Factors predicting retreatment and residual aneurysms at 1 year after endovascular coiling for ruptured cerebral aneurysms: Prospective Registry of Subarachnoid Aneurysms Treatment (PRESAT) in Japan

Introduction Endovascular treatment of cerebral aneurysms includes follow-up imaging to identify aneurysms that may need retreatment. The aim of this study was to determine predictors of incomplete aneurysm occlusion at 1 year after endovascular coiling for ruptured cerebral aneurysms. Methods In 129 patients of the Prospective Registry of Subarachnoid Aneurysms Treatment cohort, ruptured aneurysms were coiled within 14 days of onset and both initial post-coiling and 1-year follow-up digital subtraction angiography or magnetic resonance angiography were obtained. Factors predicting 1-year incomplete aneurysm occlusion (retreatment within 1-year or residual aneurysms at 1 year) were determined using multivariate logistic regression analyses. Results One-year incomplete aneurysm occlusion was identified in 59 patients, including ten patients who were retreated within 1-year post-coiling. Dome size ≥7.5 mm ( P = 0.007, odds ratio (OR) = 5.00, 95% confidence interval (CI) = 1.55–16.15), pre-treatment aneurysm re-rupture ( P = 0.023, OR = 3.50, 95% CI = 1.19–10.31), non-small size/small neck aneurysm (dome size, ≥10 mm or neck size, ≥4 mm; P = 0.022, OR = 3.26, 95% CI = 1.19–8.96), and residual aneurysms on immediate post-coiling angiograms ( P = 0.017, OR = 1.43, 95% CI = 1.07–1.93) significantly predicted incomplete aneurysm occlusion at 1-year post-coiling. Conclusions In addition to the characteristics of aneurysm and initially incomplete aneurysm occlusion, this study showed pre-treatment aneurysm re-rupture to be a predictor that favors closer imaging follow-ups for coiled aneurysms.