Background and purpose: The purpose of this study was to assess the incidence of late rebleeding of ruptured intracranial aneurysms treated with detachable coils.
Patients and methods: A clinical follow-up study was conducted in 393 consecutive patients with a ruptured aneurysm treated with detachable coils between January 1995 and January 2003. Late rebleeding was defined as recurrent hemorrhage from a coiled aneurysm >1 month after coiling. One patient was lost to follow-up. Total clinical follow-up of the 392 patients who were coiled for ruptured cerebral aneurysms was 18,708 months (1559 patient years; median, 48 months; mean, 47.7 months; range, 0-120 months).
Results: Four patients suffered late rebleeding from the coiled aneurysm at 8, 12, 30, and 40 months after coiling, respectively. Two of these patients died. Another patient died of probable rebleeding 4 months after coiling. The incidence of late rebleeding was 1.27% (5/393) and mortality of late rebleeding was 0.76% (3/393). The annual late rebleeding rate was 0.32%, and the annual mortality rate from late rebleeding was 0.19%. During the follow-up period, 53 coiled aneurysms in 53 patients (13%) were additionally treated: 35 aneurysms (8.9%) were additionally treated with coils, 16 aneurysms (4.1%) were additionally clipped, and 2 aneurysms (0.5%) were additionally treated with parent vessel balloon occlusion.
Conclusion: The late rebleeding rate after coiling of ruptured cerebral aneurysms is very low. Follow-up of patients with a coiled aneurysm is mandatory to identify aneurysms that need additional treatment after reopening.