Carbon monoxide poisoning

Findings

There are fairly symmetric foci of T2 hyper intensity and restricted diffusion in the globus pallidus bilaterally.

Differential Diagnosis:
- Anoxic injury (carbon monoxide)
- Small vessel ischemic disease
- Wilson disease
- Creutzfeldt-Jakob disease
- Leigh's disease


Diagnosis: Anoxic brain injury - Carbon monoxide poisoning


Key points

Changes are typically seen in globus pallidus, but can occur in cerebral white matter (second most common), putamen, caudate, thalamus.

Imaging:
- Hypodense on CT
- T1W can be normal, hypo- or hyperintense (edema or hemorrhage)
- T2W hyperintense
- Diffusion WI restricted diffusion.

Pathologically one sees necrosis in globus pallidus with demyelination of periventricular white matter.
Presents with nonspecific symptoms of variable severity: Nausea / vomiting, headache, confusion, cognitive impairment, seizures, coma, death.
Clinically may have persistent sequelae or resolution of symptoms depending on severity and duration of exposure.
Most common cause of U.S. accidental poisoning
Can confirm diagnosis with carboxyhemoglobin level
Treatment: Hyperbaric O2 for acute cases