Occlusion of artery of percheron: A rare Aetiology of Bilateral Thalamic infarct

The Artery of Percheron, a rare anatomical variant of brain vascularisation, arises from the posterior cerebral artery. Occlusion of this artery leads to bilateral paramedian thalamic infarct leads to dysfunction of central nervous system. Incidence of bilateral thalamic infarct secondary to occlusion of artery of Percheron is unknown because of its rarity. Here we report a case of 35 year old female presented with altered state of consciousness and the underlying cause was occlusion of Artery of Percheron which leads to bilateral thalamic infarct detected on MRI scanning. It showed hyperintensities on T2W1 and FLAIR, and hypointensity on T1W1, restricted to bilateral ventromedial thalami showing corresponding area of high signal intensity on diffusion weighted images and hypointensity on apparent diffusion coefficient images indicating diffusion restriction, suggestive of infarct. On further investigation magnetic resonance arteriogram (MRA) of the brain demonstrated a single common artery arising from the left P1 segment which divided into two branches distally supplying bilateral thalami. Patient became alright after 2 weeks of medical line of treatment.