Moyamoya: An Update and Review

Experience of an interdisciplinary management for pediatric Moyamoya disease: application of a novel Hemispheric Surgical Score

PURPOSE

The primary purpose of this study was to develop and implement a novel Hemispheric Surgical Score to guide the treatment of pediatric patients with Moyamoya disease (MMD). Additionally, we aimed to describe a comprehensive flowchart for the evaluation, treatment, and follow-up of these patients and to share our experience with the interdisciplinary management of a large pediatric cohort at a referral pediatric hospital.

METHODS

We conducted a retrospective observational study using medical records of patients diagnosed with MMD at the Pediatric Hospital "Prof. Dr. Juan P. Garrahan" in Buenos Aires, Argentina, from July 2013 to July 2023. From July 2016 onward, data were analyzed prospectively following the implementation of the Hemispheric Surgical Score and the flowchart. Evaluations included clinical, MRI, and angiographic criteria, and patients were managed by an interdisciplinary team. Demographic, clinical, and neuroimaging data were collected and analyzed.

RESULTS

Eighty hemispheres from 40 patients were analyzed, with cerebral revascularization performed on 72 hemispheres from 37 patients. The Hemispheric Surgical Score and flowchart standardized treatment decisions, and reduced the need for invasive studies like angiographies for follow-up. The majority of patients (79.1%) had favorable outcomes, with complete disease progression arrest and no worsening of imaging nor clinical scores during a median follow-up of 35.8 months.

CONCLUSION

The Hemispheric Surgical Score and the comprehensive flowchart have improved the management of MMD in pediatric patients by standardizing treatment and reducing unnecessary invasive procedures. This interdisciplinary approach has led to better patient outcomes, highlighting the need for further validation in larger studies and comparisons of different revascularization techniques through randomized clinical trials.

Pregnancy Risk Assessment, Management, and Delivery Plan for Pregnant Women with Moyamoya Disease Using a Multidisciplinary Collaborative Approach: A Case Series

Purpose

This case report aimed to summarize the risk factors, clinical characteristics, imaging changes, and maternal and fetal prognosis associated with Moyamoya disease in pregnant women and to explore effective management strategies and a comprehensive delivery plan.

Case Presentation

The clinical data of four pregnant women who were diagnosed with Moyamoya disease and admitted to our hospital between January 2010 and January 2019 were retrospectively analyzed. Their diagnosis, treatment, delivery, and postpartum management during the pregnancy were analyzed. Among the four pregnant women, three were primipara and one was multipara. The age ranged from 27 to 41 years old. The gestational week of termination of pregnancy ranged between 8 and 39 weeks. During pregnancy, one case died in utero; one case was complicated with postpartum hemorrhage; one case was complicated with chronic hypertension, multiple cerebral artery stenosis and occlusion, bilateral middle cerebral artery occlusion, bilateral internal carotid artery occlusion, and Hashimoto's thyroiditis. Under epidural anesthesia, two cases underwent a lower segment cesarean section; one case underwent artificial abortion; and one case underwent induced labor during late pregnancy. Two newborns survived.

Conclusion

Moyamoya disease is a rare and serious complication of pregnancy. Pregnancy and childbirth may exacerbate the progression of this disease or induce cerebrovascular accidents, with a high mortality and disability rate, which seriously threatens the safety of mother and infant lives; however, with the close collaboration of a multidisciplinary team, it is possible to maximize a good pregnancy outcome.

Case Report: A rare presentation of rapidly progressive moyamoya disease refractory to unilateral surgical revascularization

Moyamoya disease (MMD) is a chronic, occlusive cerebrovasculopathy typified by progressive steno-occlusive disease of the intracranial internal carotid arteries (ICAs) and their proximal branches. Moyamoya syndrome (MMS) categorizes patients with characteristic MMD plus associated conditions. As such, the most usual presentations are those that occur with cerebral ischemia, specifically transient ischemic attack, acute ischemic stroke, and seizures. Hemorrhagic stroke, headaches, and migraines can also occur secondary to the compensatory growth of fragile collateral vessels propagated by chronic cerebral ischemia. While the pathophysiology of MMD is unknown, there remain numerous clinical associations including radiation therapy to the brain, inherited genetic syndromes, hematologic disorders, and autoimmune conditions. We describe the case of a 31-year-old woman who presented with recurrent ischemic cerebral infarcts secondary to rapidly progressive, bilateral MMD despite undergoing early unilateral surgical revascularization with direct arterial bypass. She had numerous metabolic conditions and rapidly decompensated, ultimately passing away despite intensive and aggressive interventions. The present case highlights that progression of moyamoya disease to bilateral involvement can occur very rapidly, within a mere 6 weeks, a phenomenon which has not been documented in the literature to our knowledge.

Risk Factors for Preoperative Cerebral Infarction in Infants with Moyamoya Disease

There have been few reports on the risk factors for preoperative cerebral infarction in childhood moyamoya disease (MMD) in infants under 4 years. The aim of this retrospective study is to identify clinical and radiological risk factors for preoperative cerebral infarction in infants under 4 years old with MMD, and the optimal timing for EDAS was also considered. We retrospectively analyzed the risk factors for preoperative cerebral infarction, confirmed by magnetic resonance angiography (MRA), in pediatric patients aged ˂4 years who underwent encephaloduroarteriosynangiosis between April 2005 and July 2022. The clinical and radiological outcomes were determined by two independent reviewers. In addition, potential risk factors for preoperative cerebral infarction, including infarctions at diagnosis and while awaiting surgery, were analyzed using a univariate model and multivariate logistic regression to identify independent predictors of preoperative cerebral infarction. A total of 160 hemispheres from 83 patients aged <4 years with MMD were included in this study. The mean age of all surgical hemispheres at diagnosis was 2.17±0.831 years (range 0.380-3.81 years). In the multivariate logistic regression model, we included all variables with P<0.1 in the univariate analysis. The multivariate logistic regression analysis indicated that preoperative MRA grade (odds ratio [OR], 2.05 [95% confidence interval [CI], 1.3-3.25], P=0. 002), and age at diagnosis (OR, 0.61 [95% CI, 0.4-0.92], P=0. 018) were predictive factors of infarction at diagnosis. The analysis further indicated that the onset of infarction (OR, 0.01 [95% CI, 0-0.08], P<0.001), preoperative MRA grade (OR, 1.7 [95% CI, 1.03-2.8], P=0.037), and duration from diagnosis to surgery (Diag-Op) (OR, 1.25 [95% CI, 1.11-1.41], P<0.001) were predictive factors for infarction while awaiting surgery. Moreover, the regression analysis indicated that family history (OR, 8.88 [95% CI, 0.91-86.83], P=0.06), preoperative MRA grade (OR, 8.72 [95% CI, 3.44-22.07], P<0.001), age at diagnosis (OR, 0.36 [95% CI, 0.14-0.91], P=0.031), and Diag-Op (OR, 1.38 [95% CI, 1.14-1.67], P=0.001) were predictive factors for total infarction. Therefore, during the entire treatment process, careful observation, adequate risk factor management, and optimal operation time are required to prevent preoperative cerebral infarction, particularly in pediatric patients with a family history, higher preoperative MRA grade, duration from diagnosis to operation longer than 3.53 months, and aged ˂3 years at diagnosis.

Evaluation of deep learning algorithms in detecting moyamoya disease: a systematic review and single-arm meta-analysis

The diagnosis of Moyamoya disease (MMD) relies heavily on imaging, which could benefit from standardized machine learning tools. This study aims to evaluate the diagnostic efficacy of deep learning (DL) algorithms for MMD by analyzing sensitivity, specificity, and the area under the curve (AUC) compared to expert consensus. We conducted a systematic search of PubMed, Embase, and Web of Science for articles published from inception to February 2024. Eligible studies were required to report diagnostic accuracy metrics such as sensitivity, specificity, and AUC, excluding those not in English or using traditional machine learning methods. Seven studies were included, comprising a sample of 4,416 patients, of whom 1,358 had MMD. The pooled sensitivity for common and random effects models was 0.89 (95% CI: 0.85 to 0.92) and 0.92 (95% CI: 0.85 to 0.96), respectively. The pooled specificity was 0.89 (95% CI: 0.86 to 0.91) in the common effects model and 0.91 (95% CI: 0.75 to 0.97) in the random effects model. Two studies reported the AUC alongside their confidence intervals. A meta-analysis synthesizing these findings aggregated a mean AUC of 0.94 (95% CI: 0.92 to 0.96) for common effects and 0.89 (95% CI: 0.76 to 1.02) for random effects models. Deep learning models significantly enhance the diagnosis of MMD by efficiently extracting and identifying complex image patterns with high sensitivity and specificity. Trial registration: CRD42024524998 https://www.crd.york.ac.uk/prospero/displayrecord.php?RecordID=524998.

Evaluation of paclitaxel-coated balloon angioplasty for the treatment of symptomatic intracranial in-stent restenosis

Background

Symptomatic intracranial in-stent restenosis (sISR) poses a major challenge in the management of cerebrovascular diseases, often requiring effective and safe treatment options.

Objectives

This study aims to evaluate the efficacy and safety of paclitaxel-coated balloon (PCB) angioplasty for treating sISR.

Methods

We conducted a retrospective analysis of five patients aged 49-74 years, who were treated with PCB angioplasty between January 2017 and June 2022. Treatment procedures included pre-operative digital subtraction angiography, antiplatelet therapy, and the use of the SeQuent Please balloon. Patients received aspirin and clopidogrel prior to and after the procedure.

Results

The procedure achieved a 100% success rate. The degree of ISR was significantly reduced from an average pre-operative rate of 72±18.9% to a post-operative rate of 34±8.22%. Long-term follow-up showed that the majority of patients did not experience restenosis, confirming the long-term effectiveness of the treatment.

Conclusions

PCB angioplasty demonstrates significant potential as an effective and safe treatment option for patients with sISR, especially those considered to be at high risk. This study supports further investigation into PCB angioplasty as a standard treatment for sISR.

Predictors of Stroke Outcomes in Conservatively Treated Patients With Moyamoya Disease: A Follow-up MRI Study

BACKGROUND

Little is known about the association between stroke and imaging and clinical features in conservatively treated patients with moyamoya disease (MMD).

PURPOSE

To investigate independent risk factors for stroke in conservatively treated patients with MMD during a long-term follow-up.

STUDY TYPE

Prospective study.

SUBJECTS

One hundred sixty conservatively managed patients with MMD (median age 46 years, 89 male).

FIELD STRENGTH/SEQUENCE

Time of flight, turbo inversion recovery magnitude T1WI, turbo spin echo (TSE) T2WI, echo-planar imaging DWI, T2-fluid attenuated inversion recovery, dynamic susceptibility contrast-magnetic resonance imaging, and pre- and post-contrast 3D TSE T1WI sequences at 3.0 Tesla.

ASSESSMENT

Patients were assessed at baseline and followed yearly. Ischemic and hemorrhagic stroke incidence rates were determined. Multiple demographic, clinical (modified Rankin score [mRS]), and cerebral imaging (cerebral blood volume [CBV] and concentric enhancement of arterial wall) factors at baseline were considered as potential predictors of stroke during the follow-up period.

STATISTICAL TESTS

Univariable and multivariable Cox proportional hazards models to calculate the hazard ratios (HRs) and corresponding 95% confidence interval (CI) for stroke. Cumulative risk of stroke was estimated by the Kaplan-Meier product-limit method. A P value <0.05 was considered statistically significant.

RESULTS

The median follow-up duration was 47 months. During the follow-up period, 18 (11.25%) patients experienced stroke events (13 [8.13%] ischemic, 5 [3.12%] hemorrhagic). Univariable analysis showed that 11 factors were significantly associated with stroke. After adjustment for clinical characteristics, multivariable analysis showed that mRS score ≥3 (HR, 1.99; 95% CI, 1.26-3.14), decreased CBV (HR, 5.31; 95% CI, 2.32-12.13), and concentric enhancement of the arterial wall (HR, 4.16; 95% CI, 1.55-11.15) were significantly associated with stroke.

DATA CONCLUSION

Decreased CBV, mRS score ≥ 3, and concentric enhancement of the arterial wall were significantly associated with increased incidence of stroke in conservatively treated MMD.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 4.

A Rare Case of Cardiac Myxoma With Moyamoya Phenomenon: A Disease or Syndrome?

Moyamoya disease (MMD) is a rare, idiopathic, progressive, obstructive, vasculopathy affecting primarily the terminal portions of the intracerebral internal carotid arteries, typically at the base of the brain. It is more commonly seen in people of East Asian descent. The moyamoya phenomenon refers to the characteristic appearance of the tangle of fine blood vessels, also described as a puff of smoke. Moyamoya syndrome (MMS) refers to the constriction-induced chronic brain ischemia that is believed to cause overexpression of proangiogenic factors, creating a fragile network of collateral capillaries. MMS refers to the moyamoya phenomenon in the presence of other congenital or acquired disorders. Intracerebral hemorrhage is the leading cause of death for MMS patients. Overall, the prognosis is variable. Cardiac myxoma can cause embolization of tumor cells, plaques, and thrombus, and recurrent thromboembolism can lead to chronic brain ischemia, which can lead to the development of collaterals. There have been cases reported where the moyamoya phenomenon resolved following myxoma resection. Here, we present the case of a female who had intraventricular bleeding and was diagnosed with MMD. Eighteen months later, she presented with shortness of breath and was diagnosed with cardiac myxoma with multiple valvular regurgitations. The myxoma was surgically removed.

Psychiatric manifestations in moyamoya disease: more than a puff of smoke? a systematic review and a case-reports meta-analysis

Introduction

Moyamoya disease (MMD) is a life-threatening condition characterized by stenosis of intracranial arteries. Despite the frequency and the impact of psychiatric symptoms on the long-term prognosis and quality of life of MMD patients, no systematic review on this topic exists.

Methods

This systematic review and meta-analysis included 41 studies (29 being case reports), from PubMed, Scopus, Embase until 27/3/2023, on MMD patients exhibiting psychiatric symptoms.

Results

Despite a fair average quality of the articles, quantitative synthesis through logistic regression was possible only for case reports, due to heterogeneity between the other studies. Psychosis, the most frequent psychiatric symptom reported in case reports, was more frequent in MMD patients with left hemisphere involvement. Neurological symptoms occurrence increased the odds of MMD diagnosis preceding psychiatric symptoms. Psychiatric symptoms are highly prevalent in MMD patients and are relatively often the only presenting symptoms.

Discussion

We discuss the diagnostic, therapeutic, and prognostic implications of recognizing and characterizing specific psychiatric symptoms in MMD, outlining preliminary guidelines for targeted pharmacological and psychotherapeutic interventions. Lastly, we outline future research and clinical perspectives, striving to enhance the oft-overlooked psychiatric care for MMD patients and to ameliorate their long-term outcome.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023406303.

Moyamoya Disease in a Patient With Sickle Cell Disease: A Case Report and Review of the Literature

Moyamoya disease (MMD) is a relatively rare, progressively worsening steno-occlusive condition primarily characterized by a progressive narrowing of the intracranial arteries, causing hypoperfusion and consequent cerebral ischemia and infarction. This case report discusses the rare presentation of a patient who was known to have sickle cell disease and MMD. Various investigations have revealed a typical presentation of such a disease through radiological findings. Our report highlights this rare disease and its possible association with other comorbidities, as well as the medical treatment options that patients may undergo with the option of surgical treatment.

Moya moya vasculopathy and MECP2 duplication syndrome

BACKGROUND

Moya moya type vasculopathy (MMV) is a rare disorder in which there is narrowing of bilateral intracranial carotid arteries (Scott and Smith in New Engl J Med 360(12):1226-1237, 2009). MECP2 duplication syndrome (MDS) is a rare genetic disorder that is caused by genetic duplications on Xq28 chromosome (Expanding the clinical picture of the MECP2 duplication syndrome. (Lim et al. in Clin Genet 91(4):557-563, 2017). Both disorders are rare and have not been described together in association.

CASE PRESENTATION

Interestingly, we present a child with both MDS and MMV. Upon genetic testing, there was found to be a large, de novo duplication sequence in the patient's genome. Possible correlation between our patient's extensive genetic mutation and MMV has been evaluated.

CONCLUSION

Our literature search disclosed no other known patients with both MDS and MMV. Patients with MDS should be monitored carefully for signs or symptoms of vasculopathy.

Encephaloduroarteriosynangiosis Procedure: A Treatment Option for Patients With Moyamoya Disease

Moyamoya disease is a progressive cerebrovascular disorder for which there is no cure. It is characterized by narrowing of and occlusions in the blood vessels that supply the brain, which causes a fine vascular network to develop to serve as collateral pathways. Moyamoya disease can lead to a reduction of blood flow to the brain and increase the risk of stroke. Patients with moyamoya disease may present with ischemic or hemorrhagic complications. Treatment options may involve medical management or surgical revascularization (indirect, direct, or a combined approach). The encephaloduroarteriosynangiosis procedure is a form of indirect revascularization in which a portion of the superficial temporal artery is moved from the scalp to the brain surface. Regardless of the approach, the goal of revascularization is to improve blood flow to the affected area to prevent additional infarcts; the encephaloduroarteriosynangiosis procedure is a viable option to help prevent additional neurologic decline.

Moya-Moya Disease Revealed by a Non-lobar Intracerebral Hemorrhage in an Adult

Moya-Moya disease (MMD) is a rare cerebral vasculopathy affecting children and adults. It is a progressive steno-occlusive arterial disease generally discovered during the etiological assessment of an ischemic or hemorrhagic stroke. Its diagnosis is based essentially on imaging. Cerebral digital subtraction angiography (DSA) remains the gold standard. We report the case of a 42-year-old male patient admitted for the loss of consciousness with a Glasgow Coma Scale (GCS) of 12/15. A brain CT scan revealed a right capsulo-lenticular hematoma with ventricular flooding and hydrocephalus. Cerebral CT angiography showed features of Moya-Moya vasculopathy, which was confirmed by a cerebral catheter angiogram.

[Moyamoya in Aragon: epidemiology and self-perception of quality of life]

INTRODUCTION

Moyamoya angiopathy is a vasculopathy caused by stenosis/occlusion of one or both intracranial internal carotid arteries. Although more common in Eastern countries, its prevalence is increasing in the West. An angioresonance or angiography is essential for its diagnosis. There are two options for treatment: conservative (medical) treatment or surgical bypass techniques.

PATIENTS AND METHODS

Nineteen patients were selected using International Classification of Diseases codes, and their demographic characteristics and health outcomes were studied. They were administered a scale for the screening of anxious-depressive syndrome (the Hospital Anxiety and Depression Scale - HADS) and another scale for self-perceived quality of life (SF-36). After applying the inclusion/exclusion criteria, eight of these patients were studied.

RESULTS

Nineteen patients were studied (52.63% male, 57.89% European) and the Aragonese prevalence was estimated at 1.37/100,000 inhabitants. The most frequent clinical presentation was ischaemic stroke (73.68%). The HADS detected two positive cases of anxiety and one case of depression. According to the SF-36, the worst self-rated aspects were vitality (median: 35/100) and general health (median: 42.5/100), while the best rated was physical function (mean: 93.57/100).

CONCLUSIONS

This is the Spanish series with the highest prevalence and the only one that addresses self-perceived health and screening of the anxious-depressive syndrome. Further research is needed to address this entity and determine its true prevalence in the West.

Diagnostic Yield of Bone Window Computed Tomography and Cerebral Angiography Testing Congenital Bilateral Hypoplasia of the Internal Carotid Artery

We herein report a case of congenital bilateral hypoplasia of the internal carotid artery (ICA) that was diagnosed by bone window computed tomography (CT) and cerebral angiography. A 23-year-old woman presented with left dominant quadriplegia. Brain magnetic resonance imaging showed not only massive infarcts in the anterior circulation but also poor depiction of the bilateral ICAs. Bilateral carotid canals on bone window CT suggested hypoplasia. Cerebral angiography revealed narrowing of each ICA above its bifurcation, and the blood supply to the intercranial carotid systems developed from the vertebrobasilar system through the posterior communicating arteries and posterior cerebral arteries. We diagnosed the patient with congenital bilateral hypoplasia of the ICA based on bone CT and cerebral angiography findings. Performing both bone window CT and cerebral angiography can facilitate the diagnosis of congenital hypoplasia of the ICA.

Nomogram for Predicting Long-term Outcomes of Encephaloduroarteriosynangiosis in Toddlers with Moyamoya Disease: a Longitudinal and Cross-sectional Study

We investigated the long-term outcomes of encephaloduroarteriosynangiosis (EDAS) for stroke prevention in toddlers with moyamoya disease (MMD) using nomogram. Between January 2005 and December 2018, 74 toddlers with MMD underwent surgery in the Fifth Medical Centre, Chinese PLA General Hospital, 69 were < 4 years of age and included in the analysis. The modified Rankin scale (mRS) during follow-up evaluated clinical outcomes. To measure the effectiveness of EDAS, the annual risk of symptomatic infarction within the operated brain hemispheres was calculated. The event-free survival rate was determined using Kaplan-Meier curves. A nomogram generated using multivariate logistic regression analysis identified potential predictors associated with unfavorable outcomes. Additionally, discrimination, calibration, and clinical utility were assessed. A favorable clinical outcome was observed in 81.2% of the patients. The operated hemispheres showed an annual risk of 0.87% of symptomatic infarction and 0.23% of hemorrhage. Moreover, the 10-year event-free survival rates were 92.8% and 97.0% for symptomatic infarction and hemorrhage. Multivariate logistic analysis indicated that onset with infarction, initial mRS ≥ 3, and perioperative adverse events had significant and independent associations with unfavorable outcomes. However, an age at diagnosis of ≥ 2 years showed an association with favorable outcomes. Using these four factors, our model attained a concordance index of 0.912 (95% confidence interval, 0.842-0.982), well-fitted calibration curve, and cutoff value of 0.212 for predicting unfavorable outcomes. EDAS may prevent recurrent stroke and improve overall long-term clinical outcomes in toddlers with MMD. The developed nomogram accurately predicted unfavorable outcomes and assisted surgeons in patient evaluation.

Moyamoya Syndrome in Children With Sickle Cell Disease in Saudi Arabia: A Single-Center Experience

Background Sickle cell disease (SCD) is relatively common in Saudi Arabia. Its neurologic complications such as stroke and Moyamoya syndrome (MMS) can be severe and devastating. Such complications can be minimized by modern investigative tools such as transcranial Doppler (TCD) ultrasound, which is unavailable in many high-risk places. Our aim is to investigate the prevalence and characteristics of these complications in children with SCD in our center where TCD is not available. Methods We conducted a retrospective record review of children with SCD admitted to the pediatric ward and visited the pediatric hematology outpatient clinic of King Fahad Military Medical Complex, Dhahran, Saudi Arabia, from January 2010 to December 2021. The target population was children aged six months to 14 years with SCD and a history of stroke or transient ischemic attacks (TIAs). Their magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) of the brain radiographic features were reviewed. A descriptive analysis was used to summarize the demographic characteristics and clinical features of patients with and without MMS. Results Twenty-six children (out of 385 with sickle cell anemia, originating mainly from the southwestern and eastern provinces of Saudi Arabia) experienced an overt stroke with an overall prevalence of 6.7%. All patients with stroke were originally from the Southwestern province. Their genotype was SS, and the median age at the onset of the first stroke was six years (IQR: 5.5). The main presenting symptoms were seizures (57.7%), motor weakness (42.3%), headache (15.3%), cranial nerve palsies (11.5%), cognitive deficit (7.6%), and dysphasia (3.8%). The majority of strokes were ischemic (92.3%). MMS was detected in 61.5% and was seen at the onset of the first stroke in all patients with this MRA abnormality. Seven children with moyamoya (43.8%) had recurrent strokes. Conclusion In this study, the prevalence of overt stroke is 9% in children with SCD originating from the southwestern region of Saudi Arabia (26/286), and 61.5% of them (16/26) had MMS. It is absent in the children of Eastern origin (99 children). In places lacking TCD facilities, further studies are required to determine if MRA brain screenings of children with SCD may detect MMS before the onset of stroke and help start protective therapy.

Recurrent Headaches and Moyamoya Syndrome in a Non-Asian Descendant: A Case Report

Moyamoya disease (MMD) is a rare yet progressive cerebrovascular disorder caused by the constriction of arteries, which leads to the twisting and tangling of small arteries in the brain, ultimately causing blockages. Although moyamoya angiopathy (MMA) has been known for almost six decades, its pathophysiology remains unknown, posing challenges to timely diagnosis. Moyamoya syndrome (MMS) refers to the association of MMA with various diseases, including infections, tumors, arteriovenous malformations, radiation treatment, and hereditary disorders. On the other hand, MMD, an idiopathic form, is now more frequently linked to genetic abnormalities. MMS is more common in people of Asian descent, but we encountered and aim to discuss a rare case of a 32-year-old Caucasian from Colombia who was diagnosed with it. The patient initially presented with unexplained symptoms of stroke, prompting doctors to conduct additional imaging. Fortunately, this led to her timely diagnosis. The report discusses the challenges that healthcare professionals face in diagnosis when presented with such uncommon cases. Through this case report, we try to review the presentation, diagnosis, and treatment used for this patient with MMS. The limited information available about the disease, especially the demographic data in countries outside Asia, often leads to delayed diagnoses, emphasizing the need for further exploration. Timelier diagnosis and heightened research into the disease's presentation and risk factors could lead to improved outcomes. Our report also briefly discusses the effectiveness of the current treatment protocol for patients. Currently, the patient is undergoing rehabilitation and showing promising progress.

A Rare Case of Moyamoya Disease in a Hispanic Woman: Unveiling Non-Asian Ethnicity and Atypical Risk Factors

BACKGROUND Moyamoya disease is a rare and progressive cerebrovascular disorder caused by narrowed or blocked arteries supplying the brain. First described in Japan, the disease's incidence is higher in Asian countries and primarily affects children, although adults can also be afflicted. Following a literature review, very little was found regarding non-Asian ethnicities and the lack of typically associated risk factors that are known correlates of Moyamoya disease. CASE REPORT We present the case of a 41-year-old Hispanic woman with a history of type 1 diabetes mellitus and asthma who presented to the Emergency Department with concerns of recurrent transient episodes of left upper extremity weakness and paresthesia followed by confusion. The patient's blood pressure on arrival was 215/134 mmHg, and heart rate was 124 beats per min. Computed tomography of the head was unremarkable, but a computed tomography angiogram of the head demonstrated several areas of severe and bilateral stenosis with radiographic appearances, suggestive of Moyamoya disease. Magnetic resonance imaging of the brain would later illustrate two 6×2-mm ischemic infarcts in the right posterior centrum semiovale. CONCLUSIONS Moyamoya disease in the non-Asian population is rarely reported. We present a case of this condition in a patient of Hispanic ethnicity. Although it is generally considered a non-atherosclerotic disease, some literature suggests that atherosclerotic disease may also contribute to the development and possible acceleration of clinical features of Moyamoya disease. Given our patient's risk factors, we postulated that our patient's presentation was likely multifactorial, with both non-sclerotic and atherosclerotic disease.

White and Gray Matter Perfusion in Children with Moyamoya Angiopathy after Revascularization Surgery

INTRODUCTION

Surgical revascularization is very effective in patients with moyamoya angiopathy (MMA) and leads to improvements in cortical perfusion parameters. However, changes in white matter hemodynamics are still underestimated. To date, only a few studies have examined brain perfusion changes within deep white matter after bypass surgery in patients with MMA.

METHODS

Ten children with MMA were evaluated using the CT perfusion technique before and after revascularization surgery. Brain perfusion parameters within gray and white matter were compared before and after surgery. The correlations between the perfusion parameters before surgery and the Suzuki stage, as well as between the perfusion parameters and the cognitive scores, were also evaluated.

RESULTS

Brain perfusion parameters improved significantly in both gray matter (predominantly due to cerebral blood flow within the anterior circulation, p < 0.01) and white matter (predominantly due to cerebral blood volume within the semiovale centrum, p < 0.001). We revealed that the pattern of improvement in perfusion in white matter differed from the pattern of improvement in perfusion in gray matter. Significant correlations were revealed between the Suzuki stage before surgery and the perfusion parameters within the posterior cerebral artery circulation (adjusted p < 0.05). There were also significant correlations between cognitive scores and brain perfusion parameters in gray matter and white matter (adjusted p < 0.05).

CONCLUSIONS

The perfusion parameters of gray matter and white matter in the brain improve differently after bypass surgery in patients with MMA. Different hemodynamics within these compartments could explain this.

Comparison of revascularization and conservative treatment for hemorrhagic moyamoya disease in East Asian Countries: a single-center case series and a systematic review with meta-analysis

Objective

The optimal treatment approach for hemorrhagic moyamoya disease (HMMD) remains a topic of debate, particularly regarding the comparative efficacy of revascularization versus conservative treatment. Our study, which included a single-center case series and a systematic review with meta-analysis, aimed to determine whether surgical revascularization is associated with a significant reduction in postoperative rebleeding, ischemic events, and mortality compared to conservative treatment among East Asian HMMD patients.

Methods

We conducted a systematic literature review by searching PubMed, Google Scholar, Wanfang Med Online (WMO), and the China National Knowledge Infrastructure (CNKI). The outcomes of surgical revascularization and conservative treatment, including rebleeding, ischemic events and mortality, were compared. The authors' institutional series of 24 patients were also included and reviewed in the analysis.

Results

A total of 19 East Asian studies involving 1,571 patients as well as our institution's retrospective study of 24 patients were included in the study. In the adult patients-only studies, those who underwent revascularization had significantly lower rates of rebleeding, ischemic events, and mortality compared to those who received conservative treatment (13.1% (46/352) vs. 32.4% (82/253), P < 0.00001; 4.0% (5/124) vs. 14.9% (18/121), P = 0.007; and 3.3% (5/153) vs. 12.6% (12/95), P = 0.01, respectively). In the adult/pediatric patients' studies, similar statistical results of rebleeding, ischemic events, and mortality have been obtained (70/588 (11.9%) vs. 103/402 (25.6%), P = 0.003 or <0.0001 in a random or fixed-effects model, respectively; 14/296 (4.7%) vs. 26/183 (14.2%), P = 0.001; and 4.6% (15/328) vs. 18.7% (23/123), P = 0.0001, respectively).

Conclusion

The current single-center case series and systematic review with meta-analysis of studies demonstrated that surgical revascularization, including direct, indirect, and a combination of both, significantly reduces rebleeding, ischemic events, and mortality in HMMD patients in the East Asia region. More well-designed studies are warranted to further confirm these findings.

Same-day versus staged revascularization of bilateral moyamoya arteriopathy in pediatric patients

PURPOSE

To compare the outcomes of conducting left and right hemisphere surgical revascularization on the same day versus different days for bilateral pediatric moyamoya arteriopathy patients.

METHODS

We retrospectively analyzed mortality, stroke, and transient neurologic event (TNE) rates in North American bilateral pediatric moyamoya arteriopathy patients who underwent bilateral cerebral revascularization.

RESULTS

A total of 38 pediatric (≤ 18 years old) patients at our institution underwent bilateral cerebral revascularization for moyamoya arteriopathy. Of these patients, 24 (63.2%) had both operations on the same day and 14 (36.8%) had the two operations on different days. The average length of stay for patients who underwent same-day bilateral revascularization was 6.9 ± 2.0 days and the average length of stay for each operation for patients who underwent staged bilateral revascularization was 4.5 ± 1.4 days, p = 0.001. While there were 7 (14.6%) postoperative strokes in patients who had both hemispheres revascularized on the same day, 0 (0%) strokes occurred in hemispheres after they had been operated on in the staged cohort, p = 0.042. Additionally, the postoperative stroke-free survival time in the ipsilateral hemisphere and TNE-free survival time were significantly longer in patients in the staged revascularization cohort.

CONCLUSION

Same-day bilateral revascularization was associated with longer length of stay per operation, higher rate of ipsilateral stroke, and shorter postoperative TNE-free and stroke-free survival time in the revascularized hemisphere.

The Role of Dual Antiplatelet Therapy (DAPT) vs Surgery in a Case of Moyamoya Disease: A Case Report and Review of the Literature

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by non-atherosclerotic and non-inflammatory progressive narrowing of the intracranial part of the carotid artery and its proximal branches. The disease process is commonly associated with the development of weak, dilated collateral blood vessels at the base of the brain. This gives it a classic smoky appearance on cerebral angiograms and hence the name "Moyamoya" which means "puff of smoke" in Japanese. When a patient has similar vasculopathy in the setting of another disease then it is known as Moyamoya syndrome (MMS). The associated diseases are sickle cell anemia, neurofibromatosis, long-standing diabetes, uncontrolled hypertension, or chemotherapy. Despite being known as a disease of the East Asian population, the disease is no longer exclusive to Asians, as evidenced by the rising incidence among non-Asian groups such as Caucasians, Hispanics, and African Americans. Patients can remain asymptomatic or present with ischemic or hemorrhagic stroke, headache, seizures, or recurrent transient ischemic attacks. Conventional cerebral angiography is considered the gold standard for diagnosing MMD. Treatment may be supportive, medical, or surgical. We present the case of a 42-year-old African American woman with several comorbidities who presented with sudden onset of ischemic stroke and upon further workup was found to have MMD. Equally important is to identify the most effective therapeutic approaches based on individual patients to achieve better clinical outcomes. Our case report highlights the importance of surgery in symptomatic MMD with a lack of supporting evidence indicating the benefits of dual antiplatelet therapy (DAPT).

Risk factors for wound healing complications after revascularization for MMD with complete Y-shaped incision

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease that can be treated with revascularization. Surgery increases the risk of poor wound healing (PWH) due to the impact on the blood supply to the flap. We aimed to analyze risk factors for PWH in MMD with a complete Y-shaped incision. A total of 125 patients with MMD were enrolled in this prospective observational study. The wounds were assessed and measured on the third and seventh days after surgery. The mean age of these patients was 43.3 ± 10.0 years. The ratio of male to female was 1:1.3. 15 (12.0%) patients had incision complications. 5 patients (4.0%) had redness; 2 patients (1.6%) had swelling; 2 patients (1.6%) had fat necrosis; 3 patients (2.4%) had incision infection; and 3 patients (2.4%) had flap necrosis. Student's t test showed significant differences in BMI (P = 0.040) and fever time (P = 0.050). The standard chi-squared test showed significant differences in incision infection (P = 0.010), suture mode (P = 0.047), and cutting off large branch vessels in the flap (P < 0.001). Multivariate logistic regression analysis suggested that incision infection (P = 0.026, OR 12.958), using a skin stapler (P = 0.030, OR 4.335), cutting off large branch vessels in the flap (P = 0.009, OR 5.227), and BMI (P = 0.027, OR 1.204) were risk factors. The area under the curve for risk factors for PWH on a receiver operating characteristic curve was 0.853. Incision infection, using a skin stapler, higher BMI, and cutting off large branch vessels in the flap are risk factors for PWH.

Postoperative cerebral infarction after revascularization in patients with moyamoya disease: Incidence and risk factors

OBJECTIVES

Cerebral infarction is the major complication of revascularization surgery in patients with moyamoya disease (MMD), and we analyzed the possible causes of cerebral infarction after revascularization surgery for MMD.

METHODS

MMD patients who were admitted and underwent surgical revascularization at Shanghai Huashan Hospital from January 2019 to December 2021 were retrospectively analyzed.

RESULTS

A total of 815 patients and 890 revascularization surgeries (677 first revascularization surgeries and 213 second revascularization surgeries) were included in this study; 453 (50.9%) were performed on the left side and 437 (49.1%) on the right side, with 779 (87.5%) combined procedures and 111 (12.5%) indirect bypasses included. The mean patient age at the time of these procedures was 44.6 ± 11.7 years (range 6-72 years). Postoperative cerebral infarctions were observed in 46 (5.17%) surgeries, among which 31 occurred after left hemisphere revascularization surgeries, with an incidence of 6.84%, and 15 occurred after right hemisphere revascularization surgeries, with an incidence of 3.43%. Of these, 30 (65.2%) occurred in the operated hemispheres, 2 (4.3%) in the contralateral hemisphere and 13 (28.3%) in the bilateral hemisphere. There were 11 cases of massive infarction (23.9%). The incidence of postoperative infarction in patients undergoing the first revascularization was 6% (41/677) and 2.3% (5/213) in the second revascularization surgeries. Initial presentation as infarction (P < 0.001), initial presentation as hemorrhage (P < 0.001), hypertension (P = 0.018), diabetes (P = 0.006), 1st or 2nd surgery and surgical side (P = 0.007) were found to be related to postoperative cerebral infarction. Initial presentation as infarction (OR = 2.934, 95% CI 1.453-5.928, P = 0.003), initial presentation as hemorrhage (OR = 0.149, 95% CI 0.035-0.641, P = 0.011), and 1st or 2nd surgery and surgical side (OR = 1.66, 95% CI 1.106-2.491, P = 0.014) were independently associated with cerebral infarction after revascularization surgeries.

CONCLUSIONS

In patients with MMD undergoing surgical revascularization, initial presentation as infarction and first revascularization surgery performed on the left hemisphere are independent risk factors for postoperative cerebral infarction, whereas initial presentation as hemorrhage is a protective factor.

Endothelial Cell-Derived Let-7c-Induced TLR7 Activation on Smooth Muscle Cell Mediate Vascular Wall Remodeling in Moyamoya Disease

Moyamoya disease (MMD) is characterized by frequent migration and phenotypic transformation of vascular smooth muscle cells (VSMCs) in the intima layer of blood vessels. However, the underlying mechanism is unclear. Toll-like receptor (TLR) 7 is abundantly expressed in smooth muscle cells (SMCs) in multiple vascular diseases, which might be linked to the disease-associated vascular remodeling. In the present study, the expression of TLR7 in MMD vessels was examined using the superficial temporal artery (STA) and middle cerebral artery (MCA) from MMD patients. Furthermore, the effect of TLR7 activation on the VSMC phenotype switch in vitro and vascular remodeling in vivo was assessed using a 9.4Tesla MRI. Our results demonstrated that the TLR7 and microRNA Let-7c expression are upregulated in VSMCs and the plasma of MMD patients, respectively. Additionally, TLR7 stimulation by Let-7c or Imiquimod induces a synthetic phenotype switch in VSMCs. Mechanistic studies revealed that Akt/mTOR signaling is responsible for this TLR-induced VSMC phenotypic switch. The Let-7c or Imiquimod treatment also resulted in reduced blood flow of internal carotid arteries (ICAs) in an in vivo model, while TLR7 inhibition attenuated the ICA stenosis. Besides, Let-7c was also found to be elevated in the hypoxic endothelial cells. Taken together, our study demonstrates that Let-7c released by endothelial cells under hypoxic conditions may activate TLR7 on VSMCs, ultimately leading to the phenotype switch and vascular wall remodeling. These findings thus elucidate the putative mechanisms underlying progressive stenosis of blood vessels in MMD and provide prospective therapeutic targets for further exploration.

Influence of Autologous Bone Marrow Stem Cell Therapy on the Levels of Inflammatory Factors and Conexin43 of Patients with Moyamoya Disease

Moyamoya disease is a medical condition that shows the typical characteristics like continuous and chronic thickening of the walls and the contraction of the internal carotid artery; as a result, the internal diameter of the artery gets narrowed. There are six phases of the disease ranging from I to VI (moyamoya vessels completely disappear, followed by the complete blockage of the arteries). Surgery is a commonly recommended treatment for the moyamoya disease. Our research study identifies the effect of autologous bone marrow stem cell therapy (ABMSCT) on the levels of inflammatory factors and Conexin43 (Cx43) protein in patients suffering from moyamoya. In our study, we have selected 52 moyamoya patients admitted to our hospital from 30 July 2019 to 10 February 2020. The control group (CG) was treated with superficial temporal artery to a middle cerebral artery (STA-MCA) bypass + encephalo-duro-myosinangiosis (EDMS). The experimental group (Exp. Grp) was treated with ABMSC. The cerebral vascular tissue of the patients was treated with hematoxylin-eosin (HE) staining. Immunohistochemical staining was used to identify the levels of Cx43 protein. The concentrations of vascular endothelial growth factor (VEGF), inflammatory factor interleukin-6 (IL6), interleukin-1β (IL1β), tumor necrosis factor (TNFα), and anti-inflammatory factor interleukin-1β (IL1β) were determined by enzyme-linked immunosorbent assay (ELISA). We have found that after treatment of the expression of Cx43 protein, the proportions of grade IV (7.7%), grade III (311.5%), and grade II (3.8%) patients in the Exp. Grp were lower than those in the CG. The proportion of grade I patients in the Exp. Grp (77%) was higher than that in the CG (38.5%). After treatment, the inflammatory factors IL6 (0.97 ± 0.82 pg/mL), IL1β (8.33 ± 1.21 pg/mL), and TNFα (1.73 ± 0.71 pg/mL) in the Exp. Grp were lower than those in the CG. The anti-inflammatory factor IL1β (15.09 ± 4.72 pg/mL) increased in the Exp. Grp compared with the CG (11.25 ± 3.48 pg/mL) post treatment. Intracranial infection, hydrocephalus, hemiplegia, and transient neurological dysfunction in the Exp. Grp were lower than those in the CG, with statistical differences (P < 0.05). Our study suggests that the treatment of autologous bone marrow stem cells (ABMSC) was beneficial to balance the inflammatory response of disorders, reduce the damage of vascular tissue in the brain, and regulate tissue repair by co-acting with various inflammatory factors as compared to traditional surgery. We conclude that the involvement of Cx43 in the occurrence and development of moyamoya. We also have found that the risk factors of intracranial infection after ABMSCT were less as compared to those after conventional surgery.

Surgical techniques and indications for treatment of adult moyamoya disease

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular disease involving the occlusion or stenosis of the terminal portion of the internal carotid artery (ICA) and the proximal anterior and middle cerebral arteries. Adults with MMD have been shown to progressively accumulate neurological and cognitive deficits without treatment, with a mortality rate double that of pediatric patients with MMD. Surgical intervention is the mainstay of treatment to prevent disease progression and improve clinical outcomes. Several different types of bypasses can be utilized for revascularization in MMD, including indirect, direct, and combined forms of extracranial-to-intracranial (EC-IC) bypass. Overall, the choice of appropriate technique requires consideration of the age of the patient, preoperative hemodynamics, neurologic status, and territories most at risk and in need of revascularization. Here, we will review the indications and surgical techniques for the treatment of adult MMD. Step-by-step instructions for performing several bypass variants with technical pearls are discussed.

Moyamoya syndrome with ruptured aneurysm in α‑thalassemia: A case report

Moyamoya syndrome (MMS) refers to the moyamoya vascular disease associated with various systemic diseases and conditions, including sickle cell anemia, Fanconi anemia and iron deficiency anemia. However, the association between MMS and other hemoglobinopathies is less frequently observed. MMS, like moyamoya disease, is a cerebrovascular condition that is characterized by chronic progressive stenosis or occlusion at the ends of the bilateral internal carotid arteries, anterior cerebral arteries and the beginning of the middle cerebral arteries, and is secondary to the formation of an abnormal vascular network at the base of the skull. Patients with MMS are prone to thrombosis, aneurysm and bleeding. The present study reports the case of a 43-year-old man with α-thalassemia who presented with moyamoya vessels with a ruptured aneurysm bleeding into the ventricle. α-thalassemia is considered as an extremely rare but potential cause of MMS. Since MMS is a progressive disease, early diagnosis and treatment is vital to prevent the disease from worsening.

Vessel Wall Magnetic Resonance Imaging in Cerebrovascular Diseases

Cerebrovascular diseases are a leading cause of disability and death worldwide. The definition of stroke etiology is mandatory to predict outcome and guide therapeutic decisions. The diagnosis of pathological processes involving intracranial arteries is especially challenging, and the visualization of intracranial arteries’ vessel walls is not possible with routine imaging techniques. Vessel wall magnetic resonance imaging (VW-MRI) uses high-resolution, multiparametric MRI sequences to directly visualize intracranial arteries walls and their pathological alterations, allowing a better characterization of their pathology. VW-MRI demonstrated a wide range of clinical applications in acute cerebrovascular disease. Above all, it can be of great utility in the differential diagnosis of atherosclerotic and non-atherosclerotic intracranial vasculopathies. Additionally, it can be useful in the risk stratification of intracranial atherosclerotic lesions and to assess the risk of rupture of intracranial aneurysms. Recent advances in MRI technology made it more available, but larger studies are still needed to maximize its use in daily clinical practice.

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.

Skull shape abnormalities in ischemic cerebrovascular and mental diseases in adults

Morphological changes in the child skull due to mechanical and metabolic stimulation and synostosis of the suture are well known. On the other hand, few studies have focused on clinical conditions relevant for adult skull deformity. We retrospectively reviewed computed tomography (CT) findings obtained from 365 cases that were treated for head injuries, moyamoya disease, cervical internal carotid artery stenosis, and mental diseases, and investigated the morphological changes in the skull associated with these diseases. The findings from head injuries were used not only for control subjects, but also for the analysis of generational changes in skull shape based on birth year. Head shape had a brachiocephalic tendency with occipital flattening in people born from the 1950s onwards. Cases of moyamoya disease, cervical internal carotid artery stenosis, and mental diseases showed significantly thicker frontal and occipital bone than those of control subjects. The skull thickening was especially noticeable in the frontal bone in moyamoya disease. Plagiocephaly was significantly frequent in moyamoya disease. These uncommon skull shapes are useful CT findings in screening subjects for early evidence of mental diseases and intracranial ischemic diseases with arterial stenosis.