Patient and aneurysm characteristics
| Patient No./ Age, y/Sex | HH Grade | CT and MR Imaging Findings | Aneurysm Site | Aneurysm Etiology | Aneurysm Progression | Rebleeding before Treatment |
|---|---|---|---|---|---|---|
| 1/46/F | 1 | SAH + IVH hydrocephalus | Left telovelotonsillar | Unknown | No | No |
| 2/34/F | 2 | SAH + IVH | Left telovelotonsillar | Dissecting | Yes | No |
| 3/52/F | 1 | SAH + IVH hydrocephalus | Right lateromedullary | Dissecting | Yes | Yes |
| 4/46/F | 0 | Aneurysm (MRA) | Right tonsillomedullary | Unknown | No | Unruptured |
| 5/60/M | 1 | SAH + IVH hydrocephalus | Left cortical | Dissecting | Yes | No |
| 6/45/M | 4 | SAH + IVH + ICH + SDH hydrocephalus | Left cortical | Dissecting | Yes | No |
| 7/52/M | 4 | SAH + IVH + ICH hydrocephalus | Right cortical | Dissecting | Yes | |
| 8/53/M | 5 | SAH + IVH + ICH hydrocephalus | Right tonsillomedullary | Dissecting | Yes | Yes |
| 9/64/F | 2 | SAH + IVH hydrocephalus | Right tonsillomedullary | Unknown | No | No |
| 10/80/F | 1 | SAH + IVH + ICH | Right cortical | Dissecting | No | |
| 11/40/M | 0 | Incidental finding (DSA) | Left tonsillomedullary | Unknown | No | Unruptured |
| 12/70/F | 1 | IVH hydrocephalus | Right telovelotonsillar | Unknown | No |
Note:—HH indicates Hunt and Hess classification; F, female; M, male; SAH, subarachnoid hemorrhage; IVH, intraventricular hemorrhage; MRA, MR angiography; ICH, intracerebral hemorrhage; SDH, subdural hemorrhage; DSA, digital subtraction angiography.