Results of surgery for aneurysmal subarachnoid haemorrhage in northern Norway: a retrospective study with special focus on timing of surgery in a rural area

OBJECTIVES: This study reports data on time consumption before aneurysm surgery and the results of treatment in northern Norway. MATERIAL AND METHODS: A total of 279 cases were identified and included in our analysis of time span from bleeding to arrival at our department. Fifty-one patients were treated conservatively, either because of bad clinical condition or because angiography revealed no aneurysm. The remaining 228 patients were operated and included in our analysis of outcome after early aneurysm surgery. RESULTS: Among all 279 patients with aneurysmal subarachnoid haemorrhage (SAH), median time from ictus to arrival at the university hospital was 1 (0-30) day. Forty-one per cent arrived at the day of bleeding and 86% within the first 3 days after bleeding. Among the 228 patients who underwent surgical aneurysm repair, median time from bleeding to operation was 2 (0-33) days. Early aneurysm surgery (< 72 h) was performed in 146 patients (64%). Fifty patients (22%) underwent intermediate surgery (days 4-10) and 32 patients (14%) were operated later (day 11 or later). A significant association was found between Hunt and Hess (HH) grade and Glasgow Outcome Scale (GOS) score (P < 0.001). CONCLUSIONS: Most patients suffering aneurysmal SAH in northern Norway undergo early aneurysm surgery and the outcome is comparable with that obtained in other Scandinavian centres. Initial Hunt and Hess grade is a major determinant for outcome in aneurysmal subarachnoid haemorrhage.     

Patients with Supratentorial Aneurysmal Subarachnoid Hemorrhage During the Intermediate Period: Waiting or Actively Treating

Perhaps the most difficult practical decision for neurosurgeons these days is whether to secure aneurysms during the intermediate period (4–10 days) after aneurysmal subarachnoid hemorrhage (SAH). We retrospectively reviewed a series of 115 patients with a Hunt-Hess grade I-III upon admission who were admitted 4–10 days after initial supratentorial aneurysmal SAH. Patients who underwent active treatment in the intermediate period were assigned to the intermediate group (n = 49) while those who accepted delayed obliteration of a ruptured aneurysm (11–30 days) were assigned to the late group (n = 66). The demographic characteristics, size and site of aneurysms, and clinical conditions were well balanced in the two groups. There was no difference in outcome between the two groups according to the Glasgow Outcome Scale (GOS) at discharge or a six-month follow-up. Rebleeding before aneurysms obliteration was the leading factor resulting in poor outcome. In conclusion, for patients with supratentorial aneurysmal SAH who were in good clinical condition upon admission, active treatment during the intermediate period offered a good chance of a favorable outcome. An even larger number of patients from randomized clinical trials might be necessary to draw more reliable conclusions.     

Patients with Supratentorial Aneurysmal Subarachnoid Hemorrhage During the Intermediate Period: Waiting or Actively Treating

Perhaps the most difficult practical decision for neurosurgeons these days is whether to secure aneurysms during the intermediate period (4–10 days) after aneurysmal subarachnoid hemorrhage (SAH). We reviewed retrospectively a series of 115 patients with a Hunt–Hess grade I–III upon admission who were admitted 4–10 days after initial supratentorial aneurysmal SAH. Patients who underwent active treatment in the intermediate period were assigned to the intermediate group (n = 49), while those who accepted delayed obliteration of a ruptured aneurysm (11–30 days) were assigned to the late group (n = 66). The demographic characteristics, size and site of aneurysms, and clinical conditions were well balanced in the two groups. There was no difference in outcome between the two groups according to the Glasgow Outcome Scale (GOS) at discharge or a 6-month follow-up. Rebleeding before aneurysms obliteration was the leading factor resulting in poor outcome. In conclusion, for patients with supratentorial aneurysmal SAH who were in good clinical condition upon admission, active treatment during the intermediate period offered a good chance for a favorable outcome. An even larger number of patients from randomized clinical trials might be necessary to draw more reliable conclusions.     

The impact of the international subarachnoid aneurysm trial (ISAT) on the management of aneurysmal subarachnoid haemorrhage in a neurosurgical unit in the UK

OBJECTIVE: To review the changes in the management of aneurysmal subarachnoid haemorrhage (SAH) in a single neurosurgical unit in the UK, following the publication of the international subarachnoid aneurysm trial (ISAT). METHODS: The presentation, investigations, treatments and outcome data of all patients admitted with SAH to the neurosurgical unit between February 2001 and May 2003 were prospectively recorded in a database. The total period studied was split in to three blocks, around the time of publication of the ISAT in October 2002 (period 1=February-December, 2001; period 2=January-September, 2002 and period 3=October 2002 to May 2003). RESULTS: Of the 177 patients admitted with presumed SAH, 130 patients with evidence of an aneurysm on angiograms were included in the study. The mean age was 53+/-1 years, 92 (71%) patients were WFNS grade 1 or 2 and 77 (60%) were Fischer grade 2 or 3. These parameters were unchanged over the study period. Overall, 60 patients (46%) underwent a craniotomy for clipping or wrapping of aneurysm, 60 (46%) underwent endovascular embolisation of the aneurysm and 10 patients (8%) were managed conservatively. Over the study periods 1-3, the proportion of patients undergoing open surgery decreased (from 51 to 31%) while endovascular treatment of aneurysms increased (35-68%; p<0.01). Over the same time points there was a non-significant trend towards better Glasgow outcome scores at 6 months follow-up. The management mortality for all WFNS grades of patients with SAH was eight deaths (14%). The mortality in the surgical group was 3 patients (5%) and there were no deaths in the endovascular group. Over the study periods 1-3, there was a decrease in the mean total duration of hospital stay (from 23.6 to 15.5 days; p<0.05) in WFNS grade 1 and 2 patients and this was related to a shorter duration of hospital stay in the endovascular than surgical group of patients (p<0.05). The mean delay in obtaining an angiogram increased over the study periods 1-3 (1.1-2.3 days; p<0.05). CONCLUSIONS: This observational study highlights the changing pattern of management of SAH and the potential difficulties that could be encountered. The proportion of patients undergoing endovascular treatment of aneurysms has increased following the publication of the ISAT study. The associated increase in the delay in obtaining an angiogram may reflect the increased workload encountered by the neuroradiologists.     

An audit of aneurysmal subarachnoid haemorrhage: earlier resuscitation and surgery reduces inpatient stay and deaths from rebleeding.

OBJECTIVE--To audit the outcome in patients with subarachnoid haemorrhage (SAH) after a change in management strategy. METHODS--A retrospective analysis of patients with aneurysmal subarachnoid haemorrhage over a 20 month period (phase 1) was followed by a prospective analysis of patients presenting during the next 20 months (phase 2) in which a protocol driven management regime of immediate intravenous fluid resuscitation and earlier surgery was pursued. Patients in this phase were grouped into those receiving early (within four days of subarachnoid haemorrhage) and late (after four days of subarachnoid haemorrhage) surgery. In phase 1, 75 out of a total of 92 patients underwent surgery on (median) day 12. From phase 2, 109 patients out of a total of 129 underwent surgery on (median) day 4, 58 of which had their surgery within 4 days of the subarachnoid haemorrhage. Patients in each phase/group were well matched for demographic features, site of aneurysm, and severity of subarachnoid haemorrhage. RESULTS--The surgical morbidity and mortality were no different in the two phases (P < 0.92; chi2 test). The management outcomes in the two phases of the study were also no different (P < 0.52). However, there was a significant reduction in the rebleed rate in patients undergoing surgery within four days of the subarachnoid haemorrhage in phase 2 (P < 0.0001) with an associated trend towards reduced incidence of postoperative ischaemia (P = 0.06) and mortality (P = 0.11). Operating earlier in phase 2 of the trial resulted in a lower total hospital inpatient stay of 15.8 (95% CI 13.1-18.5) days for survivors compared with 25.7 (95% CI 21.6-29.8) days in the late group (P < 0.00001; t test). CONCLUSIONS--surgical morbidity and mortality seemed independent of the timing of aneurysm surgery. Early surgery within four days was associated with a highly significant reduction in rebleed rate, and in the duration of total hospital inpatient stay.     

Late epilepsy following open surgery for aneurysmal subarachnoid haemorrhage

OBJECTIVE: To determine the risk for late epilepsy (>2 weeks postoperatively) following aneurysmal subarachnoid haemorrhage (SAH) treated by early aneurysm clipping. DESIGN: Subgroup analysis of the East Anglian regional audit of SAH (1994-2000; n = 872) with 12 month follow up. Prophylactic anticonvulsants were not routinely prescribed unless there was a perioperative seizure. SUBJECTS: 472 patients with aneurysmal SAH undergoing surgical clipping of the aneurysm were studied. Patients presenting in WFNS grade V, with space occupying haematomas requiring emergency surgery, or with posterior circulation aneurysms, rebleeds, and surgery after 21 days were excluded. RESULTS: Late epilepsy occurred in 23 patients (4.9%). There was a correlation between the incidence of late epilepsy and both the presenting WFNS grade (p<0.05) (grade 1, 1.4%; grade 2, 3.8%; grade 3, 9.6%; grade 4, 12.5%) and the Glasgow outcome score at discharge (p<0.01) (good recovery, 2.2%; moderate disability, 5.0%; severe disability, 15.5%). There was no relation between the incidence of late epilepsy and sex or the site of the aneurysm. CONCLUSIONS: The low incidence of late epilepsy following open surgery for aneurysmal SAH supports the withholding of prophylactic anticonvulsants. Patients with poor WFNS grade and poor recovery after surgery are at increased risk and should be closely monitored.     

创伤性大脑前动脉瘤的早期诊断和治疗

目的探讨早期诊断和治疗创伤性大脑前动脉瘤的临床意义。方法回顾性分析9例创伤性大脑前动脉瘤患者的临床资料,分析其受伤机制、临床表现及头颅CT或MRI的特征性表现。患者早期行CTA或DSA检查,早期手术治疗,术后随访,并进行格拉斯哥预后量表(GOS)评分。结果 9例患者的动脉瘤均位于大脑前动脉分支,7例患者在动脉瘤破裂之前行手术治疗,2例患者在动脉瘤破裂后手术治疗。随访12个月,7例患者GOS评分5分,1例患者GOS评分4分,1例患者GOS评分3分。术后复查CTA,均无复发。结论对于高度怀疑创伤性大脑前动脉瘤的患者,应早期行CTA或DSA检查,早诊断、早治疗,手术治疗是其有效的治疗方法。     

颅内后循环动脉瘤的临床特征及显微外科治疗

目的 探讨颅内后循环动脉瘤的临床特征、显微外科治疗的方法及其效果.方法 对2000年1月至2008年10月手术治疗的10例颅内后循环动脉瘤的临床资料进行回顾分析.结果 动脉瘤位于基底动脉分叉部4例,大脑后动脉P1-P2交界处2例,小脑后下动脉3例,小脑前下动脉1例.以蛛网膜下腔出血为临床表现者8例,以脑神经麻痹等占位效应为表现者2例;8例行单纯动脉瘤夹闭术,2例行动脉瘤夹闭及残颈包裹术.术后随访6个月至8年,恢复良好6例,中度伤残2例,重度残疾1例,死亡1例.结论 后循环动脉瘤手术较为困难,应选择合适的入路,充分显露动脉瘤和载瘤动脉,术中尽可能保护脑干、脑干穿支动脉及脑神经,以减少手术后致死致残率.     

无蛛网膜下腔出血的破裂脑动脉瘤

目的 总结无蛛网膜下腔出血(SAH)的破裂脑动脉瘤的诊治经验.方法 对15例在起病后2 d内首次CT或MRI上表现为脑内出血(ICH),和(或)脑室内出血(IVH)、硬脑膜下血肿(SDH)和壁间出血(IMH)而无SAH的破裂脑动脉瘤患者的临床表现、影像学检查结果 、治疗方法 和预后进行回顾性分析.结果 本组首次CT或MRI检查表现为ICH者3例、IVH合并ICH者6例、SDH者1例、IVH者1例、IMH者3例和等高混合密度者1例.其中动脉瘤位于大脑中动脉6例、前交通动脉4例、后交通动脉3例、大脑前动脉1例和小脑后下动脉1例.开颅手术夹闭动脉瘤13例,血管内栓塞2例.出院时GOS评分:恢复良好8例、中残3例、重残3例和植物生存1例.本组15例占同期破裂脑动脉瘤的3.8%.结论 破裂脑动脉瘤首次CT扫描可表现为单纯ICH,和(或)IVH、SDH、IMH而无SAH,与CT扫描时间、动脉瘤的部位和指向以及出血量有关.早期控制颅内高压、及时诊断和有效处理破裂动脉瘤,是改善预后的关键.     

Circadian rhythm and aneurysmal subarachnoid hemorrhage: Is there an alarm clock for the rupture timing?

Background and purpose

Data on the temporal distribution of the bleeding time of intracranial aneurysms are limited to a few small studies. With this study, the aim was to analyze time patterns of the occurrence of aneurysmal subarachnoid hemorrhage (SAH), particularly focusing on the impact of patients' socio-demographic and clinical characteristics on the ictus timing.

Methods

The study is based on an institutional SAH cohort with 782 consecutive cases treated between January 2003 and June 2016. Data were collected on the ictus time, patients' socio-demographic and clinical characteristics, as well as the initial severity and outcome. Univariate and multivariate analyses were performed on the bleeding timeline.

Results

There were two peaks in the circadian rhythm of SAH, one in the morning (7–9 a.m.) and the other in the evening (7–9 p.m.). The strongest alterations in the bleeding time patterns were observed for weekdays, patients' age, sex and ethnicity. Individuals with chronic alcohol and painkiller consumption showed a higher bleeding peak between 1 and 3 p.m. Finally, the bleeding time showed no impact on the severity, clinically relevant complications and the outcome of SAH patients.

Conclusions

This study is one of the very few detailed analyses of the impact of specific socio-demographic, ethnic, behavioral and clinical characteristics on the rupture timing of aneurysms. Our results point to the possible relevance of the circadian rhythm for the rupture event, and therefore might be useful in the elaboration of preventive measures against aneurysm rupture.     

颅内前循环动脉瘤显微手术治疗

目的探讨颅内前循环动脉瘤显微手术治疗的疗效。方法对76例颅内前循环动脉瘤破裂引起蛛网膜下腔出血患者术前全脑DSA;;血管造影定位,在早、中期使用显微技术手术治疗,应用GOS和B;;arthel指数术后评价。结果颅内前循环动脉瘤84个,显微手术夹闭75个,包裹7个,孤立2个,GOS评分恢复良好50例;中残,但生活自理11例;重残,生活需他人服侍9例;植物生存4例。B;;arthel指数>60分60例;60～41分8例;<40分4例。死亡4例。3天内手术48例患者术后评分与4～14d内手术28例患者,差异无统计学意义(P>0.05)。结论在早、中期使用显微技术手术治疗颅内前循环动脉瘤可取得好的疗效。     

破裂颅内动脉瘤早期治疗的必要性

目的探讨破裂颅内动脉瘤早期治疗的必要性。方法首次破裂出血的颅内动脉瘤(Hunt-HessⅠ-Ⅳ级)患者62例,其中13例入院后发生再出血。采用单独开颅手术夹闭25例,单独介入栓塞27例,两者结合治疗3例。7例再出血者Hunt-Hess分级转为Ⅴ级,行保守治疗。预后评价采用GOS评分。结果本组再出血率为20.97%。再出血组13例中预后良好5例(38.5%),较差8例(61.5%);未出血组预后良好42例(85.7%),较差7例(14.3%);两组比较,P(0.05。4例术后有明确血管痉挛者1例预后良好,3例较差。早期(3日以内)治疗组21例,预后良好19例(90.48%);中期(3日～2周)治疗组24例,预后良好17例(70.83%);晚期(2周以上)治疗组10例,预后良好6例(60.00%),早期治疗组和中晚期相比,P(0.05。结论对于破裂颅内动脉瘤患者,早期及时进行干预治疗是防止再出血的关键。     

颅内后循环动脉瘤的手术治疗(附17例报告)

目的 报告颅内后循环动脉瘤的手术治疗和临床效果。方法 对17例颅内后循环动脉瘤施行显微外科手术。术中应用脑保护剂和血管临时阻断技术，1例采用低温停循环。结果 本组动脉瘤位于基底动脉分叉部及其分支12例，椎基底动脉结合部2例，小脑后下动脉3例。17例中，巨型动脉瘤7例，梭状或半梭状动脉瘤9例。10例行动脉瘤夹闭，5例行孤立，1例行包裹，1例行载瘤动脉近端阻断。手术后早期结果好11例，差5例，死亡例。经术后3个月至8年随访结果好14例，差1例，死亡1例。结论 后循环动脉瘤需要选择合适的手术入路，充分地显露动脉瘤和载瘤动脉，术中合理应用血管临时阻断和脑保护技术以及低温停循环。对于窄颈的中小型动脉瘤可以选择血管内栓塞，但对宽颈或不规则型巨大动脉瘤应采用积极的手术治疗。     

Predictors and impact of aneurysm rebleeding after subarachnoid hemorrhage

BACKGROUND: Aneurysm rebleeding has historically been an important cause of mortality after subarachnoid hemorrhage (SAH). OBJECTIVE: To describe the frequency and impact of rebleeding in the modern era of aneurysm care, which emphasizes early surgical or endovascular treatment. DESIGN: Inception cohort. SETTING: Tertiary care medical center. PATIENTS: A total of 574 patients enrolled in the Columbia University SAH Outcomes Project between August 1996 and June 2002. Early aneurysm repair was performed whenever feasible. MAIN OUTCOME MEASURES: Rebleeding was defined by prespecified clinical and radiographic criteria, excluding prehospital, intraprocedural, and postrepair events. Functional outcome was assessed at 3 months with the modified Rankin Scale. Multiple logistic regression was used to identify predictors of rebleeding, poor functional outcome, and mortality. RESULTS: Rebleeding occurred in 40 (6.9%) of the 574 patients; most cases (73%) occurred within 3 days of ictus. Hunt-Hess grade on admission (odds ratio [OR], 1.92 per grade; 95% confidence interval [CI], 1.33-2.75; P<.001) and maximal aneurysm diameter (OR, 1.07/mm; 95% CI, 1.01-1.13; P = .005) were independent predictors of rebleeding. After controlling for Hunt-Hess grade and aneurysm size, rebleeding was associated with a markedly reduced chance of survival with functional independence (modified Rankin Scale score, 相似文献   

Comparison of prognosis and complications after warning leaks in subarachnoidal hemorrhage--experience with 214 patients following aneurysm clipping

OBJECTIVES: The 'warning leak', a smaller bleeding event from an aneurysm, which sometimes occurs before an acute massive subarachnoidal hemorrhage (SAH), was first described in 1967. The present study was performed to compare the complications and prognosis for 214 patients with and without a warning leak; aneurysm clipping had been performed in all.METHODS: The interval between the warning headache and the actual SAH was calculated. The following complications were examined: preoperative hemorrhage, intra-operative rupture of the aneurysm, postoperative re-bleeding, symptomatic vasospasm, shunt-requiring hydrocephalus, ventriculitis, postoperative wound infection, and outcome according to the Glasgow Outcome Scale (GOS).RESULTS: Sixty-seven (31%) out of the 214 patients had a warning leak with a median distance of 11 days before suffering from major SAH. Preoperative angiographic vasospasms occurred more frequently in the group with a warning bleeding (22.4 versus 6.1%; p<0.05), which means that the warning leaks induce vascular reactions similar to SAH. The outcome of both groups after a mean follow-up time of 22 months did not show any difference. But 30 out of the 67 patients with a warning leak were graded H&H III-V at admission to hospital after a major SAH. The overall outcome for patients graded H&H I and II was in 92% favorable, compared with only a 54% favorable outcome for H&H III-V patients. Long-term outcome in the warning leak group was not impaired by angiographically proven vasospasm.DISCUSSION: To give patients the chance to start their treatment in a better clinical condition it is important to recognize the early warning signs.     

Current strategies for the management of aneurysmal subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) from a ruptured intracranial aneurysm represents a major health issue. Although most people who experience an aneurysmal SAH survive to be admitted to a hospital, less than one third of these patients ever return to their premorbid status. Clearly, morbidity of this magnitude demands reevaluation of the clinical approach to this problem. This article reviews the natural history of aneurysmal SAH, and examines the current therapeutic strategies that have been suggested to improve the outcome. Careful evaluation of the existing data suggests that early aneurysm surgery and aggressive postoperative volume expansion therapy constitute the best presently available approach to patients with ruptured intracranial aneurysms.     

The outcome of early surgical management of ruptured posterior circulation aneurysms

Abstract

Since 7990, early surgery within 3 days following subarachnoid hemorrhage has been performed routinely in our hospital even for ruptured posterior circulation aneurysms. Our experience with early surgical management of 25 patients with posterior circulation aneurysms, including two patients who underwent endovascular surgery, is reported. Fourteen patients had an aneurysm on the basilar, the posterior cerebral or superior cerebellar artery (BAJ, and 77 patients had an aneurysm on the vertebral or posterior inferior cerebellar artery (VA). The mortality and morbidity of the BA group were 7% and 29%, respectively, and those of the VA group were 27% and 9%, respectively. In BA, the incidence ofsymptomatic vasospasm and hydrocephalus was definitely high compared with VA, and the outcome in elderly patients was significantly unfavorable. Early surgery for posterior circulation aneurysms to prevent rebleeding might be considered in selected cases. [Neural Res 1997; 19: 385-388]     

Intracranial operation within seven days of aneurysmal subarachnoid hemorrhage. Results in 150 patients

We evaluated the results of intracranial operation in 150 consecutive patients surgically treated within seven calendar days of aneurysmal subarachnoid hemorrhage (SAH). Patients in all clinical grades, except those who were moribund, were treated. Those with either anterior or posterior circulation aneurysms were included. On follow-up assessment, favorable outcomes were noted in 107 patients (71%), 17 had major disabilities (11%), and 26 had died (17%). During hospitalization, vasospasm was diagnosed in 63 patients (42%) and rebleeding occurred in 39 (25%). Operations were performed throughout the first week after SAH; results of operation were similar on each day. A lower rate of good recovery was observed among patients operatively treated four to seven days after SAH than among those operated on earlier. The admitting neurologic condition influenced outcome after early operation, but age did not have a major impact. We find that aneurysm surgery can be performed within one week of SAH with acceptable results, although there is room for improvement.     

Pediatric intracranial aneurysms: current national trends in patient management and treatment

Purpose

Pediatric intracranial aneurysms constitute a medical disease process with many unique features that present unique challenges in orchestrating their treatment. Conflicts exist in pediatric aneurysm literature as to whether endovascular therapy is equivalent to surgical therapy in assuring durable aneurysm obliteration in this population.

Materials and methods

The national Healthcare Cost and Utilization Project (HCUP) Kid’s Inpatient Dataset was queried using the HCUPnet system. Overall trends in length of stay (LOS), associated charges, and in-hospital deaths were analyzed for both subarachnoid hemorrhage (SAH) and nonruptured aneurysms from 2000 to 2009. Trends in the type of procedure, associated LOS, and charges were analyzed for SAH from 2003 to 2009. A p value <0.05 was considered statistically significant.

Results

Mean LOS for SAH patients was an additional 7–10 days compared to patients discharged with nonruptured aneurysms. Costs of surgery showed a slight increase, while endovascular procedures also rose 50 % from 2006 to 2009. Interestingly, mean length of stay increased for endovascular procedures from 16.5 to 17.2 days and decreased for surgical procedures from 20.4 to 14.7 days (p?<?0.001).

Conclusions

First, in-hospital mortality and hospital length of stay for pediatric subarachnoid hemorrhage have not significantly declined since 1997. Second, in-hospital charges for the management of both ruptured and nonruptured aneurysms rose by over 200 % from 2000 to 2009. Surgical procedures saw a 6 % increase in price, while endovascular procedures sharply rose in costs by 50 %. Finally, endovascular therapy has increased in utilization, while the frequency of surgical therapy has not changed significantly since 2003.     

Aneurysmal SAH: cognitive outcome and structural damage after clipping or coiling.

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 prospectively 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 infarcts within the vascular territory of the aneurysm, but both groups had similar incidence of large infarcts 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.