Association between angiographic and clinical outcomes after STA-MCA bypass in adult moyamoya disease

As an angiographic outcome, postoperative collateral formation (PCF) is commonly used to evaluate the effect of STA-MCA bypass in moyamoya disease (MMD), but whether it can reliably reflect clinical outcomes is still unclear. We investigated the association between PCF and clinical outcomes in adult MMD.

All STA-MCA bypass procedures performed from January 2013 to December 2019 were screened in this prospective cohort study. Patients who acquired presurgical and follow-up catheter angiography were included. The clinical outcomes consisted of symptom improvement and recurrent cerebrovascular events. Logistic and Cox regression and Kaplan-Meier analyses were performed to explore the association between PCF and clinical outcomes.

Of 165 included symptomatic hemispheres of 154 patients, 104 (63.0%) and 61 (37.0%) had good and poor PCF, respectively. The hemispheres with good PCF were younger (p = 0.004) and had a higher incidence of hemodynamic dysfunction on admission (p < 0.001) than those with poor PCF. Multivariate logistic regression analysis showed that the good PCF (odd ratio, 28.96; 95% confidence interval (CI), 9.12-91.98; p < 0.001) was associated with a higher incidence of symptom improvement. Multivariate Cox regression analysis showed that the poor PCF (hazard ratio, 3.77; 95% CI, 1.31-10.84; p = 0.014) was associated with a higher incidence of recurrent cerebrovascular events. In the hemorrhagic-onset hemispheres, good PCF group had a higher incidence of symptom improvement (p < 0.001) and a longer hemorrhage-free time (p = 0.031). In the ischemic-onset hemispheres, good PCF group also had a higher incidence of symptom improvement (p < 0.001) and a longer ischemia-free time (p = 0.028).

As a angiographic outcome, collateral formation is a qualified surrogate measure for clinical outcomes after STA-MCA bypass in adult MMD.