Background and Purpose-The proportion of incompletely occluded aneurysms after coiling varies widely between studies. To assess overall outcome of coiling, we systematically reviewed the literature to determine initial occlusion, reopening, and retreatment rates of coiled aneurysms according to predefined criteria and subgroups. Methods-We searched PubMed and EMBASE (January 1999 to September 2008) for studies of Ͼ50 coiled aneurysms.Two reviewers independently extracted data. We grouped studies reporting on only ruptured aneurysms, posterior circulation aneurysms, and studies with large proportions of aneurysms Ͼ10 mm to assess possible determinants for incomplete occlusion, reopening, and retreatment. Results-Forty-six studies totalling 8161 coiled aneurysms met inclusion criteria. Immediately after coiling, 91.2% (95% CI, 90.6% to 91.9%) of the aneurysms were adequately occluded. Aneurysm reopening occurred in 20.8% (95% CI, 19.8% to 21.9%) and retreatment was performed in 10.3% (95% CI, 9.5% to 11.0%). Reopening rate was lower in studies reporting on ruptured aneurysms only compared with all studies (11.4% versus 20.8%; relative risk, 0.55; 95% CI, 0.47 to 0.64) and higher in studies focusing on posterior circulation aneurysms compared with studies with Ͼ85% anterior circulation aneurysms (22.5% versus 15.5%; relative risk, 1.5; 95% CI,1.2 to 1.7). Regression analysis showed higher retreatment rates with increasing proportion of aneurysms Ͼ10 mm (␤ϭ0.252; 95% CI, 0.073 to 0.432). We could not find a relation between reopening and type of coils used. Conclusion-At follow-up, one fifth of all coiled intracranial aneurysms shows reopening of which half is retreated.Possible risk factors for aneurysm reopening are location in the posterior circulation and size Ͼ10 mm. To confirm our findings, a meta-analysis on individual well-reported patient data is desirable. (Stroke. 2009;40:e523-e529.)

BACKGROUND AND PURPOSE:Partially thrombosed aneurysms as a distinct entity form a diverse collection of complex aneurysms characterized by organized intraluminal thrombus and solid mass. Endovascular treatment options are PVO or selective coil occlusion of the remaining lumen. We present long-term clinical and angiographic results of endovascular treatment of unruptured partially thrombosed aneurysms that presented with symptoms of mass effect.

The approach for treatment of large and fusiform intracranial aneurysms has evolved from stent-assisted coiling to treatment with flow-diverting stents. The treatment results for these stents are promising; however, early postprocedural aneurysm rupture has been described. The exact cause of rupture is unknown but might be related to intra-aneurysmal flow and pressure changes. We measured intra-aneurysmal pressure before, during, and after placement of a flow-diverting stent by using a dual-sensor guidewire. The pressure inside the aneurysm momentarily decreased during placement but was restored to baseline values within minutes. The flow-diverting stent does not seem to protect the aneurysm from the stress induced by pressure or pressure changes within the lumen.

Background and Purpose-Rates of development of de novo intracranial aneurysms and of growth of untreated additional aneurysms are largely unknown. We performed MRA in a large patient cohort with coiled aneurysms at 5-year follow-up. Methods-In 276 patients with coiled intracranial aneurysms and 5Ϯ0.5 years of follow-up MRA (totaling 1332 follow-up patient-years), additional aneurysms were classified as unchanged, grown, de novo, or incomparable with previous imaging. We calculated 5-year cumulative incidence of de novo aneurysm formation and growth of untreated aneurysms. We searched PubMed and EMBASE databases for studies assessing aneurysm development, and growth. Results-In 50 of 276 patients (18%), 75 additional aneurysms were present at follow-up MRA. Of these 75, 2 were de novo (both 3 mm), 58 were unchanged, 5 had grown from 1 to 3 mm (7.9% of 63 known additional aneurysms; 95% CI, 1.3%-14.6%), and 10 were incomparable. Five-year cumulative incidence for a de novo aneurysm developing was 0.75%. Four additional aneurysms in 3 patients were treated. Ten previous studies reported annual incidences of growth of additional aneurysms ranging from 1.51% to 22.7%, and 5 studies reported annual incidences of de novo aneurysm formation ranging from 0.3 to 1.8%. Conclusions-MRA screening of patients with coiled aneurysms within the first 5 years after treatment has a low rate of de novo aneurysm development and growth of additional aneurysms, and an even lower treatment rate. (Stroke. 2011; 42:313-318.)