Diagnosis: Transient alteration of awarenessClinical question: acute altered mental status in setting of hypotensionSigns and Symptoms: as above MRI of the brainSmall foci of diffusion restriction are present along the medial left cerebellar hemisphere, deep white matter of the left cerebellar hemisphere, the left occipital lobe, the left splenium of the corpus callosum the right occipital lobe adjacent to the occipital horn of the right lateral ventricle in the right thalamus. A couple more foci of diffusion restriction are present along the posterior aspect of the right centrum semiovale.There is a mild degree of periventricular and subcortical punctate hyperintense white matter lesions present identified on the FLAIR and T2 images.Normal vascular flow voids are present in the distal carotid and vertebral arteries, the basilar artery and the proximal anterior, middle and posterior cerebral arteries as well as the internal cerebral veins and superior sagittal sinus.The visualized portions of the paranasal sinuses are clear. The visualized portions of the mastoid air cells are clear. The visualized portions of the orbits are intact.MRA brain:Antegrade flow is present in the distal internal carotid arteries, the distal vertebral arteries, the basilar artery and the proximal anterior, middle and posterior cerebral arteries. There is stenosis present at the proximal intracranial portion of the vertebral arteries bilaterally as well as the distal portion of the right vertebral artery. There is also stenosis present at the proximal basilar artery just above the vertebrobasilar junction and narrowing of the mid basilar artery. There is mild narrowing of the distal left P1 segment.There is a high-grade stenosis present along the distal right internal carotid artery at the level of the communicating segment.There is no evidence for intracranial aneurysm.The anterior communicating artery is identified. The right A1 segment is hypoplastic. The left posterior communicating artery is medium-sized. The right posterior communicating artery is not readily identified.
1.There are multiple microinfarcts present mainly in the posterior circulation involving the left cerebellum, the left side of the splenium of the corpus callosum, right thalamus and right occipital lobe as well as a left occipital lobe. Additionally there are a couple microinfarcts present in the anterior circulation one of which is adjacent to the central sulcus. This would imply two separate territories are involved.2.There is vertebrobasilar stenoses present with stenosis at the intracranial vertebral arteries and the basilar artery.3.There is a high-grade stenosis present along the distal right internal carotid artery at the level of the communicating segment.