***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: OBJECT The goal of this study was to delineate the angioanatomical features that determine whether a patient with an unruptured middle cerebral artery ( MCA ) aneurysm is treated using endovascular coil placement or surgical clipping . METHODS Thirty consecutive patients harboring 34 unruptured MCA aneurysms were evaluated . Patients with unruptured aneurysms are managed prospect ively according to the following protocol : the primary treatment recommendation is endovascular packing with Guglielmi detachable coils ( GDCs ) . Surgical clipping is recommended after failed attempts at coil placement or in the presence of angioanatomical features that contraindicate that type of endovascular therapy . Of 34 unruptured MCA aneurysms , two ( 6 % ) were successfully embolized and 32 ( 94 % ) were clipped . Of these 32 surgically treated aneurysms , in 11 ( 34 % ) an attempt at GDC embolization had failed , whereas in 21 ( 66 % ) primary clipping was performed because of unfavorable angioanatomy . Of the 13 aneurysms treated endovascularly , two ( 15 % ) were successfully excluded , whereas GDC treatment failed in 11 ( 85 % ) . An unfavorable dome/neck ratio ( < 2 ) and an arterial branch originating at the aneurysm base were the reasons for embolization failure . CONCLUSIONS Careful evaluation of the angioanatomy of unruptured aneurysms allows selection of the most appropriate treatment . However , for unruptured MCA aneurysms , surgical clipping appears to be the most efficient treatment option . Series of unruptured aneurysms are ideal for comparing treatment results Intracranial aneurysms are common , with a prevalence of 0.5 % to 6 % in adults , according to angiography and autopsy studies .1 Most intracranial aneurysms are asymptomatic and are never detected . Some are discovered incidentally in neuroimaging studies and some produce symptoms due to compression of neighboring nerves or adjacent brain tissue . Others are detected only after they have ruptured and caused subarachnoid hemorrhage , a devastating type of stroke asso-ciated with 32 % to 67 % case fatality and 10 % to 20 % long-term dependence in survivors due to brain damage.2 To prevent subarachnoid hemorrhage , physicians have developed methods to treat aneurysms . For ruptured aneurysms , early treatment within 24 to 72 hours has been recommended because the risk of subsequent rupture is high , with approximately 20 % risk of rerupture in the first 2 weeks after subarachnoid hemorrhage.3 Each additional rupture substantially increases the risk of mortality and morbidity . Treatment has also been recommended for most unruptured aneurysms,4 although there is uncertainty about treatment of some small aneurysms < 10 mm because their risk of rupture appears low.5,6 ⇓ The American Heart Association formed this special writing group to summarize the literature and create recommendations on  endovascular therapy of ruptured and unruptured intracranial aneurysms . This statement is meant to extend previous statements on treatment of subarachnoid hemorrhage3 and on treatment of unruptured aneurysms.4 During the review , it became evident that any recommendations would be based primarily on expert opinion weighing evidence only from nonr and omized cohort studies and case series . In 1937 , Walter D and y reported the first successful surgical clipping of the neck of an aneurysm . Microsurgical techniques have steadily evolved since then , with development of a variety of surgical approaches and metal aneurysm clips . Repair of aneurysms in nearly all intracranial locations is possible by placing a clip made from a Background : Aneurysmal subarachnoid hemorrhage ( SAH ) and surgical clipping of intracranial aneurysms are associated with substantial morbidity and mortality . Objective : To compare cognitive outcome and structural damage in patients with aneurysmal SAH treated with surgical clipping or endovascular coiling .  Methods : Forty case-matched pairs of patients with aneurysmal SAH treated by surgical clipping or endovascular coiling  were prospect ively assessed by use of a battery of cognitive  tests . Twenty-three case-matched pairs underwent MRI 1 year after the procedure . Matching was based on grade of SAH on admission , location of aneurysm , age , and premorbid IQ . Results : Both groups were impaired in all cognitive domains when compared with age-matched healthy control subjects . Comparison of cognitive outcome between the two groups indicated an overall trend toward a poorer cognitive outcome in the surgical group , which achieved significance in four tests . MRI showed focal encephalomalacia exclusively in the surgical group . This group also had a significantly higher incidence of single or multiple small infa rcts within the vascular territory of the aneurysm , but both groups had similar incidence of large infa rcts and global ischemic damage . Conclusion : Endovascular treatment may cause less structural brain damage than surgery and have a more favorable cognitive outcome . However , cognitive outcome appears to be dictated primarily by the complications of SAH Recent clinical research into aneurysmal subarachnoid hemorrhage ( aSAH ) has confirmed the long-term effect of cognitive dysfunction on functional outcomes . We hypothesized that early cognitive impairment was a marker of permanent brain injury and hence predicted long-term functional outcome . Hong Kong Chinese patients with aneurysmal subarachnoid hemorrhage were evaluated prospect ively by means of the  Montreal Cognitive Assessment ( MoCA )  in the subacute phase ( 2–4 weeks after aSAH ) and by  neuropsychological evaluation of functional outcomes  in the chronic phase ( 1 year after aSAH ) . This multi-center prospect i ve observational study is registered at Clinical Trials.gov of the US National Institutes of Health ( NCT01038193 ) . One hundred and eight patients completed both the subacute and chronic phase assessment s. Cognitive dysfunction in the subacute phase independently correlated with functional outcomes at 1 year , after adjusting for age , admission clinical condition , treatment modality , motor score , and mobility in the subacute phase , but the positive predictive values remained low . MoCA-assessed cognitive impairment in the subacute phase can not accurately predict functional outcomes at 1 year . Future study should focus on underst and ing the relative importance of different components of early cognitive impairment Summary ¶ Background . After open surgery for ruptured ACoA aneurysms , several patients who have achieved a favourable neurological outcome still exhibit significant cognitive deficits . The aim of this study was to investigate the cognitive performances in patients with ACoA aneurysms su bmi tted to different therapeutic options such as endovascular treatment and surgical clipping . Methods . We evaluated 37 consecutive patients in WFNS grade I or II , who underwent an early treatment ( within 48 hours ) of a bleeding ACoA aneurysm : 20 out of 37 were surgically clipped ( group A ) and 17 were treated with endovascular coiling ( group B).These two groups were compared with 16 patients ( group C ) with subarachnoid haemorrhage and negative cerebral panangiography and with 18 volunteers ( group D ) without neurological or psychiatric disorders . All patients were neurologically intact at discharge and were in Glasgow Outcome Scale 1 at 6 months follow-up after SAH.All subjects were tested to assess selective attention , verbal , spatial and logical memory , frontal lobe executive functions , language and intelligence . Depressive symptoms and anxiety were also examined . Findings . Selective attention , verbal and spatial memory , and intelligence tests did n’t show any significant difference between the patients and the controls . Surgically treated patients showed a significant worse performance on the logical memory and on the frontal lobe executive functions compared to controls , while the endovascular group and the group C ( not treated ) showed a significant decrease only in the literal fluency score . Moreover , the surgical group showed a significant impairment in using grammatical and syntactical rules to produce sentences . No significant difference was found between the group B , C and controls . Treated patients were not significantly more depressive or anxious than controls . Interpretation . Investigation of neuropsychological deficits can show an impairment , even in patients classified as good outcome by Glasgow Outcome Scale (GOS).The frontal lobe functions and language are impaired especially in surgically treated in comparison with controls , but no significant difference was found respect to the endovascular and no treated patients ( group C ) Purpose : To compare long-term cognitive outcomes of patients treated with surgical clipping or endovascular coiling after subarachnoid haemorrhage ( SAH ) . Method : Retrospective matched cohort study assessed neuropsychological functioning at least 12 months after aneurysmal SAH treatment . Fourteen patients treated by endovascular coiling and nine patients treated by surgical clipping participated . After gaining written consent , a comprehensive neuropsychological battery was completed . St and ardised tests were employed to assess pre-morbid and current intellectual functioning ( IQ ) , attention , speed of information processing , memory and executive function as well as psychosocial functioning and affect . Results : Treatment groups were not significantly different in terms of age , pre-morbid IQ , time from injury to treatment or time since injury . A significant effect of treatment on full-scale IQ score ( p = 0.025 ) , performance IQ ( p = 0.045 ) and verbal IQ score ( p = 0.029 ) , all favouring the coiled group was observed . A medium effect size between groups difference in immediate memory ( p = 0.19 , partial η2 = 0.08 ) was also observed . No significant between group differences on attention , executive functioning and speed of information processing measures or mood and psychosocial functioning were noted . Both groups reported increased anxiety and memory , attention and speed of information processing deficits relative to normative data . Conclusions : Study findings indicate fewer cognitive deficits following endovascular coiling . Cognitive deficits in the clipped group may be due in part to the invasive nature of neurosurgical clipping . Further prospect i ve research with regard to long-term cognitive and emotional outcomes is warranted . Implication s of Rehabilitation Treatment of ruptured intracranial aneurysms by either endovascualar coiling or neurosurgical clipping can result in significant long-term physical disability as well as cognitive impairment . Observed cognitive impairment(s ) tend to be less in patients following endovascular coiling . Following ruptured aneurysm , patients with cognitive impairment report reduced health related quality of life and increased anxiety . Those with identified cognitive impairment(s ) may benefit from cognitive remediation BACKGROUND AND PURPOSE A prospect i ve study was conducted to compare the neuropsychological outcome of surgical versus endovascular treatment in patients with cerebral aneurysms . METHODS From April 2001 to 2005 , 211 patients with ruptured cerebral aneurysms were treated at the senior author 's institution . Of these 211 patients , 75 that were able and willing to undergo neuropsychological assessment 1 year after treatment of their aneurysm were enrolled in the study . Thirty-five patients were treated surgically and 40 by endovascular therapy .  St and ardized neuropsychological and personality tests were employed to assess cognitive and personality functions . One neurosurgical team using the same treatment protocol s treated all patients . RESULTS The two groups of patients did not differ significantly with respect to age , gender , concurrent diseases , Hunt and Hess grade , Fisher grade , frequency of complications , vasospasms and hydrocephalus development . No differences in performance on neuropsychological and cognitive tests ( AVLT , TMT and WAIS-III ) and personality variables and mood scales ( TCI , BDI and SMS ) were found one year postoperatively . If a full IQ as defined by WAIS-III and 1SD below the mean is considered as the main measure of cognitive deficits , 5.4 % of the sample suffered from cognitive deficits . There were no differences between clipped and coiled patients ( t=0.03 ; p=0.97 ) . CONCLUSIONS The differences in the neuropsychological assessment of patients treated by either coiling or clipping were small and non-significant . Given the small number of patients in the study , however , we suggest the need for further research with a larger sample size and the use of a r and omized design before drawing any firm conclusions OBJECT Atrophy in specific brain areas correlates with poor neuropsychological outcome  after subarachnoid hemorrhage ( SAH ) . Few studies have compared global atrophy in SAH with outcome . The authors examined the relationship between global brain atrophy , clinical factors , and outcome after SAH . METHODS This study was a post hoc exploratory analysis of the Clazosentan to Overcome Neurological Ischemia and Infa rct ion Occurring After Subarachnoid Hemorrhage ( CONSCIOUS-1 ) trial , a r and omized , double-blind , placebo-controlled trial of 413 patients with aneurysmal SAH . Patients with infa rct ions or areas of encephalomalacia on CT , and those with large clip/coil artifacts , were excluded . The 97 remaining patients underwent  CT at baseline and 6 weeks , which was analyzed using voxel-based volumetric measurements . The percentage difference in volume between time points was compared against clinical variables . The relationship with clinical outcome was modeled using univariate and multivariate analysis . RESULTS Older age , male sex , and systemic inflammatory response syndrome ( SIRS ) during intensive care stay were significantly associated with brain atrophy . Greater brain atrophy was significantly associated with poor outcome on the modified Rankin scale ( mRS ) 
    Output:
    
Coiled patients outperformed clipped patients to a greater degree in more recent publications , over longer posttreatment testing delays , and among older patients .
Higher rates of posterior circulation and MCA aneurysms were associated with smaller group differences , while ACoA rupture rates did not influence effect sizes .
Coiling of SAH may promote superior neuropsychological functioning under certain circumstances and could have applications for the specialized care of SAH patients