Late Reopening of Adequately Coiled Intracranial Aneurysms Frequency and Risk Factors in 400 Patients With 440 Aneurysms

Background and Purpose—In aneurysms that are adequately occluded 6 months after coiling, the risk of late reopening is largely unknown. We assessed the occurrence of late aneurysm reopening and possible risk factors. Methods—From January 1995 to June 2005, 1808 intracranial aneurysms were coiled in 1675 patients at 7 medical centers. At 6 months, 1066 aneurysms in 971 patients were adequately occluded. At mean 6.0 years after coiling, of the 971 patients, 400 patients with 440 aneurysms underwent 3 Tesla magnetic resonance angiography to assess occlusion status of the aneurysms. Proportions and corresponding 95% CI of aneurysm reopening and retreatment were calculated. Risk factors for late reopening were assessed by univariate and multivariate logistic regression analysis, and included patient sex, rupture status of aneurysms, aneurysm size ≥10 mm, and aneurysm location. Results—In 11 of 400 patients (2.8%; 95% CI, 1.4–4.9%) with 440 aneurysms (2.5%; 95% CI, 1.0–4.0%), late reopening had occurred; 3 reop...