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.

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

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

Proteomic and metabolomic characterizations of moyamoya disease patient sera.

BACKGROUND: The pathogenesis of moyamoya disease (MMD) is unclear. Inflammation and immune imbalance have been identified as potential factors contributing to the occurrence and progression of MMD. However, the specific proteins and metabolites responsible for triggering this process are yet to be established. The purpose of this study is to identify differentially expressed proteins and metabolites in patients with MMD and perform Kyoto Encyclopedia of Genes and Genomes pathway integration analysis to pinpoint crucial proteins and metabolites involved in the disease. METHODS: We performed untargeted metabolomic and data-independent acquisition proteomic analyses on the serum samples of individuals with MMD and healthy controls (HC). RESULTS: In patients with MMD versus HC, 24 proteins and 60 metabolites, including 21 anionic metabolites and 39 cationic metabolites, which were significantly different, were identified. In patients with MMD, several proteins involved in inflammation and immune metabolism, such as tubulin beta-6 and complement C4, were found to have significantly altered levels. Similarly, many metabolites involved in inflammation and immune metabolisms, such as dimethyl 4-hydroxyisophthalate, beta-nicotinamide mononucleotide, 2-(3-(4-pyridyl)-1H-1,2,4-triazol-5-yl)pyridine, and PC (17:1/18:2), were significantly altered. Intriguingly, these proteins and metabolites are involved in the progression of atherosclerosis through immune and inflammatory pathways, although some have never been reported in MMD. Moreover, integrated proteomics and metabolomics studies were conducted to determine shared pathways involving cholesterol metabolism, vitamin digestion, fat digestion, and absorption pathways of proteins and metabolites, which warrant further investigation. CONCLUSIONS: Significant increases in pro-inflammatory and immunosuppressive abilities have been observed in patients with MMD, accompanied by significant reductions in anti-inflammatory and immune regulation. Various metabolites and proteins implicated in these processes have been identified for the first time. These findings hold immense significance for comprehending the pathogenesis of MMD and for the development of future drug therapies.

Risk Factors for Preoperative Cerebral Infarction in Infants with Moyamoya Disease.

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

Natural course and risk factors of moyamoya disease with unruptured intracranial aneurysm.

Background and objective: The natural course and risk factors of moyamoya disease (MMD) associated with unruptured intracranial aneurysms involving stenosed parental arteries are scarcely studied. This study aimed to elucidate the natural course of MMD and its associated risk factors in patients with MMD with unruptured aneurysms. Methods: Between September 2006 and October 2021, patients with MMD with intracranial aneurysms at our center were examined. The natural course, clinical features, radiological features, and follow-up outcomes after revascularization were analyzed. Results: This study included 42 patients with MMD with intracranial aneurysms (42 aneurysms). The age distribution of MMD cases ranged from 6 to 69 years, with four children (9.5%) and 38 adults (90.5%). A total of 17 male and 25 female subjects were included (male-to-female ratio: 1:1.47). The first symptom was cerebral ischemia in 28 cases, and cerebral hemorrhage occurred in 14 cases. There were 35 trunk aneurysms and seven peripheral aneurysms. There were 34 small aneurysms (<5 mm) and eight medium aneurysms (5-15 mm). During the average clinical follow-up period of 37.90 ± 32.53 months, there was no rupture or bleeding from aneurysms. Twenty-seven of these patients underwent a cerebral angiography review, in which it was found that one aneurysm had enlarged, 16 had remained unchanged, and 10 had shrunk or disappeared. A correlation exists between the reduction or disappearance of aneurysms and the progression of the Suzuki stages of MMD (P = 0.015). Nineteen patients underwent EDAS on the aneurysm side, and nine aneurysms disappeared, while eight patients did not undergo EDAS on the aneurysm side and one aneurysm disappeared. Conclusion: The risk of rupture and hemorrhage of unruptured intracranial aneurysms is low when the parent artery already has stenotic lesions, thus, direct intervention may not be necessary for such aneurysms. The progression of the Suzuki stage of moyamoya disease may play a role in the shrinkage or disappearance of the aneurysms, thereby decreasing the risk of rupture and hemorrhage. Encephaloduroarteriosynangiosis (EDAS) surgery may also help promote atrophy or even the disappearance of the aneurysm, thus reducing the risk of further rupture and bleeding.

Protective Effect of Erythromycin Pre-adaptation on Focal Cerebral Ischemia in Rats and its Changes in TNF-α and nNOS.

Context: Ischemic stroke accounts for 85% of all types of stroke. Ischemic preconditioning can provide protection against cerebral ischemic injury. Erythromycin can induce ischemic preconditioning in brain tissue. Objective: The study intended to investigate the protective effects of erythromycin preconditioning on infarct volume after focal cerebral ischemia in rats and on the expression of tumor necrosis factor-alpha (TNF-α) and neuronal nitric oxide synthases (nNOS) in rat-brain tissue. Design: The research team performed an animal study. Setting: The study took place in the Department of Neurosurgery at the First Hospital of China Medical University in Shenyang, China. Animals: The animals were 60 healthy male Wistar rats, aged 6 to 8 weeks and weighing 270 to 300 g. Intervention: The research team randomly divided the rats into a control group in simple randomization and intervention groups preconditioning them according to their body weights using different concentrations of erythromycin-5, 20, 35, 50, and 65 mg/kg, with 10 rats in each group. The team induced focal cerebral ischemia and reperfusion using a modified, longa-wire embolization method. The control group, also 10 rats, received an injection intramuscularly of normal saline. Outcome Measures: The research team: (1) calculated the volume of cerebral infarction using triphenyltetrazolium chloride (TTC) staining with image analysis software and (2) investigated the effects of erythromycin preconditioning on the expression of TNF-α and nNOS mRNA and protein in the rat-brain tissue using real-time polymerase chain reaction (PCR) and Western blot. Results: Erythromycin preconditioning reduced the volume of cerebral infarction after induction of cerebral ischemia, showing a U-shaped, dose-response relationship, and the cerebral infarction volume significantly decreased in the 20-, 35-, and 50-mg/kg erythromycin preconditioning groups (P < .05). Erythromycin preconditioning at 20-, 35-, and 50-mg/kg significantly down-regulated the mRNA and protein expression of TNF-α in the rat-brain tissue (P < .05), with the 35-mg/kg erythromycin preconditioning group having the most significant downregulation. Erythromycin preconditioning at 20-, 35-, and 50-mg/kg upregulated the mRNA and protein expression of nNOS in the rat-brain tissue (P < .05), with the 35-mg/kg erythromycin preconditioning group having the most significant upregulation of the mRNA and protein of nNOS. Conclusions: Erythromycin preconditioning had a protective effect against focal cerebral ischemia in rats, and the best protective effect occurred for the 35-mg/kg preconditioning. The reason may be related to the fact that erythromycin preconditioning significantly upregulated nNOS and downregulated TNF-α in the brain tissue.

The Potential Mechanism Behind Native and Therapeutic Collaterals in Moyamoya.

Background and Purpose: To explore the genetic basis and molecular mechanism of native arteriogenesis and therapeutic synangiosis in moyamoya disease (MMD). Methods: An angiography-based study using patients from a prospective trial of encephaloduroarteriosynangiosis (EDAS) surgery was performed. The spontaneous collaterals grades were evaluated according to the system described by a new grading system. Blood samples were collected from all the recruited patients before EDAS and during the second hospitalization 3 months post-EDAS. We performed Boolean analysis using a combination of specific cell surface markers of CD34briCD133+CD45dimKDR+. Genotyping of p.R4810K was also performed. The correlation of age, sex, initial symptoms at diagnosis, collateral grade, Suzuki stages, the RNF213 genotype, time to peak (TTP), and endothelial progenitor cell (EPC) count with good collateral circulation was evaluated. Results: Eighty-five patients with MMD were included in this study. The mutation rate of RNF213 p.R4810K in our study was 25.9% (22/85). The heterozygous mutations were occurred significantly more frequently in the cases that were presented with infarction, worse neurological status, severe posterior cerebral artery (PCA) stenosis, and longer TTP delay. Further, the heterozygous mutations occurred significantly more frequently in the poor collateral stage group. Lower grades were significantly correlated with severe ischemia symptoms, worse neurological status, and a longer TTP delay. The post-operative angiographic findings showed that a good Matsushima grade was correlated with heterozygous mutations, a lower collateral stage, and a longer TTP delay. The CD34briCD133+CD45dimKDR+ cell count in patients 3 months post-EDAS was significantly higher as compared to the count before EDAS in the good Matsushima grade group. However, this change was not observed in the poor Matsushima grade group. Conclusions: These data imply that mutations of RNF213 p.R4810K affect the establishment of spontaneous collateral circulation, and EPCs are involved in the process of formation of new EDAS collaterals.

Recognition of the Effect of Indirect Revascularization for Moyamoya Disease: The Balance Between the Stage Progression and Neoangiogenesis.

Objective: To explore the long-term progression of neoangiogenesis after indirect revascularization for moyamoya disease (MMD). Methods: We enrolled patients who were diagnosed with MMD and treated by encephaloduroarteriosynangiosis (EDAS) surgery at our center from December 2002 through September 2009. A comparative study between short-term (6-12 months) and long-term (duration ≥ 8 years) follow-up angiographies was performed. The development of collateral circulation through EDAS was graded according to the system described by the Matsushima grade system. Results: A total of 78 patients who received indirect EDAS were enrolled in the study. The mean age at the first operation was 26.9 ± 15.0 years. The Matsushima grades of the same hemisphere were higher at the long-term follow-up compared with the short-term follow-up. Importantly, no attenuation was observed in any hemisphere during the long-term follow-up. In total, 51 hemispheres (32.7%) and 26 hemispheres (16.6%) had progression during the short-term and the long-term follow-up, respectively. The ipsilateral Suzuki stage showed a significant negative correlation with progression pace. Furthermore, higher Suzuki stages were significantly correlated with the postsurgical Matsushima grade at both time points. A total of nine strokes (11.5%) occurred in 78 patients was reported at the long-term follow-up. The annual incidence rate of recurrent strokes was higher for the stage progression group than for the stable group. Conclusion: For patients with MMD, postsurgical neoangiogenesis after indirect bypass continuously improved with time. The short-term progression of the internal carotid artery (ICA) might be attributed to cerebral revascularization, while the long-term progression should be attributed to the natural progression of the disease.

Dynamic Changes of Collateral Vessels After Encephaloduroarteriosynangiosis in Moyamoya Disease: Childhood to Adulthood.

BACKGROUND: Moyamoya disease (MMD) often presents as ischemic stroke in pediatric patients and hemorrhage in adults. This situation raises questions as to whether the phenotype of moyamoya disease changes with age. OBJECTIVE: We performed self-precontrol and postcontrol observation monitoring until adulthood on abnormal collateral vessels (ACVs) with the potential risk of bleeding to evaluate the chance of further hemorrhage. METHODS: Fifteen pediatric patients with >10 years angiography-based follow-up were analyzed. The Matsushima grades were divided into 2 groups (good group, representing Matsushima stage A; and mild group, representing Matsushima stages B and C) to investigate the relationship between Matsushima grades and ACVs derived from vessels likely to cause intracranial hemorrhage. RESULTS: Four patients (26.7%) had infarction type and 11 (73.3%) patients had transient ischemic attack type. No patient experienced late-onset cerebral hemorrhagic events. One patient experienced recurrent ischemic stroke 6 months after the second surgery and recovered completely after the third surgery. The angiography-based follow-up was conducted at least 10 years after the encephaloduroarteriosynangiosis (EDAS). The good Matsushima group showed a significant positive correlation with the reduction of the anterior choroidal artery (odds ratio, 56.00; P = 0.003), whereas the posterior communicating artery showed no significant decrease before and after the EDAS procedure (odds ratio, 2.00; P = 1.00). CONCLUSIONS: The EDAS procedure can effectively attenuate the dilation and ACVs of the anterior choroidal artery, which may reduce the incidence of further hemorrhage in adulthood.

Validation and Extension Study Exploring the Role of RNF213 p.R4810K in 2,877 Chinese Moyamoya Disease Patients.

OBJECTIVE: To validate, update, and extend the role of RNF213 p.R4810K (G>A) for predicting the phenotype of moyamoya disease (MMD) patients and explore the different effects on pediatric and adult groups. METHODS: A total of 2,877 patients conducted from 2004 to 2018 were included. Review Manage 5.3 and SPSS 20.0 were applied to complete all statistical analyses. Information on age at onset, sex, initial symptom, family history and complications were obtained via retrospective chart review. Angiographic records were evaluated. RESULTS: In China, geographic proximity to Korea or Japan may affect the carrying rate of RNF213 p.R4810K. The proportion of patients with the following characteristics was significantly higher (P <0.017) in the GA than in the GG group: female, age at onset < 18 years, infarct after transient ischemic attack, family history of MMD, and posterior cerebral artery involvement. For pediatric patients, GA showed more cerebral hemorrhage (CH) (odds ratios (ORs) [95% confidence intervals (CIs)] = 3.99 (1.61-9.88), P = 0.003), more patients were in the Suzuki early and intermediate stage (P = 0.001; P = 0.001, respectively), while for the adult group, GA indicated more female (OR [95% CIs] = 1.43 [1.15-1.79], P = 0.001), fewer patients with diabetes (0.58 [0.38-0.86], P = 0.007) and intermediate Suzuki stage (P = 3.70 × 10-4). CONCLUSIONS: The incidence and carrying rates of RNF213 p.R4810K in various regions for Chinese MMD patients were obviously different. RNF213 p.R4810K has different predictive effects on phenotypes of pediatric and adult patients.

Clinical and Genetic Risk Factors of Long-Term Outcomes after Encephaloduroarteriosynangiosis in Moyamoya Disease in China.

OBJECTIVES: This retrospective study was conducted to analyze the associations between ring finger protein 213 p.R4810K variant, clinical features and long-term outcomes in patients with moyamoya disease (MMD) after encephaloduroarteriosynangiosis treatment. MATERIALS AND METHODS: A total of 2,545 patients with MMD in China were included in this study (median of follow-up duration: 32.00 months). Multiple Cox regression models were used to assess the associations between p.R4810K variant, clinical features and long-term outcomes. RESULTS: For all patients, in multivariate Cox analysis, no association was observed between p.R4810K and long-term outcomes. Pediatric onset (HR, 0.38; 95%CI, 0.25-0.59) and headache (HR, 0.26; 95%CI, 0.08-0.83) were inversely and hypertension (HR, 1.43 95%CI, 1.06-1.94), diabetes (HR, 1.55; 95%CI, 1.00-2.40), bilateral lesions (HR, 2.73; 95%CI, 1.12-6.65) and posterior cerebral artery involvement (HR, 1.44; 95%CI, 1.08-1.90) were positively associated with follow-up stroke (all P < 0.05). Pediatric onset (HR, 0.46; 95%CI, 0.26-0.82) was inversely and hyperlipidemia (HR, 1.83; 95%CI, 1.23-2.73), smoking (HR, 1.86; 95%CI, 1.13-3.07), high Suzuki angiographic stage (HR, 1.71, 95%CI, 1.09-2.70), poor admission neurologic status (HR, 8.93; 95%CI, 6.49-12.29) and follow-up stroke (HR, 8.31; 95%CI, 6.01-11.49) were positively associated with poor neurologic outcome at the last follow-up visit (all P < 0.05). The factors were not consistent in the different groups of age at onset. CONCLUSIONS: In our study, p.R4810K may play no role in long-term outcomes in Chinese MMD. Clinical features including age at onset, initial symptoms, risk factors of stroke, imaging, poor admission neurologic status were associated with poor outcomes in MMD after EDAS.

Erythromycin pretreatment induces tolerance against focal cerebral ischemia through up-regulation of nNOS but not down-regulation of HIF-1α in rats.

The purpose of this study was to determine whether the antibiotic erythromycin induces tolerance against focal cerebral ischemia, and the possible underlying mechanism including the involvement of neuronal nitric oxide synthase (nNOS) and hypoxia-inducible factor-1α (HIF-1α). In rat focal cerebral ischemia models, we found that erythromycin preconditioning could significantly decrease the cerebral infarct volume and brain edema. Meanwhile, the neurological deficits from day 4 through 7 after surgery were also remarkably decreased after erythromycin preconditioning. Moreover, erythromycin preconditioning induced significantly increased nNOS levels and decreased HIF-1α levels in both mRNA and protein expression. This study for the first time indicated that erythromycin preconditioning could induce focal brain ischemic tolerance and attenuate brain injury of subsequent transient focal cerebral ischemia. The potential mechanism may be due to up-regulation of nNOS, but the HIF-1α system was not involved.