[Recanalization of an occluded artery of Percheron causing acute bilateral thalamic infarction].

An 87-year-old woman was admitted with acute onset of disturbed consciousness. On neurological examination, both pupils were dilated and non-reactive to light. Decerebrate rigidity was present. Babinski testing was positive. CTA suggested an isolated left P1 segment occlusion. The P2 segment was supplied from the left internal carotid artery via the posterior communicating artery. MRI showed bilateral paramedian thalamic infarctions. Because occlusion of the artery of Percheron was suspected, intravenous thrombolysis was performed. Digital subtraction angiography (DSA) revealed occlusion of the left P1 segment and spontaneous recanalization before endovascular treatment. Her consciousness improved immediately. When acute bilateral thalamic infarction suggests top of the basilar artery syndrome but no basilar artery occlusion is found, occlusion of the artery of Percheron should be considered. Thrombectomy of the affected P1 segment may be needed.