Five-year aneurysm cumulative rupture ratea
| Aneurysms <7 mm | Aneurysms 7–12 mm | Aneurysms 13–24 mm | Aneurysms >25 mm | ||
|---|---|---|---|---|---|
| Group 1b | Group 2c | ||||
| ACA/MCA/ICA | 0 | 1.5% | 2.6% | 14.5% | 40% |
| Pcirc/PcomA | 2.5% | 3.4% | 14.5% | 18.4% | 50% |
a Data from Wiebers et al.7
b Patients who had no prior history of aneurysmal SAH.
c Patients who had a prior history of aneurysmal SAH.