Figure 1: Upper panel: Noncontrast CT Brain (a) blood in the fourth ventricle (black arrowhead) and dilatation of temporal horn of lateral ventricle suggestive of hydrocephalous. Time of flight MR angiography, (b and c) left VA terminating as a left posterior inferior cerebellar artery, two fenestrations in the basilar artery (white arrow), bilateral fetal PCA originating from ICA (white arrowhead), and hypoplastic A1 segment of right ACA. Lower panel: Noncontrast CT Brain, (d) blood in Sylvian fissure (black arrowhead). 3D DSA after right ICA injection, (e) reveals fenestration of M1 segment of the right middle cerebral artery (white arrowhead). DSA after left VA injection, and (f) large distal left vertebral artery fenestration (black arrow). CT: Computed tomography, MR: Magnetic resonance, VA: Vertebral Artery, PCA: Posterior Cerebral artery, ICA: Internal carotid artery, ACA: Anterior cerebral artery, DSA: Digital subtraction angiography