Tuber cinereum hamartoma

Findings

There is a 1 cm circumscribed, exophytic mass extending from the hypothalamus in the region of the tuber cinereum. It is isointense to gray matter on both T1 and T2 sequences. There is no appreciable contrast enhancement.

Differential diagnosis:
- Tuber cinereum hamartoma
- Non-enhancing (low grade) glioma
- Craniopharyngioma
- Germinoma


Diagnosis: Tuber cinereum hamartoma


Key points

Tuber cinereum hamartoma is a non-neoplastic focus of heterotopic gray matter.
Clinically, patients present with precocious puberty (due to increase leutinizing hormone releasing hormone release) and/or gelastic seizure activity.
Of pathologically proven lesions, 75% of patients will have experienced precocious puberty and 25% will have experienced seizures.
In patients with precocious puberty, 33% will be found to have tuber cinereum hamartoma.
Imaging features include small size (1 cm), round shape, non-enhancing, location near tuber cinereum (between pons/mamillary bodies and posterior aspect of the optic chiasm), iso- to hypo-intense on T1 sequences, and iso- to slightly hyper-intense to gray matter on T2. These tumors DO NOT invade adjacent structures.