Postoperative Neovascularization, Cerebral Hemodynamics and Clinical Prognosis Between Combined and Indirect bypass Revascularization Procedures in Hemorrhagic Moyamoya Disease.

Abstract BACKGROUND: Present primary focus was rebleeding and prognosis of hemorrhagic moyamoya disease (MMD), while limited researches emphasized the postoperative collateral formation and cerebral hemodynamics. OBJECTIVE: To compare the diverse effects of combined (CB) and indirect (IB) bypass revascularization procedures on the postoperative collateral formation and hemodynamics in hemorrhagic MMD patients.METHODS: Hemorrhagic MMD patients treated surgically were retrospectively collected and dichotomized into CB and IB group. Postoperative complications and clinical prognosis, as well as pre- and post-operative Modified Rankin Scale (mRS), collateral circulation status and cerebral hemodynamics were observed and compared between the CB and IB groups. RESULTS: A total of 37 patients with hemorrhagic MMD were identified. Of 68 cerebral hemispheres, 47(69.1%) were combined revascularization and the rest indirect. During an average follow-up of 16.5±8.7 months, the recurrent stroke events were significantly lower, as well as postoperative mRS scores≤2, satisfactory postoperative collateral formation, improved dilation or extension of anterior choroidal /posterior communication artery (AchA/PcoA) were significantly higher in the CB group than in the IB group (all P< .05). Compared with preoperative cerebral hemodynamics, relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), mean transit time (MTT) and relative time to peak (rTTP) in the CB group; but in the IB group, rCBF, rCBV and MTT were significantly improved (all P< .001). The CB group’s postoperative rCBF was significantly improved as compared with the IB group (P< .001).CONCLUSION: CB can obtain better postoperative collateral formation, cerebral hemodynamics, and clinical prognosis as compared with IB.