Teaching NeuroImages: Bilateral hypertrophic olivary degeneration following posterior circulation stroke

A 40-year-old comatose man was brought to the hospital with a history of posterior circulation stroke 4 months earlier due to hypertension. On examination, he had spastic quadriplegia, bilateral extensor plantar reflex, and palatal myoclonus. MRI revealed enlarged olives (figure 1) and chronic infarcts involving midbrain and pons (figure 2) suggestive of hypertrophic olivary degeneration seen after 4 months of insult. Hypertrophic olivary degeneration is a transsynaptic degeneration involving interconnecting fibers of inferior olivary nucleus, red nucleus, and contralateral dentate nucleus forming the 3 corners of the Guillain-Mollaret triangle.1,2 Symmetric enlargement and T2 hyperintense olives help differentiate this entity from demyelination, tumors, and inflammatory processes.
Source: Neurology - Category: Neurology Authors: Tags: MRI, Coma, All Cerebrovascular disease/Stroke, All Education, Infarction RESIDENT AND FELLOW SECTION Source Type: research