Artery of Percheron infarct: a diagnostic challenge

Abstract

The artery of Percheron is a rare anatomical variation that supplies thalamus and the midbrain. A stroke in this area is a rare event. The presentation varies widely, with some bizarre disturbances, like transient episodic loss of consciousness similar to coma, somnolence, cognition and memory impairment and psychosis. We report a case of a patient who presented at the emergency department with a sudden change of consciousness. During the observation, she oscillated reactive state of consciousness with obnubilation similar to coma. The first exams were normal, which include a cranial CT of the brain, and so the patient was kept under observation. The final diagnosis was only possible 24 hours later with cranial CT where an ischaemic lesion on the Percheron territory was identified. This case highlights an unusual clinic and a difficult neuroimaging stroke diagnosis of a rare condition, that is unknown to most of the physicians.

Keywords: neuroimaging; neurology; stroke; warfarin therapy.

Figure 1

CT image, on the left CT of admission where no lesion was observed; and the two right CT images, 24 hours later, with hypodensities in the ventral portion of both thalamus with extension to the midbrain.

Figure 2

Cerebral MRI image shows subacute infarction in the bilateral thalami extending towards the ventral midbrain, compatible with a stroke of the Percheron area, and another recent ischaemic lesion between the right median cerebral artery and the right posterior cerebral artery.