 There is mild narrowing of the distal cavernous right internal carotid artery. The intracranial internal carotid arteries are otherwise normal in course and caliber. There is a mildly hypoplastic right A1 segment. There is mild irregularity of the proximal left M1 segment. There is also mild irregularity of the proximal right M2 segments. The middle and anterior cerebral arteries are otherwise unremarkable.There is a fetal right posterior cerebral artery with absent right P1 segment. There is a hypoplastic left P1 segment with fetal type supply to the left posterior cerebral artery. There is mild-moderate focal narrowing of the proximal left P2 segment. There is additional mild focal irregularity and narrowing of the proximal posterior and anterior P2 sub-segments. The post-PICA right V4 segment is developmentally diminutive. The vertebral arteries, basilar artery, and posterior cerebral arteries are otherwise normal in course and caliber. There is no evidence of flow-limiting stenosis or aneurysm. There is a duplicated left superior cerebellar artery.
No flow-limiting stenosis or intracranial aneurysm. However, mild scattered posterior greater than anterior circulation atherosclerotic disease as detailed above. Of note, there is fetal right inferior type left supply to the PCAs.