Artery of Percheron Infarct: ARarity Not to be Missed.

Artery of Percheron (AOP) is a rare vascular variant of posterior cerebral circulation and it supplies blood to the bilateral paramedian thalami and the rostral midbrain. Artery of Percheron infarct requires a comprehensive clinical and radiological examination. It can be easily overlooked due to normal CTfindings and wide range of differential diagnosis. Classic triad of presentation is altered mental status, memory impairment and the vertical gaze palsy. We report a case of a 66-year female who had sudden onset of severe vertigo, diplopia and ataxia. Anon-contrast CTBrain was performed which was normal. Her MRI brain with diffusion weighted images (DWI) confirmed bilateral thalamic infarcts which were initially thought to be calcifications, as usually happens with diagnosing artery of Percheron infarcts. However, by reviewing and ruling out all other possible causes of such symptoms and further review of neuroimaging, lead us to the correct diagnosis.