Artery of percheron infarction and a very rare finding of ping pong gaze: A case report

Abstract

The Artery of Percheron (AP) is a rare anatomical variation where both paramedian thalami and the rostral midbrain receive a supply from a single perforating artery that branches off the posterior cerebral artery. When this artery becomes infarcted, this results in a unique phenomenon of bilateral thalamic as well as midbrain ischemia. A 70-year-old male showed up in the emergency department following a fall. He was oriented and awake with abnormal, slow, conjugate horizontal gaze abnormalities typical of ping pong gaze. The rest of the neurological exam was normal. Cranial computed tomography (CT) was normal initially. Magnetic resonance imaging (MRI) of the brain showed bilateral hyperintensities in the paramedian thalami. Magnetic resonance angiography (MRA) showed only 1 perforating artery originating on the P1 segment of the right posterior cerebral artery, which is consistent with an artery of Percheron infarction. Although vertical gaze palsy is frequently reported, ping-pong gaze is unusual and uncommon in this context. The unusual clinical finding of ping pong gaze can be a valuable additional feature of artery of Percheron infarction. Early MRI and MRA are critical for early diagnosis and proper treatment of this disease despite negative CT scan for better outcome.