Fig. 1.

Initial computed tomography image showing diffuse subarachnoid hemorrhage in the bilateral Sylvian fissure and basal cistern (a). On admission, three-dimensional rotation angiography (3D-RA) of the right vertebral artery revealed no vascular anomalies (b). Right vertebral angiography (c) and 3D-RA (d) on Day 22 revealed a microaneurysmal change (arrow) of approximately 2 mm in the dorsal basilar artery. Computed tomography angiography on Day 35 detected a microaneurysmal change (arrow) (e). However, 3D-RA on Day 73 revealed complete disappearance of the lesion (f).