***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: 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 Prospect i ve 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 Background and Purpose — We sought to better define the morbidity of endovascular Guglielmi detachable coil ( GDC ) treatment of unruptured cerebral aneurysms and to discuss its role in the prevention of subarachnoid hemorrhage . Methods — We conducted an observational study from August 1992 to June 1999 of 125 unruptured aneurysms treated with GDC in 116 patients : 91 women ( 78.4 % ) and 25 men ( 21.6 % ) , aged 30 to 78 years ( mean age , 50.6 years ) . Immediate and late clinical results were recorded for any neurological event or hemorrhage related to the treated unruptured aneurysm . Angiographic results are reported as immediate , early ( 2 to 12 months ) , intermediate ( 12 to 30 months ) , and late follow-up ( > 30 months ) . Results — Immediate angiographic results showed complete obliteration ( class 1 ) in 59 ( 47.2 % ) or residual neck ( class 2 ) in 53 aneurysms ( 42.4 % ) , leaving 6 residual aneurysms ( 4.8 % ) and 7 failures ( 5.6 % ) . Early follow-up angiograms , available in 100 treated aneurysms ( 84 % ) , revealed class 1 in 52 % and class 2 in 41 % . Intermediate angiograms , available in 53 aneurysms ( 44.5 % ) , showed class 1 in 47.2 % and class 2 in 43.4 % , while late results , available in 37 lesions ( 31.1 % ) , had class 1 and 2 in 48.6 % and 37.8 % , respectively . Six patients suffered a permanent neurological deficit at last follow-up ( 5.2 % ) , with a good outcome in 5 patients and fair outcome in 1 patient . There was no mortality . There was no aneurysmal rupture during a mean clinical follow-up of 32.1 months . Conclusions — Endovascular treatment with GDC for unruptured aneurysms is relatively safe . Its role in the prevention of aneurysmal rupture remains to be determined , preferably by a r and omized study Background Coil embolization has gained importance in the management of intracranial aneurysms over the past decade . However , the recurrence risk after embolization m and ates closer follow-up than surgical clip ligation . Currently , there is no reliable system for predicting aneurysm sac thrombosis . An aneurysm embolization grade ( AEG ) reported previously by the senior author ( EMD ) has been proposed as a tool for predicting the durability of aneurysm occlusion based on hemodynamic characteristics . Here , we present our internal validity results . Methods AEG  and Raymond – Roy Occlusion Classification ( RROC ) scores were prospect ively assigned to all aneurysms coiled from June 2008 to June 2011 . The prospect ively assigned AEG and RROC scores from the cerebral angiograms were collected for data analysis and validity assessment of the AEG system . 110 consecutive patients who had aneurysm coil embolization were included in this study . Results The post-coiling AEG significantly predicted follow-up angiographic filling characteristics . Pairwise comparisons revealed that the follow-up AEG for those initially scored ‘ A ’ ( complete obliteration ) was significantly better than the contrast-flow groups . Significant differences were also noted between contrast-stasis and contrast-flow groups . A pairwise comparison between RROC scores demonstrated that only the RROC Type 1 could be used to predict follow-up occlusion durability .  Stent placement in wide-neck aneurysms had no effect on initial AEG , RROC , or long-term occlusion durability . Packing density significantly predicted initial AEG and RROC , but had no effect on long-term occlusion . Conclusions The AEG system is uniquely based on angiographic filling characteristics of the aneurysm , and this study demonstrated its high predictive value for determining aneurysm sac thrombosis . Assigning an AEG to the aneurysm can guide the neurointerventionalist in discussion s with the patient regarding the probability of aneurysm recurrence and potential need for retreatment Background and Purpose — Our aim in this study was to assess the incidence and determining factors of angiographic recurrences after endovascular treatment of aneurysms . Methods — A retrospective analysis of all patients with selective endosaccular coil occlusion of intracranial aneurysms prospect ively collected from 1992 to 2002 was performed . There were 501 aneurysms in 466 patients ( mean±SD age , 54.20±12.54 years ; 74 % female ) . Aneurysms were acutely ruptured ( 54.1 % ) or unruptured ( 45.9 % ) . Mean±SD aneurysm size was 9.67±5.91 mm with a 4.31±1.97-mm neck . The most frequent sites were basilar bifurcation ( 27.7 % ) and carotid ophthalmic ( 18.0 % ) aneurysms . Recurrences were subjectively divided into minor and major ( ideally necessitating re-treatment ) . The most significant predictors of angiographic recurrence were determined by logistic regression . These results were confirmed by & khgr;2 , t tests , or ANOVAs followed , when appropriate , by Tukey ’s contrasts . Results — Short-term ( ≤1 year ) follow-up angiograms were available in 353 aneurysms ( 70.5 % ) and long-term ( > 1 year ) follow-up angiograms , in 277 ( 55 % ) , for a total of 383 ( 76.5 % ) followed up . Recurrences were found in 33.6 % of treated aneurysms that were followed up and that appeared at a mean±SD time of 12.31±11.33 months after treatment . Major recurrences presented in 20.7 % and appeared at a mean of 16.49±15.93 months . Three patients ( 0.8 % ) bled during a mean clinical follow-up period of 31.32±24.96 months . Variables determined to be significant predictors ( P < 0.05 ) of a recurrence included aneurysm size ≥10 mm , treatment during the acute phase of rupture , incomplete initial occlusions , and duration of follow-up . Conclusions — Long-term monitoring of patients treated by endosaccular coiling  is m and atory BACKGROUND AND PURPOSE : The purpose of this study was to analyze angiographic and clinical results before and after additional endovascular therapy in patients with previously coiled but reopened cerebral aneurysms and to identify possible risk factors for retreatment of an aneurysm . MATERIAL S AND METHODS : Follow-up with selective digital subtraction angiography was performed in 323/596 ( 54.2 % ) patients harboring 342 aneurysms with a mean follow-up time of 28.6 months . The patients were divided into 3 groups : group A , who remained stable after initial treatment ; group B , who showed minor morphologic changes ; and group C , who underwent repeat treatment . Univariate and multivariate regression analyses were performed to determine possible risk factors for aneurysmal retreatment . RESULTS : Single or multiple retreatment was performed in 33 of 323 ( 10.2 % ) patients . Retreatment of small aneurysms ( ≤10 mm ) with small necks ( ≤4 mm ) was performed in 6 of 214 aneurysms . When summarizing all other aneurysms as a “ risk group ” ( n = 128 ) , the odds ratio ( OR ) for retreatment in the “ risk group ” was 3.11 ( 95 % CI : 1.43–6.75 ; P = .004 ) . In patients with residual aneurysm after the first treatment , OR for retreatment was 3.96 ( 95 % CI : 1.48–10.65 ; P = .006 ) , whereas a neck remnant , clinical presentation , and aneurysmal localization were not predictive . We observed no result ing morbidity and mortality from the 33 retreatment procedures . CONCLUSION : In our series , the retreatment of aneurysmal recurrences was a safe procedure . The best single predictors of aneurysmal recurrence were aneurysmal anatomy ( neck width > 4 mm and diameter > 10 mm ) and the presence of a residual aneurysm after initial treatment . A limitation in our study was the significant number of patients lost to follow-up ( 22.7 % ) 
    Output:
    
RESULTS We found the Raymond scale to be predictive of retreatment , with statistically higher rates of retreatment with higher initial Raymond grade .
Furthermore , we found a higher probability of rebleeding for initial grade s 2 or 3 versus grade 1 , which approached significance .
The rebleed rates were probably affected by monitoring and treatment of recurrence .
However , although there was a trend towards higher recurrence rates with initial grade , this was not statistically significant .
The modified Raymond-Roy scale appears to provide reasonable predictive value for treated aneurysm , especially for the clinical ly more important aspects of retreatment and rebleed rates