Moyamoya disease: diagnosis and interventions

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.

White matter hyperintensities in cholinergic pathways correlates of cognitive impairment in moyamoya disease

OBJECTIVE

To investigate the effect of cholinergic pathways damage caused by white matter hyperintensities (WMHs) on cognitive function in moyamoya disease (MMD).

METHODS

We included 62 patients with MMD from a prospectively enrolled cohort. We evaluated the burden of cholinergic pathways damage caused by WMHs using the Cholinergic Pathways Hyperintensities Scale (CHIPS). Cognitive function was evaluated with the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Cognitive impairment was determined according to the cut-off of MMSE and education. Multivariate linear and logistic regression models were used to analyze whether CHIPS was independently associated with cognition. Receiver operating characteristic curve analysis was performed to identify the ability of CHIPS in discriminating cognitive impairment and normal cognition.

RESULTS

CHIPS was associated with both MMSE and MoCA (β = - 0.601 and β = - 0.672, both p < 0.001). After correcting age, sex, education, volumes of limbic areas, and other factors, CHIPS remained to be independently associated with both MMSE and MoCA (β = - 0.388 and β = - 0.334, both p < 0.001). In the logistic regression, only CHIPS was associated with cognitive impairment (odds ratio = 1.431, 95% confidence interval = 1.103 to 1.856, p = 0.007). The optimal cut-off of CHIPS score was 10, yielding a sensitivity of 87.5% and a specificity of 78.3% in identifying MMD patients with cognitive impairment.

CONCLUSIONS

The damage of cholinergic pathways caused by WMHs plays an independent effect on cognition and CHIPS could be a useful method in identifying MMD patients likely to be cognitive impairment.

CLINICAL RELEVANCE STATEMENT

This study shows that Cholinergic Pathways Hyperintensities Scale (CHIPS) could be a simple and reliable method in identifying cognitive impairment for patients with moyamoya disease. CHIPS could be helpful in clinical practice, such as guiding treatment decisions and predicting outcome.

KEY POINTS

• Cholinergic Pathways Hyperintensities Scale was significantly associated with cognitive screening tests in patients with moyamoya disease. • Cholinergic Pathways Hyperintensities Scale plays an independent effect on cognitive impairment in patients with moyamoya disease. • Cholinergic Pathways Hyperintensities Scale shows higher accuracy than education, volumes of limbic areas, and sex in identifying cognitive impairment in moyamoya disease.

Brain and the whole-body bone imaging appearances in Menkes disease: a case report and literature review

BACKGROUND

Menkes disease (MD) is a rare, inherited, multisystemic copper metabolism disorder. Classical Menkes disease is characterized by low serum copper and ceruloplasmin concentrations, leading to multiple abnormalities in the whole-body, especially in connective tissue and central nervous system. However, serum copper and ceruloplasmin levels are not reliable diagnostic biomarkers due to the low concentrations in healthy newborns either. The featured imaging manifestations play an important role in diagnosing Menkes disease. To our knowledge, there are few reports on the systemic imaging manifestations of Menkes disease.

CASE PRESENTATION

A 4-month-old male patient presented with recurrent seizures. He had cognitive, intellectual, growth, gross motor, precision movement, and language developmental lags. The patient's hemoglobin and serum ceruloplasmin level were low. On MRI, increased intracranial vascular tortuosity, cerebral and cerebellar atrophy, white matter changes, and basal ganglia abnormalities were observed. Plain radiograph revealed wormian bones, rib flaring, metaphyseal spurring, and periosteal reactions in the long bones of the limbs. A pathogenic variant in ATP7A gene was identified in the patient, so he was confirmed the diagnosis of Menkes disease. His symptoms did not improve despite symptomatic and supportive treatment during his hospitalization. Unfortunately, the infant died 3 months after leaving hospital.

CONCLUSION

A comprehensive and intuitive understanding of the disease's imaging manifestations can help clinicians to identify the disease and avoid delays in care.

Individualised evaluation based on pathophysiology for moyamoya vasculopathy: application in surgical revascularisation

BACKGROUND

Although bypass surgery is an effective treatment for moyamoya vasculopathy (MMV), the incidence of postoperative complications is still high. This study aims to introduce a novel evaluating system based on individualised pathophysiology of MMV, and to assess its clinical significance.

METHODS

This multicentre, prospective study enrolled adult patients with MMV from Huashan Hospital, Fudan University and National Center for Neurological Disorders, China between March 2021 and February 2022. Multimodal neuroimages containing structural and functional information were used to evaluate personalised disease severity and fused to localise the surgical field, avoid invalid regions and propose alternative recipient arteries. The recipient artery was further selected intraoperatively by assessing regional haemodynamic and electrophysiological information. The preanastomosis and postanastomosis data were compared with assist with the postoperative management. Patients who received such tailored revascularisations were included in the novel group and the others were included in the traditional group. The 30-day surgical outcomes and intermediate long-term follow-up were compared.

RESULTS

Totally 375 patients (145 patients in the novel group and 230 patients in the traditional group) were included. The overall complication rate was significantly lower in the novel group (p˂0.001). In detail, both the rates of postoperative infarction (p=0.009) and hyperperfusion syndrome (p=0.010) were significantly lower. The functional outcomes trended to be more favourable in the novel group, though not significantly (p=0.260). Notably, the proportion of good functional status was higher in the novel group (p=0.009). Interestingly, the preoperative statuses of perfusion and metabolism around the bypass area were significantly correlated with the occurrence of postoperative complications (P˂0.0001).

CONCLUSIONS

This novel evaluating system helps to identify appropriate surgical field and recipient arteries during bypass surgery for MMV to achieve better haemodynamic remodelling and pathophysiological improvement, which results in more favourable clinical outcomes.

RNF213 Variants, Vasospastic Angina, and Risk of Fatal Myocardial Infarction

Importance

Vasospastic angina (VSA) is vasospasm of the coronary artery and is particularly prevalent in East Asian populations. However, the specific genetic architecture for VSA at genome-wide levels is not fully understood.

Objective

To identify genetic factors associated with VSA.

Design, Setting, and Participants

This was a case-control genome-wide association study of VSA. Data from Biobank Japan (BBJ; enrolled patients from 2002-2008 and 2013-2018) were used, and controls without coronary artery disease (CAD) were enrolled. Patients from the BBJ were genotyped using arrays or a set of arrays. Patients recruited between 2002 and 2005 were classified within the first dataset, and those recruited between 2006 and 2008 were classified within the second dataset. To replicate the genome-wide association study in the first and second datasets, VSA cases and control samples from the latest patients in the BBJ recruited between 2013 and 2018 were analyzed in a third dataset.

Exposures

Single-nucleotide variants associated with VSA.

Main Outcomes and Measures

Cases with VSA and controls without CAD.

Results

A total of 5720 cases (mean [SD] age, 67 [10] years; 3672 male [64.2%]) and 153 864 controls (mean [SD] age, 62 [15] years; 77 362 male [50.3%]) in 3 datasets were included in this study. The variants at the RNF213 locus showed the strongest association with VSA across the 3 datasets (odds ratio [OR], 2.34; 95% CI, 1.99-2.74; P = 4.4 × 10-25). Additionally, rs112735431, an Asian-specific rare deleterious variant (p.Arg4810Lys) experimentally shown to be associated with reduced angiogenesis and a well-known causal risk for Moyamoya disease was the most promising candidate for a causal variant explaining the association. The effect size of rs112735431 on VSA was distinct from that of other CADs. Furthermore, homozygous carriers of rs112735431 showed an association with VSA characterized by a large effect estimate (OR, 18.34; 95% CI, 5.15-65.22; P = 7.0 × 10-6), deviating from the additive model (OR, 4.35; 95% CI, 1.18-16.05; P = .03). Stratified analyses revealed that rs112735431 exhibited a stronger association in males (χ21 = 7.24; P = .007) and a younger age group (OR, 3.06; 95% CI, 2.24-4.19), corresponding to the epidemiologic features of VSA. In the registry, carriers without CAD of the risk allele rs112735431 had a strikingly high mortality rate due to acute myocardial infarction during the follow-up period (hazard ratio, 2.71; 95% CI, 1.57-4.65; P = 3.3 × 10-4). As previously reported, a possible overlap between VSA and Moyamoya disease was not found.

Conclusions and Relevance

Results of this study suggest that vascular cell dysfunction mediated by variants in the RNF213 locus may promote coronary vasospasm, and the presence of the risk allele could serve as a predictive factor for the prognosis.

Prediction of cerebral infarction after bypass surgery in adult moyamoya disease: using pulsatility index on TCD

BACKGROUND

At present, the most effective treatment for symptomatic moyamoya disease (MMD) is surgery. However, the high incidence of postoperative complications is a serious problem plaguing the surgical treatment of MMD, especially the acute cerebral infarction. Decreased cerebrovascular reserve is an independent risk factor for ischemic infarction, and the pulsatility index (PI) of transcranial Doppler (TCD) is a common intuitive index for evaluating intracranial vascular compliance. However, the relationship between PI and the occurrence of ischemic stroke after operation is unclear.

OBJECTIVE

To explore whether the PI in the middle cerebral artery (MCA) could serve as a potential predictor for the occurrence of ischemic infarction after bypass surgery in MMD.

METHODS

We performed a retrospective analysis of data from 71 patients who underwent combined revascularization surgery, including superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-synangiosis (EDMS). The patients were divided into two groups according to the median of ipsilateral MCA-PI before operation, low PI group (MCA-PI < 0.614) and high PI group (MCA-PI ≥ 0.614). Univariate and multivariate regression analysis were used to explore risk factors affecting the occurrence of postoperative cerebral infarction.

RESULTS

Among the 71 patients with moyamoya disease, 11 patients had cerebral infarction within one week after revascularization. Among them, 10 patients' ipsilateral MCA-PI were less than 0.614, and another one's MCA- PI is higher than 0.614. Univariate analysis showed that the lower ipsilateral MCA-PI (0.448 ± 0.109 vs. 0.637 ± 0.124; P = 0.001) and higher Suzuki stage (P = 0.025) were linked to postoperative cerebral infarction. Multivariate analysis revealed that lower ipsilateral MCA-PI was an independent risk factor for predicting postoperative cerebral infarction (adjusted OR = 14.063; 95% CI = 6.265 ~ 37.308; P = 0.009).

CONCLUSIONS

A lower PI in the ipsilateral MCA may predict the cerebral infarction after combined revascularization surgery with high specificity. And combined revascularization appears to be safer for the moyamoya patients in early stages.

Identification of oxidative phosphorylation-related genes in moyamoya disease by combining bulk RNA-sequencing analysis and machine learning

Introduction: Moyamoya disease (MMD) is a chronic cerebrovascular disease that can lead to ischemia and hemorrhagic stroke. The relationship between oxidative phosphorylation (OXPHOS) and MMD pathogenesis remains unknown. Methods: The gene expression data of 60 participants were acquired from three Gene Expression Omnibus (GEO) datasets, including 36 and 24 in the MMD and control groups. Differentially expressed genes (DEGs) between MMD patients MMD and control groups were identified. Machine learning was used to select the key OXPHOS-related genes associated with MMD from the intersection of DEGs and OXPHOS-related gene sets. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), gene set enrichment analysis (GSEA), Immune infiltration and microenvironments analysis were used to analyze the function of key genes. Machine learning selected four key OXPHOS-related genes associated with MMD: CSK, NARS2, PTPN6 and SMAD2 (PTPN6 was upregulated and the other three were downregulated). Results: Functional enrichment analysis showed that these genes were mainly enriched in the Notch signaling pathway, GAP junction, and RNA degradation, which are related to several biological processes, including angiogenesis, proliferation of vascular smooth muscle and endothelial cells, and cytoskeleton regulation. Immune analysis revealed immune infiltration and microenvironment in these MMD samples and their relationships with four key OXPHOS-related genes. APC co-inhibition (p = 0.032), HLA (p = 0.001), MHC I (p = 0.013), T cellco- inhibition (p = 0.032) and Type I IFN responses (p < 0.001) were significantly higher in the MMD groups than those in the control groups. The CSK positively correlated with APC co-inhibition and T cell-co-inhibition. The NARS2 negatively correlated with Type I IFN response. The SMAD2 negatively correlated with APC co-inhibition and Type I IFN response. The PTPN6 positively correlated with HLA, MHC I and Type I IFN responses. Discussion: This study provides a comprehensive understanding of the role of OXPHOS in MMD and will contribute to the development of new treatment methods and exploration of MMD pathogenesis.

Outcomes of Bypass Surgery in Adult Moyamoya Disease by Onset Type

Importance

Moyamoya disease (MMD) is a rare chronic cerebrovascular disease, and the outcomes of bypass management in adult patients remain controversial.

Objective

To categorize adult MMD based on asymptomatic, ischemic, and hemorrhagic onset and compare the outcomes (death, hemorrhagic stroke [HS], and ischemic stroke [IS]) of bypass surgery (direct or indirect) with those of conservative management.

Design, Setting, and Participants

This retrospective, nationwide, population-based longitudinal cohort study used Korean National Health Insurance Research data to identify adults (aged ≥15 years) with MMD who were diagnosed between January 1, 2008, and December 31, 2020, and followed up until December 31, 2021 (median follow-up, 5.74 [IQR, 2.95-9.42] years). A total of 19 700 participants (3194 with hemorrhagic, 517 with ischemic, and 15 989 with asymptomatic MMD) were included. Data were analyzed from January 2 to April 1, 2023.

Exposures

Bypass surgery and conservative management.

Main Outcomes and Measures

Death constituted the primary outcome; secondary outcomes consisted of HS or IS. Kaplan-Meier survival curve and Cox proportional hazards regression analysis were applied. The propensity score-matching and stratified analyses were performed to control covariate effects.

Results

A total of 19 700 patients (mean [SD] age, 45.43 [14.98] years; 12 766 [64.8%] female) were included. Compared with conservative management, bypass was associated with a reduced risk of death (adjusted hazard ratio [AHR], 0.50 [95% CI, 0.41-0.61]; P < .001) and HS (AHR, 0.36 [0.30-0.40]; P < .001) in hemorrhagic MMD; reduced risk of IS (AHR, 0.55 [95% CI, 0.37-0.81]; P = .002) in ischemic MMD; and reduced risk of death (AHR, 0.74 [95% CI, 0.66-0.84]; P < .001) in asymptomatic MMD. However, bypass was associated with an increased risk of HS (AHR, 1.76 [95% CI, 1.56-2.00]; P < .001) in asymptomatic MMD. Both direct and indirect bypass demonstrated similar effects in hemorrhagic and asymptomatic MMD, except only direct bypass was associated with a reduced risk of IS (AHR, 0.52 [95% CI, 0.33- 0.83]; P = .01) in ischemic MMD. After stratification, bypass was associated with a reduced risk of death in patients younger than 55 years with ischemic (AHR, 0.34 [95% CI, 0.13- 0.88]; P = .03) and asymptomatic (AHR, 0.69 [95% CI, 0.60-0.79]; P < .001) MMD, but an increased risk of HS in patients 55 years or older with ischemic MMD (AHR, 2.13 [95% CI, 1.1-4.16]; P = .03).

Conclusions and Relevance

The findings of this cohort study of bypass outcomes for patients with MMD emphasize the importance of tailoring management strategies in adult patients based on onset types.

SDF-1/CXCR4 axis participants in the pathophysiology of adult patients with moyamoya disease

BACKGROUND

Moyamoya disease (MMD) is characterized by an abundance of moyamoya vessels; however, the precise mechanism driving the spontaneous angiogenesis of these compensatory vessels remains unclear. Previous research has established a link between the stromal cell-derived factor-1 (SDF-1)/ CXC receptor 4 (CXCR4) axis and angiogenesis under hypoxic conditions. Nevertheless, the alterations in this axis within the cerebrospinal fluid, arachnoid membranes and vascular tissue of MMD patients have not been fully investigated.

METHODS

Our study enrolled 66 adult MMD patients and 61 patients with atherosclerotic vascular disease (ACVD). We investigated the SDF-1 concentration in cerebrospinal fluid (CSF) and CXCR4 expression level on the arachnoid membranes and vascular tissue. We utilized enzyme-linked immunosorbent assay and immunohistochemistr. Additionally, we cultured and stimulated human brain microvascular endothelial cells (HBMECs) and smooth muscle cells (SMCs) under oxygen and glucose deprivation (OGD) conditions followed by reoxygenation, to examine any changes in the SDF-1/CXCR4 axis.

RESULTS

The results demonstrated an elevation in the level of SDF-1 in CSF among MMD patients compared to those with ACVD. Moreover, the expression of CXCR4 in arachnoid membranes and vascular tissue showed a similar trend. Furthermore, the content of CXCR4 in HBMECs and SMCs increased with the duration of ischemia and hypoxia. However, it was observed that the expression of CXCR4 decreased at OGD/R 24h compared to OGD 24h. The temporal pattern of SDF-1 expression in HBMECs and SMCs mirrored that of CXCR4 expression.

CONCLUSION

These findings indicate a critical role for the SDF-1/CXCR4 axis in the angiogenesis of moyamoya disease.

Application of individual brain connectome in chronic ischemia: mapping symptoms before and after reperfusion

How brain functions in the distorted ischemic state before and after reperfusion is unclear. It is also uncertain whether there are any indicators within ischemic brain that could predict surgical outcomes. To alleviate these issues, we applied individual brain connectome in chronic steno-occlusive vasculopathy (CSOV) to map both ischemic symptoms and their postbypass changes. A total of 499 bypasses in 455 CSOV patients were collected and followed up for 47.8 ± 20.5 months. Using multimodal parcellation with connectivity-based and pathological distortion-independent approach, areal MR features of brain connectome were generated with three measurements of functional connectivity (FC), structural connectivity, and PageRank centrality at the single-subject level. Thirty-three machine-learning models were then trained with clinical and areal MR features to obtain acceptable classifiers for both ischemic symptoms and their postbypass changes, among which, 11 were deemed acceptable (AUC > 0.7). Notably, the FC feature-based model for long-term neurological outcomes performed very well (AUC > 0.8). Finally, a Shapley additive explanations plot was adopted to extract important individual features in acceptable models to generate "fingerprints" of brain connectome. This study not only establishes brain connectomic fingerprint databases for brain ischemia with distortion, but also provides informative insights for how brain functions before and after reperfusion.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Stroke and Disease Progression During Long-Term Follow-Up of Patients with Moyamoya Disease Older Than 50 Years

OBJECTIVE

The long-term prognosis of elderly patients with moyamoya disease (MMD) is not fully understood and needs to be elucidated.

METHODS

MMD patients who first visited our institute between 1999 and 2019, were ≥ 50 years of age, and were followed for ≥1 year were retrospectively included. Follow-up data such as stroke and disease progression on magnetic resonance angiography (MRA) were collected from medical records. The surgical outcomes of ischemic patients treated with indirect revascularization were assessed.

RESULTS

Of the 60 patients included (mean (standard deviation) = 57.0 (5.5) years, 38 females), 9 patients initially received indirect revascularization, 3 patients received direct revascularization, and 49 patients were treated conservatively. During the 57.4 (53.7) month follow-up, the symptomatic stroke rate (person-year %) was 2.79%, and MRA progression was 3.14%. Symptomatic patients had a greater rate of symptomatic stroke than asymptomatic patients did (1.46%-5.74% vs. 0.94%, P = 0.15), while MRA progression was more common in asymptomatic patients (0%-3.83% vs. 5.64%, P = 0.22). Among the 14 hemispheres of 11 patients who underwent indirect revascularization, 13/14 (92.9%) demonstrated good neovascularization and no ischemic stroke occurred after surgery.

CONCLUSIONS

In elderly patients with MMD, MRA progression was not uncommon, especially in asymptomatic patients. Symptomatic patients exhibited a high symptomatic stroke rate, and indirect revascularization seems to be effective at reducing future ischemic stroke in ischemic patients with misery perfusion. Because follow-up events were not uncommon, lifelong follow-up seems necessary for elderly MMD patients, as well as for younger patients.

Characterization of PANoptosis-related genes and the immune landscape in moyamoya disease

Moyamoya disease (MMD) is a cerebrovascular narrowing and occlusive condition characterized by progressive stenosis of the terminal portion of the internal carotid artery and the formation of an abnormal network of dilated, fragile perforators at the base of the brain. However, the role of PANoptosis, an apoptotic mechanism associated with vascular disease, has not been elucidated in MMD. In our study, a total of 40 patients' genetic data were included, and a total of 815 MMD-related differential genes were screened, including 215 upregulated genes and 600 downregulated genes. Among them, DNAJA3, ESR1, H19, KRT18 and STK3 were five key genes. These five key genes were associated with a variety of immune cells and immune factors. Moreover, GSEA (gene set enrichment analysis) and GSVA (gene set variation analysis) showed that the different expression levels of the five key genes affected multiple signaling pathways associated with MMD. In addition, they were associated with the expression of MMD-related genes. Then, based on the five key genes, a transcription factor regulatory network was constructed. In addition, targeted therapeutic drugs against MMD-related genes were obtained by the Cmap drug prediction method: MST-312, bisacodyl, indirubin, and tropanyl-3,5-dimethylbenzoate. These results suggest that the PANoptosis-related genes may contribute to the pathogenesis of MMD through multiple mechanisms.

Risk factors of rupture and mortality for intracranial aneurysms associated with moyamoya disease: a multicenter retrospective study

OBJECTIVE

The aim of this study was to analyze the risk factors for aSAH and subsequent death in patients with MMD.

METHODS

Chinese Multi-Center Cerebral Aneurysm Database (CMAD) is a multicenter study registered in China. From 2016 to 2021, 181 patients with MMD in CMAD. Logistic regression analysis was used to identify risk factors for intracranial aneurysm rupture. Univariate and multivariate Cox regression were used to risk factors associated with ruptured intracranial aneurysm patients with MMD follow-up events (death). Cumulative survival was described using the Kaplan‒Meier technique.

RESULTS

Of 11,686 IA patients, 181 (1.5%) had MMD. In the study, 158 patients with MMD were enrolled. There were 53 ruptured aneurysms and 105 unruptured aneurysms. In multivariate analysis, age (≥ 60 years OR 2.350 [1.008-5.478]), location (middle cerebral artery OR5.431 [1.347-21.889]; posterior circulation arteries OR 3.189 [1.110-9.163]) and aneurysm size (≥ 5 mm OR 2.855 [1.274-6.397], P = 0.011) were associated with intracranial aneurysm rupture in patients with MMD. In the 2-year follow-up time of aSAH patients, 44% (22/50) had favorable outcomes, 14% (7/50) had unfavorable outcomes and 42% (21/50) had death. Hypertension (HR 6.643 [1.620-27.244], P = 0.009) and Hunt-Hess grade (H&H grade IV HR 14.852 [3.151-70.011], P = 0.001; H&H grade V HR 17.697 [3.046-102.842], P = 0.001) were associated with increased mortality. In contrast, both ST (HR 0.168 [0.031-0.921], P = 0.04) and ET (HR 0.289 [0.087-0.957], P = 0.042) achieved good results.

CONCLUSIONS

This study showed that the proportion of MMD in IA patients was approximately 1.5% (181/11686). For patients with cerebral ischemia on admission, revascularization may prevent the rupture of intracranial aneurysms. Age ≥ 60 years, location, and aneurysm size ≥ 5 mm were associated with IA rupture. Further analysis showed that being located in the middle cerebral artery was the most relevant risk factor for rupture. Patients with ruptured IA who underwent ST or ET had better clinical outcomes and survival than those who underwent CT; however, hypertension and poor initial Hunt-Hess grade were independent predictors of death.

Moyamoya disease in a 2-year-old patient from the middle east: a case report and literature review

Introduction and importance

Moyamoya disease (MMD) is a condition characterized by progressive narrowing of arteries in the brain and abnormal development of small collateral vessels. It is commonly found in East Asia but has never been reported in Palestine.

Case presentation

A 2-year-old female, part of a twin born to non-consanguineous parents, presented with recurring seizures and developmental regression. The physical examination revealed signs of hypotonia, reflex abnormalities, and bilateral Babinski signs. Comprehensive laboratory tests and imaging investigations confirmed the diagnosis of MMD, marking this patient as the reported case in Palestine.

Clinical discussion

The diagnostic criteria for this condition were revised in 2021 to focus on findings seen in angiography and magnetic resonance angiography (MRA) scans. MMD has not been curative so far, and the management is focused on preventing complications, sometimes with surgical revascularization, including its different approaches: direct, indirect, and a combination of both.

Conclusion

This case highlights the importance of identifying MMD in regions where it is uncommon to be diagnosed. It emphasizes the need for diagnosis and appropriate intervention to reduce complications.

Moyamoya Disease: Advances in Diagnosis, Treatment, and Surgical Interventions

Moyamoya disease (MMD) is a rare cerebrovascular disorder characterized by progressive narrowing of the brain's arteries, leading to an increased risk of stroke. The primary susceptibility gene, RNF213, has been identified in individuals of East Asian descent, contributing to ongoing research into potential therapeutic targets. The distinction between idiopathic MMD and secondary forms, such as Moyamoya syndrome (MMS), is discussed, focusing on associated conditions and risk factors. Surgical revascularization emerges as the mainstay of treatment, with direct, indirect, and combination bypass procedures explored. The review delves into advancements in imaging technology for diagnosis and treatment planning, emphasizing non-invasive magnetic resonance examination's role in identifying asymptomatic patients. Additionally, insights into anesthetic care and therapeutic approaches underscore the evolving understanding of this complex disease. The presented information aims to contribute to the ongoing dialogue surrounding MMD, providing a valuable resource for clinicians and researchers.

White matter hyperintensities mediate the association between frailty and cognitive impairment in moyamoya disease

OBJECTIVES

The relationship between cognitive function and frailty in moyamoya disease (MMD) remains unclear, and the underlying mechanism is poorly understood. This study aims to investigate whether white matter hyperintensities (WMHs) mediate the association between frailty and cognitive impairment in MMD.

METHODS

Patients with MMD were consecutively enrolled in our study from January 2021 to May 2023. Pre-admission frailty and cognition were assessed using the Clinical Frailty Scale (CFS) and cognitive tests, respectively. Regional deep WMH (DWMH) and periventricular WMH (PWMH) volumes were calculated using the Brain Anatomical Analysis using Diffeomorphic deformation toolbox based on SPM 12 software. Multivariate logistic regression analysis was conducted to evaluate the association between frailty and cognitive function in MMD. Mediation analysis was performed to assess whether WMHs explained the association between frailty and cognition.

RESULTS

A total of 85 patients with MMD were enrolled in this study. On the basis of the CFS scores, 24 patients were classified as frail, 38 as pre-frail, and 23 as robust. Significant differences were observed in learning, memory, processing speed, executive functions, and semantic memory among the three groups (p < 0.001). Frailty was independently associated with memory and executive functions (p < 0.05); even after controlling for WMH. Mediation analysis indicated that the associations of frailty with memory and executive functions were partially mediated by WMH, DWMH, and PWMH (p < 0.05).

CONCLUSION

Frailty is significantly correlated with a higher risk of cognitive impairment in MMD, even after adjusting for other covariates. WMHs partially mediate the association between frailty and cognitive impairment.

Incidence and Outcomes of Posterior Circulation Involvement in Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a progressive, occlusive disease of the internal carotid arteries and their proximal branches, with the subsequent development of an abnormal vascular network that is rupture-prone. Steno-occlusive changes in the posterior cerebral arteries (PCAs) may contribute to worsened outcomes in patients with MMD; however, there is little information on the incidence and natural history of posterior circulation MMD (PCMMD). We describe clinical PCMMD characteristics in a large cohort of patients with MMD.

METHODS

We retrospectively reviewed patients with MMD treated between 1991 and 2019 at a large academic medical center. Demographics, perioperative outcomes, and radiological phenotypes were recorded for 770 patients. PCA disease was graded as either 0 (no disease), 1 (mild), 2 (moderate), or 3 (severe or occluded) based on cerebral angiography. Patients with angiographically confirmed MMD diagnosis with at least 6 months follow-up and completion of revascularization surgery were included; patients with intracranial atherosclerosis, intracranial dissection, vasculitis, and undefined inflammatory processes were excluded. The presence of stenosis/occlusion was graded radiographically to assess for disease progression and the prevalence of risk factors related to reduced progression-free survival.

RESULTS

In all, 686 patients met the inclusion criteria, with PCA disease identified in 282 (41.1%) patients. Of those 282 patients with PCMMD, disease severity ranged from 99 (35.1%) with mild, 72 (25.5%) with moderate, and 111 (39.4%) with severe. The total number of postoperative complications was significantly associated with PCMMD severity (P=0.0067). Additionally, PCMMD severity correlated with worse postoperative modified Rankin Scale scores (P<0.0001). At a mean follow-up of 6.0±3.9 (range, 0.1-25.0) years, a total of 60 (12.6%) patients showed new/worsening PCMMD. The overall postoperative, progression-free survival in patients with PCMMD was 95.4% at 1 year, 82.4% at 3 years, 68.8% at 5 years, and 28.3% at 10 years, with prognostic factors for progression including preoperative PCMMD status, history of tobacco use, and hypertension (P<0.0001, P<0.001, and P<0.0001, respectively).

CONCLUSIONS

PCA disease involvement in MMD is associated with higher rates of ischemic perioperative complications and worsened functional outcomes, likely due to reduced collateral flow. Ten-year progression of PCA disease is highly likely and should be monitored throughout follow-up; future studies will assess the impact of PCA disease progression on long-term outcomes.

Hemoglobin Drop is Associated with Early Post-operative Stroke Following Revascularization Surgery for Moyamoya Disease

BACKGROUND

Postoperative stroke is a potentially devastating neurological complication following surgical revascularization for Moyamoya disease. We sought to evaluate whether peri-operative hemoglobin levels were associated with the risk of early post-operative stroke following revascularization surgery in adult Moyamoya patients.

METHODS

Adult patients having revascularization surgeries for Moyamoya disease between 1999-2022 were identified through single institutional retrospective review. Logistic regression analysis was used to test for the association between hemoglobin drop and early postoperative stroke.

RESULTS

In all, 106 revascularization surgeries were included in the study. A stroke occurred within 7 days after surgery in 9.4% of cases. There were no significant associations between the occurrence of an early postoperative stroke and patient age, gender, or race. Mean postoperative hemoglobin drop was greater in patients who suffered an early postoperative stroke compared with patients who did not (2.3±1.1 g/dL vs. 1.3±1.1 g/dL, respectively; P=0.034). Patients who experienced a hemoglobin drop post-operatively had 2.03 times greater odds (95% confidence interval, 1.06-4.23; P=0.040) of having a stroke than those whose hemoglobin levels were stable. Early postoperative stroke was also associated with an increase in length of hospital stay (P<0.001), discharge to a rehabilitation facility (P=0.014), and worse modified Rankin scale at 1 month (P=0.001).

CONCLUSION

This study found a significant association between hemoglobin drop and early postoperative stroke following revascularization surgery in adult patients with Moyamoya disease. Based on our findings, it may be prudent to avoid hemoglobin drops in Moyamoya patients undergoing surgical revascularization.

Stroke in Asia

BACKGROUND

There is a significant burden of stroke in Asia. Asia has the largest population in the world in 2023, estimated at 4.7 billion. Approximately 9.5-10.6 million strokes will be anticipated annually in the backdrop of a diverse group of well-developed and less developed countries with large disparities in stroke care resources. In addition, Asian countries are in varying phases of epidemiological transition.

SUMMARY

In this review, we examined recent epidemiological features of ischaemic stroke and intracerebral haemorrhage in Asia with recent developments in hyperacute stroke reperfusion therapy and technical improvements in intracerebral haemorrhage. The article also discussed the spectrum of cerebrovascular diseases in Asia, which include intracranial atherosclerosis, intracerebral haemorrhage, infective aetiologies of stroke, moyamoya disease, vascular dissection, radiation vasculopathy, and cerebral venous thrombosis.

KEY MESSAGES

The review of selected literature and recent updates calls for attention to the different requirements for resources within Asia and highlights the breadth of cerebrovascular diseases still requiring further research and more effective therapies.

Stroke Events and Risk Factors in Older Patients with Moyamoya Disease

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

High-resolution magnetic resonance vessel wall imaging provides new insights into Moyamoya disease

Moyamoya disease (MMD) is a rare condition that affects the blood vessels of the central nervous system. This cerebrovascular disease is characterized by progressive narrowing and blockage of the internal carotid, middle cerebral, and anterior cerebral arteries, which results in the formation of a compensatory fragile vascular network. Currently, digital subtraction angiography (DSA) is considered the gold standard in diagnosing MMD. However, this diagnostic technique is invasive and may not be suitable for all patients. Hence, non-invasive imaging methods such as computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are often used. However, these methods may have less reliable diagnostic results. Therefore, High-Resolution Magnetic Resonance Vessel Wall Imaging (HR-VWI) has emerged as the most accurate method for observing and analyzing arterial wall structure. It enhances the resolution of arterial walls and enables quantitative and qualitative analysis of plaque, facilitating the identification of atherosclerotic lesions, vascular entrapment, myofibrillar dysplasia, moyamoya vasculopathy, and other related conditions. Consequently, HR-VWI provides a new and more reliable evaluation criterion for diagnosing vascular lesions in patients with Moyamoya disease.

Association of Genetic Variants with Postoperative Donor Artery Development in Moyamoya Disease: RNF213 and Other Moyamoya Angiopathy-Related Gene Analysis

Robust postoperative bypass development is a characteristic of moyamoya disease (MMD); however, genetic factors mediating this phenomenon remain incompletely understood. Therefore, we aimed to elucidate the relationship between postoperative donor artery development and genetic variants. We retrospectively enrolled 63 patients (79 hemispheres) who underwent combined revascularization surgery. Postoperative development of the superficial temporal artery (STA), middle meningeal artery, and deep temporal artery (DTA) was assessed using the caliber-change ratio determined from magnetic resonance angiography measurements. We analyzed RNF213 and 36 other moyamoya angiopathy-related genes by whole-exome sequencing and extracted rare or damaging variants. Thirty-five participants carried RNF213 p.Arg4810Lys (all heterozygotes), whereas 5 had RNF213 rare variants (RVs). p.Arg4810Lys was significantly associated with postoperative DTA development, while age at surgery, hypertension, and hyperlipidemia were inversely associated. Multiple regression analysis revealed that age and p.Arg4810Lys held statistical significance (P = 0.044, coefficient - 0.015, 95% confidence interval (CI) - 0.029 to 0.000 and P = 0.001, coefficient 0.670, 95% CI 0.269 to 1.072, respectively). Those with RNF213 RV without p.Arg4810Lys exhibited a significant trend toward poor DTA development (P = 0.001). Hypertension demonstrated a significant positive association with STA development, which remained significant even after multiple regression analysis (P = 0.001, coefficient 0.303, 95% CI 0.123 to 0.482). Following Bonferroni correction for multiple comparisons, targeted analyses of RNF213 and 36 moyamoya angiopathy-related genes showed a significant association of only RNF213 p.Arg4810Lys with favorable DTA development (P = 0.001). A comprehensive analysis of RNF213, considering both p.Arg4810Lys and RVs, may provide a clearer prediction of postoperative DTA development.

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.

GM-CSF Promotes the Development of Dysfunctional Vascular Networks in Moyamoya Disease

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease with the development of a network of abnormal vessels. Immune inflammation is associated with the occurrence and development of MMD. However, the mechanisms underlying the formation of the abnormal vascular network remain unclear. Twenty-eight patients with MMD, 26 ischemic stroke patients, and 26 unrelated healthy volunteers were enrolled in this study The data showed that the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) were higher in MMD patients than in healthy controls (P <0.01), and GM-CSF was mainly from Th1 and Th17 cells in MMD. We found that increased GM-CSF drove monocytes to secrete a series of cytokines associated with angiogenesis, inflammation, and chemotaxis. In summary, our findings demonstrate for the first time the important involvement of GM-CSF in MMD and that GM-CSF is an important factor in the formation of abnormal vascular networks in MMD.

Circulating immune cell landscape and T-cell abnormalities in patients with moyamoya disease

BACKGROUND

Moyamoya disease (MMD) stands as a prominent cause of stroke among children and adolescents in East Asian populations. Although a growing body of evidence suggests that dysregulated inflammation and autoimmune responses might contribute to the development of MMD, a comprehensive and detailed understanding of the alterations in circulating immune cells associated with MMD remains elusive.

METHODS

In this study, we employed a combination of single-cell RNA sequencing (scRNA-seq), mass cytometry and RNA-sequencing techniques to compare immune cell profiles in peripheral blood samples obtained from patients with MMD and age-matched healthy controls.

RESULTS

Our investigation unveiled immune dysfunction in MMD patients, primarily characterized by perturbations in T-cell (TC) subpopulations, including a reduction in effector TCs and an increase in regulatory TCs (Tregs). Additionally, we observed diminished natural killer cells and dendritic cells alongside heightened B cells and monocytes in MMD patients. Notably, within the MMD group, there was an augmented proportion of fragile Tregs, whereas the stable Treg fraction decreased. MMD was also linked to heightened immune activation, as evidenced by elevated expression levels of HLA-DR and p-STAT3.

CONCLUSIONS

Our findings offer a comprehensive view of the circulating immune cell landscape in MMD patients. Immune dysregulation in patients with MMD was characterized by alterations in T-cell populations, including a decrease in effector T-cells and an increase in regulatory T-cells (Tregs), suggest a potential role for disrupted circulating immunity in the aetiology of MMD.

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

BACKGROUND AND OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Nonalcoholic fatty liver disease is an independent risk factor for ischemic stroke after revascularization in patients with Moyamoya disease: a prospective cohort study

BACKGROUND

The study aimed to investigate the association between nonalcoholic fatty liver disease (NAFLD) and ischemic stroke events after revascularization in patients with Moyamoya disease (MMD).

METHODS

This study prospectively enrolled 275 MMD patients from September 2020 to December 2021. Patients with alcoholism and other liver diseases were excluded. NAFLD was confirmed by CT imaging or abdominal ultrasonography. Stroke events and modified Rankin Scale (mRS) scores at the latest follow-up were compared between the two groups.

RESULTS

A total of 275 patients were enrolled in the study, among which 65 were diagnosed with NAFLD. Univariate logistic regression analysis showed that NAFLD (P = 0.029) was related to stroke events. Multivariate logistic regression analysis showed that NAFLD is a predictor of postoperative stroke in MMD patients (OR = 27.145, 95% CI = 2.031-362.81, P = 0.013). Kaplan-Meier analysis showed that compared with MMD patients with NAFLD, patients in the control group had a longer stroke-free time (P = 0.004). Univariate Cox analysis showed that NAFLD (P = 0.016) was associated with ischemic stroke during follow-up in patients with MMD. Multivariate Cox analysis showed that NAFLD was an independent risk factor for stroke in patients with MMD (HR = 10.815, 95% CI = 1.259-92.881, P = 0.030). Furthermore, fewer patients in the NAFLD group had good neurologic status (mRS score ≤ 2) than the control group (P = 0.005).

CONCLUSION

NAFLD was an independent risk factor for stroke in patients with MMD after revascularization and worse neurological function outcomes.

Isolated anterior cerebral artery occlusion: an atypical form of moyamoya disease

BACKGROUND

The relationship between anterior cerebral artery (ACA) occlusion and moyamoya disease (MMD) has rarely been studied. In this study, we focused on a special type of MMD: isolated ACA-occlusive MMD. We investigated clinical attributes, genotypes and progression risk factors in patients with ACA-occlusive MMD, providing initial insights into the relationship between ACA occlusion and MMD.

METHODS

We retrospectively analysed digital subtraction angiography (DSA) from 2486 patients and diagnosed 139 patients with ACA-occlusive MMD. RNF213 p.R4810K (rs112735431) mutation analysis was performed. Patients were categorised into progression and non-progression groups based on whether they progressed to typical MMD. Differences in clinical characteristics, neuropsychological assessment, radiological findings and genotypes were evaluated. Logistic regression analyses identified risk factors for ACA-occlusive MMD progression.

RESULTS

The median age of patients with ACA-occlusive MMD was 36 years, and the primary symptom was transient ischaemic attack (TIA). 72.3% of ACA-occlusive MMD patients had cognitive decline. Of 116 patients who underwent RNF213 gene mutation analysis, 90 patients (77.6%) carried the RNF213 p.R4810K GG allele and 26 (22.4%) carried the GA allele. Of 102 patients with follow-up DSA data, 40 patients (39.2%) progressed. Kaplan-Meier curve estimates indicated a higher incidence of ischaemic stroke in the progression group during follow-up (p=0.035). Younger age (p=0.041), RNF213 p.R4810K GA genotype (p=0.037) and poor collateral compensation from the middle cerebral artery (MCA) to ACA (p<0.001) were risk factors of ACA-occlusive MMD progression to typical MMD.

CONCLUSIONS

Cognitive decline and TIA might be the main manifestations of ACA-occlusive MMD. Isolated ACA occlusion may be an early signal of MMD. The initial lesion site of MMD is not strictly confined to the terminal portion of the internal carotid artery. Younger patients, patients with RNF213 p.R4810K GA genotype or those with inadequate MCA-to-ACA compensation are more likely to develop typical MMD.

Be aware of childhood stroke: Proceedings from EPNS Webinar

Childhood arterial ischaemic stroke (AIS) is a significant health concern with increasing incidence. This review aims to provide an overview of the current understanding of childhood AIS. The incidence of childhood AIS is on the rise especially in developing countries, likely due to improved awareness and diagnostic capabilities. Aetiology of childhood AIS is multifactorial, with both modifiable risk factors and genetic predisposition playing important roles. Identifying and addressing these risk factors, such as infection, sickle cell disease, and congenital heart defects, is essential in prevention and management. Identifying underlying conditions through genetic testing is important for appropriate management and long-term prognosis. Clinically, distinguishing stroke from stroke mimics can be challenging. Awareness of important stroke mimics, including migraines, seizures, and metabolic disorders, is crucial to avoid misdiagnosis and ensure appropriate treatment. The diagnostic approach to childhood AIS involves a comprehensive "chain of care," including initial assessment, neuroimaging, and laboratory investigations. National guidelines play a pivotal role in standardizing and streamlining the diagnostic process, ensuring prompt and accurate management. Early intervention is critical in the management of childhood AIS. Due to the critical time window, the question if mechanical thrombectomy is feasible and beneficial should be addressed as fast as possible. Early initiation of antiplatelet or anticoagulation therapy and, in select cases, thrombolysis can help restore blood flow and minimize long-term neurological damage. Additionally, rehabilitation should start as soon as possible to optimize recovery and improve functional outcomes. In conclusion, childhood AIS is a growing concern. Understanding the increasing incidence, age distribution, risk factors, clinical presentation, diagnostic approach, and management strategies is crucial for optimized management of these patients.

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.

Paediatric Moyamoya disease: acute presentation with fever and confusion in an 8-year-old: a case report

Introduction and importance

Moyamoya is a chronic vaso-occlusive cerebrovascular disorder which involves internal carotid artery and its proximal branches, forming compensatory Moyamoya vessels. It may manifest with diverse symptoms, but early detection is crucial for a favourable prognosis.

Case presentation

The authors present a case of an 8-year-old child who presented to the emergency with acute onset fever and confusion in speech. Although the symptoms were vague, she was advised for a thorough investigation. MRI of the brain revealed an infarct on the brain that raised suspicion of a vaso-occlussive disorder. Subsequent magnetic resonance angiography and digital subtraction angiography revealed underlying Moyamoya disease.

Clinical discussion

Although the initial diagnosis of Moyamoya disease can be challenging, prompt diagnosis and simple medical measures like single antiplatelet regimens are useful for secondary ischaemic prevention.

Conclusion

This case highlights the essence of considering Moyamoya disease as one of the differentials while dealing with children presenting with subtle cerebrovascular symptoms.

Neuregulin 1 as a potential biomarker for disease progression in moyamoya disease: A case-control study in Chinese population

OBJECTIVE

Moyamoya disease (MMD) is a rare and progressive stenosis of cerebral arteries characterized by abnormally proliferative vasculopathy. Current studies have demonstrated that Neuregulin 1 (NRG1) plays a key role in angiogenesis-related disorders. Thus, the aim of our study is to investigate the serum NRG1 levels and their clinical correlations in MMD patients.

METHODS

In this study, thirty adult patients with MMD and age-gender matched healthy controls were enrolled from our hospital between July 2020 and April 2022. Peripheral blood samples were collected at baseline, and clinical data were obtained from the electronic medical record system. Serum NRG1 concentrations were measured by enzyme-linked immunosorbent assay. Sanger sequencing was applied to detect the RNF213 p.R4810K mutation.

RESULTS

The serum NRG1 levels were significantly higher in MMD patients compared to controls (14.48 ± 10.81 vs.7.54 ± 6.35mmol/L, p < 0.001). No statistical difference in baseline clinical characteristics was found between both groups. Correlation analyses showed that NRG1 levels were positively associated with Suzuki staging (r = 0.4137, p = 0.023) while not related to other clinical features (reduced cerebral blood flow, posterior cerebral artery involvement, bilateral or unilateral steno-occlusive changes). Furthermore, subgroup analysis revealed that MMD patients with the RNF213 p.R4810K mutation presented with significantly higher NRG1 levels than those without the mutation (9.60 ± 0.929 vs. 25.89 ± 4.338 mmol/L, p = 0.001).

CONCLUSIONS

Our study suggests that increased serum NRG1 levels may constitute a characteristic feature of MMD, indicating a potential positive correlation with disease progression and the presence of the RNF213 mutation. This positions NRG1 as a potentially crucial target for further studies aimed at comprehending the pathogenesis of MMD.

Association of lysine pathway metabolites with moyamoya disease

BACKGROUND AND OBJECTIVE

Lysine and its pathway metabolites have been identified as novel biomarkers for metabolic and vascular diseases. The role of them in the identification of moyamoya disease (MMD) has not been elucidated. This study aimed to determine the association between lysine pathway metabolites and the presence of MMD.

METHODS

We prospectively enrolled 360 MMD patients and 89 healthy controls from September 2020 to December 2021 in Beijing Tiantan Hospital. Serum levels of lysine, pipecolic acid and 2-aminoadipic acid were measured by liquid chromatography-mass spectrometry. We employed logistic regression and restricted cubic spline to explore the association between these metabolites and the presence of MMD. Stratified analyses were also conducted to test the robustness of results.

RESULTS

We observed that lysine levels in MMD patients were significantly higher and pipecolic acid levels were significantly lower compared to HCs (both p < 0.001), while no difference was found in the level of 2-AAA between both groups. When comparing metabolites by quartiles, elevated lysine levels were linked to increased odds for MMD (the fourth quartile [Q4] vs the first quartile [Q1]: odds ratio, 3.48, 95%CI [1.39-8.75]), while reduced pipecolic acid levels correlated with higher odds (Q4 vs Q1: odds ratio, 0.08; 95 % CI [0.03-0.20]). The restricted cubic spline found a L-shaped relationship between pipecolic acid level and the presence of MMD, with a cutoff point at 2.52 μmol/L. Robust results were also observed across subgroups.

CONCLUSION

Elevated lysine levels were correlated with increased odds of MMD presence, while lower pipecolic acid levels were associated with higher odds of the condition. These results suggest potential new biomarkers for the identification of MMD.

CLINICAL TRIAL REGISTRY NUMBER

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

Clinical Characteristics of Immediate Contralateral Ischemia Subsequent to Revascularization for Moyamoya Disease

BACKGROUND

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed.

METHODS

We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10 years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3 months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis.

RESULTS

The mean age was 34.5 (range: 5-71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429 G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44-71 years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF213 c.14429 G > A variant were patchy and peripheral. The other case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotid artery where patency had been confirmed preoperatively.

CONCLUSIONS

Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types.

Analyzing symptom experiences and pathways to enhancing quality of life in adolescents with Moyamoya disease

PURPOSE

The psycho-emotional symptom experiences and health-related factors that influence the quality of life of adolescents with Moyamoya disease are still not fully understood. The aim of this study is to identify the daily physical and accompanying psychological symptom experiences of such adolescents, and to examine how health-related factors contribute to their quality of life.

DESIGN AND METHOD

This study employed a descriptive cross-sectional research design. Data on a total of 134 adolescents with Moyamoya disease was analyzed in order to develop a path analysis. Data were collected from October 2019 to January 2021 in South Korea. The theory of salutogenesis was employed in order to develop a hypothetical model for this path analysis. Participants were given a self-reporting questionnaire. Descriptive analysis and path analysis were conducted based on the results.

RESULTS

Adolescents with Moyamoya disease experienced several negative emotions simultaneously, regardless of the severity of their physical symptoms. The path analysis revealed that stress, a sense of coherence, behavior, and the support of friends were significant contributors to adolescents' quality of life.

CONCLUSIONS

Adolescents with Moyamoya disease have multifaceted symptom experiences in their daily lives. To enhance their quality of life, it is crucial to provide support that can help strengthen their capacity for stress management and enhance their sense of coherence.

PRACTICAL IMPLICATIONS

This study provides evidence that nurses should offer anticipatory information to adolescents with Moyamoya disease regarding the symptoms they will frequently encounter, and develop interventions to enhance their quality of life.

Multiomics and blood-based biomarkers of moyamoya disease: protocol of Moyamoya Omics Atlas (MOYAOMICS)

BACKGROUND

Moyamoya disease (MMD) is a rare and complex cerebrovascular disorder characterized by the progressive narrowing of the internal carotid arteries and the formation of compensatory collateral vessels. The etiology of MMD remains enigmatic, making diagnosis and management challenging. The MOYAOMICS project was initiated to investigate the molecular underpinnings of MMD and explore potential diagnostic and therapeutic strategies.

METHODS

The MOYAOMICS project employs a multidisciplinary approach, integrating various omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, to comprehensively examine the molecular signatures associated with MMD pathogenesis. Additionally, we will investigate the potential influence of gut microbiota and brain-gut peptides on MMD development, assessing their suitability as targets for therapeutic strategies and dietary interventions. Radiomics, a specialized field in medical imaging, is utilized to analyze neuroimaging data for early detection and characterization of MMD-related brain changes. Deep learning algorithms are employed to differentiate MMD from other conditions, automating the diagnostic process. We also employ single-cellomics and mass cytometry to precisely study cellular heterogeneity in peripheral blood samples from MMD patients.

CONCLUSIONS

The MOYAOMICS project represents a significant step toward comprehending MMD's molecular underpinnings. This multidisciplinary approach has the potential to revolutionize early diagnosis, patient stratification, and the development of targeted therapies for MMD. The identification of blood-based biomarkers and the integration of multiple omics data are critical for improving the clinical management of MMD and enhancing patient outcomes for this complex disease.

Desmoglein-2 Affects Vascular Function in Moyamoya Disease by Interacting with MMP-9 and Influencing PI3K Signaling

The pathogenesis and development of Moyamoya disease are still unclear. This study aimed to investigate the effect of desmoglein-2 (DSG2) on Moyamoya disease and determine the inhibitory effect of DSG2 in vascular remodeling in Moyamoya disease.RNA sequencing, immunohistochemistry (IHC), and western blotting were used to detect the expression of DSG2 in the superficial temporal artery (STA) tissues of Moyamoya disease. The association between DSG2 and endothelial cells' biological activities was investigated by cell counting kit-8 (CCK-8), migration assay, tube formation assay, flow cytometry with Annexin V-FITC/PI staining, and TUNEL apoptotic cell detection kit. Pathways affected by overexpression or knockdown of DSG2 were identified in endothelial cells.The expression of DSG2 in the STA tissues of Moyamoya disease was lower than that in normal controls. Overexpression of DSG2 inhibits the proliferation and migration but promotes apoptosis in endothelial cells, and low DSG2 levels result in impaired angiogenesis. In addition, there was an interaction between DSG2 and MMP-9, and DSG2 acted through the PI3K signaling in endothelial cells.Our results indicate that DSG2 affects PI3K signaling in vascular endothelial cells, and MMP-9 is involved in DSG2-mediated vascular changes in Moyamoya disease.

Moyamoya Disease in a Child With Fanconi Anemia: An Anomaly or a Complication

Fanconi anemia (FA) is an inherited bone marrow failure syndrome associated with congenital anomalies and a predisposition to cancer. We report the case of a 9-year-old boy with FA who developed an abrupt onset of hemiplegia and dysarthria. The diagnosis of moyamoya disease (MMD) was suggested by magnetic resonance angiography (MRA) which demonstrated severe stenosis in the right internal carotid artery along with collateral vessel formation in the right basal ganglia. It is questioned whether the moyamoya pattern in this case is part of congenital malformations associated with FA or is the result of recurrent bleedings around the carotid siphon.

RNF213 in moyamoya disease: Genotype-phenotype association and the underlying mechanism

ABSTRACT

Moyamoya disease (MMD) is a cerebrovascular disorder characterized by a steno-occlusive internal carotid artery and compensatory vascular network formation. Although the precise pathogenic mechanism remains elusive, genetic association studies have identified RNF213 as the principal susceptibility gene for MMD, with the single nucleotide polymorphism p.R4810K recognized as the founder variant predominantly in the Asian populations. Distinct genotype-phenotype correlations are observable in RNF213-related MMD. The clinical manifestations linked to p.R4810K bear commonalities within Asian cohort, including familial predisposition, earlier age of onset, ischemic episodes, and involvement of the posterior cerebral artery (PCA). However, despite these shared phenotypic characteristics, there is significant heterogeneity in RNF213-related MMD presentations. This diversity manifests as variations across ethnic groups, inconsistent clinical symptoms and prognosis, and occurrence of other vasculopathies involving RNF213. This heterogeneity, in conjunction with the observed low disease penetrance of RNF213 mutations, suggests that the presence of these mutations may not be sufficient to cause MMD, underscoring the potential influence of other genetic or environmental factors. Although the current research might not have fully identified these additional contributors, experimental evidence points toward the involvement of RNF213 in angiogenesis, lipid metabolism, and the immune response. Future research is required to unveil the molecular mechanisms and identify the factors that synergize with RNF213 in the pathogenesis of MMD.

Synergistic Interaction of Thyroid Autoantibodies and Ring Finger Protein 213 Variant in Moyamoya Disease

Recently, thyroid autoantibodies were found to be associated with moyamoya disease (MMD). The ring finger protein 213 (RNF213) p.R4810K variant represents the most important susceptibility genotype of this disease, but its relationship with thyroid autoantibodies remains to be elucidated. Thus, in this study, we aimed to evaluate the clinical relevance of thyroid autoantibodies in each RNF213 genotype in patients with MMD. Included in this study were patients with MMD without a thyroid disease history and in euthyroid status; they were then classified into the mutated or nonmutated based on the RNF213 p.R4810K genotype and positive or negative based on thyroid autoantibody (thyroperoxidase and thyroglobulin) levels. Clinical data of each group were thereafter evaluated. Among the 209 patients, the mutated RNF213 p.R4810K variant and positive thyroid autoantibodies were detected in 155 and 41 patients, respectively. Positive thyroid autoantibodies were found to be more common in the nonmutated patients than in the mutated patients (31.5% vs. 15.5%; P = 0.011). In the mutated patients, as compared to autoantibody-negative patients, autoantibody-positive patients were determined to be more likely to have advanced disease with posterior cerebral artery involvement (54.2% vs. 29.0%; P = 0.017), white matter infarction (58.3% vs. 37.6%; P = 0.046), and a higher modified Rankin Scale at last visit (16.7% vs. 3.1%; P = 0.021). These results suggest that thyroid autoantibodies can act as an immunity inducer in patients with MMD lacking the susceptibility gene RNF213 p.R4810K variant. Moreover, the simultaneous presence of thyroid autoantibodies and the variant seems to aggravate the disease, which indicates synergy between thyroid autoantibodies and the variant.

National Institutes of Health grant funding for cerebrovascular diseases

BACKGROUND

Federal research funding is highly sought after but may be challenging to attain. A clear understanding of funding for specific diseases, such as cerebrovascular disorders, might help researchers regarding which National Institutes of Health (NIH) institutes fund research into specific disorders and grant types.

OBJECTIVE

To examine the current scope of NIH grant funding for cerebrovascular conditions.

METHODS

The NIH-developed RePORTER was used to extract active NIH-funded studies related to cerebrovascular diseases through January 2023. Duplicate studies were removed, and projects were manually screened and labeled in subcategories as clinical and basic science and as research subcategories. Extracted data included total funding, grant types, institutions that received funding, and diseases studied. Python (version 3.9) and SciPy library were used for statistical analyses.

RESULTS

We identified 1232 cerebrovascular projects across seven diseases with US$699 952 926 in total funding. The cerebrovascular diseases with the greatest number of grants were ischemic stroke (705, or 57.2% of all funded projects), carotid disease (193, or 15.7%), and hemorrhagic stroke (163, or 13.2%). R01 grants were the most common mechanism of funding (632 grants, or 51.3%). The National Institute of Neurological Disorders and Stroke (NINDS) funded the most projects (504 projects; US$325 536 405), followed by the National Heart, Lung, and Blood Institute (NHLBI) (376 projects; US$216 784 546).

CONCLUSION

Cerebrovascular disease receives roughly US$700 million in NIH funding. Ischemic stroke accounts for the majority of NIH-funded cerebrovascular projects, and R01 grants are the most common funding mechanism. Notably, NHLBI provides a large proportion of funding, in addition to NINDS.

Perry Disease: Bench to Bedside Circulation and a Team Approach

With technological applications, especially in genetic testing, new diseases have been discovered and new disease concepts have been proposed in recent years; however, the pathogenesis and treatment of these rare diseases are not as well established as those of common diseases. To demonstrate the importance of rare disease research, in this paper we focus on our research topic, Perry disease (Perry syndrome). Perry disease is a rare autosomal dominant neurodegenerative disorder clinically characterized by parkinsonism, depression/apathy, weight loss, and respiratory symptoms including central hypoventilation and central sleep apnea. The pathological classification of Perry disease falls under TAR DNA-binding protein 43 (TDP-43) proteinopathies. Patients with Perry disease exhibit DCTN1 mutations, which is the causative gene for the disease; they also show relatively uniform pathological and clinical features. This review summarizes recent findings regarding Perry disease from both basic and clinical perspectives. In addition, we describe technological innovations and outline future challenges and treatment prospects. We discuss the expansion of research from rare diseases to common diseases and the importance of collaboration between clinicians and researchers. Here, we highlight the importance of researching rare diseases as it contributes to a deeper understanding of more common diseases, thereby opening up new avenues for scientific exploration.

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.

Emerging Concept of Intracranial Arterial Diseases: The Role of High Resolution Vessel Wall MRI

Intracranial arterial disease (ICAD) is a heterogeneous condition characterized by distinct pathologies, including atherosclerosis. Advances in magnetic resonance technology have enabled the visualization of intracranial arteries using high-resolution vessel wall imaging (HR-VWI). This review summarizes the anatomical, embryological, and histological differences between the intracranial and extracranial arteries. Next, we review the heterogeneous pathophysiology of ICAD, including atherosclerosis, moyamoya or RNF213 spectrum disease, intracranial dissection, and vasculitis. We also discuss how advances in HR-VWI can be used to differentiate ICAD etiologies. We emphasize that one should consider clinical presentation and timing of imaging in the absence of pathology-radiology correlation data. Future research should focus on understanding the temporal profile of HR-VWI findings and developing quantitative interpretative approaches to improve the decision-making and management of ICAD.

Moyamoya Disease Causing Stroke in the Setting of Cocaine Use and Uncontrolled Hypertension Due to Primary Hyperaldosteronism

Moyamoya disease is a cerebrovascular disease characterized by stenosis of large intracranial arteries and the development of smaller collateral vessels. Moyamoya may cause strokes and stroke-like symptoms in young patients. It has also been linked to autoimmune diseases and neuropsychiatric conditions. We present a case of moyamoya disease in a young patient with concomitant hyperaldosteronism, uncontrolled hypertension, and cocaine use disorder, along with features of antisocial personality disorder. This is a unique presentation of an underlying neurological disease causing psychiatric features exacerbated by cocaine use, and it describes a rare clinical presentation that physicians should consider in patients with moyamoya disease.

Reconstruction of Scalp Defects Using Rotational Flaps After Revascularization Surgery in Patients with Moyamoya Disease

OBJECTIVE

Treating scalp defects after revascularization surgery is difficult because the scalp microcirculation is severely compromised. We aimed to review the clinical effects of using rotational flaps in scalp defect reconstruction and explore risk factors for wound-related complications (WRC) after reconstruction surgery.

METHODS

We retrospectively identified patients with scalp defects after combined revascularization surgery who were surgically treated with rotational flap reconstruction at our institution between January 2018 and December 2022. We analyzed treatment results in different surgical technique and revascularization strategy cohorts, including direct bypass superficial temporal artery branch selection, indirect bypass types, and skin incisions.

RESULTS

Eleven patients were included. The superficial temporal artery parietal branch was selected for direct bypass surgery in 10 (90.9%) patients, 4 (40%) of whom had WRC after flap reconstruction. Five types of indirect bypass surgeries were performed; three patients treated by encephalo-duro-myo-arterio-perio-synangiosis and 1 patient treated by encephalo-duro-myo-perio-synangiosis had WRC after flap reconstruction. Question mark (n = 6, 54.5%), curved (n = 4, 36.65%), and Y-shaped (n = 1, 9.1%) incisions were used; in the first three incision cohorts, 2 patients in each cohort had WRC after flap reconstruction.

CONCLUSIONS

Patients had the following commonalities that may be risk factors for WRC after flap reconstruction: 1) wounds with nonviable bone exposure after revascularization surgery; 2) three or more tissues used as donor tissues and donor tissues containing the periosteum; and 3) thin scalp around the defect.

RNF213-Related Vasculopathy: Various Systemic Vascular Diseases Involving RNF213 Gene Mutations: Review

Moyamoya disease (MMD) is a cerebrovascular disorder that is predominantly observed in women of East Asian descent, and is characterized by progressive stenosis of the internal carotid artery, beginning in early childhood, and a distinctive network of collateral vessels known as "moyamoya vessels" in the basal ganglia. Additionally, a prevalent genetic variant found in most MMD cases is the p.R4810K polymorphism of RNF213 on chromosome 17q25.3. Recent studies have revealed that RNF213 mutations are associated not only with MMD, but also with other systemic vascular disorders, including intracranial atherosclerosis and systemic vascular abnormalities such as pulmonary artery stenosis and coronary artery diseases. Therefore, the concept of "RNF213-related vasculopathy" has been proposed. This review focuses on polymorphisms in the RNF213 gene and describes a wide range of clinical and genetic phenotypes associated with RNF213-related vasculopathy. The RNF213 gene has been suggested to play an important role in the pathogenesis of vascular diseases and developing new therapies. Therefore, further research and knowledge sharing through collaboration between clinicians and researchers are required.

Detailed phenotype of RNF213 p.R4810K variant identified by the Chinese patients with acute ischaemic stroke or transient ischaemic attack

BACKGROUND AND PURPOSE

The ring finger protein 213 gene (RNF213) p.R4810K variant increased the risk of acute ischaemic stroke (AIS) attributable to intracranial arterial stenosis (ICAS) in the Japanese and Korean populations. In this study, we aimed to examine the prevalence of the RNF213 p.R4810K variant in Chinese patients with AIS or transient ischaemic attack and identify the phenotype of the carriers.

METHODS

We analysed data from the Third China National Stroke Registry. All included participants were divided into two groups by carrier status of the p.R4810K variant. The aetiological classification was conducted according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. The presence of ICAS and extracranial arterial stenosis (ECAS) was defined as 50%-99% stenosis or occlusion of any intracranial and extracranial artery. Logistic regression models and Cox regression models were used to evaluate the association of the p.R4810K variant with TOAST classification, stenosis phenotypes and clinical outcomes.

RESULTS

A total of 10 381 patients were enrolled, among which 56 (0.5%) had the heterozygote GA genotype for p.R4810K. The variant carriers were younger (p=0.01), and more likely to suffer from peripheral vascular disease (p=0.04). The p.R4810K variant was associated with large-artery atherosclerosis (LAA) (adjusted OR=1.94, 95% CI 1.13 to 3.33), anterior circulation stenosis (adjusted OR=2.12, 95% CI 1.23 to 3.65) and ECAS (adjusted OR=2.29, 95% CI 1.16 to 4.51). Nevertheless, the p.R4810K variant was not associated with recurrence, poor functional outcome and mortality at 3 months and 1 year.

CONCLUSIONS

The RNF213 p.R4810K variant was associated with LAA, anterior circulation stenosis and ECAS in Chinese patients. Given the low carrying rate and only 1-year follow-up information, caution should be taken to interpret our findings in no statistically significant association between the p.R4810K variant and stroke prognosis in Chinese patients.