Characteristics of Moyamoya Disease Based on National Registry Data in Japan

Impact of Cerebral Revascularization on Pial Collateral Flow in Patients With Unilateral Moyamoya Disease Using Quantitative Magnetic Resonance Angiography

BACKGROUND AND OBJECTIVES

Moyamoya disease (MMD) is a chronic steno-occlusive disease of the intracranial circulation that depends on neoangiogenesis of collateral vessels to maintain cerebral perfusion and is primarily managed with cerebral revascularization surgery. A quantitative assessment of preoperative and postoperative collateral flow using quantitative magnetic resonance angiography with noninvasive optimal vessel analysis (NOVA) was used to illustrate the impact of revascularization on cerebral flow distribution.

METHODS

A retrospective review of patients with unilateral MMD who underwent direct, indirect, or combined direct/indirect cerebral revascularization surgery was conducted between 2011 and 2020. Using NOVA, flow was measured at the anterior cerebral artery (ACA), ACA distal to the anterior communicating artery (A2), middle cerebral artery (MCA), posterior cerebral artery (PCA), and PCA distal to the posterior communicating artery (P2). Pial flow (A2 + P2) and collateral flow (ipsilateral [A2 + P2])-(contralateral [A2 + P2]) were measured and compared before and after revascularization surgery. Total hemispheric flow (MCA + A2 + P2) with the addition of the bypass graft flow postoperatively was likewise measured.

RESULTS

Thirty-four patients with unilateral MMD underwent cerebral revascularization. Median collateral flow significantly decreased from 68 to 39.5 mL/min ( P = .007) after bypass. Hemispheres with maintained measurable bypass signal on postoperative NOVA demonstrated significant reduction in median collateral flow after bypass ( P = .002). Median total hemispheric flow significantly increased from 227 mL/min to 247 mL/min ( P = .007) after bypass. Only one patient suffered an ipsilateral ischemic stroke, and no patients suffered a hemorrhage during follow-up.

CONCLUSION

NOVA measurements demonstrate a reduction in pial collateral flow and an increase in total hemispheric flow after bypass for MMD, likely representing a decrease in leptomeningeal collateral stress on the distal ACA and PCA territories. Further studies with these measures in larger cohorts may elucidate a role for NOVA in predicting the risk of ischemic and hemorrhagic events in MMD.

Stroke Events and Risk Factors in Older Patients with Moyamoya Disease

BACKGROUND

We aimed to comprehensively analyze the epidemiology, natural history, stroke events and their risk factors, and the RNF213 p.Arg4810Lys variant in older patients with moyamoya disease (MMD).

METHODS

We enrolled patients with MMD followed-up at our hospital between 2000 and 2023. Those who developed MMD at age ≥60 years or were diagnosed at a younger age and followed-up after age 60 years were included. Baseline characteristics, onset type, radiologic features, and RNF213 p.Arg4810Lys variant status were investigated.

RESULTS

Among 56 patients with 100 affected hemispheres, 62 were asymptomatic, 26 experienced ischemic onset, and 12 had hemorrhagic onset. A higher incidence of anterior choroidal artery (AchA) dilatation and lower proportion of favorable modified Rankin scale scores were detected in hemorrhagic onset, whereas greater prevalence of bypass surgery in ischemic onset. Of 76 asymptomatic hemispheres at the age of 60 years, subsequent stroke events occurred in 10 hemispheres, comprising 8 hemorrhages and 2 ischemias. Risk factors for de novo hemorrhage in asymptomatic hemispheres included AchA dilatation and choroidal anastomosis. Comparison of the RNF213 p.Arg4810Lys variant status showed no significant differences in baseline characteristics, onset types, or imaging findings, except for a higher percentage of patients in the GA group with a family history of MMD.

CONCLUSIONS

Hemorrhagic events were the most prevalent and prognostically deteriorating factors in older patients with MMD aged ≥60 years. AchA dilatation and choroidal anastomosis were predictors of de novo hemorrhage in asymptomatic nonsurgical hemispheres in older patients with MMD.

Neuropsychological Test Performance Differentiates Subgroups of Individuals With Adult Moyamoya Disease: A Cross-Sectional Clinical Study

BACKGROUND AND OBJECTIVES

Moyamoya disease (MMD) is a rare noninflammatory disorder involving progressive intracranial vasculopathy and impaired cerebral blood flow in the anterior circulation, resulting in stroke and cognitive impairment. We aimed to characterize cognitive impairment and the possible predictive value of sociodemographic and clinical characteristics of adults with MMD.

METHODS

This cross-sectional study examined neurocognitive performance in a group of 42 consecutive adult patients (mean age = 40.52 years; 69% female) referred for a presurgical neuropsychological evaluation. Neuropsychological functioning was assessed with a comprehensive battery, and cognitive dysfunction was defined as 1.5 SDs below the mean. Neurocognitive performance correlated with clinical/demographic characteristics and disease markers.

RESULTS

Most patients (91%) had a history of stroke, and 45% had cognitive deficits, most notably on measures of attention/speed (48%), executive functioning (47%), visuoconstruction (41%), and memory (31%-54%). Only higher educational attainment and poor collateral blood flow in the right hemisphere differentiated cognitively impaired (n = 19) and intact groups (n = 23), and MMD-related characteristics (eg, disease duration, stroke history) did not differentiate the 2 groups.

CONCLUSION

Consistent with previous work, frontal-subcortical cognitive deficits (eg, deficits in mental speed, attention, executive functioning) were found in nearly half of patients with MMD and better cognitive performance was associated with factors related to cognitive reserve. Angiographic metrics of disease burden (eg, Suzuki rating, collateral flow) and hemodynamic reserve were not consistently associated with poorer cognitive outcomes, suggesting that cognition is a crucial independent factor to assess in MMD and has relevance for treatment planning and functional status.

Moyamoya disease in Southeast Asians: genetic and autopsy data, new cases, systematic review, and meta-analysis of all patients from the literature

BACKGROUND

Moyamoya disease (MMD) is a rare disorder causing ischemic and hemorrhagic juvenile stroke. It is associated with the founder susceptibility variant p.R4810K in the RNF213 gene in East Asia. Our aim was to enhance understanding of MMD in so far poorly characterized Southeast Asians and exploring differences with Caucasian Europeans.

METHODS

By retrospective analysis of medical records and systematic database search on PubMed for all published cases, we identified Southeast Asian patients with MMD. We extracted and pooled proportions using fixed-effects models. Our own cohort was tested for the East Asian RNF213 founder variant p.R4810K. One of our Southeast Asian patients underwent post-mortem histopathological examination.

RESULTS

The study cohort comprised 32 Southeast Asians. Mean age at onset in the entire cohort was 32.5 ± 20.3 years (n = 24), 43.4 ± 8.7 years in patients admitted to our center (n = 11), and 23.4 ± 22.4 years in patients from the international literature (n = 13). Female-to-male ratio was 1.6:1. MMD predominantly affected bilateral anterior intracranial vessels. Cerebral ischemia outnumbered transient ischemic attacks (TIAs) and intracranial hemorrhage. TIAs, arterial hypertension and obesity were significantly less frequent in Southeast Asian patients compared to Caucasian Europeans. p.R4810K was absent in all examined Southeast Asians despite of typical histopathological signs of MMD in one autopsy case.

CONCLUSION

Clinical and histopathological manifestations of MMD in Southeast Asians are similar to those in Caucasian Europeans. The genotype of MMD in Southeast Asians differs from that of most East Asian patients.

Incidence, prevalence, and treatment of Moyamoya disease in Japan: A population-based descriptive study

BACKGROUND

Moyamoya disease (MMD) is characterized by progressive stenosis or occlusion of the terminal portions of the bilateral internal carotid arteries. A Japanese survey in 2003 reported an incidence and prevalence of MMD of 0.54 and 6.03 per 100,000 people, respectively, showing an upward trend over previous surveys. An update to these estimates is therefore warranted. Additionally, evidence is lacking on trends in revascularization and antiplatelet therapy in MMD patients.

METHODS

We conducted a population-based descriptive study using a Japanese claims database. From fiscal year (FY) 2015 to 2019, we standardized the incidence and prevalence estimates of MMD to the 2015 Japanese census population by age and sex. We also estimated the 1-year cumulative incidence of revascularization among incident MMD patients and the proportion of prevalent MMD patients receiving antiplatelet therapy in each FY.

RESULTS

The age-standardized male-to-female ratio of both incident and prevalent MMD patients was approximately 1:2. Standardized incidence and prevalence of MMD per 100,000 population increased slightly from 1.8 to 2.4 and 14.7 to 17.6, respectively. The 1-year cumulative incidence of revascularization among incident MMD patients varied between 21.9 % and 28.9 %. Among prevalent MMD patients, 36.6 % to 39.0 % received antiplatelet therapy.

CONCLUSIONS

The incidence and prevalence of MMD in Japan from FY 2015 to 2019 were higher than those estimated in 2003. The trends in revascularization and antiplatelet therapy identified in this study will be useful in further improving the quality of MMD clinical practice.

Neuropsychiatric Symptoms of Moyamoya Disease: Considerations for the Clinician

Neurocognitive impairment in moyamoya disease is common, under recognized, and potentially devastating. The purpose of this paper is to provide an updated overview on this topic for the practicing clinician. We searched PubMed for keywords including cognitive impairment, neurocognitive dysfunction, and neuropsychological recovery in moyamoya disease. We summarized the literature to provide a concise review of the treatment and management of neuropsychiatric symptoms associated with moyamoya disease. Neuropsychiatric sequelae have conventionally been attributed to chronic cerebral hypoperfusion and/or stroke. Cognitive dysfunction in adults with moyamoya disease is most commonly in the form of impaired executive function, whereas intelligence is the predominant impairment in children with moyamoya disease. Pharmacotherapy for treatment of the neuropsychiatric symptoms associated with moyamoya disease is appropriate and can improve quality of life; however, careful consideration is needed to avoid adverse cerebrovascular events. It remains unclear as to whether surgical revascularization improves or stabilizes cognitive performance and outcomes. Additional prospective studies are warranted to better understand the long-term impact of revascularization on cognitive functioning in moyamoya disease.

Predictive Factors for Seizures after Revascularization in Patients with Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a rare and complex cerebrovascular disorder that is diagnosed through imaging studies, such as computed tomography or magnetic resonance imagin, which show progressive narrowing of the terminal portion of the internal carotid arteries and the development of compensatory capillary collaterals. The objective of our study was to identify and clarify the predictive factors for seizures in patients with MMD.

METHODS

From January 2019 to March 2023, a total of 102 patients with MMD were enrolled in this study. Ten patients with seizures after surgery as the main presentation were included. Patients with epilepsy were compared to those without epilepsy in terms of their clinical characteristics. Multivariable analysis was applied to determine factors linked with postoperative seizures.

RESULTS

Ten patients developed seizures after revascularization for MMD. Logistic regression analysis revealed that early seizure (odds ratio [OR], 0.068; 95% CI, 0.014-0.342; P = 0.001), cortical involvement (OR, 9.593; 95% CI, 2.256-40.783; P = 0.002), and postoperative hyperperfusion (OR, 7.417; 95% CI, 1.077-51.093; P = 0.042) were significantly associated with seizures. In a multivariate analysis, it was found that early seizures were significantly associated with a higher likelihood of experiencing seizures (OR, 5.88; 95% CI, 1.01-33.96; P = 0.048), while patients who had seizures were more likely to have cortical involvement (OR, 8.90; 95% CI, 1.55-50.96; P = 0.014) or postoperative hyperperfusion (OR, 12.44; 95% CI, 1.21-127.74; P = 0.034).

CONCLUSIONS

Epilepsy in patients with MMD link with several clinical factors. In patients with MMD who undergo bypass surgery, early seizures, cortical involvement, and postoperative hyperperfusion are significant independent predictive factors for the development of epilepsy.

A Functional Magnetic Resonance Imaging Study Using Dynamic Amplitude of Low-Frequency Fluctuation to Assess Brain Activity in Patients with Moyamoya Disease

Introduction: The purpose of this study was to monitor and record the dynamic brain activity of patients with moyamoya disease (MMD), as well as to study the relationship between brain abnormalities and presenting clinical features. Methods: A total of 16 patients with MMD (2 males and 14 females) were invited to participate in the study, as were healthy controls (HCs) with the same number and sex ratio. In this study, the dynamic amplitude of low-frequency fluctuation (dALFF) was utilized to assess changes in spontaneous brain activity. Moreover, we also used correlation analysis to study the relationship among the measured mean of dALFF, behavioral performances, and the retinal nerve fiber layer and the Hospital Anxiety and Depression Scale (HADS) score to explore the potential relationship between MMD and anxiety and depression. Results: Our study reveals that in MMD, dALFF levels decreased in the left lingual gyrus, right insula, and occipital lobe. Discussion: In this study, we found and discussed the potential relationship between the abnormal activities in multiple brain regions and related functional network disorders in patients with MMD, as well as the damage to brain regions that process emotion and vision, in the hopes of providing more ideas for the clinical diagnosis and treatment of MMD.

Association of Bypass Surgery and Mortality in Moyamoya Disease

BACKGROUND

Patients with moyamoya disease (MMD) have a high risk of stroke or death. We investigated whether extracranial to intracranial bypass surgery can reduce mortality by preventing strokes in patients with MMD.

METHODS AND RESULTS

This nationwide retrospective cohort study encompassed patients with MMD registered under the Rare Intractable Diseases program via the Relieved Co-Payment Policy between 2006 and 2019, using the Korean National Health Insurance Service database. Following a 4-year washout period, landmark analyses were employed to assess mortality and stroke occurrence between the bypass surgery group and the nonsurgical control group at specific time points postindex date (1 month and 3, 6, 12, and 36 months). The study included 18 480 patients with MMD (mean age, 40.7 years; male to female ratio, 1:1.86) with a median follow-up of 5.6 years (interquartile range, 2.5-9.3; mean, 6.1 years [SD, 4.0 years]). During 111 775 person-years of follow-up, 265 patients in the bypass surgery group and 1144 patients in the nonsurgical control group died (incidence mortality rate of 618.1 events versus 1660.3 events, respectively, per 105 person-years). The overall adjusted hazard ratio (HR) revealed significantly lower all-cause mortality in the bypass surgery group from the 36-month landmark time point, for any stroke mortality from 3- and 6-month landmark time points, and for hemorrhagic stroke mortality from the 6-month landmark time point. Furthermore, the overall adjusted HRs for hemorrhagic stroke occurrence were beneficially maintained from all 5 landmark time points in the bypass surgery group.

CONCLUSIONS

Bypass surgery in patients with MMD was associated with a lower risk of all-cause and hemorrhagic stroke mortality and hemorrhagic stroke occurrence compared with nonsurgical control.

Bypass Surgery for Adult-Onset Hemorrhagic Moyamoya Disease: Analysis Classified by Site of Initial Bleeding

OBJECTIVE

Prevention of rebleeding events is crucial for patients with hemorrhagic moyamoya disease (MMD), as these increase the risk of mortality. Bypass surgery is effective in preventing subsequent hemorrhage, particularly in patients with posterior hemorrhage, but its efficacy in those with anterior hemorrhage remains unclear. We analyzed the effects of surgical intervention, stroke risk factors, and radiological features on rebleeding events.

METHODS

Patients with hemorrhagic-onset MMD who were followed at our institution between 2000 and 2022 were included (41 adult patients, 45 hemispheres). Baseline characteristics and radiological features (anterior or posterior hemorrhagic site, Suzuki grade, posterior cerebral artery involvement, and periventricular anastomosis) were thoroughly reviewed.

RESULTS

Of the 45 hemispheres, hemorrhage developed in 9 (20%) hemispheres, with a median duration until rebleeding of 38 (range: 1-44) months. Rebleeding rates were significantly lower in the surgical group than in the nonsurgical group (odds ratio: 0.09; 95% confidence interval [CI]: 0.01-0.79; P = 0.011), and Kaplan-Meier analysis revealed a significantly longer interval between bleeding events in the surgical group (1.3%/y vs. 5.3%/y; P = 0.002), especially in the anterior hemorrhage group (1.3%/y vs. 5.1%/y; P = 0.019). The hazard ratio of surgical intervention for rebleeding with initial anterior hemorrhage was 0.11 (95% CI: 0.01-0.98; P = 0.048). In the nonsurgical group, the presence of hypertension shortened the time to subsequent hemorrhage (P = 0.004).

CONCLUSIONS

Surgical intervention may decrease the risk of rebleeding in hemorrhagic onset MMD patients, even in those presenting with anterior hemorrhage. Hypertension was a significant risk factor for rebleeding in nonsurgical patients.

Adult Moyamoya Disease and Syndrome: Current Perspectives and Future Directions: A Scientific Statement From the American Heart Association/American Stroke Association

Adult moyamoya disease and syndrome are rare disorders with significant morbidity and mortality. A writing group of experts was selected to conduct a literature search, summarize the current knowledge on the topic, and provide a road map for future investigation. The document presents an update in the definitions of moyamoya disease and syndrome, modern methods for diagnosis, and updated information on pathophysiology, epidemiology, and both medical and surgical treatment. Despite recent advancements, there are still many unresolved questions about moyamoya disease and syndrome, including lack of unified diagnostic criteria, reliable biomarkers, better understanding of the underlying pathophysiology, and stronger evidence for treatment guidelines. To advance progress in this area, it is crucial to acknowledge the limitations and weaknesses of current studies and explore new approaches, which are outlined in this scientific statement for future research strategies.

Women and Ischemic Stroke

Although men are at higher risk of stroke throughout most of their lifespan, the incidence of stroke in women climbs with age, increasing after menopause and rising sharply after 85 years. This, combined with women's longer life expectancy, results in most of the stroke deaths occurring in women. In addition to accounting for a larger proportion of strokes, women may also suffer a survival disadvantage, which may be due to several factors. In many families, women are the primary caretakers. When they become disabled, there may be limited options to care for them. Others suggest that some of the disparities in stroke outcomes in women may be related to age, pre-stroke functional status, and comorbidities. Regardless of the cause, the increased disability and post-stroke care requirements of women, particularly in our aging population, highlight the importance of determining successful strategies for stroke prevention, acute stroke treatments, optimization of stroke rehabilitation, and effective secondary prevention measures in women.

Potential predictors for progression of moyamoya disease: A systematic review and meta-analysis

Background

The progress of Moyamoya disease (MMD) is often accompanied by the occurrence of new ischemia or hemorrhagic events, which was difficult to predict. This systematic review and meta-analysis aimed to identify predictors for progression in MMD patients.

Methods

We searched PubMed, Web of Science, Cochrane Library, and Embase databases up to December 10th, 2022 for randomized controlled trials, case-control studies, or cohort studies reporting predictors of disease progression in MMD patients. The results of each predictor were pooled by meta-analysis and further analyzed by subgroup analysis for predictors of unilateral to bilateral progression of MMD.

Results

A total of 842 patients from 12 studies were included. The estimated pooled means indicated lower age (standard mean difference [SMD]: -0.29, 95% confidence interval [CI]: -0.55 to -0.03; P = 0.03), family history (odds ratio [OR] 3.97, 95% CI: 1.96 to 8.03; P < 0.001) and contralateral abnormality (OR 3.95, 95% CI: 1.10 to 14.20; P = 0.04) were associated with progression in MMD patients. Subgroup analyses indicated that the same three factors were associated with the progression of unilateral to bilateral MMD.

Conclusions

This meta-analysis revealed that lower age, family history and contralateral abnormality were associated with progression in MMD patients. The same three factors are associated with the progression of unilateral to bilateral MMD. Further studies are needed to validate our results.

A Retrospective Study on Clinical Features of Childhood Moyamoya Disease

BACKGROUND

Childhood moyamoya disease (MMD) can lead to progressive and irreversible neurological impairment. Early age at onset is likely associated with a worst prognosis of the disease. The study aims to summarize the clinical characteristics of childhood MMD for supporting the diagnosis and treatment of early MMD.

METHODS

A retrospective study was conducted on children aged zero to 16 years who were diagnosed with MMD in the Department of Neurology and neurosurgery of our hospital from October 2016 to April 2020. The clinical characteristics of children with MMD were summarized for analysis, and the distribution of sex and initial attack type among different age groups was determined by data comparison.

RESULTS

The study surveyed 114 children (male to female sex ratio of 1:1.07) with MMD, and 6.1% of them had family history. The mean age of onset was 7.15 ± 3.30 years, and the peak age of onset was five to eight years. The most common initial attack type was transient ischemic attack (TIA) (62 cases, 54.4%) with limb weakness. The incidence of the initial attack type in the three age groups was varied (P < 0.05). The result of overall prognosis was good in 86 cases (89.6%).

CONCLUSIONS

In this study, MMD cases were mainly ischemic type and TIA was the most common initial attack type. Infant group was more prone to have cerebral infarction, whereas preschool and school-age groups tended to have TIA. The treatments and prognosis of the studied MMD cases were achieved with good outcomes.

Seizures, Epilepsy, and Electroencephalography Findings in Pediatric Moyamoya Arteriopathy: A Scoping Review

BACKGROUND

Although seizures are known to occur in children with moyamoya arteriopathy, data regarding characteristics, prevalence, and predictive factors for their development are less established. This study aimed to systematically review literature addressing seizures, epilepsy, and electroencephalography findings in the pediatric moyamoya population.

METHODS

A scoping review was performed by searching PubMed and Ovid:Embase databases for articles that described seizures, epilepsy, and electroencephalography findings in patients aged 0 to 21 years with moyamoya arteriopathy.

RESULTS

The search yielded 43 total articles that addressed the following topics in childhood moyamoya: seizures as the presenting symptom, epilepsy characteristics and management, characteristic electroencephalography findings including rebuildup with discussion of proposed mechanisms, and potential predictive clinical factors for the development of seizures preoperatively and the persistence of epilepsy postoperatively. In the reviewed literature, 9% to 19% of children with moyamoya had epilepsy, with over half of the cases lacking radiographic evidence of ischemia. Young age was the most consistent clinical factor associated with both seizures as the presenting symptom and with moyamoya-related epilepsy. Multiple studies report that seizures, electroencephalographic background abnormalities, and the rebuildup phenomenon improve after successful revascularization surgery.

CONCLUSIONS

This scoping review provides a thorough investigation of the literature available to date on the clinical features of seizures in the pediatric moyamoya population. Literature on this topic is scarce and further studies assessing predictive factors for the development of epilepsy, prognosis as a result of having seizures, and seizure management in this population will help to fill existing knowledge gaps.

Research progress of moyamoya disease combined with renovascular hypertension

Moyamoya disease (MMD) is an idiopathic cerebrovascular disease which was first described by Suzuki and Takaku in 1969. Moyamoya disease is a non-atherosclerotic cerebrovascular structural disorder. MMD has been found all over the world, especially in Japan, Korea, and China. In recent years, many reports pointed out that the changes of vascular stenosis in patients with moyamoya disease occurred not only in intracranial vessels, but also in extracranial vessels, especially the changes of renal artery. Renovascular hypertension (RVH) is considered to be one of the important causes of hypertension in patients with moyamoya disease. The pathogenesis of moyamoya disease combined with renovascular hypertension is still unclear, and the selection of treatment has not yet reached a consensus. This article reviews the latest research progress in epidemiology, RNF213 gene, pathomorphology, clinical characteristics and treatment of moyamoya disease combined with renovascular hypertension, in order to provide reference for clinical workers.

Mystery(n) Phenotypic Presentation in Europeans: Report of Three Further Novel Missense RNF213 Variants Leading to Severe Syndromic Forms of Moyamoya Angiopathy and Literature Review

Moyamoya angiopathy (MMA) is a rare cerebral vasculopathy in some cases occurring in children. Incidence is higher in East Asia, where the heterozygous p.Arg4810Lys variant in RNF213 (Mysterin) represents the major susceptibility factor. Rare variants in RNF213 have also been found in European MMA patients with incomplete penetrance and are today a recognized susceptibility factor for other cardiovascular disorders, from extracerebral artery stenosis to hypertension. By whole exome sequencing, we identified three rare and previously unreported missense variants of RNF213 in three children with early onset of bilateral MMA, and subsequently extended clinical and radiological investigations to their carrier relatives. Substitutions all involved highly conserved residues clustered in the C-terminal region of RNF213, mainly in the E3 ligase domain. Probands showed a de novo occurring variant, p.Phe4120Leu (family A), a maternally inherited heterozygous variant, p.Ser4118Cys (family B), and a novel heterozygous variant, p.Glu4867Lys, inherited from the mother, in whom it occurred de novo (family C). Patients from families A and C experienced transient hypertransaminasemia and stenosis of extracerebral arteries. Bilateral MMA was present in the proband’s carrier grandfather from family B. The proband from family C and her carrier mother both exhibited annular figurate erythema. Our data confirm that rare heterozygous variants in RNF213 cause MMA in Europeans as well as in East Asian populations, suggesting that substitutions close to positions 4118–4122 and 4867 of RNF213 could lead to a syndromic form of MMA showing elevated aminotransferases and extracerebral vascular involvement, with the possible association of peculiar skin manifestations.

Global disease burden of stroke attributable to high fasting plasma glucose in 204 countries and territories from 1990 to 2019: An analysis of the Global Burden of Disease Study

BACKGROUND

High fasting plasma glucose (HFPG) is the leading risk factor contributing to the increase of stroke burden in the past three decades. However, the global distribution of stroke burden specifically attributable to HFPG was not studied in depth. Therefore, we analyzed the HFPG-attributable burden in stroke and its subtypes in 204 countries and territories from 1990 to 2019.

METHODS

Detailed data on stroke burden attributable to HFPG were obtained from the Global Burden of Disease Study 2019. The numbers and age-standardized rates of stroke disability-adjusted life years (DALYs), deaths, years lived with disability, and years of life lost between 1990 and 2019 were estimated by age, sex, and region.

RESULTS

In 2019, the age-standardized rate of DALYs (ASDR) of HFPG-attributable stroke was 354.95 per 100 000 population, among which 49.0% was from ischemic stroke, 44.3% from intracerebral hemorrhage, and 6.6% from subarachnoid hemorrhage. The ASDRs of HFPG-attributable stroke in lower sociodemographic index (SDI) regions surpassed those in higher SDI regions in the past three decades. Generally, the population aged over 50 years old accounted for 92% of stroke DALYs attributable to HFPG, and males are more susceptible to HFPG-attributable stroke than females across their lifetime.

CONCLUSIONS

Successful key population initiatives targeting HFPG may mitigate the stroke disease burden. Given the soaring population-attributable fractions of HFPG for stroke burden worldwide, each country should assess its disease burden and determine targeted prevention and control strategies.

Causes of ischemic stroke in young adults versus non-young adults: A multicenter hospital-based observational study

Background

Very few comparative studies have focused on the differences in the causes of ischemic stroke between young adults and non-young adults. This study was performed to determine what causes of ischemic stroke are more important in young adults than in non-young adults using a large-scale multicenter hospital-based stroke registry in Fukuoka, Japan.

Methods and results

We investigated data on 15,860 consecutive patients aged ≥18 years with acute ischemic stroke (mean age: 73.5 ± 12.4 years, 58.2% men) who were hospitalized between 2007 and 2019. In total, 779 patients were categorized as young adults (≤50 years of age). Although vascular risk factors, including hypertension, diabetes mellitus, and dyslipidemia, were less frequent in young adults than in non-young adults, the prevalence of diabetes mellitus and dyslipidemia in young adults aged >40 years were comparable to those of non-young adults. Lifestyle-related risk factors such as smoking, drinking, and obesity were more frequent in young adults than in non-young adults. As young adults became older, the proportions of cardioembolism and stroke of other determined etiologies decreased, but those of large-artery atherosclerosis and small-vessel occlusion increased. Some embolic sources (high-risk sources: arterial myxoma, dilated cardiomyopathy, and intracardiac thrombus; medium-risk sources: atrial septal defect, nonbacterial thrombotic endocarditis, patent foramen ovale, and left ventricular hypokinesis) and uncommon causes (vascular diseases: reversible cerebral vasoconstriction syndrome, moyamoya disease, other vascular causes, arterial dissection, and cerebral venous thrombosis; hematologic diseases: antiphospholipid syndrome and protein S deficiency) were more prevalent in young adults than in non-young adults, and these trends decreased with age.

Conclusions

Certain embolic sources and uncommon causes may be etiologically important causes of ischemic stroke in young adults. However, the contribution of conventional vascular risk factors and lifestyle-related risk factors is not negligible with advancing age, even in young adults.

Comparison of Stroke Risk Factors Between Symptomatic and Asymptomatic Patients in a North American Moyamoya Disease Cohort

Background

Risk factors for stroke in symptomatic and asymptomatic moyamoya disease (MMD) patients have recently been reported in a Japanese cohort. Such information in a North American population is lacking.

Objective

We sought to elucidate the prevalence of stroke risk factors among North American patients with ischemic, hemorrhagic, and asymptomatic MMD.

Methods

We retrospectively reviewed our institution's database between 1990 and 2021. We excluded cases of moyamoya syndrome. We divided 119 patients into 3 groups based on the onset pattern; ischemic, hemorrhagic, and asymptomatic. We compared the prevalence of well-known stroke risk factors (diabetes, hypertension, etc.) between these three groups of patients. In the asymptomatic group, we analyzed the prevalence of cerebrovascular events on follow-up from the time of diagnosis.

Results

Overall, 119 patients with MMD were available with predominately White ethnicity (80.7%). The mean age was 39 years, and 73.9% were female. Patients presented with ischemic stroke (82%) and hemorrhagic stroke (11%); 7% of patients were asymptomatic. The prevalence of stroke risk factors did not differ among ischemic, hemorrhagic, or asymptomatic MMD patients. In 8 asymptomatic patients, there was 81.8 months (SD ±51.0) of follow-up, and none of them developed any cerebrovascular events.

Conclusions

No significant differences in the prevalence of stroke risk factors between MMD cohorts were found, corroborating evidence provided in a recent Japanese-based study. There were no apparent associations between stroke risk factors and interval cerebrovascular events in an asymptomatic group of MMD patients.

Epigenome-Wide Association Study Reveals Differential Methylation Sites and Association of Gene Expression Regulation with Ischemic Moyamoya Disease in Adults

Background

The association of DNA methylation with the pathogenesis of adult ischemic moyamoya disease (MMD) is unknown. Here, we investigated the genome-wide DNA methylation profiles in patients with MMD and identified the genes related to the pathogenesis of MMD.

Methods

Whole blood samples were collected from 20 individuals, including 10 patients with ischemic moyamoya disease without any underlying disease and 10 healthy individuals. Genome-wide DNA methylation analysis was performed using Illumina 850K microarrays. Transcriptional correlation was verified using quantitative reverse transcription-polymerase chain reaction. In vitro experiments were used to analyze the association of functional defects with candidate epigenetic markers.

Results

The genome-wide methylation level in the whole blood of adults with ischemic MMD was higher than that in the healthy individuals. In total, 759 methylation probes differed significantly between the case and control. The hypermethylated regions were mostly concentrated in the gene spacer regions. Among genes with the highest degree of the differential expression, KCNMA1 and GALNT2 were upregulated, whereas SOX6 and RBM33 were downregulated.

Conclusions

This is the first study showing that the low expression of genes associated with epigenetic regulation, such as SOX6 and RBM33, may be related to vascular occlusion in MMD, whereas the overexpression of KCNMA1 and GALNT2 may be related to the vascular hyperplasia. The results suggest that DNA methylation was involved in the pathogenesis of MMD, and new pathogenic genes were proposed as biological markers.

Epidemiology of Moyamoya Angiopathy in Eastern India

Introduction

Moyamoya angiopathy (MMA) is a chronic, progressive intracranial vasculopathy with variation in prevalence and clinical manifestations across different populations. This study was aimed to estimate the frequency of MMA as an etiology of stroke and its epidemiological features in the largest cohort of MMA patients in India.

Method

A single-centered cross-sectional observational study over a period of 5 years (2016–2021) was undertaken among consecutive stroke and transient ischemic attack (TIA) patients to look for the presence of MMA angiographically. Each patient with angiographically proven MMA was further evaluated for demographic, clinical, and radiological characteristics.

Results

Among 10,250 consecutive stroke and TIA patients (ischemic = 78%, hemorrhagic = 22%), frequency of MMA was 1.56% (n = 160); 15.3% among children. Female preponderance (Male:Female = 1:1.4) was noted among 160 MMA patients, with bimodal age distribution, first peak at 3–8 years, and a shorter second peak at 41–47 years. Childhood-onset MMA was seen in 75 (46.9%) with commonest initial neurological symptom of fixed-motor-weakness (44.0%), followed by TIA (26.7%); while 85 (53.1%) had adult-onset MMA with fixed-motor-weakness (50.6%) followed by headache (24.7%) as the predominant initial neurological symptom; seizure significantly higher in children (p < 0.001) and headache in adults (p = 0.012). Transient and fixed neurological manifestations constituted 87.5 and 69.4% respectively, of symptoms throughout the disease course. Cerebral infarction (45.0%) and TIA (21.9%) were the commonest types of MMA. On brain imaging, infarction was noted in 80.6%, hemorrhage in 11.3%, significantly higher among adults (p < 0.001). Cortical infarct and Gyral pattern were commoner in children (p = 0.004), subcortical infarcts in adults (p = 0.018). Frequent Suzuki staging observed was stage 4 (31.3%), followed by stage 3 (30.0%). Involvement of posterior circulation was detected in 55.6%, brain atrophy at the time of diagnosis was seen in 65.0%.

Conclusion

MMA is an important etiological consideration in patients with stroke, especially in children. It can present with a myriad of transient neurological symptoms, frequently overlooked, leading to delayed diagnosis, and contributing to socio-economic burden. Indian MMA showed aberrations in its gender predisposition, age distribution, frequency of familial cases, disease manifestation, and type of stroke, in comparison to its Japanese and Caucasian counterparts pointing to the inter- and intra-continent differences of MMA phenotype. Future development of the Indian MMA national registry is of essence.

Epidemiology of Moyamoya disease in China: A nationwide hospital-based study

Background

The national epidemiologic data in mainland China is still absent for moyamoya disease (MMD).

Methods

This study was a nationwide hospital-based observational retrospective study to estimate epidemiological characteristics of MMD. The data was based on the Hospital Quality Monitoring System (HQMS), a national database which covers all tertiary hospitals in mainland China. This system consistently collects medical records including demographic characteristics, diagnoses, procedures, and expenses etc. for all inpatients. MMD was identified by ICD-10 code (I67·5) in HQMS.

Findings

A total of 47,443 new-onset patients with total 69,680 hospitalization records from 1312 hospitals during 2016 to 2018 were included. The annual incidence rate was 1·14 per 100,000 inhabitants (95% CI, 1·12–1·16) and approximately a 2-fold increase from 2016 to 2018. The incidence in children (0·18 per 100,000 inhabitants per year; 95% CI, 0·17–0·20) was significantly lower than that in adults (1·40 per 100,000; 95% CI, 1·38–1·42) (P<0·001) and the peak incidence was 45–54 years. The distribution model of incidence rate was presented as a clustered regional pattern (Moran's I = 0·155, P = 0·018, Z = 2·375) by global spatial correlation analysis.

Interpretation

Our study reported the annual incidence of MMD was 1·14 per 100,000 inhabitants in mainland China during 2016 to 2018, and it was increasing year by year. The geographical distribution of MMD incidence presented as a clustered regional pattern, which may provide new view for future study on the etiology for MMD.

Funding

National Natural Science Foundation of China and “13th Five-Year Plan” National Science and Technology Supporting Plan.

Surgical revascularization vs. conservative treatment for adult hemorrhagic moyamoya disease: analysis of rebleeding in 322 consecutive patients

Whether surgical revascularization can prevent recurrent hemorrhage in hemorrhagic moyamoya disease (HMD) patients remains a matter of debate. This study mainly aims at the comparison of treatment effect between surgical revascularization and conservative treatment of adult HMD patients. We retrospectively enrolled 322 adult HMD patients, including 133 in revascularization group and 189 in conservative group. The revascularization group included patients who underwent combined (n = 97) or indirect revascularization alone (n = 36). Ninety-two and forty-one patients underwent unilateral and bilateral revascularization respectively. The modified Rankin scale (mRS) was used to assess the functional status. The comparison was made based on initial treatment paradigm among two categories: (1) revascularization vs. conservative, (2) unilateral vs. bilateral revascularization. The rebleeding rate was significantly lower in revascularization group than that in conservative group (14.3% vs. 27.0%, P = 0.007). As for the functional outcomes, the average mRS was significantly better in revascularization group (1.7 ± 1.5) than that in conservative group (2.8 ± 1.9) (P < 0.001). The death rate in revascularization group was 8.3% (11/133), comparing to 20.1% (38/189) in conservative group (P = 0.004). While comparing between unilateral and bilateral revascularization within the revascularization group, the result demonstrated lower annual rebleeding rate in bilateral group (0.5%/side-year) than that in unilateral group (3.3%/side-year) (P = 0.001). This study proved the better treatment efficacy of surgical revascularization than that of conservative treatment in HMD patients, regarding both in rebleeding rate and mortality rate. Furthermore, bilateral revascularization seems more effective in preventing rebleeding than unilateral revascularization.

Long-term mortality in patients with moyamoya angiopathy according to stroke presentation type in South Korea

BACKGROUND

Incidence, prevalence, and long-term survival outcomes in patients with moyamoya angiopathy (MMA) according to stroke presentation type and age group have not been clearly elucidated.

METHODS

We investigated mortality in patients with MMA (moyamoya disease, probable moyamoya disease, moyamoya syndrome) of whose International Classification Disease 10 code was I67.5 from 2006 to 2015 using the Korean National Health Insurance database. MMA at diagnosis was classified into 3 types (ischemic, hemorrhagic, and asymptomatic or else) according to stroke presentation. Survival analysis was performed according to stroke presentation type and age group (< 15 years and ≥ 15 years) using the Kaplan-Meier method.

RESULTS

There were 12,146 newly diagnosed moyamoya cases, with a female-to-male ratio of 1.81; the ischemic type was identified in 3671 (30.2%) patients, the hemorrhagic type in 2449 (20.2%) patients, and the asymptomatic or else type in 6026 (49.6%) patients. The mean age at diagnosis according to stroke presentation was 33.1 (± 14.8) years in asymptomatic or else type, 41.2 (± 17.3) years in ischemic type, and 45.4 (± 14.3) years in hemorrhagic type (P < 0.001). The 10-year survival rates in ischemic-, hemorrhagic-, and asymptomatic or else-type patients were 88.9%, 76.3%, and 94.3%, respectively (log-rank test; P < 0.001). Pediatric MMA (< 15 years) and adult MMA (≥ 15 years) showed different survival curves according to stroke presentation type (log-rank test; P = 0.017, P < 0.001, respectively).

CONCLUSIONS

Our study showed that moyamoya patients had different diagnosis ages and distinct survival courses according to stroke presentation type. Adult moyamoya patients with hemorrhagic presentation had the worst survival outcomes.

Epidemiology of symptomatic ossification of the posterior longitudinal ligament: a nationwide registry survey

BACKGROUND

Ossification of the posterior longitudinal ligament (OPLL) is radiographically detectable in 3-6% of Asian individuals, although not all detectable OPLL cases lead to myelopathy. To date, it is unknown how many patients suffer from neurological symptoms due to OPLL. The purpose of this study was to investigate the epidemiology of symptomatic OPLL using Japan's national registry database.

METHODS

We examined the registry data of patients with OPLL who held a certificate of medical subsidy from the Japanese Ministry of Health, Labor and Welfare. The study period was from January 1, 2011 to December 31, 2012.

RESULTS

Registry data revealed that the incidence and the period prevalence of symptomatic OPLL were 0.005% (5 per 100,000 population) and 0.027% (27 per 100,000 population), respectively. OPLL occurred twice as often in men as in women. The peak age for onset of symptoms was 60-69 years. The mean Japanese Orthopedic Association (JOA) score was 9 points. Ninety percent of OPLL patients underwent surgery, and 90% of these surgeries were performed with a posterior approach. The most common indication for surgery was a JOA score of 11 points.

CONCLUSIONS

According to registry data, the prevalence of symptomatic OPLL was less than one-hundredth of that of radiographically detected OPLL. This indicates that most cases of radiographically detectable OPLL may be asymptomatic.

Moyamoya disease: a case report of hemorrhagic stroke

This case report describes a patient with a rare cerebrovascular pathology — Moyamoya disease. The disease was manifested by acute hemorrhagic stroke.

An ecological comparison study on the causal association between leptospirosis and moyamoya disease in Hubei, China, 2017-2019

OBJECTIVE

The importance of environmental factors (especially leptospirosis) of moyamoya disease (MMD) has not been clarified. Here we investigated the epidemiological characteristics of MMD in Hubei province, China.

METHODS

We conducted a population-based study to describe the epidemiologic characteristics of MMD in Hubei province between 2017 and 2019. The regional clusters of the hot spots (high incidence) and cold spots (low incidence) of MMD were identified using the spatial statistical method. To evaluate the role of leptospirosis in MMD, we performed an ecological comparison study to evaluate whether the socioeconomic and environmental variables of hot spots are more suitable for leptospirosis spread.

RESULTS

The average annual sex and age adjusted incidence of MMD was 3.07 per 100,000 person-years from 2017 to 2019. The middle-aged had apparently higher incidence of MMD than the children. There existed an obvious geographic distribution difference of MMD at county level. The hot spots were identified mainly in the low mountainous and hilly terrain, while cold spots were located in the Jianghan Plains. Compared to cold spots, the hot spots had larger cattle density (32.0 vs 3.1, p = 0.002), higher percentages of rice field (85.6% vs 47.0%, p = 0.007), and lower elevation (33.6 vs 157.4, p < 0.001) CONCLUSIONS: There exists geographic distribution difference of MMD in Hubei province and was likely to be caused by leptospirosis in the early years. The MMD in China is dominant by middle-aged adults, which might be driven from leptospirosis outbreaks in the last century.

Metabolic Adjustments by LncRNAs in Peripheral Neutrophils Partly Account for the Complete Compensation of Asymptomatic MMD Patients

BACKGROUND

Due to the recent development of non-invasive examinations, more asymptomatic patients with Moyamoya Disease (MMD) have been diagnosed than ever. However, its underlying molecular mechanisms and clinical intervention guidelines are all still obscure.

METHODS

Microarray was used to explore those differentially expressed mRNAs and lncRNAs in peripheral neutrophils of asymptomatic MMD patients. Then enrichment analyses based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) for those differentially expressed mRNAs and lncRNA associated mRNAs were performed for underlying molecular mechanisms.

RESULTS

Here, we identified a total of 2824 differentially expressed lncRNAs and 522 differentially expressed mRNAs (fold change > 2 and P<0.05) in peripheral neutrophils of asymptomatic MMD patients, compared with healthy controls. Then enrichment analyses based on GO and KEGG showed that the neighboring protein-coding mRNAs of those up-regulated and down-regulated lncRNAs were mainly involved in distinct metabolic processes respectively, which may act as a complementary response to insufficient blood supplies in MMD. Further enrichment analyses of those differentially expressed mRNAs preferentially listed essential physiological processes such as peptide cross-linking, chromatin assembly among others. Moreover, altered mRNAs also revealed to be enriched in renin secretion, platelet activation, inflammation and others.

CONCLUSION

We demonstrated for the first time that metabolic adjustments by dysregulated lncRNAs in peripheral neutrophils might partially account for the complete compensation of asymptomatic MMD patients. In addition, more attention should be paid on renin secretion and platelet activation in order to better understand the pathogenesis and guide clinical intervention for asymptomatic MMDs.

Pediatric Acute Ischemic Stroke by Age-Group: A Systematic Review and Meta-Analysis of Published Studies and Hospitalization Records

BACKGROUND

Although stroke is rare among the pediatric population, it is nevertheless associated with serious or life-threatening consequences. The etiologic factors of acute ischemic stroke (AIS) are likely to vary over the course of childhood development. The incidence rates of AIS, not previously systematically examined by pediatric age subgroup, could guide studies of its etiology.

OBJECTIVE

The aim of this study is to evaluate the incidence rate of AIS by age-group in the pediatric population (aged 0-17/18 years) and identify any common trends or sources of variability across different countries.

METHODS

Rates of pediatric AIS were collated from a systematic literature review of published studies globally (1983-2020) and hospitalization records from Europe and the USA (2015-2018). Records that were included in the analysis reported the code or description used for AIS diagnosis and age-specific data for children aged 0-17/18 years. AIS incidence rates were summarized by age-group, data source, country, and geographic region. A meta-analysis was conducted to assess the heterogeneity of AIS rates in neonates.

RESULTS

The pooled AIS incidence rate was 5.6 per 100,000 children across all records. When only records reporting the AIS incidence rates for children across the full age range (0-17/18 years) were analyzed, the pooled AIS incidence rate was 4.6 per 100,000 children and ranged from 7.0 per 100,000 (Germany) to 1.3 per 100,000 (Denmark). The highest pooled rates were observed in the 0-28-day age-group (24.6 per 100,000 live births), declining to the lowest rates in the 5-9-year age-group, and rising again in the 10-17/18-year age-group. AIS rates were the most heterogeneous in the 0-28-day age-group and across European countries. Significantly higher AIS rates in neonates were observed from hospital databases (35.9 per 100,000) than in the literature (19.4 per 100,000). AIS rates may be underestimated as pediatric AIS events are rare and challenging to diagnose, and limited age-specific data are available.

CONCLUSIONS

Incidence rates of pediatric AIS by age-groups followed a consistent overall pattern of a reverse J-shaped curve, with the highest rates in neonates, across predominantly European and North American countries. Further research is warranted to examine if this pattern is observed in other geographic regions and to identify AIS risk factors specific to different phases of childhood development.

Progression in Moyamoya Disease: Clinical Feature, Neuroimaging Evaluation and Treatment

Moyamoya disease (MMD) is a chronic cerebrovascular disease characterized by progressive stenosis of the arteries of the circle of Willis, with the formation of collateral vascular network at the base of the brain. Its clinical manifestations are complicated. Numerous studies have attempted to clarify the clinical features of MMD, including its epidemiology, genetic characteristics, and pathophysiology. With the development of neuroimaging techniques, various neuroimaging modalities with different advantages have deepened the understanding of MMD in terms of structural, functional, spatial, and temporal dimensions. At present, the main treatment for MMD focuses on neurological protection, cerebral blood flow reconstruction, and neurological rehabilitation, such as pharmacological treatment, surgical revascularization, and cognitive rehabilitation. In this review, we discuss recent progress in understanding the clinical features, in the neuroimaging evaluation and treatment of MMD.

Incidence and prevalence of moyamoya disease in urban China: a nationwide retrospective cohort study

BACKGROUND AND OBJECTIVE

Moyamoya disease (MMD) is an increasingly recognised cause of stroke, mainly described in East Asia. China is the largest nation in Asia, but few studies reported the epidemiology of MMD, especially at a national level. We aimed to estimate the incidence and prevalence of MMD in China.

METHODS

We performed a population-based study using data from the national databases of Urban Basic Medical Insurance between 2013 and 2016, covering approximately 0.50 billion individuals. MMD cases were identified by diagnostic code (International Classification of Diseases, 10th Revision I67.5) or related diagnostic text.

RESULTS

A total of 1987 MMD patients (mean age 44.45±14.30 years, female-to-male ratio 1.12) were identified, representing a national crude incidence of 0.59 (95% CI: 0.49 to 0.68) and a prevalence of 1.01 (95% CI: 0.81 to 1.21) per 100 000 person-years in 2016. Rates were higher in females than in males for the incidence (0.66 vs 0.52) and prevalence (1.05 vs 0.90). And the age-specific rates showed a bimodal distribution, with the highest peak in middle-aged group and the second peak in child group.

CONCLUSIONS

Our results confirm that MMD is relatively common in East Asians, but the rates in China were lower than those in other East Asian countries such as Japan and Korea. The unique epidemiological features, including a relatively weak female predominance and a shift in the highest peak of incidence from children to adults, revealed new sight into MMD. Further research is expected to explore the potential pathogenesis of MMD.

RNF213 gene polymorphism rs9916351 and rs8074015 significantly associated with moyamoya disease in Chinese population

Background

Gene polymorphism especially Ring Finger Protein 213 (RNF213) p.R4810K is one of the main cause of moyamoya disease (MMD) in Asian populations, especially among Japanese people. However, missense mutation may not explain the reduced frequency of MMD in Chinese patients. We performed a hospital based case-control study in a Chinese population to elucidate the possible underlying reasons.

Methods

Five gene polymorphism loci, namely, rs35692831, rs9916351, rs9913636, rs8074015 and rs112735431, were included. A total of 98 patients and 114 healthy controls were enrolled in the study. Genomic DNA was genotyped by Mass Array methods.

Results

A significant difference was observed between patients and healthy controls in rs9916351, rs9913636, and rs8074015 loci under three genotypes and allelic models (P<0.01). Logistic regression analysis revealed the significant differences under the dominant, recessive and additional model in rs9916351 [odds ratio (OR) =4.173, 95% confidence interval (CI): 2.290-7.606, P<0.001; OR =3.152, 95% CI: 1.585-6.267, P=0.001; OR =0.199, 95% CI: 1.727-3.764, P<0.001; respectively] and rs8074015 (OR =0.359, 95% CI: 0.206-0.627, P<0.001; OR =0.348, 95% CI: 0.148-0.81, P=0.015; OR =0.208, 95% CI: 0.311-0.703, P<0.001; respectively), even adjusting for age and gender. In addition, the haplotype rs9913636-rs8074015 under "GACG" showed significant association with MMD.

Conclusions

Our results had revealed the polymorphism of RNF213 rs9916351 and rs8074015 were significantly associated with MMD especially in Chinese population.

Hemorrhagic patterns and their risk factors in patients with moyamoya disease

BACKGROUND AND PURPOSE

The aim was to describe the profiles of hemorrhagic patterns of moyamoya disease (MMD) and analyze the risk factors in a large population.

METHODS

A total of 335 conservatively managed MMD patients with hemorrhage in our hospital were included in this cross-sectional study. The correlation between clinical and angiographic characteristics and hemorrhagic patterns (anterior or posterior hemorrhage) was assessed in the hemorrhagic hemisphere by univariate and multivariate logistic regression models. In addition, stratified analysis was performed.

RESULTS

The 335 hemorrhagic hemispheres (patients) comprised 179 (53.4%) anterior and 156 (46.6%) posterior hemorrhages. For all cases, age at onset [odds ratio (OR) 0.98; 95% confidence interval (CI) 0.96-1.00; P = 0.048] and choroidal anastomosis (OR 1.87; 95% CI 1.19-2.94; P = 0.007) were found by multivariate regression analysis to be negatively and positively associated with a significantly increased risk of posterior hemorrhage, respectively. After stratified analysis, hypertension (OR 0.37; 95% CI 0.14-0.97; P = 0.043) was identified by multivariate regression analysis as a risk factor for anterior hemorrhage in patients without dilation of choroidal anastomosis. On the other hand, choroidal anastomosis (OR 2.62; 95% CI 1.02-6.72; P = 0.045) and involvement of the posterior cerebral artery (OR 3.39; 95% CI 1.20-9.63; P = 0.022) were associated with significantly increased risk of posterior hemorrhage in children and young adults (<30 years of age).

CONCLUSIONS

A dynamic change in hemorrhagic patterns in MMD patients with increasing age at onset was observed. Choroidal anastomosis is a predictor of posterior hemorrhage. Hypertension is a risk factor for anterior hemorrhage in patients without extreme dilation of choroidal anastomosis.

A Survey of Microsurgical Technique for Extracranial-to-Intracranial Bypass

BACKGROUND

Extracranial-to-intracranial bypass surgery is a well-established technique that has been practiced for over 50 years. Since then, numerous technical variants have developed nationally and internationally.

OBJECTIVE

Based on a survey, to collect information on cerebrovascular bypass surgeons and their background, surgical volume, and technical steps of extracranial-to-intracranial bypasses with focus on superficial temporal artery to middle cerebral artery (STA-MCA) bypass.

METHODS

An electronic survey was distributed among bypass neurosurgeons. Responses were analyzed for national-international variations of STA-MCA bypass surgery techniques. The survey focused on the technical aspects of the surgery itself rather than patient selection or perioperative management.

RESULTS

Survey responses were collected from 51 neurosurgeons performing cerebrovascular bypass, from 11 different countries across North America, Europe, and Asia. The largest age block was early-to mid-career (66.7% aged 36-50 years). Most participating surgeons (80.40%) performed less than 20 bypasses annually, whereas a select few surgeons (3) performed more than 50 annually. The most common bypass was STA-M4 MCA bypass with a linear incision (34%) over the parietal branch (44%) and choosing an MCA recipient based on diameter (61.2%). The interrupted anastomosis technique was most common (74%).

CONCLUSIONS

The results of this electronic survey will help to identify common patterns in STA-MCA bypass surgery and will serve as a guide to other neurosurgeons to modify and improve their technique. Cerebrovascular bypass is still widely practiced, including by young neurosurgeons, who are actively learning from established masters who share their experience.

Metabolomic Profiling Revealed Potential Biomarkers in Patients With Moyamoya Disease

Metabolomics is increasingly used to observe metabolic patterns and disease-specific metabolic biomarkers. However, serum metabolite analysis of moyamoya disease (MMD) is rarely reported. We investigated serum metabolites in MMD and compared them with those of healthy controls (HCs) using a non-targeted gas chromatography-mass spectrometry (GC-MS) approach to identify metabolic biomarkers associated with MMD. Forty-one patients with MMD diagnosed by cerebral angiography and 58 HCs were recruited for our study. Comparative analyses (univariate, multivariate, correlation, heatmaps, receiver operating characteristi curves) were performed between MMD patients and HCs. Twenty-five discriminating serum metabolic biomarkers between MMD patients and HCs were identified. Compared with HCs, MMD patients had higher levels of phenol, 2-hydroxybutyric acid, L-isoleucine, L-serine, glycerol, pelargonic acid, L-methionine, myristic acid, pyroglutamic acid, palmitic acid, palmitoleic acid, stearic acid, octadecanamide, monoglyceride (MG) (16:0/0:0/0:0), and MG (0:0/18:0/0:0), and lower levels of L-alanine, L-valine, urea, succinic acid, L-phenylalanine, L-threonine, L-tyrosine, edetic acid, and oleamide. These metabolic biomarkers are involved in several pathways and are closely associated with the metabolism of amino acids, lipids, carbohydrates, and carbohydrate translation. A GC-MS-based metabolomics approach could be useful in the clinical diagnosis of MMD. The identified biomarkers may be helpful to develop an objective diagnostic method for MMD and improve our understanding of MMD pathogenesis.

[Modern trends in diagnosis and surgical treatment of moyamoya disease]

This review is devoted to moyamoya disease. It is a rare chronic steno-occlusive cerebrovascular disease. However, moyamoya disease is increasingly diagnosed by neurosurgeons in our country. Unlike atherosclerotic lesions of cerebral arteries, pathogenesis and course of this disease are much more complex and variable. Therefore, specialists often have certain difficulties in diagnosis, management and treatment of these patients. To date, a large number of surgical interventions have been proposed for the treatment of moyamoya disease. Revascularization approaches include direct procedures (extra-intracranial microanastomoses), indirect methods (synangioses) and combined revascularization. The purpose of the review is to systematize current literature data on the pathogenesis, diagnosis, clinical patterns and surgical treatment of patients with moyamoya disease. results Outcomes of surgical revascularization and the role of its various components in combined approach are under particular attention.