Reason: evaluate posterior circulation History: subacute left occipital stroke MRI of the brainThere is a new focus of diffusion restriciton present involving the medial left occipital lobe centered in the left cuneus but extending to the precuneus, cingulate gyrus and near the calcarine fissure.A mild degree (5-10 in the right hemisphere; 4-7 in the left) of punctate foci of diffusion restriction are present in the anterior circulation bilaterally.There is redemonstration of foci of encephalomalacia centered in the right middle frontal gyrus, right inferior parietal lobule and posterior temporal lobe, right cerebellar hemisphere and medial occipital lobes.Punctate foci of SWI hypointensity are present in the left occipital lobe adjacent to the parieto-occipital sulcus and left cuneus as well as in the right cerebellar hemisphere.There is redemonstration of a punctate T2/FLAIR hyperintense lesion in the left thalamus No abnormal enhancing mass lesions are appreciated intracranially. No intracranial hemorrhage is identified. No edema is identified within the brain parenchyma.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 demonstrate a small mucous retention cyst in the left maxillary sinus. 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 no evidence for intracranial aneurysm or cerebrovascular occlusion.The anterior communicating artery is identified and is medium size. The posterior communicating arteries are mediums size. The vertebral arteries are similar in size.MRA neck:The origins of great vessels from the aortic arch are not included on this exam. On the basis of NASCET criteria there is no significant stenosis at the carotid bifurcations. There is no significant stenosis along the course of the right vertebral artery. Findings suggest stenosis at the origin of the left vertebral artery.
1.Findings are compatible with a subacute infarction along the left occipital lobe centered in the left cuneus but extending to the precuneus, cingulate gyrus and near the calcarine fissure.2.Mild degree of microinfarcts are scattered in the anterior circulation territories bilaterally (right more than left).3.MRA on this 1.5T magnet is not able to provide adequate evaluation of the parieto-occipital arteries.4.Old lacunar infarct in the left thalamus.5.Findings suggest stenosis at the origin of the left vertebral artery.6.Multiple foci of encephalomalacia are redemonstrated intracranially (as detailed above) which are likely related to prior foci of infarction.