Object: Superficial temporal artery to middle cerebral artery (STA-MCA) bypass is the most effective treatment for Moyamoya disease (MMD). In this study, we aimed to assess whether aspirin improves STA-MCA bypass patency and is safe in patients with MMD. Methods: We performed a retrospective medical record review of patients with ischaemic-onset MMD who had undergone STA-MCA bypass at two hospitals between January 2011 and August 2018, to clarify the effects and safety of aspirin following STA-MCA bypass. The neurological status at the last follow-up (FU) was compared between patients with FU bypass patency and occlusion. Results Among 217 identified patients (238 hemispheres), the mean age was 41.4±10.2 years, and 51.8% were male; the indications for STA-MCA bypass were stroke (48.2%), followed by a transient ischaemic attack (44.0%). Immediate bypass patency was confirmed in all cases. During the FU period (1.5±1.5 y), 15 cases were occluded at FU imaging, resulting in an overall cumulative patency rate of 94%. The patency rates were 93% and 94% in the short-term FU group (n=131, mean FU time 0.5±0.2 years) and long-term FU group (n=107, mean FU time 4.1±3.5 years), respectively. The STA-MCA bypass patency rate in the aspirin group was higher than that in the non-aspirin group (98.7% vs 89.7%; HR 1.57; 95% CI 1.106 to 2.235; p=0.012). No significant difference in the FU haemorrhagic events was observed between the aspirin and non-aspirin groups. Conclusions: Among adult patients with ischaemic-onset MMD undergoing STA-MCA bypass procedures, aspirin might increase the bypass patency rate, without increasing the bleeding risk. FU bypass patency may be associated with a better outcome. Additional studies, especially carefully designed prospective studies, are needed to address the role of aspirin after bypass procedures.

Aims: To assess differences in the clinical prognosis between different treatment timings in poor‐grade (Hunt and Hess grade 4–5) aneurysmal subarachnoid hemorrhage patients.Methods: The treated 127 poor‐grade aneurysmal subarachnoid hemorrhage patients were divided into three groups: early treatment within 2 days, treatment on days 3 to 10, and treatment for more than 10 days after the hemorrhage. Odd ratios with a 95% confidence interval were calculated in logistic regression for different timing strategies regarding delayed cerebral ischemia and poor prognosis at 3 months. Subgroup analyses were conducted to determine whether the different timing strategies affect the prognosis.Results: Patients who received the treatment on days 3 to 10 were prone to develop delayed cerebral ischemia and poor prognosis at 3 months. Postponing treatment in patients older than 55 years or diagnosed with an intraventricular hematoma on the initial computed tomography scan may lead to poor prognosis, with the early intervention group as a reference.Conclusions: Early intervention in poor‐grade aneurysmal subarachnoid hemorrhage is suggested to be implemented. The treatment on 3 to 10 days harbored the highest risk of poor prognosis; patients might benefit more from early intervention, especially for ones older than 55 years or diagnosed with an intraventricular hematoma.

Background: Coexistence of intracranial atherosclerotic stenosis (ICAS) and unruptured intracranial aneurysms (UIAs) is increasingly encountered in clinical practice. This study aims to determine the prevalence of ICAS in patients with UIAs and procedural ischemic risk associated with ICAS when treating UIAs. Methods: Based on the CAIASA study (Coexistence of Atherosclerotic Intracranial Arterial Stenosis With Intracranial Aneurysms), we prospectively included patients undergoing treatment procedures for UIAs from October 2015 to December 2020 at Beijing Tiantan Hospital, China. We used computed tomography angiography or digital subtraction angiography to diagnose ICAS (stenosis≥50%). Multivariable logistic regression and propensity-score matching were performed to evaluate the risk of procedure-related ischemic stroke and unfavorable outcome associated with ICAS. The ICAS score was used to explore the association between different burden of ICAS and procedure-related ischemic risk. Results: Among 3949 patients who underwent endovascular or open surgical procedures for UIAs, 245 (6.2%) had ICAS. After exclusion, 15.7% (32/204) of patients with ICAS experienced procedure-related ischemic stroke compared with 5.0% (141/2825) of patients without ICAS. From the unmatched and matched cohort, ICAS was significantly associated with increased risk of procedure-related ischemic stroke (unmatched: adjusted odds ratio=3.11 [1.89–5.11]; and matched: adjusted odds ratio=2.99 [1.38–6.48]). This association became more evident among patients not receiving antiplatelet therapy ( P _interaction =0.022). For patients undergoing different treatment modalities, similar increased risks were observed (clipping: adjusted odds ratio=3.43 [1.73–6.79]; and coiling: adjusted odds ratio=3.59 [1.94–6.65]). Higher ICAS score was correlated with higher procedural ischemic risk ( P _trend <0.001). Conclusions: The occurrence of ICAS is not infrequent in patients with UIAs. ICAS confers an ~2-fold increased procedural ischemic risk, irrespective of clipping or coiling. Previous antiplatelet therapy may decrease the risk. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02795078.

Rapid formation of innovative, inexpensive, personalized, and quickly reproducible artery bioresorbable stents (BRSs) is significantly important for treating dangerous and sometimes deadly cerebrovascular disorders. It is greatly challenging to give BRSs excellent mechanical properties, biocompatibility, and bioabsorbability. The current BRSs, which are mostly fabricated from poly-l-lactide (PLLA), are usually applied to coronary revascularization but may not be suitable for cerebrovascular revascularization. Here, novel 3D-printed BRSs for cerebrovascular disease enabling anti-stenosis and gradually disappearing after vessel endothelialization are designed and fabricated by combining biocompatible poly (p-dioxanone) (PPDO) and 3D printing technology for the first time. We can control the strut thickness and vessel coverage of BRSs by adjusting the printing parameters to make the size of BRSs suitable for small-diameter vascular use. We added bis-(2,6-diisopropylphenyl) carbodiimide (commercial name: stabaxol^®-1) to PPDO to improve its hydrolytic stability without affecting its mechanical properties and biocompatibility. In vitro cell experiments confirmed that endothelial cells can be conveniently seeded and attached to the BRSs and subsequently demonstrated good proliferation ability. Owing to the excellent mechanical properties of the monofilaments fabricated by the PPDO, the 3D-printed BRSs with PPDO monofilaments support desirable flexibility, therefore offering a novel BRS application in the vascular disorders field.

Background: The mechanisms driving the progression of moyamoya disease (MMD) remain unrecognized. There is evidence suggesting that genetic and environmental factors may be associated with intracranial artery stenosis. Here, we aimed to investigate the characteristics of infectious exposure and the association of the RNF213 (RING finger protein 213) variant and infectious burden (IB) with intracranial artery stenosis of MMD. Methods and Results: We prospectively recruited 275 patients with MMD. Participants underwent RNF213 p.R4810K sequencing. Serum antibody titers of herpes simplex virus, cytomegalovirus, toxoplasma, rubella virus, and Epstein‐Barr virus were assessed and combined into an IB score. The degree of intracranial artery stenosis was measured by using the Willis narrowing score (WNS), which was then dichotomized as mild and severe. Multivariate regression analyses were performed to analyze variables associated with severe WNS. Patients with the RNF213 variant had a higher risk of severe WNS than wild‐type individuals ( P =0.003). Patients with MMD with severe WNS showed an increased level of IB score ( P <0.001). The RNF213 variant (odds ratio [OR], 2.832 [95% CI, 1.347–5.955]; P =0.006) and IB score (OR, 1.771 [95% CI, 1.286–2.439]; P <0.001) were significantly associated with severe WNS after adjusting for covariates. Furthermore, the associations between IB score and severe WNS were more prominent among patients with modifiable risk factors of elevated body mass index ( P _interaction <0.001), triglycerides ( P _interaction =0.011), and homocysteine ( P _interaction =0.016). Conclusions: This study outlined a perspective of the genetic‐environmental interactions in the progression of MMD. The RNF213 variant and increased IB were associated with intracranial artery stenosis in MMD. The study will provide novel insights into the mechanism of disease progression, which may offer opportunities for early intervention of infectious exposure in MMD.

Background: Intracranial aneurysms pose a significant health issue, affecting 3–5% of the adult population. The pipeline embolization device (PED) has emerged as a promising treatment for these lesions. This study aimed to investigate the impact of operator experience on complication and poor outcome rates, as well as the learning curve for PED. Methods: A total of 217 patients were consecutively enroled from four eligible centres and divided into three groups based on the number of procedures performed: group 1 (first 10 procedures), group 2 (11–20 procedures), and group 3(>20 procedures). Major complications include operation-related ischaemic or haemorrhagic events and mass effect deterioration. Poor outcome was defined as a modified Rankin Scale score greater than 2 at discharge. Cumulative summation (CUSUM) analysis was generated to assess the learning curve according to major complications and poor outcome. Results: The study found that major complications and poor outcomes occurred in 5.1% and 2.3% of cases, respectively. The rate of major complications decreased from 10.0% in group 1 to 2.9% in group 3 (P=0.053), while the rate of poor outcomes decreased from 7.5% in group 1 to 0.7% in group 3 (P=0.015). Multivariable regression analysis adjusted for covariates showed that operator experience was associated with a lower rate of poor outcomes (P=0.034). CUSUM analysis demonstrated that the learning curve for avoiding major complications and poor outcomes required 27 (mean=13) and 40 (mean=20) cases, respectively. Conclusions: These findings suggest that PED treatment requires a learning curve of 40 cases to achieve reproducibility regarding complications and functional results. Additionally, major complications and poor outcomes significantly decreases after the first 20 procedures. CUSUM analysis can serve as a useful tool for monitoring and assessing surgical performance.