Artery of Percheron Ischaemic Stroke: A Classic Presentation of a Rare Case

The artery of Percheron (AoP) is a rare anatomic variant, where the paramedian thalami and the rostral midbrain are supplied by an artery emerging from the P1 segment of the posterior cerebral artery. Ischaemic infarction of the artery of Percheron occurs rarely, accounting for 0.1 to 2% of all ischaemic strokes. AoP occlusion can lead to an infarction of the paramedian thalami and mesencephalon, resulting in a triad of clinical features; namely, altered mental status, vertical gaze palsy and memory impairment. A larger mesencephalon infarction can also feature oculomotor disturbances. We describe here the case of an 88-year-old patient, presenting with this triad of features. LEARNING POINTS: Neurological events such as ischaemic strokes can have a wide clinical presentation. Artery of Percheron infarction is characterized by memory impairment, vertical gaze palsy and altered mental status. Pattern recognition is fundamental for early diagnosis and optimal care.