Cerebral revascularization surgery reduces cerebrovascular events in children with sickle cell disease and moyamoya syndrome: Results of the stroke in sickle cell revascularization surgery retrospective study.

BACKGROUND: Recent studies suggest that cerebral revascularization surgery may be a safe and effective therapy to reduce stroke risk in patients with sickle cell disease and moyamoya syndrome (SCD-MMS). METHODS: We performed a multicenter, retrospective study of children with SCD-MMS treated with conservative management alone (conservative group)-chronic blood transfusion and/or hydroxyurea-versus conservative management plus surgical revascularization (surgery group). We monitored cerebrovascular event (CVE) rates-a composite of strokes and transient ischemic attacks. Multivariable logistic regression was used to compare CVE occurrence and multivariable Poisson regression was used to compare incidence rates between groups. Covariates in multivariable models included age at treatment start, age at moyamoya diagnosis, antiplatelet use, CVE history, and the risk period length. RESULTS: We identified 141 patients with SCD-MMS, 78 (55.3%) in the surgery group and 63 (44.7%) in the conservative group. Compared with the conservative group, preoperatively the surgery group had a younger age at moyamoya diagnosis, worse baseline modified Rankin scale scores, and increased prevalence of CVEs. Despite more severe pretreatment disease, the surgery group had reduced odds of new CVEs after surgery (odds ratio = 0.27, 95% confidence interval [CI] = 0.08-0.94, p = .040). Furthermore, comparing surgery group patients during presurgical versus postsurgical periods, CVEs odds were significantly reduced after surgery (odds ratio = 0.22, 95% CI = 0.08-0.58, p = .002). CONCLUSIONS: When added to conservative management, cerebral revascularization surgery appears to reduce the risk of CVEs in patients with SCD-MMS. A prospective study will be needed to validate these findings.

Indications for cerebral revascularization for moyamoya syndrome in pediatric sickle cell disease determined by Delphi methodology.

OBJECTIVE: Cerebral revascularization surgery (CRS) has been used to prevent stroke in children with sickle cell disease (SCD) and cerebral vasculopathy (e.g., moyamoya syndrome). While results suggest that it may be an effective treatment, surgical indications have not been well defined. This study sought to determine indications for offering revascularization surgery in centers with established sickle cell programs in the US. METHODS: Three sequential surveys utilizing the Delphi methodology were administered to neurosurgeons participating in the Stroke in Sickle Cell Revascularization Surgery study. Respondents were presented with clinical scenarios of patients with SCD and varying degrees of ischemic presentation and vasculopathy, and the group's agreement to offer surgical revascularization was measured. Consensus was defined as ≥ 75% similar responses. RESULTS: The response rate to all 3 surveys was 100%. Seventeen neurosurgeons from 16 different centers participated. The presence of moyamoya collaterals (MMCs) and arterial stenosis matching an ischemic distribution yielded the strongest recommendations to offer surgery. There was consensus to offer revascularization in the presence of MMCs and at least 50% arterial stenosis matching an ischemic distribution. In contrast, there was no consensus to offer revascularization with 50%-70% stenosis not matching an ischemic presentation in the absence of MMCs. The presence of the ivy sign in the distribution of the stenotic artery also contributed to the consensus to offer surgery in certain scenarios. CONCLUSIONS: There were several clinical scenarios that attained consensus to offer surgery; the strongest was moderate to severe arterial stenosis that matched the distribution of ischemic presentation in the presence of MMCs. Radiological findings of decreased cerebral flow or perfusion also facilitated attaining consensus to offer surgery. The findings of this study reflect expert opinion about questions that deserve prospective clinical research. Determination of indications for CRS can guide clinical practice and aid the design of prospective studies.