Clinical features and endovascular treatment of ruptured peripheral cerebral aneurysms associated with moyamoya disease: an 8-year single-center experience

OBJECTIVE

Ruptured peripheral cerebral aneurysm (PPCA) associated with moyamoya disease (MMD) is rarely reported, and its optimal treatment remains controversial. This study aims to present the clinical characteristics, treatment strategies, and outcome predictors of this rare clinical entity.

METHODS

A retrospective review of patients with hemorrhagic MMD from January 2013 to December 2020 was performed. All medical records were independently compiled and reviewed.

RESULTS

Twenty-three patients were identified, 56.5% of whom were female. The mean age was 45.9 years with a peak age of onset of 51-60 years. Most patients (65.2%) developed intraventricular hemorrhage with or without intracerebral hemorrhage. These aneurysms were frequently located on the anterior (26.1%) and posterior (43.5%) choroidal arteries. Sixteen (69.6%) aneurysms were embolized and the remaining 7 (30.4%) were managed conservatively due to approach inaccessibility. Good outcomes were achieved in 82.6% of all cases, with 81.3% for embolization and 85.7% for observation. Complete occlusion was observed in all 16 aneurysms embolized. Of the conservatively treated aneurysms, 1 (14.3%) re-ruptured, 1 (14.3%) decreased in size, 2 (28.6%) disappeared, and 3 (42.8%) remained stable in size. Aneurysm rebleeding was associated with an unfavorable outcome (P = 0.026).

CONCLUSIONS

PPCA should be considered in the differential diagnosis of hemorrhagic MMD. Aneurysm rebleeding appears to be a potential predictor of poor outcome and therefore aggressive intervention should be advocated. Endovascular embolization may be safe and feasible, and conservative observation should be carefully chosen given the high risk of aneurysm re-rupture.

RNF213 Variant and Infectious Burden Associated With Intracranial Artery Stenosis in Moyamoya Disease

BACKGROUND

The mechanisms driving the progression of moyamoya disease (MMD) remain unrecognized. There is evidence suggesting that genetic and environmental factors may be associated with intracranial artery stenosis. Here, we aimed to investigate the characteristics of infectious exposure and the association of the RNF213 (RING finger protein 213) variant and infectious burden (IB) with intracranial artery stenosis of MMD.

METHODS AND RESULTS

We prospectively recruited 275 patients with MMD. Participants underwent RNF213p.R4810K sequencing. Serum antibody titers of herpes simplex virus, cytomegalovirus, toxoplasma, rubella virus, and Epstein-Barr virus were assessed and combined into an IB score. The degree of intracranial artery stenosis was measured by using the Willis narrowing score (WNS), which was then dichotomized as mild and severe. Multivariate regression analyses were performed to analyze variables associated with severe WNS. Patients with the RNF213 variant had a higher risk of severe WNS than wild-type individuals (P=0.003). Patients with MMD with severe WNS showed an increased level of IB score (P<0.001). The RNF213 variant (odds ratio [OR], 2.832 [95% CI, 1.347-5.955]; P=0.006) and IB score (OR, 1.771 [95% CI, 1.286-2.439]; P<0.001) were significantly associated with severe WNS after adjusting for covariates. Furthermore, the associations between IB score and severe WNS were more prominent among patients with modifiable risk factors of elevated body mass index (Pinteraction<0.001), triglycerides (Pinteraction=0.011), and homocysteine (Pinteraction=0.016).

CONCLUSIONS

This study outlined a perspective of the genetic-environmental interactions in the progression of MMD. The RNF213 variant and increased IB were associated with intracranial artery stenosis in MMD. The study will provide novel insights into the mechanism of disease progression, which may offer opportunities for early intervention of infectious exposure in MMD.

Impact of Revascularization Timing on Clinical Outcomes of Symptomatic Moyamoya Disease: A Systematic Review and Multivariate Analysis

BACKGROUND AND OBJECTIVES

Despite a substantial body of literature describing the efficacy of revascularization compared with conventional management of moyamoya disease (MMD), the impact of the timing of revascularization relative to stroke onset remains inadequately characterized. The aim of this review was to synthesize existing research to guide clinicians in the optimal timing of revascularization in symptomatic MMD.

METHODS

A comprehensive literature review was performed to identify studies reporting on timing of revascularization. Studies were divided into revascularization within 3 months of stroke, between 3 and 6 months of stroke, or >6 months from stroke event.

RESULTS

A total of 3049 cases and 3151 treated cerebral hemispheres were included. There were 91 individuals (2.98%) in the 3 months to intervention cohort, 152 (4.92%) individuals in the 3 to 6 months to the intervention cohort, and 2806 (92.0%) individuals in the >6 months to the intervention cohort. The average follow-up time was 43.8 ± 35.19 months. Clinical improvement was reported in 83.4% of cases overall. The 3-to-6-month poststroke preoperative interval has the highest frequency of clinical improvement (90.2%), followed by the >6-month preoperative interval (83.4%). The preoperative interval of <3 months had the lowest frequency of clinical improvement (76.5%). Comparison of average treatment effect in the treated demonstrated reduced frequency of improved clinical outcome (Mean difference: -22.6, SE: 9.15, P = .013) and increased frequency of worse clinical outcome (Mean difference: 20.1, SE: 7.38, P = .006) in the <3 months cohort. The >6 months cohort was found to be associated with a reduced frequency of worse clinical outcome (Mean difference -1.81, SE: 0.349, P = .001).

CONCLUSION

The findings of this meta-analysis suggest that, in cases where it is clinically feasible to delay revascularization following an acute neurological event in patients with MMD, postponing intervention is warranted.

Inhalational versus intravenous anesthetic for cerebrovascular accident outcomes after surgical revascularization for adult moyamoya disease

PURPOSE

To compare the effects of inhalational anesthetics and intravenous anesthetics on the neurological function of patients with moyamoya disease (MMD) after vascular bypass surgery.

METHODS

The clinical anesthesia data of patients were retrospectively collected. Patients who underwent bypass grafts with general anesthesia from January 1st, 2019, to December 31st, 2020, in Huashan Hospital affiliated with Fudan University, were selected. The primary endpoint was stroke incidence within seven days after anesthesia, and the secondary endpoints included transient neurological deficits (TNDs) and incidence of postoperative Epilepsy.

RESULTS

We compared the data of MMD patients who received inhalational anesthetics (Sevoflurane anesthetics, n = 197, group S) and intravenous anesthetics (Propofol anesthetics, n = 219, group P). The stroke incidence in the two groups (group S vs. group P) was 6.6% vs. 5.9% (OR = 0.893; 95% CI, 0.404-1.976; p = 0.780), and the group S vs. group P of TNDs incidence was 32.5% vs. 31.1% (OR = 0.936; 95% CI, 0.619-0.1.415, p = 0.753). At discharge, anesthetics didn't affect the neurological endpoint. Intravenous anesthetics provided patients with better hemodynamics compared with inhalational anesthetics during MMD vascular bypass surgery (group S vs. group P, ARVSBP: 6.4 vs. 5.2, p < 0.001, ARVDBP: 3.9 vs. 3.3, p = 0.002, ARVMBP: 4.5 vs. 3.8, p = 0.001,). There were statistical no differences in the NHISS score (S group vs. P group = 2:1, p = 0.082) at 7 days after surgery, but mRS score (S group vs. P group = 2:1, p < 0.001) at 7 days after surgery, as well as the mRS score at 6 months of follow-up (S group vs. P group = 0:0, p < 0.001), although the difference in scores was small.

CONCLUSION

Our data indicated that both inhalational and intravenous anesthetics had protective effects on patients who underwent MMD bypass grafts. MMD patients who received inhalational anesthetics and intravenous anesthetics had similar odds of neurological deficits. When comparing long-term clinical data, most patients experience good neurological recovery after receiving inhalation or intravenous anesthesia, when compared p75 mRS score(S group vs. P group = 3:1)in 6 month indicate that intravenous anesthetics might be more suitable for patients undergoing MMD bypass grafts. During the operation hemodynamic stability in the propofol group is greater than that in the sevoflurane anesthesia group.

Taurine levels and long-term adverse cerebrovascular risk in moyamoya disease: A prognostic perspective study

BACKGROUND

Taurine has been proven to play a significant role in cardiovascular and cerebrovascular diseases, but its relationship with moyamoya disease (MMD) remains unclear. This study aims to investigate the association between serum taurine levels and long-term adverse cerebrovascular events in patients with MMD after revascularization.

METHODS

This study involved 352 patients with MMD, from whom comprehensive clinical data and blood samples were collected. Serum taurine levels were measured using liquid chromatography-tandem mass spectrometry, and the relationship between serum taurine concentration and various blood indices was evaluated. Cerebrovascular adverse events included transient ischemic attack, ischemic stroke, and hemorrhagic stroke. Taurine, analyzed as a continuous variable, was found to predict a cut-off for postoperative cerebrovascular adverse events in MMD patients at 842.52 μmol/L. The impact of serum taurine levels on the risk of cerebrovascular events was analyzed using Kaplan-Meier (KM) curves, and univariate and multivariate Cox regression analyses were performed to identify predictive factors for postoperative prognosis.

RESULTS

Grouping MMD patients by serum taurine levels revealed that higher taurine levels were significantly associated with a lower proportion of hemorrhagic MMD (p = 0.044). Compared with ischemic MMD, patients with hemorrhagic MMD had lower taurine concentrations (p = 0.005). KM curves showed that the incidence of postoperative cerebrovascular adverse events in the high taurine group was significantly lower than in the low taurine group (p = 0.026). Univariate Cox regression analysis indicated that higher taurine concentrations significantly reduced the risk of postoperative cerebrovascular adverse events (Hazard Ratio [HR] = 0.334, 95 % Confidence Interval [CI] = 0.121-0.923, p = 0.035). Furthermore, the multivariate Cox regression model confirmed that taurine level is an independent predictor of long-term adverse cerebrovascular events, with the high concentration group showing a significantly reduced risk.

CONCLUSIONS

Low serum taurine levels are associated with a higher risk of long-term adverse cerebrovascular events following MMD revascularization. This suggests the significant potential of serum taurine as a prognostic biomarker for postoperative outcomes.

CLINICAL TRIAL REGISTRY NUMBER

URL: https://www.chictr.org.cn/. Unique identifier: ChiCTR2200061889.

Multi-parameter MRI-Based Machine Learning Model to Evaluate the Efficacy of STA-MCA Bypass Surgery for Moyamoya Disease: A Pilot Study

Superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery represents the primary treatment for Moyamoya disease (MMD), with its efficacy contingent upon collateral vessel development. This study aimed to develop and validate a machine learning (ML) model for the non-invasive assessment of STA-MCA bypass surgery efficacy in MMD. This study enrolled 118 MMD patients undergoing STA-MCA bypass surgery. Clinical features were screened to construct a clinical model. MRI features were extracted from the middle cerebral artery supply area using 3D Slicer and employed to build five ML models using logistic regression algorithm. The combined model was developed by integrating the radiomics score (Rad-score) with the clinical features. Model performance validation was conducted using ROC curves. Platelet count (PLT) was identified as a significant clinical feature for constructing the clinical model. A total of 3404 features (851 × 4) were extracted, and 15 optimal features were selected from each MRI sequence as predictive factors. Multivariable logistic regression identified PLT and Rad-score as independent parameters used for constructing the combined model. In the testing set, the AUC of the T1WI ML model [0.84 (95% CI, 0.70-0.97)] was higher than that of the clinical model [0.66 (95% CI, 0.46-0.86)] and the combined model [0.80 (95% CI, 0.66-0.95)]. The T1WI ML model can be used to assess the postoperative efficacy of STA-MCA bypass surgery for MMD.

Serum Creatine Levels as a Predictive Factor for Postoperative Cerebrovascular Events in Patients With Moyamoya Disease

BACKGROUND

Creatine is essential for energy storage and transfer within and outside cells. However, its relationship with cerebrovascular disease has not been fully explored. This study examined the association between serum creatine levels and postoperative cerebrovascular events, including transient ischemic attack (TIA), ischemic stroke, and hemorrhagic stroke, in patients with moyamoya disease (MMD).

METHODS

Serum creatine and disodium creatine phosphate levels were quantified in 352 patients with MMD using liquid chromatography-tandem mass spectrometry. Kaplan-Meier (KM) curves were used to analyze the impact of serum creatine levels on cerebrovascular event risk, whereas univariate and multivariate Cox regression analyses were used to identify predictors of postoperative outcomes. A prognostic nomogram was developed to predict stroke-free survival at 12, 24, and 36 months postoperatively.

RESULTS

In patients with MMD, serum creatine showed a negative correlation with creatinine (r = -0.22; p < 0.001) and homocysteine (r = -0.10; p < 0.05) but not with disodium creatine phosphate (r = -0.08; p = 0.15). When patients were divided into high and low groups based on the median serum creatine concentration, KM curve analysis revealed that patients in the high concentration group had a lower relative risk of cerebrovascular events than those in the low concentration group (hazard ratio: 0.55; 95% confidence interval, 0.33-0.94; p = 0.026). Furthermore, when patients were categorized into three levels based on creatine concentration, the overall KM curve analysis showed a significant difference (p = 0.038), such that the highest creatine concentration group (third tertile) showed a significantly reduced risk compared with the lowest concentration group (first tertile; p = 0.04).

CONCLUSION

Lower preoperative serum creatine levels were associated with a higher risk of postoperative cerebrovascular events in patients with MMD. Therefore, creatine supplementation may be an effective means of preventing adverse outcomes in patients with MMD.

Advances in moyamoya disease: pathogenesis, diagnosis, and therapeutic interventions

Moyamoya disease (MMD) is a type of cerebrovascular disease characterized by occlusion of the distal end of the internal carotid artery and the formation of collateral blood vessels. Over the past 20 years, the landscape of research on MMD has significantly transformed. In this review, we provide insights into the pathogenesis, diagnosis, and therapeutic interventions in MMD. The development of high-throughput sequencing technology has expanded our understanding of genetic susceptibility, identifying MMD-related genes beyond RNF213, such as ACTA2, DIAPH1, HLA, and others. The genetic susceptibility of MMD to its pathological mechanism was summarized and discussed. Based on the second-hit theory, the influences of inflammation, immunity, and environmental factors on MMD were also appropriately summarized. Despite these advancements, revascularization surgery remains the primary treatment for MMD largely because of the lack of effective in vivo and in vitro models. In this study, 16 imaging diagnostic methods for MMD were summarized. Regarding therapeutic intervention, the influences of drugs, endovascular procedures, and revascularization surgeries on patients with MMD were discussed. Future research on the central MMD vascular abnormalities and peripheral circulating factors will provide a more comprehensive understanding of the pathogenic mechanisms of MMD.

Research progress in unilateral moyamoya disease

Unilateral moyamoya disease (U-MMD) is a chronic vascular disease characterized by progressive stenosis and occlusion of the terminal end of the internal carotid artery and its main branches, resulting in the appearance of moyamoya-like blood vessels at the base of the brain. The etiology of U-MMD is unknown, it accounts for 9.7-17.8% of all moyamoya disease, and the family incidence is 5.5-13.3%. The clinical characteristics are similar to those of typical moyamoya disease, but there are some differences. U-MMD can progress to bilateral moyamoya disease with a median probability of 29.01% (ranging from 6.3 to 58.8%), and there are many risk factors that promote its development. Surgical treatment can effectively reduce the incidence of ischemic stroke and improve prognosis. However, the timing and indications for surgery require further investigation. This article reviews the latest research progress on the etiology, epidemiology, clinical and radiological characteristics, progression, treatment, and prognosis of U-MMD.

Reorganization of gray matter networks in patients with Moyamoya disease

Patients with Moyamoya disease (MMD) exhibit significant alterations in brain structure and function, but knowledge regarding gray matter networks is limited. The study enrolled 136 MMD patients and 99 healthy controls (HCs). Clinical characteristics and gray matter network topology were analyzed. Compared to HCs, MMD patients exhibited decreased clustering coefficient (Cp) (P = 0.006) and local efficiency (Eloc) (P = 0.013). Ischemic patients showed decreased Eloc and increased characteristic path length (Lp) compared to asymptomatic and hemorrhagic patients (P < 0.001, Bonferroni corrected). MMD patients had significant regional abnormalities, including decreased degree centrality (DC) in the left medial orbital superior frontal gyrus, left orbital inferior frontal gyrus, and right calcarine fissure and surrounding cortex (P < 0.05, FDR corrected). Increased DC was found in bilateral olfactory regions, with higher betweenness centrality (BC) in the right median cingulate, paracingulate fusiform gyrus, and left pallidum (P < 0.05, FDR corrected). Ischemic patients had lower BC in the right hippocampus compared to hemorrhagic patients, while hemorrhagic patients had decreased DC in the right triangular part of the inferior frontal gyrus compared to asymptomatic patients (P < 0.05, Bonferroni corrected). Subnetworks related to MMD and white matter hyperintensity volume were identified. There is significant reorganization of gray matter networks in patients compared to HCs, and among different types of patients. Gray matter networks can effectively detect MMD-related brain structural changes.

Intra-individual comparison of long-term outcomes between combined and indirect bypass surgery in adult moyamoya disease

PURPOSE

Bypass surgery is regarded as the standard treatment option for symptomatic and hemodynamically unstable moyamoya disease (MMD). However, there is ongoing debate about the most effective type of bypass surgery. We aimed to analyze the long-term outcomes of combined and indirect bypasses for MMD patients through intra-individual comparisons.

METHODS

Of the 896 patients who underwent 1084 bypass surgeries between 2007 and 2021, 24 patients with MMD who underwent combined bypass on one side and indirect bypass on the other side were ultimately enrolled in this study. Clinical, angiographic and hemodynamic outcomes were retrospectively evaluated.

RESULTS

Three asymptomatic strokes (12.5%) occurred within 30 postoperative days in each group. Postoperative strokes after 30 days occurred in 3 patients (12.5%) with 3 hemorrhagic events and 1 cerebral infarction, only in indirect bypass, while no stroke occurred in hemispheres treated with combined bypass. The revascularization area relative to supratentorial area was significantly greater in combined bypass than in indirect bypass, both in short-term and long-term periods (64.9% versus 43.9% in short-term and 75.7% versus 54.9% in long-term; P < .001, respectively). Hemodynamic outcomes showed significantly greater increases in acetazolamide-challenged cerebral blood flow (CBFacz) during short-term follow-up (P = .04) and in both basal CBF (CBFbas) and CBFacz during long-term follow-up (P = .014 and P = .009, respectively) in combined bypass than in indirect bypass.

CONCLUSION

Combined bypass may be a more effective treatment option for MMD based on its higher revascularization area and favorable hemodynamic results compared to indirect bypass in the same patient.

Association Between Folate Metabolism Risk, Collateral Circulation, and Hemorrhagic Risk in Moyamoya Disease

Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms are known risk factors for vascular diseases due to the impact on folate metabolism dysfunction and homocysteine (Hcy) accumulation. This study aimed to investigate the association between folate metabolism risk and hemorrhagic risk in moyamoya disease (MMD). In this prospective study, we enrolled 350 MMD patients with complete genotype data for MTHFR and MTRR. Patients were divided into non-hemorrhagic and hemorrhagic MMD groups. Folate metabolism risk was classified into three levels according to genotype configurations. We analyzed the association between folate metabolism risk and hemorrhagic risk in MMD. Furthermore, the association between folate metabolism risk, collateral circulation, and periventricular anastomosis (PA) was assessed. In vitro experiments were conducted on HBMECs to explore the potential mechanism. TT genotype and T allele in MTHFR C677T were significantly associated with a lower risk of hemorrhage, whereas AC genotype and C allele in MTHFR A1298C were significantly linked to a higher risk of hemorrhage. Patients with high folate metabolism risk exhibited a significantly decreased risk of hemorrhage compared to those with low folate metabolism risk. Further analyses demonstrated that high folate metabolism risk was significantly correlated with poor collateral circulation and PA dilation and elevated levels of Hcy. In vitro experiments showed that increased Hcy levels significantly inhibited the proliferation, migration, and tube formation of HBMECs. This study identified a significant negative correlation between folate metabolism risk and hemorrhagic risk in MMD. URL: http://www.chictr.org.cn . Unique identifier: ChiCTR2200061889.

Nomogram Based on High-Resolution Vessel Wall MRI Features to Differentiate Moyamoya Disease From Atherosclerosis-Associated Moyamoya Vasculopathy

BACKGROUND

The angiographic features of moyamoya disease (MMD) and atherosclerosis-associated moyamoya vasculopathy (AS-MMV) are similar, but the etiology and clinical treatment strategies are different. Differentiating MMD from AS-MMV helps to choose the appropriate treatment.

PURPOSE

To investigate the feasibility of a nomogram based on high-resolution vessel wall (HR-VWI) MRI features to differentiate MMD from AS-MMV.

STUDY TYPE

Retrospective.

SUBJECTS

One hundred and two patients with MMD (N = 52) or AS-MMV (N = 50) in the training cohort (9-72 years; 54 females) and 70 patients with MMD (N = 42) or AS-MMV (N = 28) in the validation cohort (7-69 years; 33 females).

FIELD STRENGTH/SEQUENCE

3-T, three-dimensional time-of-flight MR angiography (3D-TOF-MRA), spin echo high-resolution 3D T1-weighted imaging (3D-T1WI), 3D T2-weighted imaging (3D-T2WI), and contrast-enhanced 3D-T1WI.

ASSESSMENT

Image assessment was performed by three neuroradiologists (with 10, 15, and 18 years of experience). Demographic characteristic and image features were evaluated and compared. Independent factors of MMD were screened to construct a nomogram model in the training cohort. The validation cohort was used to validated its generality.

STATISTICAL TESTS

Interclass correlation coefficient (ICC), kappa, t-test, χ2 test, receiver operating characteristic (ROC) curve, area under the curve (AUC), calibration curve and concordance index (C-index). A P-value <0.05 was considered statistically significant.

RESULTS

Significant differences were observed between MMD and AS-MMV in terms of age, vessel outer diameter, vessel wall thickening pattern, maximum thickness, dot sign, and anterior cerebral artery (ACA) involved. Age, outer diameter, dot sign, and ACA involved were independent factors. The C-index was 0.886 in the training cohort and 0.859 in the validation cohort. The ROC demonstrated high diagnostic efficacy with an AUC of 0.884 in the training cohort and 0.857 in the validation cohort.

DATA CONCLUSION

A nomogram model based on age, vessel outer diameter, dot sign and ACA involved may effectively distinguish MMD from AS-MMV with good reliability and accuracy.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

Exploring RNF213 in Ischemic Stroke and Moyamoya Disease: From Cellular Models to Clinical Insights

Advances in stroke genetics have highlighted the critical role of rare genetic variants in cerebrovascular diseases, with RNF213 emerging as a key player in ischemic stroke and Moyamoya disease (MMD). Initially identified as the primary susceptibility gene for MMD, RNF213-notably the p.R4810K variant-has been strongly linked to intracranial artery stenosis (ICAS) and various ischemic stroke subtypes, particularly in East Asian populations. This gene encodes an E3 ubiquitin ligase with diverse roles in angiogenesis, vascular remodeling, lipid metabolism, and cerebral blood flow regulation, yet its exact mechanisms in cerebrovascular pathology remain incompletely understood. This review synthesizes findings from genetic studies, as well as cellular and animal models, to provide a holistic understanding of RNF213's involvement in cerebrovascular diseases. Key mechanisms by which RNF213 variants contribute to disease pathogenesis are explored, alongside discussions on their clinical utility as biomarkers and therapeutic targets. Additionally, we address the gene's implications for disease prediction, risk assessment, and cascade screening. By integrating evidence across disciplines, this review identifies critical knowledge gaps, including the biological pathways underlying RNF213's pathogenicity. These insights lay the groundwork for future research and underscore the potential of RNF213 in driving personalized approaches to cerebrovascular disease management.

Cognitive dysfunction in Moyamoya disease: latest developments and future directions

Cognitive dysfunction is common in Moyamoya disease (MMD). However, current knowledge of cognitive impairment in MMD is inadequate. In this review, we explored the characteristics of altered cognitive function associated with MMD and offered recommendations aimed at guiding potential research endeavors into the cognitive dysfunction in MMD. Cognitive functions, including executive function, intelligence, memory and so on, show characteristic declines in MMD. The effects of cerebral revascularization surgery on cognitive impairment are controversial. Currently, there is still a lack of relevant research on cognitive impairment. Research on the pathogenesis and etiology associated with Moyamoya disease as well as long-term cohort studies, are important future directions.

TdCCA with Dual-Modal Signal Fusion: Degenerated Occipital and Frontal Connectivity of Adult Moyamoya Disease for Early Identification

Cognitive impairment in patients with moyamoya disease (MMD) manifests earlier than clinical symptoms. Early identification of brain connectivity changes is essential for uncovering the pathogenesis of cognitive impairment in MMD. We proposed a temporally driven canonical correlation analysis (TdCCA) method to achieve dual-modal synchronous information fusion from electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS) for exploring the differences in brain connectivity between MMD and normal control groups. The dual-modal fusion features were extracted based on the imaginary part of coherence of the EEG signal (EEG iCOH) and the Pearson correlation coefficients of the fNIRS signal (fNIRS COR) in the resting and working memory state. The machine learning model showed that the accuracy of TdCCA method reached 97%, far higher than single-modal features and feature-level fusion CCA method. Brain connectivity analysis revealed a significant reduction in the strength of the connections between the right occipital lobe and frontal lobes (EEG iOCH: p = 0.022, fNIRS COR p = 0.011) in MMD. These differences reflected the impaired transient memory and executive function in MMD patients. This study contributes to the understanding of the neurophysiological nature of cognitive impairment in MMD and provides a potential adjuvant early identification method for individuals with chronic cerebral ischemia.

Role of scalp arteries in revascularization after side to side anastomosis in moyamoya disease patients

In our recent study, we introduced a novel side-to-side (S-S) bypass technique for adult moyamoya disease (MMD) patients. We aimed to validate the potential of this technique in enhancing postoperative revascularization. Patients undergoing S-S or end-to-side (E-S) bypass were enrolled, clinical data and angiography parameters were collected and compared. We included 44 E-S and 40 S-S MMD patients. There were no significant differences in basic characteristics and postoperative Matsushima grades between the two groups. However, in the S-S group, fewer patients had Matsushima grade D (0%) compared to the E-S group (11.4%, P = 0.028). The S-S group showed a greater occipital artery (OA) participation in revascularization (87.5% vs. 56.8%, P = 0.002) and higher postoperative caliber change ratio (CCR) of the superficial temporal artery (STA)-frontal branch (1.26 ± 0.43 vs. 1.04 ± 0.53, P = 0.038) compared to the E-S group. This difference was more pronounced in the subgroup with poor revascularization outcomes: in the S-S group, the CCR of the STA-frontal branch and the degree of participation in revascularization were 1.163 ± 0.168 and 58.8%, respectively, while in the E-S group, they were only 0.798 ± 0.494 and 6.7%. The S-S group also had a higher OA CCR (1.133 ± 0.257) and participation (82.4%) compared to the E-S group (0.941 ± 0.216 and 37.5%, respectively). In conclusion, the S-S bypass technique effectively utilizes scalp arteries, particularly the STA-frontal branch and OA, for direct revascularization via the preserved distal STA in adult MMD patients. Scalp arteries can serve as a supplementary source of donor arteries, especially beneficial for patients with suboptimal revascularization outcomes.

Difference in Clinical Phenotype, Mutation Position, and Structural Change of RNF213 Rare Variants Between Pediatric and Adult Japanese Patients with Moyamoya Disease

It is unclear how rare RNF213 variants, other than the p.R4810K founder variant, affect the clinical phenotype or the function of RNF213 in moyamoya disease (MMD). This study included 151 Japanese patients with MMD. After performing targeted resequencing for all coding exons in RNF213, we investigated the clinical phenotype and statistically analyzed the genotype-phenotype correlation. We mapped RNF213 variants on a three-dimensional (3D) model of human RNF213 and analyzed the structural changes due to variants. The RNF213 p.R4810K homozygous variant, p.R4810K heterozygous variant, and wild type were detected in 10 (6.6%), 111 (73.5%), and 30 (19.9%) MMD patients, respectively. In addition, 15 rare variants were detected in 16 (10.6%) patients. In addition to the influence of the p.R4810K homozygous variant, the frequency of cerebral infarction at disease onset was higher in pediatric patients with other rare variants (3/6, 50.0%, P = 0.006) than in those with only the p.R4810K heterozygous variant or with no variants (2/51, 3.9%). Furthermore, on 3D modelling of RNF213, the majority of rare variants found in pediatric patients were located in the E3 module and associated with salt bridge loss, contrary to the results for adult patients. The clinical phenotype of rare RNF213 variants, mapped mutation position, and their predicted structural change differed between pediatric and adult patients with MMD. Rare RNF213 variants, in addition to the founder p.R4810K homozygous variant, can influence MMD clinical phenotypes or structural change which may contribute to the destabilization of RNF213.

Comparing Outcomes of Moyamoya Disease and Moyamoya Syndrome in a Real-World Scenario: A Cohort Study

BACKGROUND

Moyamoya disease (MMD) and moyamoya syndrome (MMS) are rare cerebrovascular conditions with unclear distinctions in clinical presentation and prognosis.

AIM

This study assessed potential differences between MMD and MMS patients using real-world data on clinical manifestations, surgical outcomes, and stroke risk factors.

METHODS

This multicenter, retrospective cohort study examined patients with MMD or MMS treated at three tertiary academic hospitals in China, with a mean follow-up of 11.2 ± 3.1 years. Clinical differences were compared between MMD and MMS, and postoperative cerebrovascular events were compared between patients who underwent surgery and those with conservative management. Primary outcomes were postoperative ischemic and hemorrhagic strokes. Risk factors were evaluated via multivariate Cox regression analysis.

RESULTS

Of the 2565 patients, 2349 had MMD and 216 had MMS. After 1:1 propensity-score matching, no significant differences were observed between these two cohorts. Surgical patients had fewer cerebrovascular events than those who received conservative treatment (HR, 0.487; 95% CI, 0.334-0.711; p < 0.001). Preadmission modified Rankin scale scores > 2 (HR, 3.139; 95% CI, 1.254-7.857; p = 0.015) and periprocedural complications (HR, 8.666; 95% CI, 3.476-21.604; p < 0.001) were independent stroke risk factors in patients with MMD. Periprocedural complications (HR, 31.807; 95% CI, 10.916-92.684; p < 0.001) increased stroke risk in patients with MMS.

CONCLUSIONS

This real-world study revealed substantial clinical overlap between MMD and MMS. Both groups derived significant benefits from surgical revascularization, suggesting distinction may not be necessary to guide surgical management decisions. Optimizing preoperative status and preventing periprocedural complications may improve outcomes in these rare cerebrovascular conditions.

TRIAL REGISTRATION

This study has been registered in the Chinese Clinical trial registry (registration number: ChiCTR2200064160).

HAPLN3 p.T34A contributes to incomplete penetrance of moyamoya disease in Chinese carrying RNF213 p.R4810K

BACKGROUND AND PURPOSE

The penetrance of the RNF213 p.R4810K, a founder mutation of moyamoya disease (MMD), is estimated to be only 1/150-1/300. However, the factors affecting its penetrance remain unclear. Therefore, our study aims to identify modifier genes associated with the incomplete penetrance of this founder mutation.

METHODS

Whole-exome sequencing (WES) was performed on 36 participants, including 22 MMD patients and 14 non-MMD controls with RNF213 p.R4810K mutation. Fisher's exact test was used to assess the presence of genetic variants that differed significantly between MMD patients and non-MMD controls. In order to exclude false-positive results, another 55 carriers were included to perform Fisher's exact test for the selected sites in the WES discovery stage. Subsequently, human brain microvascular endothelial cells were transfected with wild-type and mutant HAPLN3 for tube formation assays and western blotting to explore the impact of candidate genes on angiogenesis.

RESULTS

Analysis of variants from WES data revealed a total of 12 non-synonymous variants. Through bioinformatics analysis, the focus was on the HAPLN3 p.T34A variant with a significant p value of 0.00731 in Fisher's exact test. Validation through Sanger sequencing confirmed the presence of this variant in the WES data. In vitro experiments revealed that silencing HAPLN3 and transfecting HAPLN3 p.T34A significantly enhanced tube formation and increased the relative protein expression of vascular endothelial growth factor in endothelial cells.

CONCLUSIONS

These results suggest that HAPLN3 may function as a modifier gene of RNF213 p.R4810K, promoting the development of MMD and contributing to the incomplete penetrance of MMD founder mutations.

Exploration of the risk factor for infarction after revascularization in moyamoya disease

RESULTS

Eventually, 108 consecutive patients received 174 surgeries were enrolled, experienced new or expanded infarction occured in 13 (7.47%) surgeries, which showed higher Suzuki stage on the non-operative side, more posterior cerebral artery (PCA) involvement, and more intraoperative hypotension compared to those without infarction(p < .05). The Suzuki stage on the non-operative side had the highest area under the curve (AUC) of 0.737, with a sensitivity of 0.692 and specificity of 0.783. Combination of the three factors showed better efficiency, with an AUC of 0.762, a sensitivity of 0.692, and a specificity of 0.907.

CONCLUSIONS

Revascularization was a safe option for patients with MMD, higher Suzuki stage on the non-operative side, PCA involvement, and intraoperative hypotension might be the risk factors for new or expanded infarction after revascularization in patients with MMD.

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.

Moyamoya syndrome secondary to MELAS syndrome in a child: A case report and literature revue

Mitochondrial myopathy with lactic acidosis and stroke-like episodes is a rare mitochondrial disorder, most often revealed by symptoms and signs that typically include mitochondrial myopathy, encephalopathy with stroke-like episodes, seizures and/or dementia, and lactic acidosis. Imaging findings, although diverse, usually present characteristic features that help differentiate these disorders from vascular syndromes. We present a case of a 2-year and 4-month-old girl with recurrent ischemic strokes associated with nonterritorial cortico-subcortical foci on brain imaging, along with stenosis of the terminal portion of the internal carotid arteries associated with a neovascular network. An elevated serum lactate level was found in the biological assessment. This article provides an overview of the various neuroimaging modalities available and the advent of new imaging techniques used in these disorders. It highlights the importance of considering a diagnosis of hereditary mitochondrial disorder in the presence of recurrent atypical stroke-like episodes when neuroimaging is inconsistent with ischemic infarction and reports an exceptional association with Moyamoya syndrome.

Analysis of Optic Disc Morphology and the Peripapillary Retinal and Choroidal Thickness by the Swept Source Optical Coherence Tomography in Patients with Moyamoya Disease

INTRODUCTION

Moyamoya disease (MMD) is a chronic cerebrovascular occlusive disorder. Ocular involvement in patients with MMD has increasingly been recognized and reported in recent years. This study aimed to investigate the changes of optic disc morphology and the peripapillary retinal and choroidal thickness in patients with MMD.

METHODS

This cross-sectional study included 56 patients diagnosed with idiopathic MMD and 56 healthy controls matched by age and gender. All participants underwent swept-source optical coherence tomography to capture the optic disc morphology as well as the peripapillary retinal and choroidal thickness. Optic disc parameters, including cup area, rim area, cup volume, rim volume, cup-disc area ratio (CDR), linear CDR, and vertical CDR were measured and compared between the two groups. Additionally, the thickness of the whole peripapillary retina, retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and choroid were evaluated and analyzed across 12 clock-hour segments around the peripapillary region.

RESULTS

The rim area in MMD patients was significantly less than in controls, while the CDR in MMD patients was significantly larger than that in the control group. There was no statistically significant difference between the two groups regarding disc area, cup area, cup volume, rim volume, vertical and horizontal diameter of disc. The retinal thickness at the 7 o'clock position was significantly thinner in the MMD group compared to the control group and the temporal RNFL thickness, particularly at the 7 o'clock and 9 o'clock positions, was significantly reduced in the MMD group (p < 0.05). The GCL layer at the 7 o'clock position was thinner in the MMD group than in the control group (p < 0.05). The MMD group showed a notably reduced average choroidal thickness, particularly in the inferior-temporal region (p < 0.05). There was a correlation between peripapillary choroidal and GCL layer thickness in the MMD group, but no significant correlations were found with rim area, CDR, or RNFL.

CONCLUSIONS

In patients with MMD, there is an increase in the CDR accompanied by a decrease in the rim area. Additionally, there is thinning of the temporal RNFL, GCL, and choroidal thickness, notably in the inferotemporal quadrant of the optic disc.

Usefulness of Three-dimensional Computer Graphics for the Direct Surgery of Ruptured Aneurysms in Deep Collateral Arteries Arising after Indirect Revascularization for Moyamoya Disease: Report of Two Cases

Treating ruptured aneurysms in deep collateral arteries in moyamoya disease is difficult. Two cases of intracranial hemorrhage due to ruptured aneurysms in the deep collateral vessels after indirect revascularization for moyamoya disease were treated via direct surgery with the assistance of surgical simulation using three-dimensional computer graphics. The three-dimensional computer graphics provided detailed anatomical relationships between the aneurysm and the surrounding structures, which led to successful surgical results in both patients. Ruptured aneurysms in deep collateral vessels in moyamoya disease could be successfully treated via direct surgery with the assistance of surgical simulation through three-dimensional computer graphics.

The significance of postbypass blood flow model in side to side bypass for moyamoya disease in predicting postoperative cerebral hyperperfusion syndrome

Objective

We previously developed the use of side to side (s-s) bypass for the treatment of adult moyamoya disease (MMD) and discovered several kinds of distinct blood flow models intraoperatively, which we observed through indocyanine green-video angiography (ICG-VA). The purpose of this paper was to investigate the correlation between blood flow model (BFM) identified in s-s bypass and the incidence of postoperative cerebral hyperperfusion syndrome (CHS) among patients with MMD.

Methods

We analyzed 166 hemispheres from 153 patients diagnosed with MMD, including 118 hemispheres with s-s bypass and 48 with end to side (e-s) bypass. We categorized the enrolled patients into three pairs of comparison groups based on postoperative CHS (CHS or non-CHS) in s-s bypass, blood flow models (BFM I or BFM II) and surgical approach (s-s bypass or e-s bypass). Patients' demographics and characteristics were compared between groups.

Results

Among patients who developed CHS, the occurrence of BFM I was more frequent than that of BFM II (0.154 vs. 0.019, p = 0.029 < 0.05) and no significant differences were noted in the remaining data. In the group of blood flow models, the proportion of patients with a history of cerebral hemorrhage was higher in BFM II compared to BFM I (0.062 vs. 0.226, p = 0.009 < 0.05), and the incidence of severity of ischemia was found to be higher in BFM I than in BFM II (0.774 vs. 0.429, p = 0.011 < 0.05), while the postoperative modified Rankin Scale (mRS) score and the Matsushima grade displayed no obvious difference. In comparison with the occurrence of CHS in e-s bypass group (7/48, 0.146), s-s bypass group had no difference (11/118, 0.093; p = 0.323 > 0.05), BFM I group showed no discrepancy (10/65, 0.154, p = 0.906 > 0.05) while BFM II group was different (1/53, 0.019, p = 0.047 < 0.05).

Conclusion

The proportion of postoperative CHS occurring in BFM II during s-s bypass was lower than that in e-s bypass and BFM I. The postbypass blood flow model in s-s bypass may serve as a novel predictor for postoperative CHS.

The Management of Symptomatic Moyamoya Disease in Pediatric Patients: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

The optimal management strategy for pediatric patients with symptomatic moyamoya disease (MMD) is not well established. This systematic review and meta-analysis compares surgical vs conservative management and direct/combined bypass (DB/CB) vs indirect bypass (IB) for pediatric patients with symptomatic MMD.

METHODS

MEDLINE and PubMed were searched from inception to March 17, 2024. For analysis of surgical vs conservative treatment, the primary and secondary outcomes were follow-up ischemic stroke and intracranial hemorrhagic events, respectively. For analysis of DB/CB vs IB, the primary outcome was follow-up ischemic stroke, and secondary outcomes included follow-up transient ischemic attack, new or worsened seizures, symptomatic improvement, modified Rankin Scale score ≤2, and Matsushima grade A at the last follow-up.

RESULTS

Twenty-two included studies yielded 1091 patients, with a median follow-up duration of 35.7 months. Regarding surgical vs conservative management, 428 patients were analyzed. Surgical treatment was associated with lower odds of ischemic stroke (odds ratios [OR] = 0.33 [95% CI, 0.11-0.97], P = .04), and intracranial hemorrhagic events tended to be lower with surgery (OR = 0.25 [0.06-1.03], P = .05). Regarding DB/CB techniques vs IB, 875 patients were analyzed. The groups had similar rates of ischemic stroke (OR = 0.79 [0.31-1.97], P = .61), transient ischemic attack (OR = 1.27[0.46-3.55], P = .64), new or worsened seizures (OR = 1.05[0.3-3.65], P = .93), symptomatic improvement (OR = 2.45[0.71-8.45], P = .16), and follow-up modified Rankin Scale ≤2 (OR = 1.21 [0.16-8.85], P = .85). CB was associated with higher Matsushima grade A relative to IB (OR = 3.44 [1.32-9.97], P = .01).

CONCLUSION

Surgical revascularization yielded more favorable clinical outcomes than conservative management in this meta-analysis. Clinical outcomes were similar between DB/CB vs IB techniques. Surgical flow augmentation, either by DB/CB or IB, seems to benefit pediatric patients with symptomatic MMD.

Tyrosine Kinase Inhibitor-induced Cerebrovascular Occlusion Presenting with Moyamoya Disease-like Stenosis of the Circle of Willis

Vascular occlusive events are notable adverse effects of tyrosine kinase inhibitors (TKIs), which are promising treatments for chronic myeloid leukemia (CML). We herein report the case of a patient with CML who developed cerebrovascular occlusion of the circle of Willis during TKI treatment. Our patient did not meet the diagnostic criteria for moyamoya disease due to the insignificant development of moyamoya vessels. The lack of moyamoya vessel development may be explained by the suppression of tyrosine kinases that are responsible for angiogenesis. Cerebrovascular occlusion of the circle of Willis, without significant development of moyamoya vessels, may be an important phenotype of TKI-associated vasculopathy.

Hemorrhagic Moyamoya Angiopathy in European Patients

BACKGROUND

Moyamoya angiopathy (MMA) is an important cause of juvenile stroke but an overall rare disease among European populations compared with East Asian cohorts. Consecutively, hemorrhagic MMA is described well in East Asian cohorts, but knowledge in non-Asian patients is limited. Literature suggests that disease presentation may vary between those cohorts, also including hemorrhage frequencies. Hence, this article aims to analyze hemorrhagic MMA in European patients.

METHODS

We screened for patients of European origin with MMA from a single-center consecutive database of a German hospital specialized on MMA. Those who had a record of intracranial hemorrhage were analyzed individually regarding the type of hemorrhage and use of antiplatelet therapy before and after bleeding onset. To identify associated factors of intracranial hemorrhage, an age- and sex-matched control group was identified from the pool of patients without a history of hemorrhage. Both groups had a comparable follow-up time and were compared in terms of disease presentation, therapeutic interventions, and imaging characteristics, using both univariate tests and multivariate logistic regression analysis.

RESULTS

From a pool of 332 patients with MMA we identified 288 of European ancestry. From those, 36 had a record of intracranial hemorrhage (12.5%). Thirty-three patients presenting with 37 events were included for further analysis and case-control-comparison. Most events were intracerebral hemorrhage (n=20; 54%) and subarachnoid hemorrhage (n=11; 30%). 78% developed hemorrhage although no antiplatelet therapy was in use (n=29). Seven patients developed intracranial hemorrhage ipsilateral to prior bypass surgery (21%), while 29 of the control patients had a bypass surgery (88%; P=0.0001). There was no significant difference in terms of unilateral or bilateral disease type, history of hypertension, as well as imaging characteristics (high Suzuki stage and the presence of collateral pathways in conventional angiography, as well as ischemic defects and the presence of microbleeds on cerebral magnetic resonance imaging; P>0.05 in multivariate analysis, respectively).

CONCLUSIONS

Bypass surgery was negatively associated with the development of intracranial hemorrhage in MMA in European patients. There was no difference in terms of a history of hypertension between groups, indicating that blood pressure is not the major contributor for rupture of fragile collateral vessels. The investigated imaging characteristics were not associated to hemorrhage onset and, therefore, are not suitable as a tool of screening for patients at risk.

Efficacy of double-barrel versus single-branch superficial temporal artery-middle cerebral artery bypass in the treatment of moyamoya disease: Does double-barrel bypass offer any advantages?

BACKGROUND

To compare the effectiveness of the double-barrel and single-branch superficial temporal artery-middle cerebral artery (STA-MCA) bypass in the treatment of moyamoya disease.

METHODS

We conducted a retrospective analysis of the clinical records of patients with moyamoya disease treated with either double-barrel bypass or single-branch bypass. Preoperative and postoperative rates of intracerebral hemorrhage, cerebral infarction, epilepsy, transient neurological deficits (TNEs), and modified Rankin Scale (mRS) score were compared. Cerebral computed tomography perfusion (CTP) values of surgical side MCA were compared preoperatively, and at 1 week and 6 months postoperatively.

RESULTS

A total of 48 patients were enrolled, including 22 in the double-barrel group and 26 in the single-branch group. Between the two groups, there were no significant differences in postoperative hemorrhage, cerebral infarction, epilepsy, TNEs, mRS scores, or CTP values 6 months postoperatively. The CTP value of both groups decreased 1 week after surgery, but improved 6 months later.

CONCLUSIONS

Both STA-MCA bypass methods effectively improved cerebral blood perfusion and achieved therapeutic goals. Double-barrel bypass did not increase the risk of perioperative cerebral hemorrhage, infarctions, epilepsies, or TNEs, but it had no significant advantages over single-branch bypass. Double-barrel bypass therefore should not be prioritized over single-branch bypass when electing surgical methods for treating patients with moyamoya disease.

Moyamoya Periventricular Choroidal Collateral Registry-A Multicenter Cohort Study of Moyamoya Disease with Choroidal Anastomosis: Study Protocol

Recent cohort studies on hemorrhagic and asymptomatic moyamoya disease have revealed that choroidal anastomosis, a type of fragile periventricular collateral pathway (periventricular anastomosis) typical of the disease, is an independent predictor of hemorrhagic stroke. However, treatment strategies for less-symptomatic nonhemorrhagic patients with choroidal anastomosis remain unclear. The Moyamoya Periventricular Choroidal Collateral (P-ChoC) Registry is an ongoing multicentered observational study that will test the hypothesis that extracranial-intracranial bypass prevents de novo hemorrhagic stroke in less symptomatic, nonhemorrhagic patients with choroidal anastomosis and may thus contribute to improving the prognosis of moyamoya disease. In this study, we report the study protocol of the moyamoya P-ChoC Registry and review the literature on choroidal anastomosis as a fragile collateral pathway.

Preoperative collateralization depending on posterior components in the prediction of transient neurological events in moyamoya disease

Changes in local cerebral blood flow (CBF) are a major cause of transient neurological events (TNEs) after revascularization for moyamoya disease (MMD); however, the influence of preoperative collateral pathway development on TNEs has not yet been investigated. This study included 28 hemispheres from 28 consecutive patients with MMD who underwent surgical revascularization, including a superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, between January 2014 and March 2022. The collateralization pathways included the anterior communicating artery (AcomA) collaterals, posterior communicating artery (PcomA) collaterals, transdural collaterals, posterior pericallosal anastomosis, lenticulostriate anastomosis, thalamic anastomosis, and choroidal anastomosis. These collateral pathways were analyzed to identify predictive factors significantly associated with TNEs. TNEs were observed in 11 (39.3%) hemispheres. The development of posterior pericallosal anastomosis and choroidal anastomosis was a significant independent predictor of the occurrence of TNEs after bypass surgery for MMD (P = 0.01, OR 26.9, 95% CI 1.50-480.0; P = 0.002, OR 47.6, 95% CI 2.65-856.6). The development of choroidal and posterior pericallosal anastomosis could be reliable preoperative predictors of TNEs after bypass surgery for MMD. Our results provide useful information for future studies aimed at clarifying the mechanisms underlying TNEs.

Whole-exome sequencing reveals the genetic causes and modifiers of moyamoya syndrome

Moyamoya vasculopathy secondary to various genetic disorders is classified as moyamoya syndrome (MMS). Recent studies indicate MMS occurs due to a combination of genetic modifiers and causative mutations for the primary genetic disorders. We performed whole-exome sequencing (WES) in 13 patients with various genetic disorders who developed MMS. WES successfully revealed the genetic diagnoses of neurofibromatosis type 1 (NF-1), Down syndrome, multisystemic smooth muscle dysfunction syndrome, Noonan syndrome, and alpha thalassemia. The previously reported modifier genes, RNF213 and MRVI1, were confirmed in the NF-1 and Down syndrome cases. Further analysis revealed rare hypomorphic variants in the causative genes of the primary disorders underlying MMS, such as Alagille syndrome and Rasopathies, conferred susceptibility to MMS. Genes involved in the development of pulmonary arterial hypertension (PAH), such as ABCC8 and BMPR2, were also identified as potential modifiers. The rare variants in the MMS and PAH genes were significantly enriched in the eight Japanese patients with MMS compared with the 104 Japanese individuals from the 1000 Genomes Project. Disease genes associated with the arterial occlusive conditions represented by those of Rasopathies and PAH may provide novel diagnostic markers and future therapeutic targets for MMS as well as moyamoya disease with an unknown cause.

Decreased diffusivity along the perivascular space and cerebral hemodynamic disturbance in adult moyamoya disease

Moyamoya disease (MMD) causes cerebral arterial stenosis and hemodynamic disturbance, the latter of which may disrupt glymphatic system activity, the waste clearance system. We evaluated 46 adult patients with MMD and 33 age- and sex-matched controls using diffusivity along the perivascular space (ALPS) measured with diffusion tensor imaging (ALPS index), which may partly reflect glymphatic system activity, and multishell diffusion MRI to generate freewater maps. Twenty-three patients were also evaluated via 15O-gas positron emission tomography (PET), and all patients underwent cognitive tests. Compared to controls, patients (38.4 (13.2) years old, 35 females) had lower ALPS indices in the left and right hemispheres (1.94 (0.27) vs. 1.65 (0.25) and 1.94 (0.22) vs. 1.65 (0.19), P < 0.001). While the right ALPS index showed no correlation, the left ALPS index was correlated with parenchymal freewater (ρ = -0.47, P < 0.001); perfusion measured with PET (cerebral blood flow, ρ = 0.70, P < 0.001; mean transit time, ρ = -0.60, P = 0.003; and oxygen extraction fraction, ρ = -0.52, P = 0.003); and cognitive tests (trail making test part B for executive function; ρ = -0.37, P = 0.01). Adult patients with MMD may exhibit decreased glymphatic system activity, which is correlated with the degree of hemodynamic disturbance, increased interstitial freewater, and cognitive dysfunction, but further investigation is needed.

RNF213 variant and autophagic impairment: A pivotal link to endothelial dysfunction in moyamoya disease

Moyamoya disease (MMD) is closely associated with the Ring Finger Protein 213 (RNF213), a susceptibility gene for MMD. However, its biological function remains unclear. We aimed to elucidate the role of RNF213 in the damage incurred by human endothelial cells under oxygen-glucose deprivation (OGD). We analyzed autophagy in peripheral blood mononuclear cells (PBMCs) derived from patients carrying either RNF213 wildtype (WT) or variant (p.R4810K). Subsequently, human umbilical vein endothelial cells (HUVECs) were transfected with RNF213 WT (HUVECWT) or p.R4810K (HUVECR4810K) and exposed to OGD for 2 h. Immunoblotting was used to analyze autophagy marker proteins, and endothelial function was analyzed by tube formation assay. Autophagic vesicles were observed using transmission electron microscopy. Post-OGD exposure, we administered rapamycin and cilostazol as potential autophagy inducers. The RNF213 variant group during post-OGD exposure (vs. pre-OGD) showed autophagy inhibition, increased protein expression of SQSTM1/p62 (p < 0.0001) and LC3-II (p = 0.0039), and impaired endothelial function (p = 0.0252). HUVECR4810K during post-OGD exposure (versus pre-OGD) showed a remarkable increase in autophagic vesicles. Administration of rapamycin and cilostazol notably restored the function of HUVECR4810K and autophagy. Our findings support the pivotal role of autophagy impaired by the RNF213 variant in MMD-induced endothelial cell dysfunction.

Nomogram to Predict Good Neoangiogenesis After Indirect Revascularization Surgery in Patients with Moyamoya Disease: a Case-control Study

Indirect bypass surgery is an effective treatment for moyamoya disease (MMD), but the success of the surgery depends on the formation of spontaneous collateral vessels, which cannot be accurately predicted before surgery. Developing a prediction nomogram model for neoangiogenesis in patients after indirect revascularization surgery can aid surgeons in identifying suitable candidates for indirect revascularization surgery. This retrospective observational study enrolled patients with MMD who underwent indirect bypass surgery from a multicenter cohort between December 2010 and December 2018. Data including potential clinical and radiological predictors were obtained from hospital records. A nomogram was generated based on a multivariate logistic regression analysis identifying potential predictors of good neoangiogenesis. A total of 263 hemispheres of 241 patients (mean ± SD age 24.38 ± 15.78 years, range 1-61 years) were reviewed, including 168 (63.9%) hemispheres with good postoperative collateral formation and 95 (36.1%) with poor postoperative collateral formation. Based on multivariate analysis, a nomogram was formulated incorporating four predictors, including age at operation, abundance of ICA moyamoya vessels, onset type, and Suzuki stage. The C-index for this nomogram was 0.80. Calibration curve and decision-making analysis validated the fitness and clinical application value of this nomogram. The nomogram developed in this study exhibits high accuracy in predicting good neoangiogenesis after indirect revascularization surgery in MMD patients. This model can be very helpful for clinicians when making decisions about surgical strategies for MMD patients in clinical practice.

Exploring the Impact of Hemoglobin on Cerebral Blood Flow in Arterial Territories and Surgical Outcomes: Potential Implications for Moyamoya Disease Treatment

BACKGROUND

Changes in levels of hemoglobin would result in alterations of cerebral blood flow (CBF). However, the impact of hemoglobin on CBF in moyamoya disease (MMD) remains largely unknown. This study sought to determine whether CBF would be influenced by hemoglobin before surgical revascularization and to analyze the relationships between hemoglobin and CBF with clinical outcome after surgery in patients with MMD.

METHODS AND RESULTS

We prospectively enrolled adult patients with MMD undergoing surgical revascularization between June 2020 and December 2022. Preoperative CBF was measured in the territories of anterior, middle, and posterior cerebral arteries (ACA, MCA, and PCA, respectively) using 3-dimensional pseudo-continuous arterial spin labeling magnetic resonance imaging. Clinical outcome at 1 year after surgery was evaluated using the modified Rankin Scale. A total of 60 patients with MMD were included, with 25% (n=15) experiencing unfavorable outcomes. Patients with MMD exhibited lower CBF (ACA: P=0.007; MCA: P<0.001; PCA: P=0.014), compared with healthy controls (n=40). Hemoglobin was negatively and significantly associated with CBF (ACA: β=-0.45, P<0.001; MCA: β=-0.38, P<0.001; PCA: β=-0.54, P<0.001). CBF rather than hemoglobin was significantly related with clinical outcome (ACA: P<0.001; MCA: P<0.001; PCA: P=0.001), and CBF showed high discrimination in predicting clinical outcome (ACA: area under the curve, 0.84; MCA: area under the curve, 0.84; PCA: area under the curve, 0.80).

CONCLUSIONS

Our findings demonstrate that hemoglobin significantly influences CBF, and CBF has a high predictive value for clinical outcome in MMD. The optimal hemoglobin level before surgical revascularization should be further investigated.

System Inflammation Response Index and Serum Glucose-Potassium Ratio as Prognostic Indicators for Hemorrhagic Moyamoya Disease

BACKGROUND

Hemorrhagic moyamoya disease (HMMD) can result in poor outcomes. Serum biomarkers may play a significant role in predicting HMMD outcomes. This study retrospectively analyzed the correlation between serum biomarkers at the time of admission and outcomes for patients with HMMD.

METHODS

We evaluated 270 patients with HMMD admitted to Yijishan Hopital of Wannan Medical College between July 2017 and April 2023. The patients were categorized into 2 groups according to their modified Rankin Scale scores at 3 months after discharge. Univariate and multivariate analyses were used to identify the associations between biomarkers and clinical outcomes. Receiver operating characteristic curves were obtained to investigate the potential of the biomarkers for predicting prognosis.

RESULTS

Of the 270 patients analyzed, 96 (35.6%) had unfavorable outcomes. The potential predictors were identified using the univariate analysis. The subsequent multivariate logistic regression analysis showed that the systemic inflammatory response index (SIRI) (odds ratio 0.86, 95% confidence interval 0.75-0.98, P = 0.028] and serum glucose to potassium ratio (GPR) (odds ratio 0.53, 95% confidence interval 0.38-0.76, P < 0.001) were independent risk factors of poor outcomes. The receiver operating characteristic analysis indicated that patients with a higher SIRI (≥2.12) and GPR (≥1.75) levels were more likely to have unfavorable outcomes.

CONCLUSIONS

An elevated GPR and SIRI at admission were associated with a poor clinical outcome at the 3-month follow-up for patients with HMMD. Therefore, these biomarkers could be considered in future management decisions for these patients.

Endovascular Therapy of Ruptured Aneurysms on Moyamoya Collateral Vessels: Two Cases

Background: Using two case reports of adult women with moyamoya disease presenting with intracranial hemorrhage from ruptured aneurysms on moyamoya collateral vessels, we aim to demonstrate the potential for effective endovascular treatment navigated by CT angiography, digital subtraction angiography, and flat panel CT. Case 1 Presentation: A 45-year-old female patient with sudden onset of headache, followed by somnolency. CT scan showed a four-ventricle hematocephalus caused by a 27 × 31 × 17 mm hematoma located in the left basal ganglia. Angiography revealed a 3 mm aneurysm on hypertrophic lenticulostriate artery bridging the M1 occlusion. Selective catheterization and distal embolisation with acrylic glue was done. Case 2 Presentation: A 47-year-old woman was admitted for a sudden onset of severe headache, CT scan showed four-ventricle hematocephalus. A 4 mm aneurysm on the collateral vessel-anterior chorioidal artery bridging the closure of the terminal segment of the internal carotid artery was diagnosed as the source of bleeding. Selective catheterization and distal embolisation with acrylic glue was done. Conclusions: Selective embolisation of ruptured aneurysms on moya moya collaterals is a simple, effective, and safe procedure when relevant microcatheters are used with imaging software navigation such as 3D DSA, 3D road map and flat-panel CT.

Association between angiographic and clinical outcomes after STA-MCA bypass in adult moyamoya disease

BACKGROUND AND PURPOSE

As an angiographic outcome, postoperative collateral formation (PCF) is commonly used to evaluate the effect of STA-MCA bypass in moyamoya disease (MMD), but whether it can reliably reflect clinical outcomes is still unclear. We investigated the association between PCF and clinical outcomes in adult MMD.

METHODS

All STA-MCA bypass procedures performed from January 2013 to December 2019 were screened in this prospective cohort study. Patients who acquired presurgical and follow-up catheter angiography were included. The clinical outcomes consisted of symptom improvement and recurrent cerebrovascular events. Logistic and Cox regression and Kaplan-Meier analyses were performed to explore the association between PCF and clinical outcomes.

RESULTS

Of 165 included symptomatic hemispheres of 154 patients, 104 (63.0%) and 61 (37.0%) had good and poor PCF, respectively. The hemispheres with good PCF were younger (p = 0.004) and had a higher incidence of hemodynamic dysfunction on admission (p < 0.001) than those with poor PCF. Multivariate logistic regression analysis showed that the good PCF (odd ratio, 28.96; 95% confidence interval (CI), 9.12-91.98; p < 0.001) was associated with a higher incidence of symptom improvement. Multivariate Cox regression analysis showed that the poor PCF (hazard ratio, 3.77; 95% CI, 1.31-10.84; p = 0.014) was associated with a higher incidence of recurrent cerebrovascular events. In the hemorrhagic-onset hemispheres, good PCF group had a higher incidence of symptom improvement (p < 0.001) and a longer hemorrhage-free time (p = 0.031). In the ischemic-onset hemispheres, good PCF group also had a higher incidence of symptom improvement (p < 0.001) and a longer ischemia-free time (p = 0.028).

CONCLUSIONS

As a angiographic outcome, collateral formation is a qualified surrogate measure for clinical outcomes after STA-MCA bypass in adult MMD.

Reversible sulcal fluid-attenuated inversion recovery hyperintensity after combined bypass surgery for moyamoya disease - A "crevasse" sign

Background

Transient fluid-attenuated inversion recovery (FLAIR) hyperintensity is often observed on the operated brain surface after direct or combined bypass surgery for moyamoya disease, but its pathophysiology and clinical significance are still obscure. This study was aimed to clarify the underlying mechanism and clinical significance.

Methods

This prospective study included 106 hemispheres of 61 patients with moyamoya disease and analyzed their radiological findings before and after combined bypass surgery. This study also included 11 patients who underwent superficial temporal artery to middle cerebral artery anastomosis for occlusive carotid artery diseases as the controls. Magnetic resonance imaging examination was serially repeated, and cerebral blood flow was measured before and after surgery. Signal intensity ratio (SIR) in the cortical sulci and cortex to the adjacent white matter on FLAIR images was calculated, and the postoperative SIR changes were semi-quantitatively evaluated to assess the temporal profile of postoperative FLAIR hyperintensity.

Results

Postoperative FLAIR hyperintensity occurred within the cortical sulci on the operated hemispheres in all moyamoya patients but not in patients with occlusive carotid artery diseases. SIR values started to increase immediately after surgery, peaked at about 4-fold at 4-13 days post-surgery, then declined, and recovered to baseline values over 28 days or later. The magnitude of this phenomenon was proportional to the severity of cerebral ischemia but not to postoperative hyperperfusion.

Conclusion

Reversible sulcal FLAIR hyperintensity specifically occurs in the operated hemispheres after direct bypass surgery for moyamoya disease. This "crevasse sign" may represent the mixture of the extensive leakage of oxygen and proteins from the pial arteries into the CSF.

Exploring the transcriptomic landscape of moyamoya disease and systemic lupus erythematosus: insights into crosstalk genes and immune relationships

Background

Systemic Lupus Erythematosus (SLE) is acknowledged for its significant influence on systemic health. This study sought to explore potential crosstalk genes, pathways, and immune cells in the relationship between SLE and moyamoya disease (MMD).

Methods

We obtained data on SLE and MMD from the Gene Expression Omnibus (GEO) database. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were conducted to identify common genes. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on these shared genes. Hub genes were further selected through the least absolute shrinkage and selection operator (LASSO) regression, and a receiver operating characteristic (ROC) curve was generated based on the results of this selection. Finally, single-sample Gene Set Enrichment Analysis (ssGSEA) was utilized to assess the infiltration levels of 28 immune cells in the expression profile and their association with the identified hub genes.

Results

By intersecting the important module genes from WGCNA with the DEGs, the study highlighted CAMP, CFD, MYO1F, CTSS, DEFA3, NLRP12, MAN2B1, NMI, QPCT, KCNJ2, JAML, MPZL3, NDC80, FRAT2, THEMIS2, CCL4, FCER1A, EVI2B, CD74, HLA-DRB5, TOR4A, GAPT, CXCR1, LAG3, CD68, NCKAP1L, TMEM33, and S100P as key crosstalk genes linking SLE and MMD. GO analysis indicated that these shared genes were predominantly enriched in immune system process and immune response. LASSO analysis identified MPZL3 as the optimal shared diagnostic biomarkers for both SLE and MMD. Additionally, the analysis of immune cell infiltration revealed the significant involvement of activation of T and monocytes cells in the pathogenesis of SLE and MMD.

Conclusion

This study is pioneering in its use of bioinformatics tools to explore the close genetic relationship between MMD and SLE. The genes CAMP, CFD, MYO1F, CTSS, DEFA3, NLRP12, MAN2B1, NMI, QPCT, KCNJ2, JAML, MPZL3, NDC80, FRAT2, THEMIS2, CCL4, FCER1A, EVI2B, CD74, HLA-DRB5, TOR4A, GAPT, CXCR1, LAG3, CD68, NCKAP1L, TMEM33, and S100P have been identified as key crosstalk genes that connect MMD and SLE. Activation of T and monocytes cells-mediated immune responses are proposed to play a significant role in the association between MMD and SLE.

MRI hypoperfusion as a determinant of cognitive impairment in adults with Moyamoya angiopathy

INTRODUCTION

In Moyamoya angiopathy (MMA), mechanisms underlying cognitive impairment remain debated. We aimed to assess the association of cognitive impairment with the degree and the topography of cerebral hypoperfusion in MMA.

METHODS

A retrospective analysis of neuropsychological and perfusion MRI data from adults with MMA was performed. Ischemic and haemorrhagic lesion masks were created to account for cerebral lesions in the analysis of cerebral perfusion. Whole brain volume of hypoperfused parenchyma was outlined on perfusion maps using different Tmax thresholds from 4 to 12 s. Regional analysis produced mean Tmax values at different regions of interest. Analyses compared perfusion ratios in patients with and without cognitive impairment, with multivariable logistic regression analysis to identify predictive factors.

RESULTS

Cognitive impairment was found in 20/48 (41.7%) patients. Attention/processing speed and memory were equally impaired (24%) followed by executive domain (23%). After adjustment, especially for lesion volume, hypoperfused parenchyma volume outlined by Tmax > 4 s or Tmax > 5 s thresholds was an independent factor of cognitive impairment (OR for Tmax > 4 s = 1.06 [CI 95% 1.008-1.123]) as well as attention/processing speed (OR for Tmax > 4 s = 1.07 [CI 95% 1.003-1.133]) and executive domains (OR for Tmax > 5 s = 1.08 [CI 95% 1.004-1.158]). Regarding cognitive functions, patients with processing speed and flexibility impairment had higher frontal Tmax compared to other ROIs and to patients with normal test scores.

DISCUSSION

Cerebral hypoperfusion emerged as an independent factor of cognitive impairment in MMA particularly in attention/processing speed and executive domains, with a strong contribution of frontal areas.

CONCLUSION

Considering this association, revascularization surgery could improve cognitive impairment.

Contrast enhancement patterns associated with acute stroke in moyamoya disease using MR vessel wall imaging

BACKGROUND AND PURPOSE

High-resolution magnetic resonance imaging (HR-MRI) can provide valuable insights into the histopathological characteristics of moyamoya disease (MMD). However, the patterns of vessel wall contrast enhancement have not been well established. We aimed to identify the contrast enhancement patterns of the vessel walls associated with acute cerebral infarction using HR-MRI in MMD.

METHODS

In this retrospective study, we conducted genetic tests for Ring Finger Protein 213 (RNF 213) and performed HR-MRI on patients suspected of having MMD. We analyzed wall enhancement patterns including concentric, eccentric, or mixed enhancement types, and the occurrence of acute cerebral infarction in patients who simultaneously tested positive for RNF 213 and exhibited definite features of MMD on HR-MRI.

RESULTS

Among 306 patients who underwent RNF 213 tests for the evaluation of MMD, 56 showed positive RNF 213, and HR-MRI was performed on 32 of them. Among the patients with acute cerebral infarction, the incidence rate was significantly higher in the group with concentric wall enhancement compared to patients without acute cerebral infarction (73.3% vs. 17.0%, p < .002). Furthermore, the incidence was notably elevated, even in patients with pure concentric wall enhancement (40.0% vs. 5.9%, p = .033). The area under the curve (AUC) for the group with any concentric wall enhancement showed a significant result of .78 (95% confidence interval [CI]: .61-.95, p = .007), whereas the predictive ability for pure concentric wall enhancement did not reach significance (AUC = .67, 95% CI: .48-.86, p = .100).

CONCLUSIONS

Concentric wall enhancement was a significant predictor of acute cerebral infarction in patients with MMD.

Remote ischemic conditioning prevents ischemic cerebrovascular events in children with moyamoya disease: a randomized controlled trial

BACKGROUND

Moyamoya disease (MMD) is a significant cause of childhood stroke and transient ischemic attacks (TIAs). This study aimed to assess the safety and efficacy of remote ischemic conditioning (RIC) in children with MMD.

METHODS

In a single-center pilot study, 46 MMD patients aged 4 to 14 years, with no history of reconstructive surgery, were randomly assigned to receive either RIC or sham RIC treatment twice daily for a year. The primary outcome measured was the cumulative incidence of major adverse cerebrovascular events (MACEs). Secondary outcomes included ischemic stroke, recurrent TIA, hemorrhagic stroke, revascularization rates, and clinical improvement assessed using the patient global impression of change (PGIC) scale during follow-up. RIC-related adverse events were also recorded, and cerebral hemodynamics were evaluated using transcranial Doppler.

RESULTS

All 46 patients completed the final follow-up (23 each in the RIC and sham RIC groups). No severe adverse events associated with RIC were observed. Kaplan-Meier analysis indicated a significant reduction in MACEs frequency after RIC treatment [log-rank test (Mantel-Cox), P = 0.021]. At 3-year follow-up, two (4.35%) patients had an ischemic stroke, four (8.70%) experienced TIAs, and two (4.35%) underwent revascularization as the qualifying MACEs. The clinical improvement rate in the RIC group was higher than the sham RIC group on the PGIC scale (65.2% vs. 26.1%, P < 0.01). No statistical difference in cerebral hemodynamics post-treatment was observed.

CONCLUSIONS

RIC is a safe and effective adjunct therapy for asymptomatic children with MMD. This was largely due to the reduced incidence of ischemic cerebrovascular events.

Prevalence and characteristics of vascular cognitive impairment in a European cohort of adult patients with Moyamoya angiopathy

INTRODUCTION

Moyamoya angiopathy (MMA) is associated with a high risk of stroke, but it is also increasingly recognized as leading to cognitive impairment. The aim of this study was to determine the prevalence, nature, and severity of vascular cognitive impairment no dementia (VCIND) in adults with MMA and to identify clinical and imaging factors associated with VCIND.

METHODS

We conducted a retrospective study of consecutive adult patients with MMA followed in two tertiary hospitals (Toulouse and Paris Lariboisiere). All patients underwent neuropsychological assessment and brain magnetic resonance imaging (MRI). VCIND was defined as at least two variables of the same cognitive process with z-scores of < 2 standard deviations, regardless of the cognitive domain, that do not interfere in everyday life. Baseline demographic, clinical, and imaging data were compared between patients with and without VCIND.

RESULTS

A total of 102 patients (mean age 43 years; 65% women) were included. Thirty-four patients (33.3%) had VCIND. VCIND was mild in 20/34 (59%), moderate in 8/34 (23%), and severe in 6/34 (18%) patients. Executive function was the most widely affected (25.5%), followed by attention and processing speed (24.8%). In univariable analyses, VCIND was associated with ischemic stroke at diagnosis and the presence of ischemic lesions on MRI.

CONCLUSIONS

VCIND is highly prevalent in adults with MMA. Executive functions and processing speed are predominantly affected. These findings may guide clinicians in their evaluation of patients with MMA. Further research should assess the effect of revascularization therapies on cognitive functions.

High-resolution MRI vessel wall enhancement in moyamoya disease: risk factors and clinical outcomes

OBJECTIVES

Intracranial vessel wall enhancement (VWE) on high-resolution magnetic resonance imaging (HRMRI) is associated with the progression and poor prognosis of moyamoya disease (MMD). This study assessed potential risk factors for VWE in MMD.

METHODS

We evaluated MMD patients using HRMRI and traditional angiography examinations. The participants were divided into VWE and non-VWE groups based on HRMRI. Logistic regression was performed to compare the risk factors for VWE in MMD. The incidence of cerebrovascular events of the different subgroups according to risk factors was compared using Kaplan-Meier survival and Cox regression.

RESULTS

We included 283 MMD patients, 84 of whom had VWE on HRMRI. The VWE group had higher modified Rankin Scale scores at admission (p = 0.014) and a higher incidence of ischaemia and haemorrhage (p = 0.002) than did the non-VWE group. Risk factors for VWE included the ring finger protein 213 (RNF213) p.R4810K variant (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.08-3.76, p = 0.028), hyperhomocysteinaemia (HHcy) (OR 5.08, 95% CI 2.34-11.05, p < 0.001), and smoking history (OR 3.49, 95% CI 1.08-11.31, p = 0.037). During the follow-up of 63.9 ± 13.2 months (median 65 months), 18 recurrent stroke events occurred. Cox regression showed that VWE and the RNF213 p.R4810K variant were risk factors for stroke.

CONCLUSION

The RNF213 p.R4810K variant is strongly associated with VWE and poor prognosis in MMD. HHcy and smoking are independent risk factors for VWE.

CLINICAL RELEVANCE STATEMENT

Vessel wall enhancement in moyamoya disease is closely associated with poor prognosis, especially related to the ring finger protein 213 p.R4810K variant, hyperhomocysteinaemia, and smoking, providing crucial risk assessment information for the clinic.

KEY POINTS

• The baseline presence of vessel wall enhancement is significantly associated with poor prognosis in moyamoya disease. • The ring finger protein 213 p.R4810K variant is strongly associated with vessel wall enhancement and poor prognosis in moyamoya disease. • Hyperhomocysteinaemia and smoking are independent risk factors for vessel wall enhancement in moyamoya disease.

Imaging Assessments and Clinical Significance of Brain Frailty in Moyamoya Disease

BACKGROUND AND PURPOSE

Imaging assessment of brain frailty in ischemic stroke has been extensively studied, while the correlation between brain frailty and Moyamoya disease remains obscure. This study aimed to investigate the imaging characteristics of brain frailty and its clinical applications in Moyamoya disease.

MATERIALS AND METHODS

This study included 60 patients with Moyamoya disease (107 hemispheres). All patients were divided into stroke and nonstroke groups based on clinical symptoms and imaging findings. The modified brain frailty score was adapted to consider 4 imaging signs: white matter hyperintensity, enlargement of perivascular space, old vascular lesions, and cerebral microbleed. The relative CBF of the MCA territory was quantified using pseudocontinuous arterial-spin labeling. Surgical outcome after revascularization surgery was defined by the Matsushima grade.

RESULTS

The relative CBF of the MCA territory decreased as the modified brain frailty score and periventricular white matter hyperintensity grades increased (ρ = -0.22, P = .02; ρ = -0.27, P = .005). Clinically, the modified brain frailty score could identify patients with Moyamoya disease with stroke (OR = 2.00, P = .02). Although the modified brain frailty score showed no predictive value for surgical outcome, basal ganglia enlargement of the perivascular space had a significant correlation with the postoperative Matsushima grade (OR = 1.29, P = .03).

CONCLUSIONS

The modified brain frailty score could reflect a cerebral perfusion deficit and clinical symptoms of Moyamoya disease, and its component basal ganglia enlargement of perivascular space may be a promising marker to predict surgical outcome and thus aid future clinical decision-making.

The Potential Role of Preoperative Posterior Cerebral Artery Involvement in Predicting Postoperative Transient Neurological Deficits and Ischemic Stroke After Indirect Revascularization in Patients With Moyamoya Disease

OBJECTIVE

Transient neurological deficits (TNDs) are known to develop after direct bypass for Moyamoya disease and may be risk factors for subsequent stroke. However, the factors involved in the development of TNDs and stroke after indirect revascularization alone, including their association with subsequent stroke, remain unclear. The purpose of this study was to investigate this issue.

METHODS

The subjects of the study were 30 patients with Moyamoya disease who underwent a total of 40 indirect revascularization procedures at our institution. Clinical and radiological data were collected retrospectively. To examine factors associated with the development of postoperative TND/stroke/asymptomatic disease, the clinical characteristics of each group were statistically compared.

RESULTS

The mean age at surgery was 7 years (range 1-63). TNDs developed after surgery in 9 out of 40 patients (22.5%). Stroke in the acute postoperative period occurred in 3 patients (7.5%), all of whom experienced cerebral infarctions. Demographic data and preoperative clinical information were not different between the groups. However, posterior cerebral artery involvement on preoperative imaging was significantly associated with the development of TNDs and stroke (P = 0.006). Furthermore, postoperative stroke was associated with unfavorable outcomes (P = 0.025).

CONCLUSIONS

Posterior cerebral artery involvement is significantly associated with the occurrence of TNDs. In contrast, TNDs after indirect revascularization have little relationship with the subsequent development of stroke. TNDs usually resolve without new strokes, and a better understanding of this particular pathology could help establish an optimal treatment regimen.

Intraoperative evaluation of local cerebral hemodynamic change by laser speckle contrast imaging for predicting postoperative cerebral hyperperfusion during STA-MCA bypass in adult patients with moyamoya disease

Cerebral hyperperfusion (CHP) occurred frequently after direct superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery for moyamoya disease (MMD). We analyzed cortical microvascular density (CMD) and the change of cerebral blood flow (LΔCBF) using intraoperative laser speckle contrast imaging (LSCI) on 130 hemispheres of 95 consecutive adult patients with MMD. The demographic characteristics, cortical hemodynamic sources, bypass methods, intraoperative blood flow data, and relative CBF changes on single-photon emission computed tomography (SPECT) examination (SΔrCBF) were compared between the groups with and without CHP. The median values for CMD, LΔCBF, and SΔrCBF were significantly higher in the CHP group than in the non-CHP group (CMD 0.240 vs 0.206, P = 0.004; LΔCBF 2.285 vs 1.870, P < 0.001; SΔCBF 1.535 vs 1.260, P < 0.001). Multivariate analysis revealed that hemodynamic sources of recipient parasylvian cortical arteries from MCA (M-PSCAs), end-to-side (E-S) bypass method, CMD ≥ 0.217, and LΔCBF ≥ 1.985 were the risk factors for CHP. Intraoperative LSCI was useful for evaluating hemodynamics and predicting CHP in patients with MMD.