Male, 46 years old, with abnormal brain vasculature noted on prior MRI. Evaluate for any aneurysms. History of multiple sclerosis. The caliber of the visualized right ICA is uniformly small. As best as can be determined on MRI, it appears that the bony carotid canal is proportionately and uniformly small as well. The right MCA originates from the basilar artery, an anatomic variation. The right A1 segment is not visualized and the right ACA is supplied through the ACOM artery. No aneurysm or vascular malformation is seen. No other areas of significant vascular stenosis or occlusion are detected.
Findings are seen most compatible with congenital hypoplasia of the right ICA and basilar origin of the right MCA. No aneurysm or vascular malformation is seen.