66 year old Known Hypertensive with Altered Sensorium shows symmetrical bilateral posteromedial thalami and mid brain restricted diffusion foci with reduced ADC values.
Teaching Points by Dr MGK Murthy :
Thalami and mid brain are supplied by many perforating arteries (both anterior and posterior circulation) in a complex manner. The anterior circulation supplies the anteroinferior aspects of thalami and mid brain. Posterior circulation supplies the medial aspects of thalami and mid brain via P1 and P2 segments of PCAs.
Artery of Percheron is a solitary arterial trunk that arises from one of the PCAs and supplies both paramedian thalami and rostral mid brain. Occlusion of this will lead to bilateral posteromedial thalamic and rostral mid brain infarctions. Differential Diagnosis should include top of the basilar artery syndrome, which can be identified by the infarctions in the superior cerebellar arterial territories as well.