Left third nerve palsy and vertical nystagmus. Brain MRI: There is no evidence of intracranial hemorrhage, mass, or acute infarct. There is extensive bilateral cerebral white matter T2 hyperintensity in the bilateral cerebral hemispheres and in the anterior pons, but the midbrain appears to be intact. There is diffuse cerebral volume loss and disproportionate cerebellar volume loss. There are prominent bilateral basal ganglia calcifications. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, paranasal sinuses, and scalp soft tissues are grossly intact.Brain MRA: There is a broad-based 5 mm wide outpouching along the supraclinoid right internal carotid artery, at the origin of the posterior communicating artery. There appears to be mild narrowing of a portion of the right middle cerebral artery M1 segment. The A1 segment of the right anterior cerebral artery is diminutive. There is focal mild narrowing of the proximal left vertebral artery C4 segment. The rest of the anterior and posterior circulation appears to be grossly intact. Neck MRA: Artifact limits the assessment of the proximal neck arteries. Apparent lack of flow-related enhancement in the bilateral V3 segments of the vertebral arteries is likely technical, since these appear to be patent on the corresponding brain MRA sequence. There appears to be mild narrowing of the proximal right internal carotid artery. Otherwise, there is no evidence of significant steno-occlusive lesions in the more distal arteries of the neck.
1. Extensive bilateral cerebral white matter T2 hyperintensity the bilateral cerebral hemispheres and in the pons are likely related to chronic small vessel ischemic disease, but the midbrain appears to be intact and there is no evidence of acute infarct.2. A 5 mm wide outpouching along the supraclinoid right internal carotid artery, at the origin of the posterior communicating artery is compatible with a wide-neck aneurysm. 3. Apparent mild narrowing of a portion of the right middle cerebral artery M1 segment, diminutive A1 segment of the right anterior cerebral artery, and focal mild narrowing of the proximal left vertebral artery C4 segment. 4. Apparent mild narrowing of the proximal right internal carotid artery. Otherwise, no evidence of significant steno-occlusive lesions in the more distal arteries of the neck.5. Diffuse cerebral volume loss and disproportionate cerebellar volume loss may be related to antiepileptic medication. 