Bilateral thalamic infarction in a young adult: The artery of Percheron conundrum.

Artery of Percheron (AOP) infarction is a rare form of ischemic stroke resulting from the occlusion of a single arterial trunk that supplies both sides of the paramedian thalamus and the midbrain. Its occlusion can lead to bilateral and symmetrical infarctions of the paramedian thalami, and occasionally, the midbrain. Due to its atypical presentation, this condition is often diagnosed late. We report a case of a 39-year-old male with no significant medical history who arrived at the emergency department with drowsiness and confusion. During the physical examination, the patient was drowsy but responsive, with poor speech. Motor deficits in all four limbs were not apparent. Vital signs, routine blood tests, and an initial CT scan were unremarkable. The diagnosis was confirmed the following day through a subsequent CT scan and brain MRI. This case emphasizes the diagnostic challenge posed by AOP infarction and highlights the importance of considering this condition even when initial CT imaging appears normal.