Outcomes of Bypass Surgery in Adult Moyamoya Disease by Onset Type.

Importance: Moyamoya disease (MMD) is a rare chronic cerebrovascular disease, and the outcomes of bypass management in adult patients remain controversial. Objective: To categorize adult MMD based on asymptomatic, ischemic, and hemorrhagic onset and compare the outcomes (death, hemorrhagic stroke [HS], and ischemic stroke [IS]) of bypass surgery (direct or indirect) with those of conservative management. Design, Setting, and Participants: This retrospective, nationwide, population-based longitudinal cohort study used Korean National Health Insurance Research data to identify adults (aged ≥15 years) with MMD who were diagnosed between January 1, 2008, and December 31, 2020, and followed up until December 31, 2021 (median follow-up, 5.74 [IQR, 2.95-9.42] years). A total of 19 700 participants (3194 with hemorrhagic, 517 with ischemic, and 15 989 with asymptomatic MMD) were included. Data were analyzed from January 2 to April 1, 2023. Exposures: Bypass surgery and conservative management. Main Outcomes and Measures: Death constituted the primary outcome; secondary outcomes consisted of HS or IS. Kaplan-Meier survival curve and Cox proportional hazards regression analysis were applied. The propensity score-matching and stratified analyses were performed to control covariate effects. Results: A total of 19 700 patients (mean [SD] age, 45.43 [14.98] years; 12 766 [64.8%] female) were included. Compared with conservative management, bypass was associated with a reduced risk of death (adjusted hazard ratio [AHR], 0.50 [95% CI, 0.41-0.61]; P < .001) and HS (AHR, 0.36 [0.30-0.40]; P < .001) in hemorrhagic MMD; reduced risk of IS (AHR, 0.55 [95% CI, 0.37-0.81]; P = .002) in ischemic MMD; and reduced risk of death (AHR, 0.74 [95% CI, 0.66-0.84]; P < .001) in asymptomatic MMD. However, bypass was associated with an increased risk of HS (AHR, 1.76 [95% CI, 1.56-2.00]; P < .001) in asymptomatic MMD. Both direct and indirect bypass demonstrated similar effects in hemorrhagic and asymptomatic MMD, except only direct bypass was associated with a reduced risk of IS (AHR, 0.52 [95% CI, 0.33- 0.83]; P = .01) in ischemic MMD. After stratification, bypass was associated with a reduced risk of death in patients younger than 55 years with ischemic (AHR, 0.34 [95% CI, 0.13- 0.88]; P = .03) and asymptomatic (AHR, 0.69 [95% CI, 0.60-0.79]; P < .001) MMD, but an increased risk of HS in patients 55 years or older with ischemic MMD (AHR, 2.13 [95% CI, 1.1-4.16]; P = .03). Conclusions and Relevance: The findings of this cohort study of bypass outcomes for patients with MMD emphasize the importance of tailoring management strategies in adult patients based on onset types.

Association of Antiplatelet Therapy, Including Cilostazol, With Improved Survival in Patients With Moyamoya Disease in a Nationwide Study.

Background Although antiplatelet agents are frequently prescribed in moyamoya disease in routine clinical practice, there are no large-scale epidemiologic trials or randomized trial evidence to support their use in patients with moyamoya disease. Methods and Results Using the Korean National Health Insurance Service database, patients diagnosed with moyamoya disease between 2002 and 2016 were followed up for up to 14 years to assess, using time-dependent Cox regression in all patients and in a propensity score-matched cohort, the association of antiplatelet therapy and individual antiplatelet agents with survival. Among 25 978 patients with newly diagnosed moyamoya disease, mean age was 37.6±19.9 years, 61.6% were women, and total follow-up was 163 347 person-years. Among 9154 patients who were prescribed antiplatelet agents at least once during the follow-up period, the proportion prescribed cilostazol gradually increased from 5.5% in 2002 to 56.0% in 2016. Any antiplatelet use was associated with reduced risk of death (hazard ratio, 0.77; 95% CI, 0.70-0.84) in a multivariate model. Among individual antiplatelet agents, cilostazol was associated with greater reduction in mortality than the 5 other antiplatelet regimens. Subgroup analysis, according to the age group and history of ischemic stroke, and sensitivity analysis, using propensity score-matched analysis, revealed consistent results. Conclusions Antiplatelet therapy is associated with substantial improvement in survival in patients with moyamoya disease, and cilostazol is associated with greater survival benefit compared with other antiplatelet regimens. These results provisionally support the use of antiplatelet therapy in patients with moyamoya disease and the conduct of confirmatory randomized controlled trials.

Combined STA-MCA Bypass and Encephalodurosynangiosis Versus Encephalodurosynangiosis Alone in Adult Hemorrhagic Moyamoya Disease: A 5 -Year Outcome Study.

AIM: The purpose of this study was to compare the 5-year prognosis of combined superficial temporal artery- middle cerebral artery (STA-MCA) bypass and Encephalodurosynangiosis (EDAS) and EDAS alone in hemorrhagic moyamoya disease (MMD). METHODS: This study included 123 adult patients admitted to Beijing Tiantan Hospital with hemorrhagic MMD between 2010 and 2015. The surgical procedures included combined revascularization of STA-MCA anastomosis with EDAS (n = 79) or EDAS alone (n = 44). We recorded basic demographic data as well as several risks factors, and used multivariate regression analysis to evaluate the predictive factor of overall survival and rebleeding-free survival. RESULTS: Of the 123 patients with hemorrhagic MMD, the mean age was 37.97 ± 11.04 years old and the mean follow-up period was 65.9 months (ranging from 12 to 100 months). A total of 21 rebleeding events occurred in 19 patients, yielding an annual incidence of rebleeding of 3.1%. Of the 19 patients with rebleeding, 11 (57.8%) patients died of rebleeding and one patient experience 3 rebleeding events. In the combined revascularization group, 9 (11.3%) patients experienced rebleeding, of which 5 (6.3%) died. This incidence was lower than in the indirect group, where 22.7% of patients experienced rebleeding events and 13.6% died. However, no significant difference was found between these 2 groups. In Kaplan-Meier survival analysis, the combined revascularization group had a better prognosis than the EDAS alone group, and multivariate regression analysis revealed that the combined revascularization procedure was associated with a better outcome. CONCLUSIONS: Both combined revascularization and EDAS alone can reduce the risk of rebleeding in hemorrhagic MMD. Combined revascularization was found to be superior to EDAS alone in terms of preventing rebleeding events.

Late (5-20 years) outcomes after STA-MCA anastomosis and encephalo-duro-myo-arterio-pericranial synangiosis in patients with moyamoya disease.

OBJECTIVE: Surgical revascularization is known to reduce the incidence of further ischemic and hemorrhagic events in patients with moyamoya disease, but the majority of previous studies report only short-term (< 5 years) outcomes. Therefore, in this study the authors aimed to evaluate late (5-20 years) outcomes of moyamoya patients after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect bypass (encephalo-duro-myo-arterio-pericranial synangiosis [EDMAPS]). METHODS: Cumulative incidences of late morbidity/mortality and disease progression were evaluated among 93 patients who underwent STA-MCA anastomosis and EDMAPS. All of the patients were prospectively followed up for longer than 5 years postsurgery (10.5 ± 4.4 years). There were 35 pediatric and 58 adult patients. Initial presentation included transient ischemic attack/ischemic stroke in 80 patients and hemorrhagic stroke in 10 patients, and 3 patients were asymptomatic. Surgery was performed in a total of 141 hemispheres. Follow-up MRI/MRA was performed within a 6- or 12-month interval during the follow-up periods. RESULTS: During the follow-up periods, 92/93 patients were free from any stroke or death, but 1 patient had a recurrence of hemorrhagic stroke (0.10% per patient-year). Disease progression occurred in the territory of the contralateral carotid or posterior cerebral artery (PCA) in 19 hemispheres of 15 patients (1.5% per patient-year). The interval between initial surgery and disease progression varied widely, from 0.5 to 15 years. Repeat bypass surgery for the anterior and posterior circulation resolved ischemic attacks in all 10 patients. CONCLUSIONS: The study results indicate that STA-MCA anastomosis and EDMAPS would be the best choice to prevent further ischemic and hemorrhagic stroke for longer than 10 years on the basis of the demonstrated widespread improvement in cerebral hemodynamics in both the MCA and ACA territories in the study patients. However, after 10 years postsurgery regular follow-up is essential to detect disease progression in the territory of the contralateral carotid artery and PCA and prevent late cerebrovascular events.

Long-Term Outcomes of Indirect Bypass for 629 Children With Moyamoya Disease: Longitudinal and Cross-Sectional Analysis.

Background and Purpose- In pediatric moyamoya disease, there are few reports on the efficacy of surgical intervention for stroke prevention. We evaluated the long-term outcomes of indirect bypass surgery on a relatively large number of children with moyamoya disease in a single center. Methods- From August 1988 to December 2012, 772 children underwent indirect bypass surgery. This study included 629 patients who were followed up for >5 years, excluding patients with moyamoya syndrome. The mean clinical follow-up duration was 12 years (range, 5-29 years). Cross-sectional analysis was performed based on either Karnofsky Performance Scale or Lansky Play Performance Scale to evaluate overall clinical outcomes and factors associated with unfavorable outcomes. To analyze the longitudinal effect of surgery, the annual risk of symptomatic infarction or hemorrhage on the operated hemisphere after indirect bypass surgery was calculated with a person-year method, and the event-free survival rate was evaluated using the Kaplan-Meier method. Results- The overall clinical outcome was favorable in 95% of the patients. The annual risks of symptomatic infarction and hemorrhage on the operated hemispheres were 0.08% and 0.04%, respectively. Furthermore, the 10-year event-free survival rates for symptomatic infarction and hemorrhage were 99.2% and 99.8%. Conclusions- Indirect bypass surgery could provide satisfactory long-term improvement in overall clinical outcome and prevention of recurrent stroke in children with moyamoya disease.

Cerebrovascular events after surgery versus conservative therapy for moyamoya disease: a meta-analysis.

The background of this article is to determine the effect of a neurosurgical intervention in patients with moyamoya disease (MMD) on the risk of cerebrovascular events. We included studies with at least ten MMD patients in either intervention or control group which investigated cerebrovascular events during a minimal follow-up period of 1 year after neurosurgical intervention vs. conservative therapy. The primary outcome was all strokes; secondary outcome events were mortality, hemorrhagic, and ischemic stroke. Effects were evaluated for three prespecified subpopulations: adult, ischemic, and hemorrhagic moyamoya patients. We performed random-effects meta-analyses on odds ratios (ORs). We included 2,484 patients from 10 studies. The rate of all stroke was 14.1% in surgical treated compared to 30.0% in non-surgical-treated patients [pooled OR 0.38, 95%; confidence interval (CI) 0.23-0.64]. In subgroup analyses, we identified an association between surgery and all stroke in patients presenting with hemorrhagic, but not in patients with ischemic MMD. Hemorrhagic stroke during follow-up was less frequent in patients who underwent a surgical intervention, 4.6% compared to 18.6% of the conservatively treated patients (pooled OR 0.27, 95% CI 0.14-0.53). In addition, we observed a difference in mortality, 0.6% vs. 2.9% (pooled OR 0.32, 95% CI 0.13-0.77), but did not identify an association between surgical treatment and ischemic stroke (pooled OR 0.71, 95% CI 0.46-1.09). Surgical intervention in MMD is associated with a decreased risk of stroke most striking in patients presenting with hemorrhagic MMD. The relationship was present between surgical treatment and the outcome of hemorrhagic, but not ischemic stroke.

Natural Course of Moyamoya Disease in Patients With Prior Hemorrhagic Stroke.

Background and Purpose- Evidence on the natural history of hemorrhagic moyamoya disease is still insufficient. We investigated the incidence of recurrent intracranial bleeding, mortality, and risk factors for rebleeding in patients with moyamoya disease. Methods- A total of 128 conservatively managed patients with hemorrhagic presentation and complete follow-up data were included. Recurrent hemorrhages during long-term follow-up were documented. Annual and cumulative incidence rate of bleeding was generated via Kaplan-Meier survival analysis, and risk factors were analyzed using logistic regression analysis. Results- The median follow-up time was 10.1 (1-27) years. During a total of 1300.7 patient-years, 47 (36.7%) patients experienced 59 occurrences of recurrent hemorrhages, rendering an average annual incidence of 4.5%. Among them, 9 patients (19.1%) died from rebleeding and 12 patients sustained severe disability (modified Rankin Scale score of ≥3). The cumulative risk of rebleeding was 7.8% at 5 years, 22.6% at 10 years, and 35.9% at 15 years. Only 4 (3.1%) patients experienced ischemic stroke, yielding an average annual incidence of 0.3%. Multivariate analysis showed that smoking (odds ratio, 4.85; P=0.04) was an independent risk factor of rebleeding. Rebleeding (hazard ratio, 11.04; P=0.02) and hypertension (hazard ratio, 4.16; P=0.04) were associated with increased mortality. Age, type of initial bleeding, digital subtraction angiography staging, family history, and coexisting cerebral aneurysms were not associated with increased risk of rebleeding. Conclusions- Rebleeding events were common and the main cause of death in patients with hemorrhagic moyamoya disease. The risk of rebleeding steadily increased during long-term follow-up. Smoking was a risk factor for rebleeding, and hypertension was associated with increased mortality.

Encephaloduroarteriosynangiosis for pediatric moyamoya disease: long-term follow-up of 100 cases at a single center.

OBJECTIVE The object of this study was to summarize the long-term effect of encephaloduroarteriosynangiosis (EDAS) for the treatment of pediatric moyamoya disease (MMD) and to investigate factors influencing the clinical outcomes of EDAS. METHODS Clinical features, angiographic findings, and clinical outcomes were analyzed among MMD patients younger than 18 years who had been treated with EDAS between 2002 and 2007 at the authors' institution. The Kaplan-Meier method was used to estimate stroke risk after EDAS. Predictors of neurological outcome were assessed. RESULTS One hundred fifteen patients were identified. The mean age at symptom onset was 7.3 ± 4.0 years. The incidence of familial MMD was 11.3%. The female/male ratio was 1:1.16. A total of 232 EDAS procedures were performed, and the incidence of postoperative complications was 3%. Postoperative digital subtraction angiography was performed in 54% of the patients, and about 80% of the hemispheres showed good or excellent results. Neovascularization showed significant correlations with delay time (from symptom onset to first operation), Suzuki stage, and preoperative stroke (all p < 0.05). Clinical follow-up was available in 100 patients with a mean follow-up of 124.4 ± 10.5 months. Ten-year cumulative survival was 96.5% after surgery, and the risk of stroke was 0.33%/person-year. An independent life with no significant disability was reported by 92% of the patients. A good outcome correlated with a low Suzuki stage (p = 0.001). Older children and those without preoperative stroke had better clinical outcomes (p < 0.05). CONCLUSIONS On the basis of long-term follow-up data, the authors concluded that EDAS is a safe and effective treatment for pediatric MMD, can reduce the risk of subsequent neurological events, and can improve quality of life. The risk of ischemia-related complications was higher in younger patients, and older children showed better outcomes. Compensation was greater with more prominent cerebral ischemia. The long-term clinical outcome largely depended on the presence and extent of preoperative stroke.

Epidemiological Features of Nontraumatic Spontaneous Subarachnoid Hemorrhage in China: A Nationwide Hospital-based Multicenter Study.

BACKGROUND: Nontraumatic spontaneous subarachnoid hemorrhage (SAH) is associated with a high mortality. This study was conducted to investigate the epidemiological features of nontraumatic spontaneous SAH in China. METHODS: From January 2006 to December 2008, the clinical data of patients with nontraumatic SAH from 32 major neurosurgical centers of China were evaluated. Emergent digital subtraction angiography (DSA) was performed for the diagnosis of SAH sources in the acute stage of SAH (≤3 days). The results and complications of emergent DSA were analyzed. Repeated DSA or computed tomography angiography (CTA) was suggested 2 weeks later if initial angiographic result was negative. RESULTS: A total of 2562 patients were enrolled, including 81.4% of aneurysmal SAH and 18.6% of nonaneurysmal SAH. The total complication rate of emergent DSA was 3.9% without any mortality. Among the patients with aneurysmal SAH, 321 cases (15.4%) had multiple aneurysms, and a total of 2435 aneurysms were detected. The aneurysms mostly originated from the anterior communicating artery (30.1%), posterior communicating artery (28.7%), and middle cerebral artery (15.9%). Among the nonaneurysmal SAH cases, 76.5% (n = 365) had negative initial DSA, including 62 cases with peri-mesencephalic nonaneurysmal SAH (PNSAH). Repeated DSA or CTA was performed in 252 patients with negative initial DSA, including 45 PNSAH cases. Among them, the repeated angiographic results remained negative in 45 PNSAH cases, but 28 (13.5%) intracranial aneurysms were detected in the remaining 207 cases. In addition, brain arteriovenous malformation (AVM, 7.5%), Moyamoya disease (7.3%), stenosis or sclerosis of the cerebral artery (2.7%), and dural arteriovenous fistula or carotid cavernous fistula (2.3%) were the major causes of nonaneurysmal SAH. CONCLUSIONS: DSA can be performed safely for pathological diagnosis in the acute stage of SAH. Ruptured intracranial aneurysms, AVM, and Moyamoya disease are the major causes of SAH detected by emergent DSA in China.

Incidence and long-term outcome of postradiotherapy moyamoya syndrome in pediatric patients with primary brain tumors: a single institute experience in Taiwan.

We aimed to investigate the incidence and long-term outcome of moyamoya syndrome in pediatric patients with primary brain tumors after receiving cranial radiotherapy (RT) in a single institute in Taiwan. The complete medical records, medical images, and RT notes of 391 pediatric patients with primary brain tumors treated with cranial RT between January 1975 and December 2005 in Taipei Veterans General Hospital (TVGH), Taiwan, were entered into an electronic registry and reviewed. Eight (2%) cases of post-RT moyamoya syndrome were identified in the sample of 391 patients. The median latency was 3 years post-RT. Among the eight patients, three had craniopharyngioma, two had optic glioma, two had medulloblastoma, and one had a suprasellar astrocytoma. The prescribed physical doses of RT were in the range of 40-54 Gy. The incidence was highest in those with optic glioma (0.039/person-year), followed by craniopharyngioma (0.013/person-year), astrocytoma (0.003/person-year), and medulloblastoma (0.002/person-year). No patients died of vasculopathy. No difference in crude incidence was found between our results and those of other series. The incidence of moyamoya syndrome was diagnosis dependent, with the highest incidence among patients with optic glioma. No regional difference in incidence was found. Long-term, stable neurological function may be achieved following timely surgical intervention.

Indications and results of direct cerebral revascularization in the modern era.

BACKGROUND: There has been a progressive decrease in the indications for cerebral revascularization during the past 30 years, particularly with the advance of endovascular techniques. Our objective was to define indications for and evaluate outcomes of patients treated with bypass surgery in the modern endovascular era. METHODS: We retrospectively reviewed the charts of all patients who underwent direct cerebral revascularization procedures between January 2006 and March 2013. RESULTS: In total, 121 patients underwent 131 direct microsurgical revascularization procedures. The indications for bypass surgery were moyamoya angiopathy (40 patients, 47 bypasses), complex aneurysms (54 patients, 56 bypasses), and occlusive vascular disease (27 patients, 28 bypasses). Revascularization resulted in improvement of symptoms in 77.5% of patients with moyamoya angiopathy (mean clinical follow-up 18.8 months) and 55.5% of patients with occlusive vascular disease (mean clinical follow-up 10.4 months). Among the aneurysm patients treated with revascularization, 81.5% had a favorable outcome (Glasgow Outcome Scale score 4-5) at long-term follow-up (mean clinical followup 18.5 months). CONCLUSIONS: Although microvascular cerebral revascularization is no longer performed as commonly as in the past, it remains an essential part of the skill set required to treat select vascular pathologies. Complex aneurysms are the single largest indication for direct bypass procedures. Moyamoya disease is by far the largest indication if indirect bypass procedures are included in the analysis. In experienced hands, the morbidity and mortality of patients undergoing cerebral revascularization procedures are low and long-term outcomes generally excellent.

Outcome in adult patients with hemorrhagic moyamoya disease after combined extracranial-intracranial bypass.

OBJECT: The outcome of patients with hemorrhagic moyamoya disease (MMD) after cerebral revascularization is uncertain. The purpose of this study was to delineate the efficacy of this surgical method in the treatment of hemorrhagic MMD. METHODS: Between January 2007 and August 2011, a consecutive cohort of 113 patients with hemorrhagic MMD was enrolled into this prospective single-center cohort study. The surgical method was combined direct and indirect bypass. The cumulative probability of the primary end point (all stroke and deaths from surgery through 30 days after surgery and ipsilateral recurrent hemorrhage afterward) was analyzed. The angiographic outcome was measured by the following parameters: bypass patency, reduction of basal MMD vessels, improved degree of dilation, and branch extension of the anterior choroidal and posterior communicating arteries (AChA-PCoA). RESULTS: Of the 113 enrolled cases, CT scans revealed pure intraventricular hemorrhage (IVH) in 63 cases (55.7%), pure intracranial hemorrhage (ICH) in 14 cases (12.4%), and ICH with IVH in 36 cases (31.9%). In 74 of 113 hemorrhagic hemispheres (65.5%), the AChA-PCoA was extremely dilated with extensive branches beyond the choroidal fissure. A total of 114 surgeries were performed. No patient suffered ischemic or hemorrhagic stroke through 30 days after surgery. Ipsilateral rebleeding occurred in 5 patients, 4 of whom died of the rebleeding event. The cumulative probability of the primary end point was 0% at 1 year and 1.9% at 2 years. The annual rebleeding rate was 1.87%/person/year. The improvement in AChA-PCoA extension was observed in 75 of 107 operated hemispheres (70.1%), which was higher than that in 7 of 105 unoperated hemispheres (35.2%). CONCLUSIONS: Revascularization may provide a benefit over conservative therapy for hemorrhagic MMD patients. The improvement of dilation and branch extension of AChA-PCoA might be correlated with the low rebleeding rate.

Long-term outcomes in adult patients with ischemic-type moyamoya disease involving posterior circulation.

BACKGROUND: The object of this study was to compare the long-term outcomes in adult patients with moyamoya disease (MMD) with posterior circulation involvement (PCi) treated through surgical revascularization with those in adult patients without PCi. METHODS: The records of 32 consecutive adult patients with ischemic-type MMD who were treated with revascularization were reviewed. Twelve of these patients (38 %) had PCi at initial onset. Clinical characteristics of the patients with PCi were compared to those without PCi. Neurological outcomes were assessed using the modified Rankin Scale (mRS) in the preoperative and postoperative follow-up periods. A five-year Kaplan-Meier stroke risk was calculated. RESULTS: The frequency of presenting with infarction was significantly higher among patients with PCi than among those without PCi (p = 0.006). mRS scores in the preoperative period were significantly higher in patients with PCi than in patients without PCi (p = 0.0004). There were no significant differences in mRS scores between the preoperative and postoperative follow-up period in patients with PCi (p = 0.3), nor were there any between the preoperative and postoperative follow-up periods in patients without PCi (p = 0.2). The five-year Kaplan-Meier risk of surgical morbidity and ipsilateral stroke was 14.3 % in surgically treated hemispheres with PCi versus 14.9 % in surgically treated hemispheres without PCi (p = 0.96). CONCLUSIONS: PCi at initial onset was significantly correlated with poor outcome. Revascularization for the middle cerebral artery territory in patients with PCi was effective at preventing recurrent ischemic stroke.

The natural history of moyamoya in a North American adult cohort.

Moyamoya disease and moyamoya syndrome (MMD/S) are a considerable source of neurologic morbidity in adults as a result of both ischemic and hemorrhagic events. Unfortunately, there is a paucity of literature detailing the natural course of MMD/S in the USA. To elucidate epidemiological information, stroke rates, hemorrhage rates, and risk factors for these events in patients with MMD/S, we reviewed our own institutional cohort of 42 North American adults with MMD/S. The mean patient age was 38.8 (standard deviation [SD] 12.7) with a 5:1 female-to-male predominance. About 74% of patients had an ischemic presentation while only 17% presented with hemorrhage. The mean Suzuki grade was higher in patients presenting with hemorrhage (3.7 compared to 2.9, p=0.03) but similar in those who presented with a stroke as compared to those who did not (3.00 compared to 3.05, p=0.88). The overall annual stroke and hemorrhage rates were 13.3% and 1.7%, respectively. Statistically significant risk factors for stroke or hemorrhage were female sex (p=0.031) and stroke presentation within 3 years (hazard ratio [HR]=4.08, p=0.035). Smoking was another risk factor, but it did not meet statistical significance (HR=1.56, p=0.38). We conclude that these results favor intervention for MMD/S to mitigate the high annual stroke risk. This particularly applies to females and/or those presenting with a recent stroke/hemorrhage. Our results also serve as a baseline for comparison of hemorrhage rates after intervention.

Surgical treatment of moyamoya disease in adults: combined direct and indirect vs. indirect bypass surgery.

Combined superficial temporal artery-middle cerebral artery anastomosis and encephalo-duro-arterio-galeo-synangiosis (EDAGS) were retrospectively compared with indirect bypass, EDAGS with or without inversion, in 134 hemispheres of 96 adult patients with non-hemorrhagic moyamoya disease (MMD) in terms of angiographic findings, perioperative complications, and clinical outcome. Angiographic revascularization seemed to be better in the combined bypass group compared with the EDAGS group (p = 0.045), but perioperative complication tended to be slightly more common in the combined bypass group. No statistical differences were found in clinical outcome. EDAGS is a very reliable alternative to combined bypass in adult MMD. However, randomized clinical trials are needed to assess the long-term efficacy of any bypass surgery in adult patients with MMD.

Sex differences in clinical presentation and treatment outcomes in Moyamoya disease.

BACKGROUND: Moyamoya (MM) disease is an idiopathic steno-occlusive angiopathy occurring more frequently in females. OBJECTIVE: To evaluate sex differences in preoperative symptoms and treatment outcomes after revascularization surgery. METHODS: We analyzed 430 MM disease patients undergoing 717 revascularization procedures spanning 19 years (1991-2010) and compared gender differences in preoperative symptoms and long-term outcomes after surgical revascularization. RESULTS: A total of 307 female and 123 male patients (ratio, 2.5:1) with a mean age of 31.0 ± 16.7 years and adults-to-children ratio of 2.5:1 underwent 717 revascularization procedures. Female patients were more likely to experience preoperative transient ischemic attacks (odds ratio: 2.1, P = .001) and less likely to receive a diagnosis of unilateral MM disease (odds ratio: 0.6, P = .04). No association was observed between sex and risk of preoperative ischemic or hemorrhagic stroke. There was no difference in neurological outcome because both male and female patients experienced significant improvement in the modified Rankin Scale score after surgery (P < .0001). On Kaplan-Meier survival analysis, 5-year cumulative risk of adverse postoperative events despite successful revascularization was 11.4% in female vs 5.3% in male patients (P = .05). In multivariate Cox proportional hazards analysis, female sex trended toward an association with adverse postoperative events (hazard ratio: 1.9, P = .14). CONCLUSION: Female patients are more susceptible to the development of preoperative transient ischemic attack and may be at higher risk of adverse postoperative events despite successful revascularization. There is, however, no sex difference in neurological outcome because patients of both sexes experience significant improvement in neurological status with low risk of the development of future ischemic events after surgical revascularization.

Moyamoya disorder in the United States.

BACKGROUND: In Asian populations, moyamoya disease has a well-defined phenotype including a bimodal age of presentation with children typically presenting with ischemic phenomena and adults presenting with hemorrhage. Studies have provided evidence that moyamoya disease in the United States may exhibit a different phenotype. OBJECTIVE: To assess overall rates of admission, demographics, procedures, and outcomes of patients admitted or diagnosed with moyamoya disorder in US hospitals. METHODS: A comprehensive assessment of the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project (2002-2008) was performed. Patient demographics, comorbidities, procedures, and outcomes were analyzed. RESULTS: There were 2280 admissions for moyamoya disorder with a predicted national estimate of 11 163 admissions (0.57/100 000 persons/y). Over time, there was a significant increase in diagnosis and associated ischemic strokes. Females (72%) were affected more than males (28%). Demographics included white (49%), black (24%), Hispanic (11%), Asian (11%), and other (3.3%). Mean age at presentation was 31.6 ± 18.0. Children were significantly more likely to be diagnosed with ischemic phenomena (16.4%) than hemorrhage (3.3%), as were adults (18.8% vs 11.0%). Status at discharge was largely routine (74.8%) vs short-term hospital (3%), home health care (7%), transfer to another hospital (12%), or in-hospital death in 2.3%. CONCLUSION: Patients admitted to US hospitals diagnosed with moyamoya disorder were more commonly female and white, and both adults and children were more likely to be diagnosed with ischemic vs hemorrhagic stroke. Over time, there was an increase in diagnosis, associated ischemic stroke, and treatment with extracranial-intracranial bypass.

Regional differences in incidence and patient characteristics of moyamoya disease: a systematic review.

BACKGROUND AND PURPOSE: Moyamoya disease (MMD) is a rare cause of stroke, initially described in Japan. In other countries, incidences and presenting symptoms may differ from those in Japan. The literature on regional differences in incidence and patient characteristics of MMD was systematically reviewed. METHODS: Medline, EMBASE and CINAHL were searched for population based studies on MMD published between January 1969 and January 2011. From studies that met predefined inclusion criteria, information was extracted on incidence and patient characteristics. Incidences with corresponding 95% CIs if possible were calculated and descriptive statistics for patient characteristics were used. RESULTS: 8 studies were included: three from Japan, one each from Taiwan and China and three from the USA. Incidences per 100 000 patient years ranged in Japan from 0.35 to 0.94 (95% CI 0.69 to 1.19), in the USA from 0.05 (-0.04 to 0.12) in Iowa to 0.17 (-0.06 to 0.40) in Hawaii and were 0.41 (0.28 to 0.54) in Nanjing, China and 0.02 (0.003 to 0.04) in Taiwan. Female to male ratio ranged from 1.1 (0.9 to 1.5) in Nanjing to 2.8 (1.2 to 6.1) in Iowa. Proportions with intracerebral haemorrhage as the initial presentation were 56% in China, 52% in Taiwan, 29% in Hawaii, 21% in Japan and 10% in Iowa. Patients with childhood onset presented most often with ischaemia (>75%) in all regions. CONCLUSIONS: MMD incidence was higher in Japan and China than in Taiwan and North America and presenting symptoms showed regional differences, which are thus far unexplained. Population based data on MMD in Europe are lacking.

Moyamoya disease: review of the literature and estimation of excess morbidity and mortality.

As a result of greater screening with brain imaging tests, the incidence of Moyamoya Disease (MMD) is increasing. In the past, comparative mortality experience has been based on small patient numbers and relatively short follow-up periods. The objective of this article is to estimate the degree of excess morbidity and mortality associated with this rare impairment. In addition we will provide a concise review of the literature, including pathophysiology, clinical manifestation, diagnostic criteria and surgical treatment.

Primary intraventricular hemorrhage: yield of diagnostic angiography and clinical outcome.

INTRODUCTION: Primary intraventricular hemorrhage (IVH), bleeding in the ventricular system without a discernable parenchymal component, is a rare neurological disorder. To better define the features of primary IVH and the yield of diagnostic angiography in this condition, we retrospectively analyzed all cases of primary IVH evaluated at a tertiary referral hospital over a 6-year period and performed a systematic review of the literature. METHODS: For the retrospective case series, all patients with primary IVH admitted to the neurovascular service at a single tertiary referral center over a 6-year period were identified by screening a departmental database. For the systematic review of the literature, all case series of patients with primary IVH diagnosed by computed tomography were identified in the Medline database. RESULTS: From the systematic review, the majority of patients with spontaneous primary IVH presented with headache (69%), nausea/vomiting (53%), and altered mental status (66%). Most primary IVH patients had associated hydrocephalus (62%), and about one-third required ventricular drainage (34%). Diagnostic cerebral angiography was positive for a bleeding source in 56%. The two most common causes identified by angiography were arteriovenous malformations (58% of positive angiograms) and aneurysms (36% of positive angiograms). Approximately one-third of patients with primary IVH do not survive hospital discharge (39%). Patient age and amount of IVH independently predicted in-hospital mortality. CONCLUSIONS: Primary IVH is a rare form of intracerebral hemorrhage, with varying short-term outcomes that depend on patient age and the extent of intraventricular hemorrhage. The yield of diagnostic cerebral angiography in the setting of primary IVH is very high. The two most common causes of primary IVH identified on angiography are arteriovenous malformations and aneurysms. Routine catheter angiography in the setting of primary IVH is warranted.