Bilateral thalamic stroke due to occlusion of the artery of Percheron in a patient with a patent foramen ovale.

The artery of Percheron (AOP) is a rare vascular variant in which a single dominant thalamoperforating artery arises from the P1 segment and bifurcates to supply both paramedian thalami. Occlusion of this uncommon vessel results in a characteristic pattern of bilateral paramedian thalamic infarcts with or without mesencephalic infarctions. We report a case of a 37-year-old man with acute bilateral thalamic infarcts.