Direct vs Indirect Revascularization in a North American Cohort of Moyamoya Disease
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Published on: January 23, 2019
Pui Man Rosalind Lai1, Nirav J Patel1, Kai U Frerichs1
1Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Background:
In adults with ischemic moyamoya disease (MMD), the efficacy of direct vs indirect revascularization procedures remains a matter of debate.
Objective:
To investigate the outcomes of ischemic MMD in a North American cohort treated by direct and indirect revascularizations.
Methods:
We retrospectively reviewed medical records of adult patients with MMD with ischemic presentation from 1984 to 2018 at the Brigham and Women's Hospital and Massachusetts General Hospital who underwent either direct or indirect bypasses. Early postoperative events and outcome at more than 6 mo postoperatively were evaluated using multivariable logistic regression analyses. Multivariable Cox proportional hazards regression analyses were used to evaluate delayed ischemic and hemorrhagic events. Analyses were performed per hemisphere.
Results:
A total of 95 patients with MMD and 127 hemispheres were included in this study. A total of 3.5% and 8.6% of patients had early surgical complications in the direct and indirect bypass cohorts, respectively (P = .24). Hemispheres with direct bypasses had fewer long-term ischemic and hemorrhagic events at latest follow-up (adjusted hazard ratio [HR] 0.19, 95% confidence interval [CI] 0.058-0.63, P = .007; median follow-up 4.5 [interquartile range, IQR 1-8] yr). There was no difference between the direct and indirect bypass groups when the endpoint was limited to infarction and hemorrhage only (P = .12). There was no difference in outcome (modified Rankin Scale [mRS] ≥ 3) between the 2 cohorts (P = .92).
Conclusion:
There was no difference in early postoperative events, long-term infarction or hemorrhage, or clinical outcome between direct and indirect revascularization. However, there was a significant decrease in all ischemic and hemorrhagic events combined in direct revascularizations compared to indirect revascularizations.
Insights
Direct revascularization for moyamoya disease (MMD) showed fewer long-term ischemic and hemorrhagic events. While early complications and overall outcomes were similar, direct bypasses reduced combined events in this North American cohort.
Area of Science:
- Neurosurgery
- Neurology
- Vascular Surgery
Background:
- Moyamoya disease (MMD) is a rare cerebrovascular disorder characterized by progressive stenosis of intracranial arteries.
- The optimal surgical strategy for ischemic MMD, specifically direct versus indirect revascularization, is debated.
- This study addresses the efficacy of these procedures in a North American adult cohort.
Purpose of the Study:
- To compare the outcomes of direct versus indirect revascularization in adult patients with ischemic moyamoya disease.
- To evaluate early postoperative complications, long-term ischemic events, and overall clinical outcomes.
Main Methods:
- Retrospective review of adult MMD patients with ischemic presentation (1984-2018).
- Inclusion of patients who underwent either direct or indirect bypass surgery.
- Analysis of early and late outcomes using multivariable logistic and Cox proportional hazards regression models, performed per hemisphere.
Main Results:
- Direct bypasses were associated with significantly fewer long-term ischemic and hemorrhagic events combined (adjusted HR 0.19, P=0.007).
- No significant differences were observed in early surgical complications (3.5% vs 8.6%, P=0.24) or outcomes (mRS ≥3, P=0.92) between the two groups.
- When limited to infarction and hemorrhage alone, no difference was found between direct and indirect revascularization (P=0.12).
Conclusions:
- Direct revascularization demonstrated a significant reduction in the combined incidence of all ischemic and hemorrhagic events compared to indirect revascularization.
- Despite this, no significant differences were found in early postoperative events, long-term infarction/hemorrhage alone, or overall clinical outcomes (mRS).
- The findings suggest a benefit of direct bypass in reducing the overall burden of cerebrovascular events in ischemic MMD.
