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 395px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhaM84nxpeVckmlMEp63r5yfah3in-moCRVZVRz1_0d4s7NNpysUwTSfLkWfOTC8a7OBuDWOJbZntNIgsgDfhzi_Mt-jZ-N1iIy9acawH34BQIO24JmfPQJgd2fcku2MfhCrdv2f0HcB1I/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579152846218390690" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhijAffqmpzb53kAGK2SZk-hzb7KCjUaOJfCvY6nJau9VvFt4wIiyrp9n1xdRR9DQt8K9cT2XAh6H4jOUQmsQ1LgJld_SU0uUU-nuu-mYE-cG0AgSV4azJAnoX_KTtygbzVjIwpXy1CvGY/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 396px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhijAffqmpzb53kAGK2SZk-hzb7KCjUaOJfCvY6nJau9VvFt4wIiyrp9n1xdRR9DQt8K9cT2XAh6H4jOUQmsQ1LgJld_SU0uUU-nuu-mYE-cG0AgSV4azJAnoX_KTtygbzVjIwpXy1CvGY/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579152789909048722" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRLzIOOZhRw-lu8OVHR1Aua-t9FNyr7Y__gLRj15h73YXsBAmQ_2TX_ojiOeWUvsFfms1_e621s3ev8Ap0I-dQILFoOXBEtlnByx0IZ3nZensOSOdia7pC_rP5TuqCikXB5EHWl3tLNUQ/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 399px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRLzIOOZhRw-lu8OVHR1Aua-t9FNyr7Y__gLRj15h73YXsBAmQ_2TX_ojiOeWUvsFfms1_e621s3ev8Ap0I-dQILFoOXBEtlnByx0IZ3nZensOSOdia7pC_rP5TuqCikXB5EHWl3tLNUQ/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579152728788436482" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgqx2TbExsXMB0Y39IawXeeHdGeGLiaqrenD3fTTzW2V8GL3vdRmVtW8kgBz_47VSL1q0darO8wi25bVOMVLqh-g0Ph6D1TaWC27fTAxpYMnH4hQkEQXBFyIxLK3cIQM7k4P1LxcYcRkFw/s1600/6.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 398px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgqx2TbExsXMB0Y39IawXeeHdGeGLiaqrenD3fTTzW2V8GL3vdRmVtW8kgBz_47VSL1q0darO8wi25bVOMVLqh-g0Ph6D1TaWC27fTAxpYMnH4hQkEQXBFyIxLK3cIQM7k4P1LxcYcRkFw/s400/6.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5579152641239092642" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1, Figure 2, Figure 3, Figure 4, and Figure 5: Axial high resolution T2 fiesta images show a dilated and tortuous basilar artery which extends into the left cerebellopontine angle. The visualized inner ear structures are normal.<br />Figure 6: The basilar artery appears to contact the left trigeminal nerve at the root-exit zone.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Basilar dolichoectasia</span><br /><br /><br />Trigeminal neuralgia is a clinical syndrome composed of paroxysmal facial pain usually confined to the maxillary (V2) and/or mandibular (V3) branches of the trigeminal nerve. Occasionally the opthalmic division (V1) is also affected. This syndrome is more common in patients over the age of 65, with no gender specificity.<br /><br />VLCS is a recognized cause of trigeminal neuralgia. The offending vessel courses into the anterior cerebellopontine cistern with subsequent irritation of the 5th cranial nerve at the preganglionic root entry zone (REnZ). Additional causes of trigeminal neuralgia include anuersysms, AVMs, and tumors of the cerebello-pontine angle. Demyelinating disorders such as multiple sclerosis are also described as a potential cause.<br /><br />Thin section high resolution T2 MRI of the CPA/IAC allows the best visualization of the vascular loop. These images also show the anatomic course of the 5th cranial nerve from the root entry zone into meckel’s cave. The imaging protocol should include whole brain T2/FLAIR to exclude additional etiologies such as multiple sclerosis. Axial and coronal T1 of the brainstem with gadolinium enhancement is also helpful to look for cranial neuritis, perineural tumor, and cisternal tumor such as an epidermoid, schwanomma, or meningioma.Unknownnoreply@blogger.com1tag:blogger.com,1999:blog-2369979688209795962.post-2058067154913646202011-02-23T16:00:00.001+01:002011-02-26T14:54:49.594+01:00Lateral medullary syndrome (Wallenberg syndrome)<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivCMzNA-FXN0fqAbOlcEJ4BsbFbunbg5T6M4NMu_Kgp8ppzfCh6id8XG1fL1sOrJd5aMN_MDl_lNPQ0ES8i0jTp6dlV-TLJPVqSp18okoAgzuDaDmfT0PZ4fRvQRUZ_w31rWjSOZPZatU/s1600/5.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 335px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivCMzNA-FXN0fqAbOlcEJ4BsbFbunbg5T6M4NMu_Kgp8ppzfCh6id8XG1fL1sOrJd5aMN_MDl_lNPQ0ES8i0jTp6dlV-TLJPVqSp18okoAgzuDaDmfT0PZ4fRvQRUZ_w31rWjSOZPZatU/s400/5.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993779162609666" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-I1tkA50f0K8ZK0wtdJ-1dmi8vDW5bT0ETzsM-sRHtk81W4bAJRZsGMJQfD8jIveH-Wy-Z_H_xT7Xy0it-OU4TSu2eHGl4sJDO18qowtEI_6N366K3ErSIu36Qxh3Wyi-1ccAKoGdbJg/s1600/6.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 312px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-I1tkA50f0K8ZK0wtdJ-1dmi8vDW5bT0ETzsM-sRHtk81W4bAJRZsGMJQfD8jIveH-Wy-Z_H_xT7Xy0it-OU4TSu2eHGl4sJDO18qowtEI_6N366K3ErSIu36Qxh3Wyi-1ccAKoGdbJg/s400/6.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993723549443042" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgmVX0_1cwAI-adV7wdI0sn6t5Zk0NueoZQIli0GaCgPiAkweDSzfqqMPpwpC4RIKcH8yGdQTj1mCeamwbuDM4Hhyphenhyphen2SWiAT_iqnJE-YPwfIt8J-VV10azLnuPVEd9SkIVPrpa-2Q3cWu1I/s1600/7.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 325px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgmVX0_1cwAI-adV7wdI0sn6t5Zk0NueoZQIli0GaCgPiAkweDSzfqqMPpwpC4RIKcH8yGdQTj1mCeamwbuDM4Hhyphenhyphen2SWiAT_iqnJE-YPwfIt8J-VV10azLnuPVEd9SkIVPrpa-2Q3cWu1I/s400/7.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993658442234962" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgByuSQ1ZimBQOWwuaboJMo2a4vkzDlCmVTaVO8MT0bAgPSOrAIe75tv7xpjWa0toTKjKdHFqjLS79qYoZE5BSuckFafKTJmEVGPjWDHzKtG7P8jEqt3gUJ905GKsTtAmAnKU4f17yw2ns/s1600/8.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 321px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgByuSQ1ZimBQOWwuaboJMo2a4vkzDlCmVTaVO8MT0bAgPSOrAIe75tv7xpjWa0toTKjKdHFqjLS79qYoZE5BSuckFafKTJmEVGPjWDHzKtG7P8jEqt3gUJ905GKsTtAmAnKU4f17yw2ns/s400/8.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993596506204674" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgS-XacC9iG9007hQXSqjVLJj3rkzfzsx_Uc9fHFT06FVMALyk_OfagN5Rpni5Hilr1QV7eeefCBxMdW4eT2mia0JyzdPOleTWxgDs9J0K6RmUq4AuKqfNV9n4DR5vlUL6MoZwq8hOWho/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 291px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgS-XacC9iG9007hQXSqjVLJj3rkzfzsx_Uc9fHFT06FVMALyk_OfagN5Rpni5Hilr1QV7eeefCBxMdW4eT2mia0JyzdPOleTWxgDs9J0K6RmUq4AuKqfNV9n4DR5vlUL6MoZwq8hOWho/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993528962917442" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi26iq6KK4mmkxYVw6HiCZNhLqPs_-2rwEk8TFGECwaXf5mJgHfBRvWBQv7UNnO1ZMgDI0_57HyoMarbbba7YO1__58ZzePuPD6009qwNm71mrt9enaM29PnLtEQ-nYlRWTOSXsWGkS76A/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 309px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi26iq6KK4mmkxYVw6HiCZNhLqPs_-2rwEk8TFGECwaXf5mJgHfBRvWBQv7UNnO1ZMgDI0_57HyoMarbbba7YO1__58ZzePuPD6009qwNm71mrt9enaM29PnLtEQ-nYlRWTOSXsWGkS76A/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993490198749538" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjq3RxbWMK3HJwcM0FYRPpwPBXNJwCYbek-CTmQwqjQYk2pRHZ8XXSN0qxQtEyKxcNVwRgKShYLi6I4gOaPOhGPxMQ8ZKOP5SiC18C5DT7a2wmS6y9sTObD92T-Owo0nGBlFs50YV-Av0E/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 308px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjq3RxbWMK3HJwcM0FYRPpwPBXNJwCYbek-CTmQwqjQYk2pRHZ8XXSN0qxQtEyKxcNVwRgKShYLi6I4gOaPOhGPxMQ8ZKOP5SiC18C5DT7a2wmS6y9sTObD92T-Owo0nGBlFs50YV-Av0E/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993439832749138" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIfSOg_94kdRSjy0t2NZWV0ZfEotlo34VFBxonbsrIBb1PAYXP9r6uc15CXhgETxFd4KHkVmHsAPPHuOt-ey05UYn2OqHefJyZRQgDvCTSOO6Z69JLFM1GxYhgPfX1UaVaQOSWPVQfHM8/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 339px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIfSOg_94kdRSjy0t2NZWV0ZfEotlo34VFBxonbsrIBb1PAYXP9r6uc15CXhgETxFd4KHkVmHsAPPHuOt-ey05UYn2OqHefJyZRQgDvCTSOO6Z69JLFM1GxYhgPfX1UaVaQOSWPVQfHM8/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993384157867330" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhEsx7ytPJBJRZFleGE0-5L9D-fxzV5bG4DMRHeyMTpxBMWmWaKRpPNdTJnjvu5HD8e4NrkmT90ELjom8HLfjd4a9vhSFxVWZlw5M9OACDuIsKtR9K2Ep2AYzA-ict-KGIAqhQ_Jp0C38w/s1600/9.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 381px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhEsx7ytPJBJRZFleGE0-5L9D-fxzV5bG4DMRHeyMTpxBMWmWaKRpPNdTJnjvu5HD8e4NrkmT90ELjom8HLfjd4a9vhSFxVWZlw5M9OACDuIsKtR9K2Ep2AYzA-ict-KGIAqhQ_Jp0C38w/s400/9.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577993303518602754" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Axial FLAIR (Figure 1 and Figure 2) and T2-weighted (Figure 3 and Figure 4) images demonstrate mild signal hyperintensity in region of the left lateral and posterior medulla PICA territory.<br />Axial DWI (Figure 5 and Figure 6) and matching ADC maps (Figure 7 and Figure 8) demonstrate true restricted diffusion in the left lateral and posterior medulla PICA suggestive of cytotoxic edema fort an acute infarction.<br />3D TOF posterior circulation MIP projection (Figure 9) demonstrates absence of a normal left PICA. It's possibile to see the right PICA for comparison, arising from the distal right intracranial vertebral artery. There is also a mild narrowing of the basilar artery. It's possibile also to appreciate bith the superior cerebellar arteries.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Lateral medullary syndrome (Wallenberg syndrome)</span><br /><br /><br />Adolf Wallenberg (November 10, 1862-1949) was a German internist and neurologist who first described the clinical manifestations (1895) and the autopsy findings (1901) in occlusions of the arteria cerebelli posterior inferior (Wallenberg syndrome).<br /><br />Lateral medullary syndrome is characterized by sensory deficits affecting the trunk and extremities on the opposite side of the infarct and sensory, and motor deficits affecting the face and cranial nerves on the same side with the infarct. Other clinical symptoms and findings include ataxia, facial pain, vertigo, nystagmus, diplopia, Horner syndrome, and dysphagia. The cause of this syndrome is secondary to occlusion of the PICA near its origin. Similar symptoms may be produced by vertebral artery occlusion near the origin of the PICA.<br /><br />Afflicted persons can have dysphagia resulting from involvement of the nucleus ambiguus and slurred speech (dysphonia and dysarthria). Damage to the spinal trigeminal nucleus causes absence of pain on the ipsilateral side of the face as well as an absent corneal reflex. The spinothalamic tract can be damaged, resulting in loss of pain and temperature sensation to the opposite side of the body. Damage to the cerebellum can cause ataxia. Damage to the hypothalamospinal fibers disrupts sympathetic nervous system relay and gives symptoms analogous to Horner syndrome (ptosis, anhidrosis, and miosis).<br /><br />In older patients, the most common cause of posterior circulation ischemia is thromboembolic disease resulting from accelerated atheromatous disease or embolic disease from a cardiac source. In young patients with posterior fossa ischemia, in addition to embolic disease, the diagnosis of arterial dissection should also be considered.<br />Wallenberg syndrome synonyms: dorsolateral medullary syndrome, lateral bulbar syndrome, lateral medullary infarction syndrome, and PICA syndrome.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-42215653202789185182011-02-08T16:00:00.001+01:002011-02-25T18:20:15.213+01:00Subdural empyema<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_j75c5f1Sn0xdkt3yJtzWqSoMuk2AUTcT36V-73fSNVmblqo_KirqJRswPw8xMgCNkf_nnmWgTWRAagMSyA_Amk-Kw3JaIkjauNWQTqPszyzu2MG8Euq-8cfYw0NiJi0YCHdX4-is_fs/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 330px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_j75c5f1Sn0xdkt3yJtzWqSoMuk2AUTcT36V-73fSNVmblqo_KirqJRswPw8xMgCNkf_nnmWgTWRAagMSyA_Amk-Kw3JaIkjauNWQTqPszyzu2MG8Euq-8cfYw0NiJi0YCHdX4-is_fs/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577677650817164050" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglXIF_p34pjGjO5-1ONSjUaok9vjihJ1oQ1_DaoJbDwhWFzXQdJARo7hEUhIQCv8JEMabHOk8aw5CV2Az4YCJi43j3dRMKZQ5s8Rruk_jZnY6Uyr1GvCeCyGrXiYBClFs3zMxZyS2mpQo/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 326px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglXIF_p34pjGjO5-1ONSjUaok9vjihJ1oQ1_DaoJbDwhWFzXQdJARo7hEUhIQCv8JEMabHOk8aw5CV2Az4YCJi43j3dRMKZQ5s8Rruk_jZnY6Uyr1GvCeCyGrXiYBClFs3zMxZyS2mpQo/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577677578943458754" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJdKWV2cgr5TekanInnL86m5ofiZWX4KDiXf8ckBjHKqS1rEaAAwev6Zw3v_7dO4TKxvbV181hye_UxTCBibsbvQYsImnJW7t_IE15H5GmVMstE5Pm0iWfgNtGZVKMNee1XC8b36tVFOQ/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 319px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJdKWV2cgr5TekanInnL86m5ofiZWX4KDiXf8ckBjHKqS1rEaAAwev6Zw3v_7dO4TKxvbV181hye_UxTCBibsbvQYsImnJW7t_IE15H5GmVMstE5Pm0iWfgNtGZVKMNee1XC8b36tVFOQ/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577677508667022338" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrfEPPkkkh2gw2bVHDI7opZQ-slhgWlTq_GSq2Dbg20La7BHUfIHYgVTTIIPtrXDZE_bXirRM23n_cNbiKRbv9jyP-vvYeVo4RH-_zfPClWovXKuTtDl4QiwwnaW_LQ6-MFqBapzSIYys/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 318px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrfEPPkkkh2gw2bVHDI7opZQ-slhgWlTq_GSq2Dbg20La7BHUfIHYgVTTIIPtrXDZE_bXirRM23n_cNbiKRbv9jyP-vvYeVo4RH-_zfPClWovXKuTtDl4QiwwnaW_LQ6-MFqBapzSIYys/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577677427820517794" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />A large left middle cranial fossa subdural empyema is demonstrated, with a relatively thin rim of enhancement. Internally, there is a large quantity of debris. There is mass effect, with a modest midline shift and effacement of the left lateral ventricle. Inflammatory changes are demonstrated in the left temporal bone which is likely the source of the abscess. There is diffusion restriction, not marked, consistent with abscess. There is extensive dural enhancement, along with considerable surrounding edema.<br /><br />Differential diagnosis:<br />- Subdural empyema<br />- Chronic subdural hematoma<br />- Subdural effusion<br />- Subdural hygroma<br />- Dural metastasis<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Large left middle cranial fossa subdural empyema; left mastoiditis</span><br /><br /><br /><span style="font-style:italic;">Key points</span><br /><br />Loculated collection of pus in subdural space<br />Best diagnostic clue: Extra-axial collection with contrast enhancing rim<br />Supratentorial typical<br />Infratentorial (up to 10%), often associated with mastoiditis<br />Crescentic typical; may be lens shaped on coronal images<br />CT demonstrates extra-axial collection, iso-to hyper dense to CSF on noncontrasted CT; shows strong peripheral enhancement with contrast<br />Best imaging tool: MR with DWI to demonstrate presence, nature, extent and complications<br />T1W image shows:<br />Extra-axial collection hyper intense to CSF<br />Crescentic extra-axial collection<br />T2WI demonstrates a lesion that is Iso-to hyper intense to CSF,<br />FLAIR shows a crescentic fluid collection which is hyper intense to CSF, underlying brain may be hyper intense<br />DWI shows restricted diffusion (increased signal intensity); Differentiates subdural empyema from subdural effusions<br />T1WI post contrast shows:<br />Prominent enhancement at margin related to granulomatous tissue and inflammation<br />Encapsulating membranes enhance strongly, may be loculated with internal fibrous strands<br />May see enhancement of adjacent brain parenchyma<br />MRV may show venous thrombosis seen as a lack of flow<br />CT may miss small collections<br />Complications include cerebritis and brain abscess, cortical vein and dural sinus thrombosis, and cerebral edema<br />Subdural empyema is much more common than epidural empyema<br />In older children, adults: Related to paranasal sinus disease (>2/3), in infants and young children it can be a complication of bacterial meningitis<br />Most common signs/symptoms include fever, headaches, meningismus, sinusitis, cerebritis<br />Sinus or ear infection in > 75% of cases<br />Confused with meningitis which may lead to delayed diagnosis<br />Can occur at any age<br />Rare, yet high mortality rate.<br />If subdural or epidural abscess is discovered, look also for sinusitis, otomastoiditis, dural sinus thrombosis and brain abscess<br />Progresses rapidly, neurosurgical emergency<br />Surgical drainage via wide craniotomy is gold standardUnknownnoreply@blogger.com2tag:blogger.com,1999:blog-2369979688209795962.post-78389735189095554452010-12-31T16:00:00.000+01:002011-02-26T14:33:30.771+01:00Benign perimesencephalic SAH<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidT5qBPlv6Mb_ae2a0HXS_-AORsHU91_At8WCBLfbl0uWGzccOjlv1l0n_LeNzPD55jDIY4zJbvL8Z74q05-AbxBA9_yXZ_xpEgvfbMajDwOVZPYahmDJfTSduDku8wjlGSP5ROQnr-5Y/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidT5qBPlv6Mb_ae2a0HXS_-AORsHU91_At8WCBLfbl0uWGzccOjlv1l0n_LeNzPD55jDIY4zJbvL8Z74q05-AbxBA9_yXZ_xpEgvfbMajDwOVZPYahmDJfTSduDku8wjlGSP5ROQnr-5Y/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577990157116512834" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjhumy3NaRcJaog5vmGyu-VQO-8ajKiRGNxYQgT4-SGHbRDyfU035rKBuU47wGQwH-jUze3fk44_Zn4Lj7v-q0De4bKGcW0Veo3G8MZI10777Gkfe4lCqPnVc3oOSzoxLqWwZvNX51cviI/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjhumy3NaRcJaog5vmGyu-VQO-8ajKiRGNxYQgT4-SGHbRDyfU035rKBuU47wGQwH-jUze3fk44_Zn4Lj7v-q0De4bKGcW0Veo3G8MZI10777Gkfe4lCqPnVc3oOSzoxLqWwZvNX51cviI/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577990097896332594" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhVFyY2FmvCaBv79QNMSmDyhdt32-Vz48V95xwb5v5eBsMmELxmEUwsX-z-7oMqmEO3QBuQY1W-F75n4XJIL_hWnPunUQ_TWFFl-oX0SXVEW5IDeO4KvP1_nqvoKwj1h7LBFllV4lEUqSQ/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhVFyY2FmvCaBv79QNMSmDyhdt32-Vz48V95xwb5v5eBsMmELxmEUwsX-z-7oMqmEO3QBuQY1W-F75n4XJIL_hWnPunUQ_TWFFl-oX0SXVEW5IDeO4KvP1_nqvoKwj1h7LBFllV4lEUqSQ/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577989674729186162" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1, Figure 2, and Figure 3: Axial CT images of the brain demonstrate SAH in the premedullary, prepontine, suprasellar, and interpeduncular cisterns.<br />Other figures (not shown): Representative images from a 4-vessel cerebral angiogram demonstrate no evidence of aneurysm or vascular malformation.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Benign perimesencephalic SAH</span><br /><br /><br />Trauma and aneurysm are the two most common causes of SAH. At least 80% of cases of atraumatic SAH are caused by rupture of an intracranial aneurysm. When SAH is present, many clinicians request CT or MR angiography in order to quickly and non-invasively diagnose aneurysm. If an aneurysm is not detected with one of these modalities, conventional cerebral angiography (the gold standard for exclusion of aneurysm) is necessary. If the initial angiogram is negative, a second cerebral angiogram, typically performed 1-3 weeks after the first, is mandatory. This is because occasionally an aneurysm will be missed on the initial angiogram due to spasm or partial/complete thrombosis. The diagnosis of non-aneurysmal SAH can be applied to patients who have two consecutive negative technically adequate 4-vessel cerebral angiograms. Additionally, many clinicians request MRI of the spine to exclude the possibility of spinal AVM as a source for SAH.<br /><br />The classic variety of non-aneurysmal SAH is known as benign perimesencephalic SAH or pretruncal nonaneurysmal SAH. As the name implies, the hemorrhage is situated around the midbrain and anterior to the brainstem in the ambient, interpeduncular, and prepontine cisterns. The term “benign” refers to the fact that after recovery from the initial episode, there is no increased risk of repeat hemorrhage. Cerebral vasospasm is less likely in these patients, but does occur. Hydrocephalus also remains a possibility during the acute phase. Although not clearly understood, one proposed mechanism of benign perimesencephalic SAH is rupture of the venous plexus anterior to the pons (the anterior pontomesencephalic plexus). This is postulated to occur as a result of increased venous pressure from strenuous activities such as exercise. Intramural hematoma of the basilar artery and rupture of a basilar perforating artery have also been suggested as alternate hypotheses.<br /><br />Although benign perimesencephalic SAH has been known as a distinct clinical entity for some time, patients may present with non-aneurysmal SAH in an atypical distribution (non-perimesencephalic). In some of these patients, the total volume of hemorrhage is increased such that blood is present throughout the basal cisterns and extends over the cerebral convexities. In other patients, the hemorrhage is confined to the convexities, quadrigeminal cistern, or other atypical locations. In today’s case, Patient #1 presented with the classic variety of benign perimesencephalic SAH. Patient #2 presented with atypical non-aneurysmal SAH. Both patients recovered, and have had no repeat episodes of hemorrhage to date.<br /><br />Possible causes of SAH:<br />- Trauma<br />- Aneurysm<br />- AVM<br />- Vasculitis<br />- Dural AV fistula<br />- Extension from intraparenchymal hemorrhage<br />- Dural venous sinus thrombosis<br />- Infection<br />- Neoplasm<br />- IdiopathicUnknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-30224833458847386572010-12-27T16:00:00.001+01:002011-02-25T18:08:07.601+01:00Lumbar disc extrusion with a wrapped disc<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5wHw22yVzBYrVBAbVt9cXQkiykQAY1f9nnXIrAaZpJyuPEVbUwxnTljEi1xUN6SJvE0gnUNRYyGHwrHLmBbB-ZKtqEvz-5Sa2QKg-ryeLBrbnxQ1160kxixlAFA_S9ILTSh134BvQabk/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 353px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5wHw22yVzBYrVBAbVt9cXQkiykQAY1f9nnXIrAaZpJyuPEVbUwxnTljEi1xUN6SJvE0gnUNRYyGHwrHLmBbB-ZKtqEvz-5Sa2QKg-ryeLBrbnxQ1160kxixlAFA_S9ILTSh134BvQabk/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577673678532185490" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhx8joz3rUXMXpJvi2q8CRsZwrZytcdbfbHGki7sV12yuPESnLR8l6zr7r6XqtYnb0UAMSe_Eia1by7HgDo7HaVpx7G90UeavmJgNfDpNgmEP224aXDoY_cEhVUfAWINUYADJMYLm3cKII/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 368px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhx8joz3rUXMXpJvi2q8CRsZwrZytcdbfbHGki7sV12yuPESnLR8l6zr7r6XqtYnb0UAMSe_Eia1by7HgDo7HaVpx7G90UeavmJgNfDpNgmEP224aXDoY_cEhVUfAWINUYADJMYLm3cKII/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577673593311300546" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6U6p3ErR2W90C07PtWQhc9ygCtK9q6MReaAi6AX4CJvVjoEIdWrI9al8f1GnzzhkG59toLwDdbwKFCsyul0ydIijAuvhaL0XOkTrQ6j8Sou3m6cSKcUjx1Oc6ELv1jLICnx5kygpTsFI/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 395px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6U6p3ErR2W90C07PtWQhc9ygCtK9q6MReaAi6AX4CJvVjoEIdWrI9al8f1GnzzhkG59toLwDdbwKFCsyul0ydIijAuvhaL0XOkTrQ6j8Sou3m6cSKcUjx1Oc6ELv1jLICnx5kygpTsFI/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577673454864580130" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPUFD8fOp0yeV5dMKHY0l-ESimXwTgtQqF8-E4XKUixf2iPfXVAUqnZuddHP62lipXUdy_eM9DT3-ldepEhWprOBmj1Crlg1YSvDh5PxnYuhP1Dv342CGTsGZfFs86XKZUxxGLjw8f-Y0/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 388px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPUFD8fOp0yeV5dMKHY0l-ESimXwTgtQqF8-E4XKUixf2iPfXVAUqnZuddHP62lipXUdy_eM9DT3-ldepEhWprOBmj1Crlg1YSvDh5PxnYuhP1Dv342CGTsGZfFs86XKZUxxGLjw8f-Y0/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577673363544486306" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />There is a left central disc extrusion at L5-S1 that causes mild to moderate left lateral recess narrowing and nerve root displacement without nerve root compression. At this level there is also contrast enhancement traversing the left laminectomy defect and encasing the disc extrusion, consistent with a wrapped disc. There is enhancement in the left lateral recess, suggesting post-operative fibrosis.<br /> <br />Differential diagnosis:<br />- Wrapped disc<br />- Peridural fibrosis<br />- Epidural abscess<br />- Epidural metastasis<br />- Nerve sheath tumor<br />- Disc pseudobulge<br />- Intervertebral disc protrusion<br />- Intervertebral disc extrusion<br />- Recurrent intervertebral disc herniation<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Lumbar disc extrusion with a wrapped disc</span><br /><br /><br /><span style="font-style:italic;">Key points: "Wrapped" disc </span><br /><br /><br />Disc herniation (protrusion, extrusion, or fragment) may be caused by trauma, repetitive or acute, and are a common source of pain and subsequent back surgery in the general population. In the acute phase, the herniated disc stimulates a fibrovascular response. A "wrapped disc" is the focal herniation (protrusion, extrusion, or fragment) that is encased in vascular scar tissue stimulated by this response and is evident by enhancement on contrast-enhanced T1-weighted images.<br /><br />Asymptomatic or low back pain and/or radiculopathy are most common in the lumbar spine at L4-L5 and L5-S1. A wrapped disc is a post-surgical sequela, particularly following surgery for spinal stenosis in which the surgical procedure is more extensive, involving a laminectomy and a medial facetectomy.<br /><br />Best imaging modality: MR (sequences: sagittal and axial T2WI and T1WI, as well as contrast-enhanced axial and sagittal T1WI)<br />Other imaging modalities: CT, myelography<br /><br /><br /><span style="font-style:italic;">Imaging findings</span><br /><br />MR: Anterior extradural mass contiguous with the disc space extending into the spinal canal<br />*Contrast-enhanced T1WI: Peripheral enhancement surrounding the disc herniation or fragment with/without central canal, lateral recess, or foraminal stenosis and cord or nerve root impingement. (*most helpful MR sequence)<br />Non-enhanced T1WI: Isointense to parent disc<br />T2WI: Iso- to hyper intense to parent disc<br />General disc hypointensity and height loss at the level of the herniation, as well as postoperative changes (laminectomy defects, etc), degenerative facet disease, and osteophytes, are common associated findings.<br />CT:<br />Non-contrast CT: An anterior extradural soft tissue mass that may displace the nerve root / indent the thecal sac<br />Contrast-enhanced CT: Mild peripheral enhancement of the disc herniation/fragment<br />Myelography: An extradural mass that indents the thecal sac and nerve root sleeves<br />Imaging findings of other common differential diagnoses<br />Peridural fibrosis: Scar within epidural space after lumbar surgery that infiltrates epidural fat, causing homogeneous enhancement that diffusely surrounds the thecal sac and nerve root; increased in T2 signal relative to adjacent disc herniation<br />Epidural abscess: A distinct fluid collection in the epidural space with peripheral enhancement on post-contrast images, often associated with findings of diskitis<br />Epidural metastasis: Elongated (cranial-caudal orientation) enhancing mass with osseous involvement and may demonstrate paravertebral extension<br />Nerve sheath tumor: Avid enhancement surrounding the nerve root, some of which are in a "dumbbell" shape<br />Disc pseudobulge: Smooth generalized extension of the disc margin without a focal defect due to "uncovering" of disc related to spondylolisthesis<br />Intervertebral disc protrusion: Anterior extradural mass contiguous with disc space and triangular in shape with broader base than apex; no enhancement<br />Intervertebral disc extrusion: Anterior extradural mass contiguous with disc space by a "neck," in which this herniated disc material then widens in the epidural space<br />Recurrent intervertebral disc herniation: Extradural mass contiguous with intervertebral disc margin, demonstrating enhancement peripherally but without central enhancement<br />Treatment<br />Conservative: Anti-inflammatory and pain medications, avoid trauma<br />Surgical: Repeat surgery to remove herniated disc (protrusion, extrusion, fragment)Unknownnoreply@blogger.com7tag:blogger.com,1999:blog-2369979688209795962.post-70004645146580737582010-12-24T16:00:00.001+01:002011-02-26T14:20:14.551+01:00Pseudotumor cerebri - Idiopathic Intracranial Hypertension (IIH)<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgezJk5xqE348NpeTszWKzRyCh9o6ZWQ2_tm9xDEiH_hoTKVrXzeCKn6XPo_1HP8d0iDyfn_B7hsF1iwNKwH0z2GoCt4nx4s91cDziE_5HOGC5YzNmy3SsQEP5rGyg3VWxXpIqCZfK1n64/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 320px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgezJk5xqE348NpeTszWKzRyCh9o6ZWQ2_tm9xDEiH_hoTKVrXzeCKn6XPo_1HP8d0iDyfn_B7hsF1iwNKwH0z2GoCt4nx4s91cDziE_5HOGC5YzNmy3SsQEP5rGyg3VWxXpIqCZfK1n64/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983612527216370" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkwFgqNgBjYMT5UwA5I3OLANRMh-8UuWAyfng_fF8W4XMUP61ED7KrXRZn-P5IUkAfKNWgnMQO57RKVufoFWktyxm1LlPgPYI2c6isr9TvN4BwkmoFjvW_qFh5Q6_7bNVzdciiMo5yOgE/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkwFgqNgBjYMT5UwA5I3OLANRMh-8UuWAyfng_fF8W4XMUP61ED7KrXRZn-P5IUkAfKNWgnMQO57RKVufoFWktyxm1LlPgPYI2c6isr9TvN4BwkmoFjvW_qFh5Q6_7bNVzdciiMo5yOgE/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983569218587362" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQRSg2_ln-tLpBJ4MnDBmpK-QRcmEfTRvKqVzjJaZCwlQseTf7f1SzKMbFVUaalQMby2kEaGwmhvn31rNDQGSfiVr2PZxWxHqjeWTgi4Xy30uGDcmm8GMVMXzXAxUwH7uGQf5RyovaOeU/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQRSg2_ln-tLpBJ4MnDBmpK-QRcmEfTRvKqVzjJaZCwlQseTf7f1SzKMbFVUaalQMby2kEaGwmhvn31rNDQGSfiVr2PZxWxHqjeWTgi4Xy30uGDcmm8GMVMXzXAxUwH7uGQf5RyovaOeU/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983517397886786" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjOgl76s0hJCqz_xMsyBYNJPG7ZO3FBF9ugAzR1V33vbOAKtwY3vreG3d6sVh4WZ_9jwKYmu16ew-MgynzAFbPGur12UkZ9uovAXzGc0eRajM3Bx-qE8UmS62Fk4H3GfYOF-R2IshdpWao/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjOgl76s0hJCqz_xMsyBYNJPG7ZO3FBF9ugAzR1V33vbOAKtwY3vreG3d6sVh4WZ_9jwKYmu16ew-MgynzAFbPGur12UkZ9uovAXzGc0eRajM3Bx-qE8UmS62Fk4H3GfYOF-R2IshdpWao/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983457590219586" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1ic_ZK12xP9Nr-Uj5ZvX7rMrx9I03IoLgMgoqd3GFwMii2zAHnne5RWUqU_pnZScVm381URXS-jbqFT2U09q4tq9SFFTVaH72v2HwlG_SQM2ExrML1QpytPfgNvzJZd09TCxfQuJhDhk/s1600/5.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1ic_ZK12xP9Nr-Uj5ZvX7rMrx9I03IoLgMgoqd3GFwMii2zAHnne5RWUqU_pnZScVm381URXS-jbqFT2U09q4tq9SFFTVaH72v2HwlG_SQM2ExrML1QpytPfgNvzJZd09TCxfQuJhDhk/s400/5.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983383550356530" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEih8_psDsSEYQPmrjcqe7SdVrJ9NI1G5eX2trmKn0sdR-uKFEFnYAgUX-h4RjY5LFEqxcU1Joa-DUl08T7LOeJaUD8YmULj0I3kCABuFBul9LZQfWbl3elU6S0j5sxD9NHtbOImlqC_ao0/s1600/6.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEih8_psDsSEYQPmrjcqe7SdVrJ9NI1G5eX2trmKn0sdR-uKFEFnYAgUX-h4RjY5LFEqxcU1Joa-DUl08T7LOeJaUD8YmULj0I3kCABuFBul9LZQfWbl3elU6S0j5sxD9NHtbOImlqC_ao0/s400/6.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983305407618402" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi5hFLSB9vrGrp9mCdqhyphenhyphenKprC6TeQ1IGyr9VYCDIFJy33ITGMDQQNSAJFDRaKsOBRTsMZ4xvHENqc-on3cQLAI94SWhOs2CbmBXBYeZ6JgaHT68_xAKP95IMweGi0U9AaqjPu8C8fbiR1w/s1600/7.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi5hFLSB9vrGrp9mCdqhyphenhyphenKprC6TeQ1IGyr9VYCDIFJy33ITGMDQQNSAJFDRaKsOBRTsMZ4xvHENqc-on3cQLAI94SWhOs2CbmBXBYeZ6JgaHT68_xAKP95IMweGi0U9AaqjPu8C8fbiR1w/s400/7.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5577983225173028594" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />T2W axial MRI (Figure 1) shows signs of increased ICP, but only increased fluid within the optic nerve sheaths, flattening of the posterior orbit, and a partially empty sella. <br />The 3D TOF MRV Towne and RPO projections (Figure 2 and Figure 3) show bilateral, right greater than left, focal transverse-sigmoid venous sinus junction narrowing’s. It is not a normal MRV given the pt’s history, with more explanation in the discussion. There is no aneurysm or collection of collateral blood vessels seen in these images.<br /><br />The AP and lateral (Figure 4 and Figure 5) venous phase carotid arteriogram shows long segment stenosis at transverse-sigmoid venous sinus junction distal to the vein of Labbé. Pre procedure venography showed a venous pressure gradient across this lesion of 17 mmH2O with 37 mmH2O on transverse sinus side and 15 mmH2O on internal jugular vein side.<br /><br />AP and lateral (Figure 6 and Figure 7) venous phase carotid arteriogram shows long segment stenosis at transverse-sigmoid venous sinus junction with a balloon crossing the gradient lesion. <br /><br /><br /><span style="font-weight:bold;">Diagnosis: Pseudotumor cerebri - Idiopathic Intracranial Hypertension (IIH)</span><br /><br /><br />Pseudotumor cerebri is defined by typical clinical symptoms which occur in the setting of elevated “idiopathic” ICP and a normal composition of CSF. Classic clinical symptoms include diffuse recalcitrant headaches, vision changes (including vision loss), and hearing changes (e.g., tinnitus), and the disease is typically seen in obese women who are 20-50 years of age. Papilledema is the most common physical exam finding, but visual loss and sixth nerve palsy are also seen. Other symptoms include disabling headaches and blindness. LP opening pressure is greater than 25 cm H2O. Brain computed tomography (CT) and magnetic resonance imaging (MRI) are typically normal, however, the following suggestive non-pathognomonic findings are frequently present:<br /><br />– Cerebral venous sinus stenoses<br />– Flattening of the bilateral posterior sclera<br />– Partially or fully empty sella; enlargement of the chiasmatic recess of the 3rd ventricle<br />– Distension of perioptic nerve subarachnoid space<br />– Intraocular protrusion of the optic nerve head<br />– Orbital optic nerve vertical tortuosity<br /><br />Treatment for pseudotumor cerebri typically includes medical management with acetazolamide and pain control for headaches. Furosemide and corticosteroids have been used, as well. Surgical interventions to treat pseudotumor cerebri include lumboperitoneal shunt (LPS) and ventriculoperitoneal shunt (VPS), which often produce immediate results, however, eventual return of pseudotumor symptoms occur in approximately 50% within three years. Optic nerve sheath fenestration is also used to treat vision changes, with variable headache relief. Dominant transverse/sigmoid venous sinus angioplasty and stenting are relatively new methods for the treatment of pseudotumor cerebri for those who have significant dural sinus stenosis. Given that 80% of intracranial vascular compliance is provided from the venous vasculature, reduction of pressure in the sinuses reduces CSF pressure. Better results are achieved in patients with documented high pressure gradients, and greater efficacy is seen with regard to arrest of visual loss (>90%) than with headache relief (~50%). Long-term results are lacking. however. <br /><br />In this case, cerebral angiography demonstrated bilateral high-grade transverse/sigmoid sinus stenoses distal to vein of Labbe insertions. Selective catheterization of the right transverse sinus revealed an estimated 80% narrowing to a luminal diameter of 1mm, and a pressure gradient across the stenosis of 13 mmHg (normal <5 mmHg). The contralateral sinus was smaller, but distally stenotic. A stent was placed across the right sided stenosis.<br />The patient was placed on antiplatelet medication to preserve stent patency immediately after the procedure. She had no headaches after the procedure and demonstrated objective visual improvement at her one- and six-week follow-up examinations.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-41464148024709396852010-12-22T16:00:00.001+01:002011-02-25T18:38:23.580+01:00Intracranial pseudotumor (Tolosa-Hunt syndrome)<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVPq8EZmutyjR3Eqt8vDI3eHtilCQ9LHNJQAf67hw23awlXEBhajrrID4kpSJR5WYbqFqj7jqkoFQ2mFb2Xvq2EReNFvIlgxlk42z5KPdQY0tEWpgEVwQ6rvpnVo7t_6vUECXO580M7QM/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 330px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVPq8EZmutyjR3Eqt8vDI3eHtilCQ9LHNJQAf67hw23awlXEBhajrrID4kpSJR5WYbqFqj7jqkoFQ2mFb2Xvq2EReNFvIlgxlk42z5KPdQY0tEWpgEVwQ6rvpnVo7t_6vUECXO580M7QM/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577669160308589090" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgq3xc2M-0BuAkUCUv5HD5WJ25JtxvrhC6G4LziyvNa-1DGAgpAJAjVi1SLpVRihQAfaj9HqY1Tq78n3hsANRRx4wGuPH-lOr2PaKbbq7vnUrz6wMxQ0Hx8MVsHrjfbqTRbjQ5Cj0D_Ni8/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 356px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgq3xc2M-0BuAkUCUv5HD5WJ25JtxvrhC6G4LziyvNa-1DGAgpAJAjVi1SLpVRihQAfaj9HqY1Tq78n3hsANRRx4wGuPH-lOr2PaKbbq7vnUrz6wMxQ0Hx8MVsHrjfbqTRbjQ5Cj0D_Ni8/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577669090177632530" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgW0t_u5GU1phm2CZXRyNPF7U_aQzPjWtb_YTh1h5anLP2SMbIKBvzR4YzKof8Tgl6pCjZ8dv1k_S-lrG_5KG2YFFFOHmdxbHw3IZXEGI74n3DYqvBeNJlbZBvAtKIU6YX7zxOvJcpYol0/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 387px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgW0t_u5GU1phm2CZXRyNPF7U_aQzPjWtb_YTh1h5anLP2SMbIKBvzR4YzKof8Tgl6pCjZ8dv1k_S-lrG_5KG2YFFFOHmdxbHw3IZXEGI74n3DYqvBeNJlbZBvAtKIU6YX7zxOvJcpYol0/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577669023225575010" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh41bFNf8J1G97dlWYV8YEbelbB3CwGtYfkSoW3B3FvGALfwxxE3WJ99Q2X8VcTg8HVaM2wW1M2OKPeaoH6JjwB084vUY5eOjOeTn9c5FV5Catg3w1f_8SMNrkXML9ehSKDsxYO5g_Bepg/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh41bFNf8J1G97dlWYV8YEbelbB3CwGtYfkSoW3B3FvGALfwxxE3WJ99Q2X8VcTg8HVaM2wW1M2OKPeaoH6JjwB084vUY5eOjOeTn9c5FV5Catg3w1f_8SMNrkXML9ehSKDsxYO5g_Bepg/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577668951556368994" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_Ph0JZ0yI2GVmu23hyhUalcNf1gbo9fD79nOCP_jHDwaAwQCcRWABRpuBIy6x2ZOQIWg8xYuwfhu9TNeiPU5CeZHgKBpp4SJEg2v8la8q7c4S1mzuNrXgchsKyk2OmkbUHMY4IDfjsZI/s1600/5.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 326px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_Ph0JZ0yI2GVmu23hyhUalcNf1gbo9fD79nOCP_jHDwaAwQCcRWABRpuBIy6x2ZOQIWg8xYuwfhu9TNeiPU5CeZHgKBpp4SJEg2v8la8q7c4S1mzuNrXgchsKyk2OmkbUHMY4IDfjsZI/s400/5.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577668724225538050" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Increased CSF signal demonstrated by T2 hyper intensity within the right optic sheath. Nodular enhancement at the superior aspect of the right optic nerve at the orbital apex, which extends with prominent nodular enhancement posteriorly along the dural reflection of the right cavernous sinus. Asymmetric dilatation of the right superior ophthalmic vein.<br /><br />Differential diagnosis:<br />- Meningitis<br />- Sarcoidosis<br />- En plaque meningioma<br />- Meningeal metastases<br />- Meningeal Non-Hodgkin's lymphoma<br />- Tolosa-Hunt syndrome<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Intracranial pseudotumor (Tolosa-Hunt syndrome)</span><br /><br /><br /><span style="font-style:italic;">Discussion</span><br /><br />Intracranial pseudotumor (Tolosa-Hunt syndrome) is a part of a spectrum of "quasineoplastic" lesions that demonstrate orbital, intracranial, or pulmonary involvement, and include such other disorders as plasma cell granuloma and hypertrophic cranial pachymeningitis. It is a chronic granulomatous disease of unknown origin, which has been hypothesized to represent a low grade fibrosarcoma of inflammatory cells versus an autoimmune phenomenon. While Tolosa-Hunt syndrome is rare, orbital pseudotumor is the third most common ophthalmic disorder, and encompasses 5-8% of all orbital masses. Histologically, the lesions of Tolosa-Hunt demonstrate mixed lymphocytic and plasma cell infiltrate, with a variable degree of fibrosis. Lesions favor the cavernous sinus and basal meninges, although falcine and tentorial lesions have been described.<br /><br />Patients with intracranial lesions are more frequently young adults, who present initially with chronic headaches or cranial nerve palsies. Patients with orbital involvement are more frequently middle-aged, and may present with painful proptosis and vision loss . Symptoms may be intractable, leading to severe disability. Untreated or unresponsive disease may progress to death. First-line treatment is invariably high-dose steroids, with radiotherapy or surgical resection reserved for patients with incomplete response to steroids .<br /><br /><br /><span style="font-style:italic;">Radiologic Overview of the diagnosis</span><br /><br />The imaging hallmarks of Tolosa-Hunt syndrome are characterized by an enhancing, infiltrating meningeal mass, which favors the cavernous sinus or basal meninges, although falcine and tentorial involvement has been described . Focal meningeal thickening may range from just a few millimeters to a greater than 2 cm rind. With intracranial pseudotumor, orbital involvement is spared more than 90% of the time. Tolosa-Hunt remains a diagnosis of exclusion, once meningitis, en plaque meningioma, and meningeal metastases are ruled out.<br /><br />The imaging modality of choice for imaging patients with Tolosa-Hunt remains MRI, although useful information may be gleaned from other modalities. On non-contrast enhanced CT (NECT), there are no specific findings to suggest the diagnosis; however, this modality may be of some value in differentiating the lesion from en plaque meningioma. On contrast enhanced CT (CECT), salient imaging findings include enhancing, thickened meninges or a curvilinear appearance of a single meningeal region. As aforementioned, MRI remains the primary modality for diagnosis of Tolosa-Hunt syndrome, and each sequence may provide critical information required to make the diagnosis. On T1WI, one may find focal thickening of the meninges that is isointense to gray matter. On T2WI, lesions are characterized as iso- to hypo intense regions of focal meningeal thickening, which may be more hypo intense as they become more fibrotic. FLAIR is of little help in making the diagnosis, but it is unlikely to demonstrate focal brain edema underlying the lesion . Contrast enhanced T1WI is the single most valuable sequence for evaluation of Tolosa-Hunt syndrome, and is characterized by diffusely enhancing region of meningeal thickening, which may range from a few millimeters to greater than 2 cm in some cases. Diffuse boney infiltrates may be appreciated on fat saturated contrast enhanced T1 sequence. While angiography is not considered a primary modality, severe disease may result in carotid artery narrowing, thus MRA may be a useful adjunct in the appropriate clinical setting.<br /><br />The appropriate differential diagnosis of Tolosa-Hunt syndrome includes meningitis, sarcoidosis, en plaque meningioma, meningeal metastases, and meningeal Non-Hodgkin's lymphoma.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-61779554261390931432010-12-17T16:00:00.002+01:002011-02-25T17:37:23.832+01:00Hypertensive intracranial hemorrhage<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiqd_MkbLATcZKawM6owyqk5rMCjdaKcbhkAfuEzbCU76OI0AP7VkuxDI0_6r9buU_YXLY6DDnhLXqa-VGEZqxaz4EoS8JamwhS0_K0VHTOVVr9Nco0OPiLsHkV3D19kCGIFv8LcJma2Q/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 318px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiqd_MkbLATcZKawM6owyqk5rMCjdaKcbhkAfuEzbCU76OI0AP7VkuxDI0_6r9buU_YXLY6DDnhLXqa-VGEZqxaz4EoS8JamwhS0_K0VHTOVVr9Nco0OPiLsHkV3D19kCGIFv8LcJma2Q/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577664858020824242" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEif0DtQDWN3quDoY9x5EyroOrUJ4lmNbJ6FlvZDFhzfmb5JCD1F2duAAcdPzkqyTrdaRHJWHzYIamSa3UAPLGvIMhpI34tPC63uHUdQWqtJPR3clD6o1REfZRFfe1LIekWnnJEmvJQAv34/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 351px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEif0DtQDWN3quDoY9x5EyroOrUJ4lmNbJ6FlvZDFhzfmb5JCD1F2duAAcdPzkqyTrdaRHJWHzYIamSa3UAPLGvIMhpI34tPC63uHUdQWqtJPR3clD6o1REfZRFfe1LIekWnnJEmvJQAv34/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577666387860494738" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdSDLmGmEHZilZ22lJ4qpJvngVfCILQg0sYFcLV-1V8wQbDqr_D46Erb5S4NOH6S76gII8qvrskNYPxvNAAn7lJo_RETYZzXwuMTtn4LK26MtmgZn1QOatkZjjoykMD9pT5BP6tIZ3qKA/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 349px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdSDLmGmEHZilZ22lJ4qpJvngVfCILQg0sYFcLV-1V8wQbDqr_D46Erb5S4NOH6S76gII8qvrskNYPxvNAAn7lJo_RETYZzXwuMTtn4LK26MtmgZn1QOatkZjjoykMD9pT5BP6tIZ3qKA/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577663970245601698" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Axial CT of the head shows a large hyper dense focus with peripheral hypo density in the left frontal lobe, causing sulcal effacement at the frontal cortex but no significant midline shift. Surrounding rim of low density represents edema (image 1). Unenhanced MRI of the brain shows an the same mass-like focus in the left frontal lobe, which has an isointense center with a hyper intense rim (image 2). Post gadolinium-enhanced T1 image of the brain shows no internal enhancement of this lesion (image 3).<br /><br /><br />Differential diagnosis:<br />- Hypertensive intracranial hemorrhage<br />- Ruptured arteriovenous malformation (AVM)<br />- Hemorrhagic intracranial mass<br />- Posttraumatic cerebral contusion<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Hypertensive intracranial hemorrhage</span><br /><br /> <br />Acute blood appears hyper dense of unenhanced head CT.<br />Without a history of trauma, intraparenchymal brain hemorrhage on head CT could represent a hemorrhagic mass, a ruptured AVM, or a hemorrhagic brain tumor (primary or metastatic).<br />MRI with and without contrast is the best diagnostic tool for determining if a mass lesion is present, and for evaluating the age of the intracranial hemorrhage.<br />Acute blood products on T1 appear hypo intense to isointense (image 2), whereas subacute and chronic hematoma are hyper intense.<br />Neoplasms should enhance on post contrast T1. The lack of enhancement in this patient on post contrast T1 excludes neoplasm (image 3).Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-16492821039607791092010-12-16T16:00:00.000+01:002011-02-25T17:21:57.924+01:00Sequestered disk<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgTekcGRv-YGhVZayMeSle3gTVcgRX1J1Qe8eypkxT-90X0qIjRgPSTslXv8Kmys1OrdBnJvpDeHkYLZ484tlLkF4cKc9kJECWUSlgKhn32wqyRjcGBB_Y8-YxaC7EW5m8rFuDmiIb3FFg/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 249px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgTekcGRv-YGhVZayMeSle3gTVcgRX1J1Qe8eypkxT-90X0qIjRgPSTslXv8Kmys1OrdBnJvpDeHkYLZ484tlLkF4cKc9kJECWUSlgKhn32wqyRjcGBB_Y8-YxaC7EW5m8rFuDmiIb3FFg/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577660940184278722" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhseN_8LyBIqnhG10poSOMGdcPH8IkUTIfAmdHgslWziR1j4Eg_C6RNI65TxiZwHohuUEsOk11PMGJ7oTB1hLkKozwCfLZVFj5MZ1DPHckrysGndh8nS-HUfrG4WhFIwqnLqA6fbnVB__U/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 210px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhseN_8LyBIqnhG10poSOMGdcPH8IkUTIfAmdHgslWziR1j4Eg_C6RNI65TxiZwHohuUEsOk11PMGJ7oTB1hLkKozwCfLZVFj5MZ1DPHckrysGndh8nS-HUfrG4WhFIwqnLqA6fbnVB__U/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577660871643417714" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEMe6ogfMT2sYiUrBt7MbvKw-JhKzyALzddd0e7xIGIy_TuPkvUbGhRMV-amAa0t0ouoOD70z-9nKStiAcxrX_kBEUNWqdd-dpLLmDcN8yf0Ei_6m_WAbgjVUqwLqumSQuJFY42qlNzvM/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 249px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEMe6ogfMT2sYiUrBt7MbvKw-JhKzyALzddd0e7xIGIy_TuPkvUbGhRMV-amAa0t0ouoOD70z-9nKStiAcxrX_kBEUNWqdd-dpLLmDcN8yf0Ei_6m_WAbgjVUqwLqumSQuJFY42qlNzvM/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577660804181923618" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqPX_wPhPHKptBRMU6lVv1OCyU19feqe4SRTBdqfUxlbtzC31_eIUJuGbUtbZ3TAd-Nn4553PQRGBMACcfP2In3aryPgqEjzJybZE5cFUs5XohiM0aN5LuAbif99d1jrmP9IujZB46rLE/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 256px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqPX_wPhPHKptBRMU6lVv1OCyU19feqe4SRTBdqfUxlbtzC31_eIUJuGbUtbZ3TAd-Nn4553PQRGBMACcfP2In3aryPgqEjzJybZE5cFUs5XohiM0aN5LuAbif99d1jrmP9IujZB46rLE/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577660553405472434" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />There is an non- enhancing ovoid mass slightly hyper intense to muscle on both T1 and T2 sequences, in the anterior epidural space at the L3 level, measuring approximatelyl 12 x 8 x 12 mm. This is not contiguous with any adjacent disks. No signal dropout on fat-saturated sequences. The mass causes severe stenosis of the left half of the spinal canal at the L3 level, compressing the left descending nerve roots. T1 and T2 hyper intensity at the endplates abutting L2-L3 disc space representing Modic Type II changes. There is intervertebral disk space height loss at L2-L3 with severe disk desiccation changes.<br /><br /><br />Differential diagnosis:<br />- Sequestered disk<br />- Extruded disk<br />- Failed back surgery<br />- Epidermoid<br />- Epidural abscess<br />- Epidural hematoma<br />- Lipoma<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Sequestered disk</span><br /><br /><br />A focal disk protrusion is an extension of intervertebral disc material (nucleus pulposus) beyond the vertebral margin (AP diameter < mediolateral diameter). An extruded disk is one in which the nucleus pulposus has herniated through a rent in the annulus fibrosis. The AP diameter > ML diameter, and the disk may migrate craniocaudally, but maintains attachment to the parent disk (frequently symptomatic).<br />When extruded disk material loses its attachment to the parent disk, it is referred to as a sequestered disk. Sequestered discs usually lodge in the anterior epidural space (AES), just anterior to the posterior longitudinal ligament, and migrate either cephalad or caudad (with equal frequency). Because there is a midline septum associated with the PLL in the AES, the fragment is usually just off midline (to the right or left). Rarely, the sequestered fragment may migrate beyond the PLL into the posterior epidural space, through the dural ( intrathecal location), or into the paraspinal muscles.<br />They usually resemble the parent disk on MR, with T1 hypo intense and T2 iso- / hypo intense. There may be surrounding T2 hyper intensity and a rim of enhancement from inflammatory changes.<br />This is a crucial diagnosis to make, as a sequestered disk is a contraindication to limited disk procedures (e.g. Percutaneous discectomy) and may result in failed back surgery.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-36675013826732085972010-12-14T16:00:00.002+01:002011-02-26T13:19:29.980+01:00Myxopapillary ependymoma<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDfWjqdaHK_m819mUgYZl4IYNKJe9wTv7zBNwfrZH6f9EkU2Q0h28fD4KvmCzieMv_zIKWhJrb1M9RTUP9ef3T9yo59V4kQolIIRcDVDdyCjhHFALeV5vZcqvlJKtsXbA3EtsTbgma9z8/s1600/1.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 326px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDfWjqdaHK_m819mUgYZl4IYNKJe9wTv7zBNwfrZH6f9EkU2Q0h28fD4KvmCzieMv_zIKWhJrb1M9RTUP9ef3T9yo59V4kQolIIRcDVDdyCjhHFALeV5vZcqvlJKtsXbA3EtsTbgma9z8/s400/1.png" border="0" alt=""id="BLOGGER_PHOTO_ID_5577969622918519826" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9VRfrsQqv8C_PviTvRfLLXzHx3snAGOwm4r0dbpv-nIM9C0NDEpg0YX8kpDbTCB1ClGMe5UBAQ6hXdIQQWc9N9c10azl70CPIK4I0_FX5vTWC43vSKYsREqJIId6Z0nS-fjnegAbxXSg/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 326px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9VRfrsQqv8C_PviTvRfLLXzHx3snAGOwm4r0dbpv-nIM9C0NDEpg0YX8kpDbTCB1ClGMe5UBAQ6hXdIQQWc9N9c10azl70CPIK4I0_FX5vTWC43vSKYsREqJIId6Z0nS-fjnegAbxXSg/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577969475406590738" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhpShPlfG7BtgGhTDISc77B3gD18K9SL3FfDNXaX0o3J9OK6CIwjkkZwpbBXbbeKX1_smoZqvSRZmsNLLeF0CzhBX7hsgQonpO6nLjBYfAj2jvPccZDO5-zbfdUY57AeWBtSgAuxaqpdEw/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 326px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhpShPlfG7BtgGhTDISc77B3gD18K9SL3FfDNXaX0o3J9OK6CIwjkkZwpbBXbbeKX1_smoZqvSRZmsNLLeF0CzhBX7hsgQonpO6nLjBYfAj2jvPccZDO5-zbfdUY57AeWBtSgAuxaqpdEw/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5577969397501174962" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1: Sagittal T1-weighted images reveals an isointense lobulated intradural mass at the level of the conus medullaris.<br />Figure 2: Sagittal T2-weighted images shows a hyperintense lobulated intradural mass extending from T11 through L2 with numerous small flow voids. <br />Figure 3: Sagittal T1 post-contrast images demonstrates intense enhancement of the intradural mass centered around the conus. <br /><br /><br /><span style="font-weight:bold;">Diagnosis: Myxopapillary ependymoma</span><br /><br /><br />Myxopapillary ependymoma is a slow-growing tumor arising from the ependymal cells of the filum terminale. These tumors compromise 13% of all spinal ependymomas, and they occur almost exclusively in the conus, filum terminale, and cauda equina although extradural occurence in the sacrum and presacral region has also been reported.<br /><br />The lesions tend to span two to four vertebral segments, and appear as a well-circumscribed intradural masses. In most cases the tumor is intrinsic to the conus medullaris but this is often difficult to recognize on imaging as the bulk of the mass is extramedullary. Typical MR characteristics include T1 isointensity, T2 hyperintensity, and avid enhancement on post-contrast images. As these tumors are prone to hemorrhage, a hypointensity at the tumor margin is often seen indicative of hemosiderin. Calcification and cyst formation within the mass are not infrequent.<br /><br />On radiography and CT, vertebral changes can be seen which include widened interpediculate distance, thinned pedicles, posterior vertebral scalloping, and intervertebral foraminal widening due to tumor extension.<br /><br />They are more common in males (M:F=2:1) with a mean age of 35 at diagnosis. Clinically, they present with back pain, paraparesis, radiculopathy, and occasionally bowel and bladder dysfunction. Because these symptoms can mimic those of disc herniation, there is often a delay in diagnosis. Treatment consists of surgical resection, and the prognosis is excellent with complete resection. Leptomeningeal seeding metastasis in myxopapillary variety is not as frequent as it is in classic spinal cord ependymomas and associated with poorer prognosis when present. Radiotheraphy after surgery improves outcome.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-63130784866717675702010-12-10T16:00:00.003+01:002010-12-14T20:25:58.166+01:00Capillary Telangiectasia<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEizQv2vpz21rLWYXsw4g03RQNEWKQPUhiuRhp9qfY7NcByC6Qm7IF9wyNWvSuff48hEQNS9cowZeWwaxrPCwGlsyJUKgMuVE587w9F4Ofm3a3cSfHn5BPaSQfRTH57aVnDTWaDQEgJiHrA/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 301px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEizQv2vpz21rLWYXsw4g03RQNEWKQPUhiuRhp9qfY7NcByC6Qm7IF9wyNWvSuff48hEQNS9cowZeWwaxrPCwGlsyJUKgMuVE587w9F4Ofm3a3cSfHn5BPaSQfRTH57aVnDTWaDQEgJiHrA/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549098228043890834" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhE6Q8CpD2qRY876-Q7vc6LXHw9lxCFe15uiZvxdfBPAWjeXZqN-mo3sCim23dYhbUGDkAQ6ZhhwgjlCkkV_cxTvyVXIRCGVOpABF8zmzPYsgTnT73Knv9adVyFDzq3cZQnb9JxF0gn2I4/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 311px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhE6Q8CpD2qRY876-Q7vc6LXHw9lxCFe15uiZvxdfBPAWjeXZqN-mo3sCim23dYhbUGDkAQ6ZhhwgjlCkkV_cxTvyVXIRCGVOpABF8zmzPYsgTnT73Knv9adVyFDzq3cZQnb9JxF0gn2I4/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549098191069197138" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJUqbJE6TEPrRL1J05i_zh_iIHRbsYCkX0HMnnCTHmFdtOA2aoSiWOX2aoChpaHJvNtqNVR2gaCh7JlP_EflQDL7nPtR9zkzQxslZCtBqsZdAaG-_otXT4aG8cXOr7sheTGvGvbXLUCG4/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 308px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJUqbJE6TEPrRL1J05i_zh_iIHRbsYCkX0HMnnCTHmFdtOA2aoSiWOX2aoChpaHJvNtqNVR2gaCh7JlP_EflQDL7nPtR9zkzQxslZCtBqsZdAaG-_otXT4aG8cXOr7sheTGvGvbXLUCG4/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549098139989417090" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgq9ue6cJ1vr74QVPqjni2FNl8yjyf9qo1jlGTyhhverWbBpsg-x1QbnJrIGTi7QztVJRntXiUA0uqnKVL3e2DnS2sBgaEQktONfeIN0nZ1zySPAzu8zB6T7qPPFSivgtoZ4aqRwNdRYfc/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 293px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgq9ue6cJ1vr74QVPqjni2FNl8yjyf9qo1jlGTyhhverWbBpsg-x1QbnJrIGTi7QztVJRntXiUA0uqnKVL3e2DnS2sBgaEQktONfeIN0nZ1zySPAzu8zB6T7qPPFSivgtoZ4aqRwNdRYfc/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549098091436849778" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgDOpdlJWl9vmD7u3vcoSqBjyKJJTgpjK2hyphenhyphenhfFgRwVUrnUa2QDY6G4phYlR2ALTIk_cAAagWFUpk2Zxq40jfYINRX-PWlfJADk6lLHZ7ocZ4vzecPLC3_h9ul_o1jlcG9fCYGF1HXXEAk/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 306px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgDOpdlJWl9vmD7u3vcoSqBjyKJJTgpjK2hyphenhyphenhfFgRwVUrnUa2QDY6G4phYlR2ALTIk_cAAagWFUpk2Zxq40jfYINRX-PWlfJADk6lLHZ7ocZ4vzecPLC3_h9ul_o1jlcG9fCYGF1HXXEAk/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549098046366552722" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />There is an ill-defined enhancing focus in the medial right temporal lobe on post gadolinium contrast T1-weighted imaging (Figure 4). There is no corresponding signal abnormality or mass on the precontrast T1-weighted, T2-weighted, or FLAIR images (Figure 1, Figure 2, and Figure 3, respectively). There is no mass effect. On susceptibility-weighted imaging (SWI) the lesion shows hypointensity (Figure 5).<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Capillary Telangiectasia</span><br /><br /><br />Brain capillary telangiectasias are benign vascular malformations which are often found incidentally.<br />They can be visualized by gadolinium contrast and gradient-echo susceptibility or susceptibility weighted imaging, but not through catheter angiography, and may often not be visible on conventional T1/T2, FLAIR, or diffusion-weighted imaging.<br />Often asymptomatic and usually no treatment is required.<br /><br />Brain capillary telangiectasias (BCTs) are one of four major types of vascular malformations which occur in the brain (the other three are arteriovenous malformations, cavernous malformations (cavernous angiomas), and developmental venous anomalies (venous angiomas), and represent up to 20% of all intracranial vascular lesions. BCTs consist of multiple ectatic capillaries surrounded by normal brain parenchyma and are usually devoid of calcification, gliosis, extraluminal hemorrhage, and hemosiderin-laden macrophages. BCTs are most common in the midbrain, pons, medulla, and spinal cord, but they are found throughout the central nervous system. Multiple BCTs are possible, especially in certain syndromes (e.g.; ataxia telangiectasia, Osler-Weber-Rendu, or Sturge-Weber syndrome).<br /><br />Often found incidentally, BCTs are usually benign, small in size, and rarely grow over time. They are rarely symptomatic and are not associated with any particular clinical feature but have been reported to be associated with headache, vertigo, and tinnitus.<br /><br />BCTs are relatively well visualized through susceptibility weighted imaging where they demonstrate marked signal intensity loss due to deoxyhemoglobin present in slow flowing blood. They are also well visualized through gadolinium-enhanced T1-weighted imaging sequences where they are seen as small faint lesions. BCTs are difficult to visualize through conventional T1/T2, FLAIR, or diffusion-weighted imaging and are considered to be one of the “angiographically occult vascular malformations” due to their small size, tendency to occlude, and sluggish flow.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-59853973310045691722010-12-10T16:00:00.001+01:002010-12-10T17:45:21.822+01:00Wernicke’s Encephalopathy<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0HtbDW0-84l-trkeMtPmt15W91bVl222zuQSGO8FkrE1_Mpm6NPOCgS0CCBSW31y1Hnh3_YWwrw9LyieIAG1Vp50XKsMdOOT9nXavn-0fXKjHxqX2QyopwPEvS8Cf3cbSjG2I9Y01Kvc/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0HtbDW0-84l-trkeMtPmt15W91bVl222zuQSGO8FkrE1_Mpm6NPOCgS0CCBSW31y1Hnh3_YWwrw9LyieIAG1Vp50XKsMdOOT9nXavn-0fXKjHxqX2QyopwPEvS8Cf3cbSjG2I9Y01Kvc/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549045181840901650" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgbPXNP42rnCpthut7tjb8rnzfF_NMxc2uKXZLjK3aCv8AtR4wV1dEPJskL11TY17wOq0ub74LWkT7Oz8Z4yWnW3jOPEuDTnjTBtxKMqfKXGDoHma8yXnZ-enfPjtqWs4UU5rnKuVW_7Cs/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgbPXNP42rnCpthut7tjb8rnzfF_NMxc2uKXZLjK3aCv8AtR4wV1dEPJskL11TY17wOq0ub74LWkT7Oz8Z4yWnW3jOPEuDTnjTBtxKMqfKXGDoHma8yXnZ-enfPjtqWs4UU5rnKuVW_7Cs/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549045136518235090" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfIjYHWkA8V5EcZpb552kwcMIW_xdrQWx22U4TTYTP8Blb2H0vjBRhOmySG8q0QxJDR2K9GhUq6dENlPa3XDXW8Y_t1GKzCDjJ6NF7XLYK1I6hoLIW7YpTVzynD-tC_iIT-1zLGjbsJCE/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfIjYHWkA8V5EcZpb552kwcMIW_xdrQWx22U4TTYTP8Blb2H0vjBRhOmySG8q0QxJDR2K9GhUq6dENlPa3XDXW8Y_t1GKzCDjJ6NF7XLYK1I6hoLIW7YpTVzynD-tC_iIT-1zLGjbsJCE/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549045075291941282" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbogwKF4cKqoxuRtsqycGcZinFrj3SO3Gra9kv1w1W6Eiq7a019OW91J-Sc6fQuwSNtix8OkUF4Nx0owJyVnbKVUKqLKWIZZfsvP9j4UHqWaoS1WBaBszCf-VjtiTp0qEL-kdb4gQZCGQ/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbogwKF4cKqoxuRtsqycGcZinFrj3SO3Gra9kv1w1W6Eiq7a019OW91J-Sc6fQuwSNtix8OkUF4Nx0owJyVnbKVUKqLKWIZZfsvP9j4UHqWaoS1WBaBszCf-VjtiTp0qEL-kdb4gQZCGQ/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549045029630708898" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgV2GaasQE6dnruB17A2wOSPztRZ5Jzt_ldRVECOxTrEHVFr_5NX4exkFTn1mew9hrtAOVRYcU2AtdnhEN013DBSHQ89cEZOkKNemRScy7EvF4lheVOAV-pAeWLhz8BD7rm96OS2pwWzHI/s1600/7.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgV2GaasQE6dnruB17A2wOSPztRZ5Jzt_ldRVECOxTrEHVFr_5NX4exkFTn1mew9hrtAOVRYcU2AtdnhEN013DBSHQ89cEZOkKNemRScy7EvF4lheVOAV-pAeWLhz8BD7rm96OS2pwWzHI/s400/7.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549044962582203938" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfulhCZYJKh3XXIpESRitNjeotym9PzP3ihsOUhz819Hg-YBYJhEuKDyqAr38KfpU3ivpwYmUvR9z_4E7d-u5kKbDW_wYww7ubJapMELPx3Wv5jK3sh7LGG0WhbjQ3gx3VwvQ_yfriJJE/s1600/8.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfulhCZYJKh3XXIpESRitNjeotym9PzP3ihsOUhz819Hg-YBYJhEuKDyqAr38KfpU3ivpwYmUvR9z_4E7d-u5kKbDW_wYww7ubJapMELPx3Wv5jK3sh7LGG0WhbjQ3gx3VwvQ_yfriJJE/s400/8.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549044906570524690" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />On axial images, abnormal FLAIR signal is demonstrated at the pontomedullary junction adjoining the fourth ventricle, periaqueductal gray matter in the pons and midbrain (Figure 1), the superior aspect of the mamillary bodies (Figure 2), the tissue surrounding the third ventricle and the medial thalami (Figure 3).<br />On coronal slices, abnormal FLAIR signal again appears in the mamillary bodies (Figure 8), in the tissue surrounding the third ventricle (Figure 8 and Figure 10), medial thalami (Figure 10), and periaqueductal gray matter (Figure 11).<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Wernicke’s Encephalopathy</span><br /><br /><br />Wernicke’s encephalopathy is caused by thiamine deficiency, most often seen in chronic alcohol abuse. It has also been described in anorexia nervosa, prolonged starvation, hyperemesis gravidarum, patients on long-term hemodialysis, and patients with AIDS. Patients with this condition classically present with the triad of ataxia, acute mental confusion, and oculomotor dysfunction, although a minority (16-38%) of patients with the condition present with all three elements. If the symptoms also include amnesia and confabulation, then these manifestations are called Korsakoff syndrome. Wernicke’s encephalopathy is a significantly disabling and potentially lethal condition that can be prevented and reversed if treated early with thiamine supplementation. <br /><br />On CT and MR imaging the brain demonstrates diffuse cerebral and cerebellar atrophy. Mamillary body enhancement or abnormal T2 signal may be the sole manifestation of Wernicke’s encephalopathy. Other typical MR findings include symmetric high T2 signal and variable enhancement within the periaqueductal gray matter of the midbrain, the tectal plate, the mamillothalamic tract, the thalami, and the tissue surrounding the third ventricle. The mamillary bodies may also show atrophy in patients with chronic Wernicke’s encephalopathy, though this finding can also be present in chronic alcoholic patients without Wernicke’s syndrome. Atypical changes may also be seen, almost always in non-alcoholic patients, and may include signal changes in cranial nerve nuclei, basal ganglia, cerebellum and dentate nuclei, the splenium, and frontal and parietal cortex. These atypical findings are very similar to the pattern seen in metronidazole-induced encephalopathy, and it is has been hypothesized that the two syndromes share a common metabolic pathway. The reason why these brain regions are more affected by thiamine deficiency is poorly understood, but it is speculated that they may be characterized by more intense thiamine metabolism.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-78402014034358088792010-12-07T16:00:00.004+01:002010-12-11T19:18:03.831+01:00Methotrexate neurotoxicity<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCX-QAeQLc0vHZ1-IXYz-niGDMo-cdiqtRE7UAqzD4hAjVNCHzWO8j9EsdQeo2ytGcpNY2ezw4sBZjmLVckiyh8SSr2sLzmBxZ6UFXxNOd9qldAEq2RiBO5KV0FmSoIBTfc_F9afec4To/s1600/1.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCX-QAeQLc0vHZ1-IXYz-niGDMo-cdiqtRE7UAqzD4hAjVNCHzWO8j9EsdQeo2ytGcpNY2ezw4sBZjmLVckiyh8SSr2sLzmBxZ6UFXxNOd9qldAEq2RiBO5KV0FmSoIBTfc_F9afec4To/s400/1.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489773538628786" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLveAPdUc-JdLRWp0pkI6eHO6xzeP7dnJvWPLL7ybKP0niGdnogXKqnahflUEi-aiyyHNnUjjKUEQgQWfxkXp_9bf2-tdtKqX3gS029JmC8poeyn82mUNMca0vgAONf8pxUBFfAdpdZ5U/s1600/2.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLveAPdUc-JdLRWp0pkI6eHO6xzeP7dnJvWPLL7ybKP0niGdnogXKqnahflUEi-aiyyHNnUjjKUEQgQWfxkXp_9bf2-tdtKqX3gS029JmC8poeyn82mUNMca0vgAONf8pxUBFfAdpdZ5U/s400/2.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489699792509154" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4DvY_Mnegw7fHLJyzL7FWf3k-CJ8cIRQ2719wYf4X8GpykSs6UXNyEFOIFxnjuzzpZrXVzEzYojwVScxBSwAMWHQqgBnInA1Axx50K63KYda2mKvGF0gH-By-Rpf1GS-NvMN1HDs9whc/s1600/3.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4DvY_Mnegw7fHLJyzL7FWf3k-CJ8cIRQ2719wYf4X8GpykSs6UXNyEFOIFxnjuzzpZrXVzEzYojwVScxBSwAMWHQqgBnInA1Axx50K63KYda2mKvGF0gH-By-Rpf1GS-NvMN1HDs9whc/s400/3.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489632271087218" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjIi6kSAZgYiKGPodffWIVqUjSm9LjY9QboKAzYvp2j_TdPpJ06VILnSxJ9G0uljM0UBYvyV1YzTVW7ucXlFSVgbqzx1vjruRulrPts_DY5ztVFWfNJa3oJO6-qdqJeOG73gjxUIF6NEIM/s1600/4.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjIi6kSAZgYiKGPodffWIVqUjSm9LjY9QboKAzYvp2j_TdPpJ06VILnSxJ9G0uljM0UBYvyV1YzTVW7ucXlFSVgbqzx1vjruRulrPts_DY5ztVFWfNJa3oJO6-qdqJeOG73gjxUIF6NEIM/s400/4.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489555904523026" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhi_iKZJ_PxOiMkRCPpO3h6i8n1FRJCd0pSDjkB_ZE4PP_nB87hDPkuBMm3pTgosmgZRXEAL1WYm_h-cNs4qzDtGCfwJwghSZwcHi2BKns4DWfjhloRmoc_09zx6KyRMkUw9MpYjuXHzfM/s1600/5.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhi_iKZJ_PxOiMkRCPpO3h6i8n1FRJCd0pSDjkB_ZE4PP_nB87hDPkuBMm3pTgosmgZRXEAL1WYm_h-cNs4qzDtGCfwJwghSZwcHi2BKns4DWfjhloRmoc_09zx6KyRMkUw9MpYjuXHzfM/s400/5.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489086387614210" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBU9S0SyzS_-xlNRIK7w7zp50063rD_-s52vQRegyV4qVcY4KiMqtJ_4Ey09Z_mPluOKLPZ2lpFhuuvlHo5cxmUdPqKqqMRKlhRyZ7tu3Zs-X2FTIhj3LktmCjixZjr-Rwt-rPTMC9DpM/s1600/6.JPG"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBU9S0SyzS_-xlNRIK7w7zp50063rD_-s52vQRegyV4qVcY4KiMqtJ_4Ey09Z_mPluOKLPZ2lpFhuuvlHo5cxmUdPqKqqMRKlhRyZ7tu3Zs-X2FTIhj3LktmCjixZjr-Rwt-rPTMC9DpM/s400/6.JPG" border="0" alt=""id="BLOGGER_PHOTO_ID_5549489017842875234" /></a><br /><br /><span style="font-style:italic;">Additional clinical history:</span> Patient was diagnosed with acute lymphocytic leukemia 2 months previously. He is status post induction therapy with a negative bone marrow biopsy, and is currently receiving consolidation chemotherapy with methotrexate, and presents with right upper extremity weakness.<br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />MR images of the brain demonstrate a focal area of diffusion restriction involving the left frontoparietal white matter. There is minimal associated T2/FLAIR hyperintensity. No associated enhancement. Remainder of the brain was within normal limits.<br />Imaging done four months later shows lesion has nearly resolved. <br /><br /><br /><span style="font-weight:bold;">Diagnosis: Methotrexate neurotoxicity</span><br /><br /><br /><span style="font-style:italic;">Discussion</span><br /><br />Methotrexate is a folic acid analogue. Its cytotoxic effects are carried out through inhibition of the enzyme dihydrofolate reductase, which reduces tetrahydrofolic acid levels, ultimately inhibiting cell division.<br /><br />From bone marrow cell precursors to the quickly dividing cells of the intestinal tract, methotrexate exerts its effects on all dividing cells in the body. One of its rare side effects is CNS toxicity. The decreased folate levels achieved with methotrexate have implications on metabolism of adenosine, homocysteine, and biopterin. Low folate levels lead to a subsequent decrease in S-adenosyl-methionine(SAM) concentrations. This eventually leads to chronic demyelination and neurologic symptoms.<br /><br />An additional side effect of MTX is the elevated levels of adenosine in the CSF. Adenosine is a vasodilator, which causes dilatation of cerebral vasculature resulting in neurotoxicity. The increased homocysteine levels caused by MTX have been shown to damage vascular endothelium and lead to subsequent strokes and thromboemboli. Methotrexate has also been found to cause cytotoxic edema, which is the most common cause of lesions that enhance on MRI DWI.<br /><br />The neurotoxicity caused by MTX can be immediate, acute to subacute, or delayed. Symptoms of the disease can range from headache, nausea, vomiting, and fever, to transient or permanent focal neurologic symptoms. The immediate form occurs within a day of MTX administration and presents as a chemical meningitis. The acute to subacute form presents from days to weeks after administration of MTX, and presents with seizures or focal neurologic symptoms. The delayed form presents as leukoencephalopathy and a generalized decrease in higher cognitive function.<br /><br /><br /><span style="font-style:italic;">Radiological findings</span><br /><br />A case series containing nine cases of MTX neurotoxicity revealed that lesions found in this disease tend to be focal and show up on DWI as well as T2 and FLAIR imaging. These abnormalities can continue to persist on imaging long after the symptoms have resolved. The DWI shows diffusion restriction with T2/FLAIR hyperintensity being less conspicuous. <br /><br />In another independent case study on MTX neurotoxicity, MRI demonstrated restriction diffusion with no significant T2 or FLAIR signal abnormality. Based on a combination of these imaging findings, it was determined that cytotoxic edema was likely the cause of focal neurologic symptoms on the patient, and demyelination was a less likely cause based on the MRI findings.<br /><br />A different case study had MRI findings showing subtle signal changes in the left centrum semiovale, with an obviously abnormal area of restricted diffusion, indicating the presence of increased fluid. The authors of this case also mentioned a relation between elevated choline levels in lesion areas with myelin breakdown.<br /><br />The lesion in this disease is similar in appearance to ischemic stroke, but differs in distribution. The lesions in MTX neurotoxicity can show up in many different patterns, whereas ischemic strokes often follow a vascular distribution, helping differentiate the two.<br /><br /><br /><span style="font-style:italic;">Radiology</span><br /><br /><span style="font-style:italic;">MRI:</span><br />MRI with DWI is the gold standard for diagnosis<br />Will show focal areas of demyelination and/or edema throughout the brain<br />Can be normal, even in the presence of symptoms<br />Must perform early to avoid unnecessary workup<br /><br /><br /><span style="font-style:italic;">CT:</span><br />Can be used to rule out other etiologies that may cause focal symptoms, but is not a sensitive test for demyelination and edema found with MTX neurotoxicity<br />Ultimately need MRI to make diagnosis as CT is often negative<br />Angiography<br />Not very useful as it is usually normalUnknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-89158864818366642182010-12-03T16:00:00.001+01:002010-12-10T15:02:24.341+01:00Basilar invagination secondary to rheumatoid arthritis<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjKWHgURdAVZ3XshQCt04ZpPKbP2ffg6yCcnSK5MK9TjgBz8RdQ0GRzapyZVQaSGLfniUMluMjChYRDnhasrYBFTFo5iexR2Ao8Xg9K1-zJ_Sm24osV-fLG0tFQt0BH98-K9VvnSk-BNy0/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjKWHgURdAVZ3XshQCt04ZpPKbP2ffg6yCcnSK5MK9TjgBz8RdQ0GRzapyZVQaSGLfniUMluMjChYRDnhasrYBFTFo5iexR2Ao8Xg9K1-zJ_Sm24osV-fLG0tFQt0BH98-K9VvnSk-BNy0/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549052036889539746" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8UOkPlFPkd6K4sIs4RgZNp52b-SSblYuFf6H1vCAzvDC-V2vaVVRtMQmxN3RWhm0qM97xKqNVcg5aFZbd5GnP-FSE66nODsZh7zkLywabFYxfsrrrIcZPoDOozZCAcyzti8JJ9hyphenhyphenEIjU/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 350px; height: 347px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8UOkPlFPkd6K4sIs4RgZNp52b-SSblYuFf6H1vCAzvDC-V2vaVVRtMQmxN3RWhm0qM97xKqNVcg5aFZbd5GnP-FSE66nODsZh7zkLywabFYxfsrrrIcZPoDOozZCAcyzti8JJ9hyphenhyphenEIjU/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549052828927045138" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMr5103z1ClqF0iM8kRcsOyWvq5tzUwAg9aYSNNo89ES0m-CHlaZJFSiZpDSKPDK0w6-lTxNtk39I7KGIN75s-24eCh_Kk4NtKDP1GdCH0FH1UExSw4xJlacxVhT7uJ_KbxChvibSJCNY/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhMr5103z1ClqF0iM8kRcsOyWvq5tzUwAg9aYSNNo89ES0m-CHlaZJFSiZpDSKPDK0w6-lTxNtk39I7KGIN75s-24eCh_Kk4NtKDP1GdCH0FH1UExSw4xJlacxVhT7uJ_KbxChvibSJCNY/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549051999046349202" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiSme1w6Vr967gkA0WgRVWeEKlLSgYneXErzii0E-Sm1vQjlZrLs7WvpF4Zc9pG4qZSH-LMOW6bOVYzFf2r43hNQR1k8kXHsuJlZiYzLajgHy9By7Hid2MgwfHMN1aWTW65gCCWrBA-aLg/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiSme1w6Vr967gkA0WgRVWeEKlLSgYneXErzii0E-Sm1vQjlZrLs7WvpF4Zc9pG4qZSH-LMOW6bOVYzFf2r43hNQR1k8kXHsuJlZiYzLajgHy9By7Hid2MgwfHMN1aWTW65gCCWrBA-aLg/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549051931980843618" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIKZhn7TY0naSRsz1mq3u5FL6CthlTKsCfPldNVTmBW1qK9jRX4VmPka2LJbHR-niOaUPkA3kLkblI2n3nZGRKyvo4tdWZ3M9FK_oN0EnwfrLAdhWxM1KbDL3bzVzIXV_wysbgOp3uNQ8/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIKZhn7TY0naSRsz1mq3u5FL6CthlTKsCfPldNVTmBW1qK9jRX4VmPka2LJbHR-niOaUPkA3kLkblI2n3nZGRKyvo4tdWZ3M9FK_oN0EnwfrLAdhWxM1KbDL3bzVzIXV_wysbgOp3uNQ8/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549047603646816082" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Axial and sagittal CT images demonstrate severe basilar invagination (Figure 1). The tip of the odontoid process measures 2.3 cm above Chamberlain’s line (yellow line in Figure 2). McGregor's line (red line in Figure 2) is also shown. Incidentally noted are right-sided opacified mastoid air cells (Figure 1).<br />Once again, severe basilar invagination is evident. On the sagittal T2 image the foramen magnum is narrowed and obliteration of the CSF space is noted at the C2-C3 level (Figure 3). On the axial T2 weighted image increased T2 signal (Figure 4) is seen within the cord at the C2-C3 level indicating edema versus myelomalacia.<br /><br /><br /><br /><span style="font-weight:bold;">Diagnosis: Basilar invagination (impression) secondary to rheumatoid arthritis.</span><br /><br /><br />Basilar invagination refers to a condition in which the odontoid process protrudes upward into the intracranial space. Basilar invagination may be classified as primary (congenital) or secondary (acquired). Down syndrome, Klippel-Feil syndrome and Chiari malformations are congenital causes of basilar invagination. Acquired basilar invagination, also known as basilar impression, is associated with softening of the skull base and is often due to rheumatoid arthritis, Paget disease, osteomalacia, hyperparathyroidism and osteogenesis imperfecta. Basilar invagination is probably better described as a radiologic finding rather than a diagnosis. Once the finding is identified, a cause of basilar invagination should be diligently pursued. <br /><br />Plain lateral radiographs with odontoid views, although not 100% sensitive, are often the initial study used to diagnose basilar invagination. MRI is the optimal study, which also assesses the cervicomedullary junction and cervical cord. Two craniovertebral junction lines are particularly useful in defining basilar invagination. Chamberlain’s line extends between the posterior pole of the hard palate and the posterior edge of the foramen magnum (opisthion). If the dens is >3.0 mm above this line basilar invagination is present. McGregor’s line, a modification of Chamberlain’s line was developed because the opisthion could not always be seen on plain radiographs. This line extends from the posterior pole of the hard palate to the undersurface of the occiput. If the dens extends >4.5 mm above this line basilar invagination is present.<br /><br />Clinical manifestations of basilar invagination include posterior skull pain, headache, signs and symptoms of brainstem and upper cervical cord compression or disturbances of CSF circulation causing obstructive hydrocephalus. The brainstem may be compressed at the level of the foramen magnum possibly resulting in compromise of the autonomic centers resulting in labile blood pressures, arrhythmias, or sudden death. Neurosurgery is recommended in patients that are symptomatic with concomitant MRI findings indicating compression. Although asymptomatic patients are often followed conservatively, many authors favor surgery even if no symptoms of cord compression are evident in rheumatoid patients. <br /><br />Although often appearing together, basilar invagination or impression should not be confused with platybasia; which literally means “flattening of the base of the skull”. Platybasia, which can be seen in Klippel-Feil anomalies, cleidocranial dysplasia and achondroplasia, is present when the basal angle formed by intersecting lines from the nasion to the tuberculum sellae and from the tuberculum along the clivus to the anterior aspect of the foramen magnum (basion) is greater than 143 degrees.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-47316053253953222232010-11-29T16:00:00.001+01:002010-12-10T15:06:49.781+01:00Intraventricular oligodendroglioma<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj-Etiw8N-HVbdYwnfTDAF3H7OkfwO4JP1F6Q6LqjbwRPEQe0ieogOPMD5RFVxTK97qmnOwxqxvXJZ0BCpM28Z1mKtEzRKLg6Z111a1dK0AMXq0mW0UjaAjKCkQpm0et5wbI11pdhncDcU/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 328px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj-Etiw8N-HVbdYwnfTDAF3H7OkfwO4JP1F6Q6LqjbwRPEQe0ieogOPMD5RFVxTK97qmnOwxqxvXJZ0BCpM28Z1mKtEzRKLg6Z111a1dK0AMXq0mW0UjaAjKCkQpm0et5wbI11pdhncDcU/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549054169377290194" /></a><br /><br /><br /><span style="font-style:italic;">Findings:</span><br /><br />Figure 1: Non-contrast CT shows a large rounded mass in the lateral ventricles with intermediate density and large foci of calcification within it. This is causing significant hydrocephalus with enlargement of the third ventricle.<br /><br /><br /><span style="font-weight:bold;">Intraventricular oligodendroglioma</span><br /><br /><br />Oligodentrogliomas are well differentiated, slowly growing but diffusely infiltrating cortical and subcortical tumors. Although most of them involve the frontal and frontotemporal cortex, a small proportion of them are seen in the ventricular walls (1-10%), cerebellum and exceedingly rarely within the brainstem, spinal cord and leptomeninges. No age is exempt and the peak incidence is in the 4th or 5th decades. It usually have a long standing history of symptoms and the most common being seizures and headaches.<br /><br />Intraventricular oligodentrogliomas can present with hydrocephalus. Pathologically, they are well defined, grayish-pink soft unencapsulated mass and calcification is extremely common. Focal cystic degeneration and hemorrhage are frequent findings. CSF seeding is uncommon. Histopathologically, these are moderately cellular tumors with occasional mitosis. Perinuclear halos or the "fried egg artifact" is a distinctive feature of oligodentroglioma. Majority of the "intraventricular oligodentrogliomas" described in the literature are central neurocytomas and immunohistochemistry helps to distinguish them.<br /><br />On CT, oligodentrogliomas usually have mixed density with nodular, clumped or linear tumoral calcification seen in majority (50-90%). Cystic degeneration is common. Intratumoral hemorrhage and edema is uncommon. The hemispheric lesions may expand, remodel or erode the calvarium. Enhancement is variable. On MR, oligodentrogliomas are typically heterogeneously hypointense or isointense to grey matter on T1 and heterogeneously hyperintense on T2 and FLAIR due to calcification, cystic change and hemorrhage. Nearly 50% show heterogeneous enhancement following contrast administration. Areas of calcification and hemorrhage demonstrate "blooming" on gradient echo MR sequences. No diffusion restriction on DWI.<br /><br />Surgical resection is the primary treatment of choice. Radiation therapy and chemotherapy is reserved for recurrent tumors. Local recurrence is common and hence regular surveillance is recommended.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-20002616121100529492010-11-26T16:00:00.001+01:002010-12-10T17:45:53.781+01:00Ewing sarcoma of the occipital bone<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEij2GFjp3tR5CaPncrU0JlVkuOqPk0qjLigku6-ekWcuXlTpqx3coEcWOJ02ymJEygVO81TIO4pe_L7c8VY_PyYhyphenhyphenzXVLkKzpdzvrr2K3x2vCJpTr-B_gJilQLJnNa5aTU3sdH3SQeMlu0/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 300px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEij2GFjp3tR5CaPncrU0JlVkuOqPk0qjLigku6-ekWcuXlTpqx3coEcWOJ02ymJEygVO81TIO4pe_L7c8VY_PyYhyphenhyphenzXVLkKzpdzvrr2K3x2vCJpTr-B_gJilQLJnNa5aTU3sdH3SQeMlu0/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060684883485858" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxK7vbrInpZcZklyor3MaOdHX8AFWV6iiFpK4nSIznpFCPT8R7TybCFzPkMCLwuj7RN6KWz5U1OBMaz1p_SxTFYBmYrak1rdcOXShMV_xX9GQIzDhr6AL3yBHsUsw9ecU-AbliM2RPqW8/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 300px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxK7vbrInpZcZklyor3MaOdHX8AFWV6iiFpK4nSIznpFCPT8R7TybCFzPkMCLwuj7RN6KWz5U1OBMaz1p_SxTFYBmYrak1rdcOXShMV_xX9GQIzDhr6AL3yBHsUsw9ecU-AbliM2RPqW8/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060641796844706" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAAnoW4vFHxkQ_MQNSQBra5RrvksHIU_n0s2X_B7iMXXl3HHNXfiI2VqHakWn7Y55SOvD1_SqS49_sqtYTCS0k5D0nmjvyRyWDTX0ASDgqlqq3I0Kai7JL-jB1vx0sAi1-P-XcRVOhGVI/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 270px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAAnoW4vFHxkQ_MQNSQBra5RrvksHIU_n0s2X_B7iMXXl3HHNXfiI2VqHakWn7Y55SOvD1_SqS49_sqtYTCS0k5D0nmjvyRyWDTX0ASDgqlqq3I0Kai7JL-jB1vx0sAi1-P-XcRVOhGVI/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060603484365538" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjel_pun8gs0Xrk_b6bK6sFPXB0kgj8ickp_oZf6wgvF3AW62OZ7XIFLnWf2hMRtwWGWzgmSxy0LGPy-RVVkYQlHg-JTI9gGOAp0v5ymhVUH0mz8URj53f-NZMjFhmoUsPG-PS8bJhrnLw/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 300px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjel_pun8gs0Xrk_b6bK6sFPXB0kgj8ickp_oZf6wgvF3AW62OZ7XIFLnWf2hMRtwWGWzgmSxy0LGPy-RVVkYQlHg-JTI9gGOAp0v5ymhVUH0mz8URj53f-NZMjFhmoUsPG-PS8bJhrnLw/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060552078014818" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLimiIlpOLRMSPH_ucoPxENLpCmZQ6DVIrRgusTeZgm6iLOB3ylcjCkLHpnaRL2sD9MduRzE3Wwzh1W6TPqRUe8uYc2GMPxsz5e6B0SmjA9-VCTbFESVbl9UX5wCaGLQ2JyJ7_fntfzaI/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 313px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLimiIlpOLRMSPH_ucoPxENLpCmZQ6DVIrRgusTeZgm6iLOB3ylcjCkLHpnaRL2sD9MduRzE3Wwzh1W6TPqRUe8uYc2GMPxsz5e6B0SmjA9-VCTbFESVbl9UX5wCaGLQ2JyJ7_fntfzaI/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060502973654514" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhDIunDRh1RGp9Q6m0jU8MP19qAyFdOdzPeZtc7VPtglUxMuyS1dwP4RKqtmcttKDStg50qoSuspFbd0bplmGqSdsRZGl_1cf-kThnlF-nQCTiK0H5uGPOyKGXoyt64KjChTiN2fS7eat4/s1600/6.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 300px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhDIunDRh1RGp9Q6m0jU8MP19qAyFdOdzPeZtc7VPtglUxMuyS1dwP4RKqtmcttKDStg50qoSuspFbd0bplmGqSdsRZGl_1cf-kThnlF-nQCTiK0H5uGPOyKGXoyt64KjChTiN2fS7eat4/s400/6.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549060446463943250" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1: Unenhanced CT shows a heterogeneous attenuation mass with cystic spaces in the posterior fossa.<br />Figure 2: Intense enhancement is noted after contrast administration.<br />Figure 3: Bone window section showing permeative destruction of the left occipital bone.<br />Figure 4: Axial T1 weighted image showing extra- axial mass with multiple cystic spaces.<br />Figure 5: Coronal T2 image showing the extra-axial origin clearly with mass effect on the cerebellum. The cystic spaces appear hyperintense.<br />Figure 6: Axial T1 weighted image showing intense enhancement of the mass.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Ewing sarcoma of the occipital bone</span><br /><br /><br />Ewing sarcoma is a small round-cell tumor arising from mesenchymal cells. These tumors affect children and young adults in the age group of 5-15 years. The long bones, flat bones like the scapula and the vertebrae are the most common sites. Primary Ewing sarcoma affecting the calvarium is extremely rare, making just 1% of the cases. In the skull, the tumor more often arises from the frontal and parietal bones and less common locations include ethmoid, temporal and occipital bones.<br /><br />CT scans (bone window) reveal poorly marginated permeative destructive lesion involving both inner and outer tables of the skull. The "onion peel" appearance typical of Ewing sarcoma in long bones is not seen commonly in the calvarium. The extra-dural soft tissue shows intense enhancement on contrast administration.<br /><br />MR imaging provides better soft tissue delineation of these tumors. The extra dural soft tissue appears hypointense on T1 weighted images while the cystic and necrotic areas appear hyperintense on T2 weighted images. Good contrast enhancement is noted.<br />The differential diagnosis should include rhabdomyosarcoma, metastatic neuroblastoma and lymphomas.<br /><br />Treatment is surgery followed by chemotherapy and radiation.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-70155017885657854912010-11-22T16:00:00.002+01:002010-12-10T16:15:31.281+01:00Suprasellar arachnoid cyst<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8pnPvHWVm18EkdqLJkTBT9C-AmyKAXWjBEjrp8eoM21sNMs4DPK8SQRiN9qGMPcvczdCQcQbyf1J9Kfk5VLP75dTxEhxLXJrGtgvhWNtrbDLSBZ2smvs-pICIbveLTt47Psgl6qH6kl8/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8pnPvHWVm18EkdqLJkTBT9C-AmyKAXWjBEjrp8eoM21sNMs4DPK8SQRiN9qGMPcvczdCQcQbyf1J9Kfk5VLP75dTxEhxLXJrGtgvhWNtrbDLSBZ2smvs-pICIbveLTt47Psgl6qH6kl8/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070477151066002" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEig5LXnwwU7tsm9fjyE3DJn9F_L0dKAO5b9cED2YVYHxuiMVE3Tl3ZL29R8nF9XoXFjf1h9kHvWhh0oesFwpEAf4xZSYkl1eblZmbKXs3ISwCofO9KVs8EbBGTdvvalOKitTnaOpDzvbHo/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEig5LXnwwU7tsm9fjyE3DJn9F_L0dKAO5b9cED2YVYHxuiMVE3Tl3ZL29R8nF9XoXFjf1h9kHvWhh0oesFwpEAf4xZSYkl1eblZmbKXs3ISwCofO9KVs8EbBGTdvvalOKitTnaOpDzvbHo/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070427867112754" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfGHNccPqUANupiUwOcoj5aRDBuWAqZ6SS7Y4sQB6dJawFrMRGwqumB_IOWolfwol6hz8e8fOzfHySDavOvL25X1AdM5VJjVZD_4G7O9truu64xSvw1-sb9tOWvv0hhHHdOBqCl6v6_qw/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfGHNccPqUANupiUwOcoj5aRDBuWAqZ6SS7Y4sQB6dJawFrMRGwqumB_IOWolfwol6hz8e8fOzfHySDavOvL25X1AdM5VJjVZD_4G7O9truu64xSvw1-sb9tOWvv0hhHHdOBqCl6v6_qw/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070382971878978" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOQjZl4EcuI-fEXO2eDv8xdeqDCVv41_oW0RClmwfQ6gn5IreWxV2K1sqf2SEH3OEAvkKygvdadXJBddg3OnFZp4dmW9Wm00_I8ArG73-2o2PYE94i5MwPWXHeBuMGH1FYt9q5yIz_8vQ/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOQjZl4EcuI-fEXO2eDv8xdeqDCVv41_oW0RClmwfQ6gn5IreWxV2K1sqf2SEH3OEAvkKygvdadXJBddg3OnFZp4dmW9Wm00_I8ArG73-2o2PYE94i5MwPWXHeBuMGH1FYt9q5yIz_8vQ/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070335422840434" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiy0AOfZrCcHZzRXgO0akXKNfeMqTOrg7CmDi9zjAQXOjUJJBFm7lQ98csvEtv9z9h4T7-8xc-d5cOfFVJFlQkvxvB7luUrUbI3uCuIrZx3X1gyIwig4oN4EKtBXCTNR4tarIx5yO0WyZw/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiy0AOfZrCcHZzRXgO0akXKNfeMqTOrg7CmDi9zjAQXOjUJJBFm7lQ98csvEtv9z9h4T7-8xc-d5cOfFVJFlQkvxvB7luUrUbI3uCuIrZx3X1gyIwig4oN4EKtBXCTNR4tarIx5yO0WyZw/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070282758702562" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPFdWanD-_cMR4IImyfMaROQBUqUsX1Wko_c41Xf-mmrzh42XGnYHxmgb-2HGvaHFiKr_QtHvWHh1I9X_93AtoclhUMv-IU67Ub9PGx7w-vNTpKZ8WzYYypxEdz0M8NKzVYewZjLxUSow/s1600/6.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPFdWanD-_cMR4IImyfMaROQBUqUsX1Wko_c41Xf-mmrzh42XGnYHxmgb-2HGvaHFiKr_QtHvWHh1I9X_93AtoclhUMv-IU67Ub9PGx7w-vNTpKZ8WzYYypxEdz0M8NKzVYewZjLxUSow/s400/6.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549070229630869186" /></a><br /><br /><br /><span style="font-style:italic;">Findings:</span><br /><br />Figure 1, Figure 2 and Figure 3 show severe hydrocephalus involving the lateral and third ventricles.<br />Figure 4, Figure 5, Figure 6, show a suprasellar mass lesion which follows CSF signal on all sequences, including FLAIR. <br /><br /><br /><span style="font-weight:bold;">Diagnosis: Suprasellar arachnoid cyst</span><br /><br /><br />Arachnoid cyst is the most common congenital lesion of the brain. It is typically an incidental imaging finding and is rarely symptomatic. However, in this case the size and location of the lesion in the suprasellar cistern resulted in severe obstructive hydrocephalus and precocious puberty. Both of these complications resolved following surgical drainage of the cyst.<br /><br />Arachnoid cysts arise from a splitting of the arachnoid membrane with formation of a cyst wall consisting of fibrous connective tissue. There is no epithelial lining in the wall. Expansion occurs following trapping of cerebral spinal fluid through defects in the cyst wall. Arachnoid cysts occur most commonly in the middle cranial fossa and have a 4-to-1 male-to-female ratio. Even large cysts tend to be asymptomatic. Associated clinical features in symptomatic patients include headache, calvarial bulging, intracranial hypertension, craniomegaly, developmental delay, visual loss, precocious puberty, and seizures. Treatment of arachnoid cysts is not recommended by many unless there is a clear cause and effect relationship between the cyst and symptoms as shown in this case.<br /><br />MRI is the preferred diagnostic modality for arachnoid cysts because of its ability to demonstrate the location, extent and relationship of the cyst to surrounding neurologic structures. Lesions typically have the signal intensity of CSF on all sequences, do not enhance and do not demonstrate restricted diffusion. The most important differential diagnostic consideration is between arachnoid and epidermoid cysts. Epidermoid cysts show restricted diffusion on diffusion-weighted images. In addition, unlike epidermoid cysts, arachnoid cysts show suppressed signal on fluid-attenuated inversion recovery (FLAIR) images.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-82781216033839469672010-11-19T16:00:00.000+01:002010-12-10T17:53:05.172+01:00Malignant melanoma of the uvea<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2WNLsvxdUC68zH56-fQx-J_5DcvoFVOg7ebQZQoQmEhpvgFocsfZiliQjBStrTDANxQlOJx48NZcx2MUEAxHq0ugdtIOmWUv40Asna-oCRD8vFFZ-mH74BoGXVUAxBJurL4u4nm-fhsg/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2WNLsvxdUC68zH56-fQx-J_5DcvoFVOg7ebQZQoQmEhpvgFocsfZiliQjBStrTDANxQlOJx48NZcx2MUEAxHq0ugdtIOmWUv40Asna-oCRD8vFFZ-mH74BoGXVUAxBJurL4u4nm-fhsg/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096842732784770" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiTsAJs2sKBbZ-luDZ2N4bBwHU867C-5fhUWXPXf8Asecg0zDJkfRv69asPe9_mmjPgIDOPrzuzsWhJXVr1KFzt0tbfNHGyGuasv5n-V60EcHU_1s9FxEwu7bNsIUtD9zXpgWoF7iVuMVE/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiTsAJs2sKBbZ-luDZ2N4bBwHU867C-5fhUWXPXf8Asecg0zDJkfRv69asPe9_mmjPgIDOPrzuzsWhJXVr1KFzt0tbfNHGyGuasv5n-V60EcHU_1s9FxEwu7bNsIUtD9zXpgWoF7iVuMVE/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096798364354034" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgcTjpuBMzBBVD0tNqqUuQqB5uXQ6UtYrzTA5mzH1rs9p74kCFscL9aYvLoi_UNc1aZ2cnplfis3HjporxMaXUXQOSUOZSbixBmw5G7Aild3s0QG1uOJFQv7jg4ZclQ6THAlvQvOXcCiIM/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgcTjpuBMzBBVD0tNqqUuQqB5uXQ6UtYrzTA5mzH1rs9p74kCFscL9aYvLoi_UNc1aZ2cnplfis3HjporxMaXUXQOSUOZSbixBmw5G7Aild3s0QG1uOJFQv7jg4ZclQ6THAlvQvOXcCiIM/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096752401606482" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhDK0TgtWFWRkAq6YGbDqUJcJJILafZMjuK1cPZZ4V091uYp-Qhsycw83KIidyiNP1c0hfuaFC4pAc1qcw-yFwvTyhjWOD5tqqKEVf4FufD0cYU7qG5Cff30g-TlKA-n1TsBWFKgWTBoFs/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhDK0TgtWFWRkAq6YGbDqUJcJJILafZMjuK1cPZZ4V091uYp-Qhsycw83KIidyiNP1c0hfuaFC4pAc1qcw-yFwvTyhjWOD5tqqKEVf4FufD0cYU7qG5Cff30g-TlKA-n1TsBWFKgWTBoFs/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096697298964962" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdtKhyphenhyphentMsz3-Ev6XjHCulJIuOwjqy3KWsQr_ju3d5si0oumA0_mWxqayAwEHh34Y2r1yibgDEa_HoIL6K4QyCc9-yLAKHXejcIPYk6e7x6CHDkmiKxX2nJalwHvn8EquWtCLgfnaYRunI/s1600/5.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdtKhyphenhyphentMsz3-Ev6XjHCulJIuOwjqy3KWsQr_ju3d5si0oumA0_mWxqayAwEHh34Y2r1yibgDEa_HoIL6K4QyCc9-yLAKHXejcIPYk6e7x6CHDkmiKxX2nJalwHvn8EquWtCLgfnaYRunI/s400/5.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096646415068962" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfyyZ_xcX9hi2UUPizBCUev4MYfBiMlqoq7HkX7gXSv6LEp2r3LRSfQUKmeDr-ne4HEXTjva6tvbFtpYtJxsqqsH62jdPIMb3FjAOXMEWRw-N_CJfOLvM7P5SBUnefxVh46BKk_2b4VbU/s1600/6.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfyyZ_xcX9hi2UUPizBCUev4MYfBiMlqoq7HkX7gXSv6LEp2r3LRSfQUKmeDr-ne4HEXTjva6tvbFtpYtJxsqqsH62jdPIMb3FjAOXMEWRw-N_CJfOLvM7P5SBUnefxVh46BKk_2b4VbU/s400/6.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549096580146414402" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Thin section axial fat-suppressed fast spin-echo T2-weighted imaging<br />Figure 1 and Figure 2 show a V-shaped retinal detachment pointing toward the optic nerve. There is increased T1 signal posterior to the detachment suggesting hemorrhage.<br /><br />Thin section axial fat-suppressed T1-weighted imaging<br />Figure 3 and Figure 4 show a mass arising from the nasal aspect of the right ocular globe. There is a collar button configuration to this mass, which assumes the typical configuration strongly suggesting elevation of Bruch’s membrane. The mass is near isointense to muscle on precontrast T1 and T2 weighted images. This mass extends towards the vitreous but no extension beyond the sclera is identified.<br /><br />Postcontrast fat-suppressed T1-weighted imaging<br />Figure 5 and Figure 6: The mass is near isointense to muscle on pre-contrast T1 and T2 weighted images and demonstrates prominent contrast enhancement.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Malignant melanoma of the uvea</span><br /><br /><br />Uveal melanoma is the most frequent primary intraocular malignant tumor in adults. It is rare in children. Its importance is that it is the main intraocular disease that can be fatal in adults.<br />Uveal melanoma can erupt through Bruch's Membrane. When this occurs, they develop a characteristic collar button configuration that extends through the vitreous chamber.<br />Uveal melanomas have differing MR characteristics, depending on the amount of melanin, which has paramagnetic properties. Melanomas containing a lot of melanin will demonstrate T1 hyperintensity, and markedly decreased T2 signal. However, in amelanotic or slightly melanotic melanomas, the typical MR pattern is isointense on T1, and slightly hypointense on T2. <br /><br />Uveal melanoma is the most frequent form of intraocular malignancy in adulthood (4). As the uvea is the most vascular region of the globe, it is a common site for primary and metastatic neoplasm. Uveal melanomas comprise 70% of malignant intraocular tumors. It affects approximately 5-7 out of 1,000,000 people (3). Uveal melanoma can occur in any of the three subdivisions of the uvea: the iris, ciliary body, and choroid.<br /><br />Uveal melanomas start with a flat growth profile along the choroid. With progression, they become elevated, and frequently extend through Bruch's membrane, where they can track into the subretinal space. With spread through Bruch's membrane, the melanoma can have a "mushroom shape" or "collar button" appearance that extends through the vitreous chamber. <br /><br />Uveal melanomas typically appear as a solid, well-defined mass on magnetic resonance imaging. Melanin is paramagnetic, so in melanomas containing a lot of melanin, there is increased T1 signal with markedly decreased T2 signal. This signal intensity pattern is pathognomonic for uveal melanoma, as there are no other intraocular lesions with this appearance. In low-melanin or amelanotic melanomas, Magnetic Resonance imaging is less specific, but typically shows isointense signal on T1-weight images and slightly hypointense signal on T2-weighted images. Uveal melanomas typically have moderate to strong contrast enhancement following administration of gadolinium. <br /><br />B-mode ultrasound typically shows a rounded, hypoechoic, highly vascular lesion. Retinal elevation and vitreous hemorrhage can also be seen, as these are complications of uveal melanomas. Uveal melanomas on unenhanced computed tomography appear sharply marginated, hyperattenuating, and elevated.<br /><br />Uveal melanomas also have a propensity to metastasize hematogenously, and do so most frequently to the liver. Uveal melanoma is the most common fatal intraocular disease in the adult population. <br /><br />Optimal treatment for uveal melanomas is controversial and clinical trials are ongoing. Large melanomas, typically greater than 10-mm in thickness, are usually managed with enucleation. For medium sized melanomas, 3-mm to 10-mm thick, plaque brachytherapy and external-beam radiation therapy have been accepted as alternatives to enucleation. For small lesions, less than 3-mm, routine monitoring with ultrasound is recommended as these may represent benign choroid nevi. These small lesions may also be biopsied, with a positive result placing the small melanomas into the medium melanoma treatment category.<br /><br />Prognosis is dependent on many factors. Increasing tumor pigmentation is associated with a less favorable prognosis. Additionally, increasing size, infiltration through Bruch's membrane, and retinal detachment are all associated with a poorer prognosis. In metastatic disease to the liver, the mean survival has been reported to be nine months.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-79223274200406926212010-11-15T16:00:00.000+01:002010-12-10T19:18:21.968+01:00Internal Carotid Artery Dissection<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-gRapjGs7e81FbmwuLyKRgVt7GV1-RMpm7D36wkn5kqrR_sxsywYv1fSsExW_njSQ26UB2qP0YyDDkNBoZsTOLvFKIpVP3VZtUa104Znv0l7HJfSgV9GGqEGd5TposmmLk4sp_Mpo-hY/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 333px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-gRapjGs7e81FbmwuLyKRgVt7GV1-RMpm7D36wkn5kqrR_sxsywYv1fSsExW_njSQ26UB2qP0YyDDkNBoZsTOLvFKIpVP3VZtUa104Znv0l7HJfSgV9GGqEGd5TposmmLk4sp_Mpo-hY/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549104223176169650" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjwO7dP32WXW2k9G4GH-E2i7qbfbnxGnjygyKtPzP1-n6LwoIH5e5JSMMPmif_BtBT9-jKiLMmf7X8oU-1a3u6U-YALjInGJB3SOcT8-kg5VjXOrmy8trdAIpsPniyn2_RhFF8bCpU6ITE/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 338px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjwO7dP32WXW2k9G4GH-E2i7qbfbnxGnjygyKtPzP1-n6LwoIH5e5JSMMPmif_BtBT9-jKiLMmf7X8oU-1a3u6U-YALjInGJB3SOcT8-kg5VjXOrmy8trdAIpsPniyn2_RhFF8bCpU6ITE/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549104160141965602" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgobA3e2-B_DBx9wDPJSy2mACkvwI9iHtTzB0ZEE2sVqv13J4WpfP0GxtXdqwPXzk8KNDy48LusQGsLESId9NK5bDUvLZkhFMFqWfhZjoC2ExDnivZ7FcVox5CTKhbV_IDfblZRAfvmoNs/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 377px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgobA3e2-B_DBx9wDPJSy2mACkvwI9iHtTzB0ZEE2sVqv13J4WpfP0GxtXdqwPXzk8KNDy48LusQGsLESId9NK5bDUvLZkhFMFqWfhZjoC2ExDnivZ7FcVox5CTKhbV_IDfblZRAfvmoNs/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549103847558721746" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgYYzJ72Ncs07L9rxxSxXBgufYtgzhU771W7BkENTaNvZQ13CIkxPesJrrudmyMCR-mC4-OfLxu4d64DMEWPVb9peInPi5jGt-ezvb8ZbSVDgj7bcCcWdGrogaLkeNMHxqUmE1S1a141Gk/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 379px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgYYzJ72Ncs07L9rxxSxXBgufYtgzhU771W7BkENTaNvZQ13CIkxPesJrrudmyMCR-mC4-OfLxu4d64DMEWPVb9peInPi5jGt-ezvb8ZbSVDgj7bcCcWdGrogaLkeNMHxqUmE1S1a141Gk/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549103809384927794" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8uEqn5z3PSig9w5YlUTvHgpm0-YQFMVtatOCHVVqKz59aOUO5pbF8Bo5P8qGcoD5oXe8_q6yUDFzDn98KKDbX0cNlJ4fMJ5nRhhHHBrFBZ4PaatitxKfGnCFLQbD-P5Tzk4-Pm8Ocm08/s1600/8.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 327px; height: 355px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8uEqn5z3PSig9w5YlUTvHgpm0-YQFMVtatOCHVVqKz59aOUO5pbF8Bo5P8qGcoD5oXe8_q6yUDFzDn98KKDbX0cNlJ4fMJ5nRhhHHBrFBZ4PaatitxKfGnCFLQbD-P5Tzk4-Pm8Ocm08/s400/8.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549103337507321282" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEDEKO8YHARwV7uTTkboVMSzkBkBhwHtxpIbVEYZGRUa9ekfTYMqIDXudzInHwv0IeGb4-PiWJIPMwuby3hGOYoB00HDgOnFieybIAyyuzbA0vZ9Dmg3rOgpNH_bX3Pypx3FsbCyFF_a4/s1600/9.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 131px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEDEKO8YHARwV7uTTkboVMSzkBkBhwHtxpIbVEYZGRUa9ekfTYMqIDXudzInHwv0IeGb4-PiWJIPMwuby3hGOYoB00HDgOnFieybIAyyuzbA0vZ9Dmg3rOgpNH_bX3Pypx3FsbCyFF_a4/s400/9.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549103275884359650" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrwmxlCtTKBr1AZJweQUMIbPlfLN5IrCyoq7R8MXjeFEIiyk171E2JcHg6ulfGZatxEUm2XBjMvqK1Da809DxCF8nizJr6Baq1_s4nv8Tjmbf3ezVoQrw2r3Oxzps-rsON0C7S6hzkhv8/s1600/10.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 316px; height: 327px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrwmxlCtTKBr1AZJweQUMIbPlfLN5IrCyoq7R8MXjeFEIiyk171E2JcHg6ulfGZatxEUm2XBjMvqK1Da809DxCF8nizJr6Baq1_s4nv8Tjmbf3ezVoQrw2r3Oxzps-rsON0C7S6hzkhv8/s400/10.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549103221417610738" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />CT: Multifocal areas of hypoattenuation in the right frontal lobe which are confirmed acute infarctions on MRI with diffusion weighted imaging.<br />MRI: Axial MRI DWI and matching ADC maps demonstrate multifocal areas of true restricted diffusion in the right frontal lobe indicating acute infarctions from thromboemboli secondary to more proximal right internal carotid artery dissection.<br />CTA: Sequential Axial Neck CTA images from caudal to rostral demonstrate tapering to occlusion of the right internal carotid artery just distal to the Right common carotid artery bifurcation. <br />CTA neck exam frontal, oblique, and Sagittal 3D volume rendered and Sagittal MIP images demonstrate ‘flame shaped’ tapering to occlusion of the cervical right internal carotid artery just distal to the common carotid artery bifurcation, typical of dissection. <br /><br /><br /><span style="font-weight:bold;">Diagnosis: Internal Carotid Artery Dissection</span><br /><br /><br />Carotid and vertebral artery dissection should be considered among the etiologies of brain infarct, particularly in young patients.<br />Symptoms typically include neck and face pain, headache, acute onset Horner’s syndrome, and ischemic symptoms that may occur initially or days to weeks after dissection.<br />Primarily treated with anticoagulation and aspirin.<br /><br />Spontaneous carotid dissection can occur at any age but is most frequently seen in the fifth decade of life. The most common location for dissection of the internal carotid artery is the proximal extracranial segment. While brain infarct is the most feared complication, some carotid dissections may be asymptomatic from a neurologic standpoint.<br /><br />Once thought to be a rare occurrence, spontaneous dissection of the internal carotid artery has become increasingly recognized as a cause of anterior circulation infarction, largely due to the advent of MR angiography. Predisposing factors include hypertension, Ehlers-Danlos disease, Marfan syndrome, fibromuscular dysplasia, migraine, oral contraceptives, and pharyngeal infections although most carotid dissections are seen in completely healthy individuals. A history of minor trauma is often elicited. The most studied association is chiropractic spinal manipulation, but carotid dissection has been described in various other minor traumas such as: yoga, ceiling painting, nose blowing, judo, coughing, sneezing, vomiting, and even ventilation associated with resuscitation or anesthesia. Blunt or penetrating major trauma to the head and neck is also a well-recognized cause of carotid dissection.<br /><br />The underlying abnormality in spontaneous carotid artery dissection is thought to be an expanding hematoma within the vessel wall and, as a result, on CT angiogram an intimal flap is not always seen (unlike aortic artery dissection where contrast commonly tracks into the false lumen). Patients with carotid artery dissection can present with headaches, neck pain, acute onset Horner’s syndrome, or transient ischemic attack (TIA’s) and stroke (as in our case example). The dreaded complication of vascular dissection is thromboembolic phenomenon that may occur days to weeks after the dissection.<br /><br />Imaging findings in carotid artery dissection include a tapered narrowing and occlusion of the vessel, as seen on current CTA exams with MIP images and 3D rendering. A hyperintense intramural hematoma may sometimes be seen on noncontrast axial T1 weighted imaging with fat-saturation, when blood products are in the subacute phase, representing methemoglobin. On occasion, it may also be termed the “crescent sign” because of its morphology. Signs of anterior circulation infarction can be seen on CT and MR at the time of initial presentation (as in our case). <br /><br />Treatment in uncomplicated cases usually includes anticoagulation therapy and aspirin. It is important to obtain follow up MR imaging in these patients to assess for recanalization of the vascular lumen or progressive stenosis. These patients are also more prone to development of pseudoaneurysms.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-22575101213759114702010-11-12T16:00:00.000+01:002010-12-10T19:25:41.911+01:00Idiopathic Thoracic Cord Herniation<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRcOHq_lkNuxyF4c_vXwKkSYicBOcLCGd4Bv1R9uY9BOh_iWp0qBVT49cI1lQ35h00L9ynFZL9_x-fLyePDaYR3VYHto4OrclZpxTQZiRrm9LGosjpJlsefnzzLYmGzGVZWx5MLuZyn8g/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 359px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRcOHq_lkNuxyF4c_vXwKkSYicBOcLCGd4Bv1R9uY9BOh_iWp0qBVT49cI1lQ35h00L9ynFZL9_x-fLyePDaYR3VYHto4OrclZpxTQZiRrm9LGosjpJlsefnzzLYmGzGVZWx5MLuZyn8g/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549120726129929490" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjA_6okPNVvIp_thTIEouLTPqwVsPf3A-cnWnWUYsOUYmsRwcXWiUm96BNtQaRB7OrAEU-PYn6dg87Oud0ef32HZj5Hqalx4O3NZ7Ha9A6ozYvVO6vOWixxU-K7diMw7PbdCAg-km9pokU/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 380px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjA_6okPNVvIp_thTIEouLTPqwVsPf3A-cnWnWUYsOUYmsRwcXWiUm96BNtQaRB7OrAEU-PYn6dg87Oud0ef32HZj5Hqalx4O3NZ7Ha9A6ozYvVO6vOWixxU-K7diMw7PbdCAg-km9pokU/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549120673342743906" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEha2qD4C_b3jBeNN7HcEgMSCT7TWOc4SGizpR9wFJ7AqM-TEbqI0WV3Y3ESRzX6R7SMnD6umKInN4g-hNwq5HSHYBCVvgO-90UxikTX9HvCpTDNFL1v64zhK3Ini_eJpB6F-m9twEYX6jE/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 358px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEha2qD4C_b3jBeNN7HcEgMSCT7TWOc4SGizpR9wFJ7AqM-TEbqI0WV3Y3ESRzX6R7SMnD6umKInN4g-hNwq5HSHYBCVvgO-90UxikTX9HvCpTDNFL1v64zhK3Ini_eJpB6F-m9twEYX6jE/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549120586404491474" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />These MR images demonstrate focal anterior displacement of the spinal in the mid thoracic spine. The cord (Images 1,2 and 3) appears to be either tethered anteriorly or compressed from the posterior aspect. The intradural space behind the cord is widened and has signal characteristics identical to CSF (Images 1,2 and 3).<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Idiopathic Thoracic Cord Herniation</span><br /><br /><br />Spinal cord herniation occurs when the cord herniates through a defect in the dura mater. These dural defects are typically located anteriorly or laterally, and occur most often in the mid-thoracic region. They may be idiopathic, post-traumatic or iatrogenic related to prior spinal surgery. Some have suggested that a herniated and calcified disk may cause thinning, erosion, or rupture of the dura, which may also be secondary to congenital weakening of the ventral dural fibers. The presence of free flow of cerebral spinal fluid dorsal to the herniated cord is key to differentiating a spinal cord herniation from an arachnoid cyst. Spinal cord herniation occurs most commonly in the middle-aged. Symptoms of myelopathy including chronic leg pain, gait disturbance, incontinence, and leg weakness are commonly seen and may slowly worsen over time if left untreated. The most common clinical feature reported is the Brown-Séquard syndrome consisting of hemiplegia and contralateral temperature sensation deficits and pain.<br /><br />Typical imaging findings are focal anterior displacement of the spinal cord with expansion of the dorsal subarachnoid space. The preferred imaging modality in the setting of myelopathy is MRI, which is often sufficient for making the correct diagnosis. Myelography with CT may be required in ambiguous cases and to demonstrate the exact location of the dural defect. With cord herniation, myelography reveals uninterrupted flow of contrast and the absence of a filling defect posterior to the herniated cord segment. An arachnoid cyst will present during myelography as an early filling defect posterior to the displaced cord. Contrast may fill the cyst with time, so rapid acquisition of CT-myelograpgy after the initial myelographic images is essential. Phase contrast cine MR imaging may provide similar CSF flow information, in addition to restricted cord motion.<br /><br />Treatment consists of surgically reducing the herniation by repositioning the protruding spinal cord back into the thecal sac followed by the repair of the defect in the dural mater in order to prevent recurring herniation. After surgery, symptoms typically improve and may completely resolve, even when longstanding. Patients whose symptoms are milder and non-progressive may be eligible for less invasive therapy or conservative management with monitoring.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-26653401983685672232010-11-10T16:00:00.001+01:002010-12-11T00:09:50.140+01:00Methotrexate (MTX) induced transient neurotoxicity14-year-old child with history of Acute Lymphoblastic Leukemia (ALL), on induction chemotherapy complaining of left sided weakness and facial asymmetry of acute onset.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibz8uIN1HUvz8luDbtpqOWUd_A6gkOt41iMfffah2UiOQasY3ktiet-ebSGw_GF3jfjJi44xf7p2QK2u2L7C1O927eoqD1QfGF1E9KAhOPDIcpaqhuEEhf5YjM2ztodj6dCEhGHzEKMP0/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 396px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEibz8uIN1HUvz8luDbtpqOWUd_A6gkOt41iMfffah2UiOQasY3ktiet-ebSGw_GF3jfjJi44xf7p2QK2u2L7C1O927eoqD1QfGF1E9KAhOPDIcpaqhuEEhf5YjM2ztodj6dCEhGHzEKMP0/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549194012920929970" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiLAJyuhYiOIQUT3eD_pmTf35JythxXZ9GKQBZislsGaeH-iXIdovgrEQcP8Hc5TAZu0mpfLQsc7WyRHvnPRn3KbYasSlJ9SH0u3_Z13XsDqZxxCYzFlos6bqvDH3W9zqP0QyoDkMGtmU/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 396px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgiLAJyuhYiOIQUT3eD_pmTf35JythxXZ9GKQBZislsGaeH-iXIdovgrEQcP8Hc5TAZu0mpfLQsc7WyRHvnPRn3KbYasSlJ9SH0u3_Z13XsDqZxxCYzFlos6bqvDH3W9zqP0QyoDkMGtmU/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549193967519998914" /></a><br /><br /><br />The patient was given supportive treatment and aminophylline, symptoms resolved and an MRI was repeated after 3 days.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" 10href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiBJbd7Ct2x0qfFi23nyTuJiw4DiVVl0APiA2ECCzM5GNBfO-Y-6K80GBeGf-8KpH3T-ze8bq0Or5AzczKGaVrxF1njm78nJnPPaRawHCx5tv6nT2pMfOUf6JqgK9Nm-dyPLhabpYcXPK4/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 396px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiBJbd7Ct2x0qfFi23nyTuJiw4DiVVl0APiA2ECCzM5GNBfO-Y-6K80GBeGf-8KpH3T-ze8bq0Or5AzczKGaVrxF1njm78nJnPPaRawHCx5tv6nT2pMfOUf6JqgK9Nm-dyPLhabpYcXPK4/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549193926211454962" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzVu7YhfVMcuOAfh3RRR73l20yFXNtQYoVsFv1yw1bySQpTqW6cZ-QmuYZEiva6CYN_3Sdgee-NUX1P5umk_arukVwqJl5gra2RJDPok1crFnEXWoEYtMsYqf_jFyinUG12U8vnCtp7ow/s1600/4.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 396px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzVu7YhfVMcuOAfh3RRR73l20yFXNtQYoVsFv1yw1bySQpTqW6cZ-QmuYZEiva6CYN_3Sdgee-NUX1P5umk_arukVwqJl5gra2RJDPok1crFnEXWoEYtMsYqf_jFyinUG12U8vnCtp7ow/s400/4.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549193875706021554" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Diffusion weighted images with corresponding ADC maps show restricted diffusion involving bilateral centrum semiovale (Figure 1 and Figure 2).<br />Diffusion weighted images with corresponding ADC maps, from the MRI done after clinical improvement, show resolution of abnormalities seen on DW and ADC Maps in the initial study (Figure 3 and Figure 4).<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Methotrexate (MTX) induced transient neurotoxicity</span><br /><br /><br />With improvements in antileukemic treatment there has been a steady increase in long term survivors of ALL. However a myriad of neurological complications are seen during and after treatment. These maybe broadly categorized into those related to chemotherapeutic agents, radiation therapy, coagulopathy, immunosuppression and marrow transplantation.<br /><br />Methotrexate is an essential component of treatment regimens in ALL. It can be administered both intravenously and intrathecally. Though hematologic and mucocutaneous consequences are more common, the CNS adverse effects are more worrisome. Chronic leukoencephalopathy as a result of methotrexate and radiotherapy is a well recognized complication and usuallly associated with cognitive deficits rather than focal neurologic deficits although subacuteacute encephalopathy after methotrexate may occur as well and usually presents as headache, confusion, disorientation, seizure, and focal neurologic deficit. A vast majority of patients show hemiparesis and aphasia.<br /><br />High level of adenosine is thought to be responsible for methotrexate induced toxicity. Statistically the periventricular white matter is the most common area affected. On diffusion weighted imaging these areas show increased signal intensity and hypointensity on corresponding apparent diffusion coefficient (ADC) maps. There may be no abnormality identified on T1, T2, and FLAIR sequences during the acute symptomatic phase.<br /><br />Clinical resolution is followed by the appearance of residual FLAIR hyperintensities in the involved areas, which show gradual regression. There is no established treatment, however several anecdotes report symptomatic resolution with aminophylline therapy.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-71224740930191654412010-11-08T16:00:00.000+01:002010-12-11T00:16:26.564+01:00Neuroblastoma metastases<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiaXYxwUXWiB3-kfxP_gcRw7-ZqJM7y-nzA2yV9V9lCQcoBSRJkFum18cD9j8BvvXWt14WpVd1mPIyFF8REuAFzY3XjoCm53WyHmIhyphenhyphen_4bIJgTPBbrSuUHMafRDEFnwQWBGBkJtJZCCVWs/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiaXYxwUXWiB3-kfxP_gcRw7-ZqJM7y-nzA2yV9V9lCQcoBSRJkFum18cD9j8BvvXWt14WpVd1mPIyFF8REuAFzY3XjoCm53WyHmIhyphenhyphen_4bIJgTPBbrSuUHMafRDEFnwQWBGBkJtJZCCVWs/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549195938256046418" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8RvxhyDAJG8QhNpPumWByxQvv-i9_j6-59h3-EdgKju5ZbmjuQ4FKWNwSiY5urf2kBwyJPeRC8vXNigmIgfk1HKCq-y7UFEXbjz8AfGpUNxAEXqZtcRCjbnFjaP_HJ6PvN8R0vVGItH4/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 376px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8RvxhyDAJG8QhNpPumWByxQvv-i9_j6-59h3-EdgKju5ZbmjuQ4FKWNwSiY5urf2kBwyJPeRC8vXNigmIgfk1HKCq-y7UFEXbjz8AfGpUNxAEXqZtcRCjbnFjaP_HJ6PvN8R0vVGItH4/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549195887585180274" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitVoBj2jDMzGQLSdjgVJa17nUrPyvOm-c10YAq73JkxDiG-ZG-uvp6ZZNcR27jrg4ocl3dys8kcbug6d8RQ4Un31lmxVeprQ5fXJh5O8ZVNA9B104S48iTPUiRitq97x6Ebuyoi3778kA/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 316px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitVoBj2jDMzGQLSdjgVJa17nUrPyvOm-c10YAq73JkxDiG-ZG-uvp6ZZNcR27jrg4ocl3dys8kcbug6d8RQ4Un31lmxVeprQ5fXJh5O8ZVNA9B104S48iTPUiRitq97x6Ebuyoi3778kA/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549195838538907794" /></a><br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1: Axial post gadolinium T1 weighted image showing solid enhancing parenchymal lesion in the right temporal lobe with dural and leptomeningeal disease.<br />Figure 2: Coronal post gadolinium image showing dural enhancement along the tentorium and leptomeningeal enhancement.<br />Figure 3: Axial susceptibility weighted imaging revealing the hemorrhagic nature of the lesion.<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Neuroblastoma metastases</span><br /><br /><br />Neuroblastoma metastatic to the central nervous system is extremely rare, and the reported incidence varies from 1% to 16% at recurrence. Paediatric tumors that metastasise to the brain, in order of frequency, include neuroblastoma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma and Wilm tumor.<br /><br />Risk factors for developing intracranial metastases include lumbar puncture at diagnosis, ages 2 to 3 years, bone marrow involvement, and MYCN gene amplification. Newer chemotherapeutic agents with better activity fail to penetrate the blood-brain barrier, thus facilitating a sanctuary for tumor cells within the central nervous system. As a result, the metastases evolve and become extensive before becoming clinically evident. Metastatic spread of tumor cells to central nervous system may occur either via hematogenous or cerebrospinal fluid routes and involve the neuroparenchyma, leptomeninges or dura.<br /><br />Neuroparenchymal metastases from neuroblastoma have varied appearances. They may be cystic lesions with calcified mural nodules. The wall and mural nodules show intense enhancement with contrast. Metastases may also be solid and hemorrhagic and show homogeneous enhancement. Gradient or susceptibility weighted imaging would help in detecting hemorrhagic components. Leptomeningeal and dural metastatic involvement if present indicates poor prognosis.Unknownnoreply@blogger.com0tag:blogger.com,1999:blog-2369979688209795962.post-70419761735281329002010-11-05T16:00:00.001+01:002010-12-11T00:22:59.311+01:00Pallister-Hall syndrome<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhb4ot560WQ9oQPW7bnoDI0PN65HjIp5kCMOXA-JYtB7qXrXcQi9QFSmiBVYkTN3ovRGHk7yLqfqbB0KW27No4khgM6rbx_9PoZ7Ye6guWxruqEmUbxvWKAgs_ST7jKtEePSm_SvvABu4s/s1600/1.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhb4ot560WQ9oQPW7bnoDI0PN65HjIp5kCMOXA-JYtB7qXrXcQi9QFSmiBVYkTN3ovRGHk7yLqfqbB0KW27No4khgM6rbx_9PoZ7Ye6guWxruqEmUbxvWKAgs_ST7jKtEePSm_SvvABu4s/s400/1.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549197594319312130" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhX3ZEQ3L865WIVm9NeWL95sWA2PNP58A6p2Rd6nwuBeiBY5Ky1Vnr8q_mGtrwYLtovZ91gbpehtkSwaRnFTOGv-81eWT_RpjXIjNqU4GmQiA8svkj4wrzQCNEwtjb6jKfQe_GwjZdajVg/s1600/2.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhX3ZEQ3L865WIVm9NeWL95sWA2PNP58A6p2Rd6nwuBeiBY5Ky1Vnr8q_mGtrwYLtovZ91gbpehtkSwaRnFTOGv-81eWT_RpjXIjNqU4GmQiA8svkj4wrzQCNEwtjb6jKfQe_GwjZdajVg/s400/2.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549197543116335554" /></a><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiiRdA5ENJgco15daqh46kG5pHRu2CLHUzWeSouF61T0SpwVrHV2TS_9rK_4R1-f2DOl_laeE7N71EFeul4kZujXYzDxWO_6JDFLqk5YbkZNi1O62wyTSnOkzDPlNsiFEADBzyGLDn06dc/s1600/3.ashx"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiiRdA5ENJgco15daqh46kG5pHRu2CLHUzWeSouF61T0SpwVrHV2TS_9rK_4R1-f2DOl_laeE7N71EFeul4kZujXYzDxWO_6JDFLqk5YbkZNi1O62wyTSnOkzDPlNsiFEADBzyGLDn06dc/s400/3.ashx" border="0" alt=""id="BLOGGER_PHOTO_ID_5549197485839117042" /></a><br />60-year-old female with history of a childhood seizure disorder, polydactyly, esophageal narrowing and imperforate anus presents to the ER with acute onset headache.<br /><br /><br /><span style="font-style:italic;">Findings</span><br /><br />Figure 1: T1 weighted coronal MRI demonstrates an isointense homogeneous suprasellar mass extending from the floor of the third ventricle.<br />Figure 3: T2 weighted coronal image, again demonstrating a solid homogeneous suprasellar mass with lack of any cystic components or surrounding edema.<br />Figure 3: T1 post-gadolinium coronal image shows a homogeneous mass that does not enhance<br /><br /><br /><span style="font-weight:bold;">Diagnosis: Pallister-Hall syndrome</span><br /><br /><br />Pallister Hall syndrome is an extremely rare autosomal dominant disorder first described by Judith Hall and Phillip Pallister, both pediatricians and geneticists, in 1980. The underlying mutation causing this syndrome involves the GLI3 protein which participates in gene expression and early development. The manifestations of this disorder result from both the congenital anomalies associated with the genetic mutation and from the hypothalamic hamartomas. Described congenital anomalies include but are not limited to polydactyly, imperforate anus, bifid epiglottis, and renal abnormalities. Despite variability in presentations patients consistently present with polydactyly and frequently with imperforate anus, both of which were included in this patient's medical history. <br /><br />Hypothalamic hamartomas typically involve a very specific region of the hypothalamus called the tuber cinereum, which consist of gray matter situated between the mammillary bodies and optic chiasm. This region of the brain secretes histamine in association with circadian rhythms. It is most easily identified on sagittal T1 sequences. MRI remains the best imaging modality for appreciating the position and characteristics of hamartomas. The classic image findings are a homogeneous mass in the region of the tuber cinereum which is isointense to gray matter and does not enhance after the administration of gadolinium. Following gadolinium administration, normal pituitary tissue should enhance and be easily identified separate from the tumor. Coronal sequences best demonstrate the mass extending from the floor of the third ventricle. On CT a mass which is isodense to gray matter may be seen in the suprasellar cistern, depending on the size of the lesion. The lesions typically do not calcify.<br /><br />While specific treatment does not exist for Pallister-Hall syndrome certain measures should be taken in these patients. First, due to the autosomal dominant nature of the disease genetic counseling should be provided to these patients especially if considering conception. Considering the benign nature of the hypothalamic hamartomas, regardless of any syndrome association removal should be based on severity of symptoms. Patients who elect to not have the tumor removed should be evaluated regularly for visual disturbances, neurological changes, and hormonal derangement. Furthermore, consideration should be made for routinely scanning any patient with polydactyly for hypothalamic hamartomas, especially if the patient has other congenital anomalies.Unknownnoreply@blogger.com0