83 y/o woman arrived unresponsive after a fall.
Brain infarct all ct MRI
83 y/o woman with paroxysmal atrial fibrillation. Arrived unresponsive after a fall.
CT scan shows increased signal in tip of basilar artery, not seen on a prior study 2 years prior. An MRI scan was then performed (below) showing occlusion of the distal basilar artery with a large acute infarct in the distribution of the right superior cerebellar artery and a small one on the left. The posterior communicating arteries appear to reconstitute the distal tip of the basilar artery and supply the posterior cerebral arteries.




Posterior Cerebellar Artery Infact from thrombosed Basilar Artery
The superior cerebellar arteries supply superior aspect of the vermis and cerebellar hemispheres including most of the deep cerebellar white matter. If the entire tip of the basilar artery was occluded, we might see infarcts in the pons, midbrain, thalami and posterior cerebral artery distribution (which was not the case in this patient). The patient had chronic atrial fibrillation that may have been a source for an embolism to occlude the basilar/posterior cerebellar artery.