Abstract: Objective To explore the clinical value of vessel encoded arterial spin-labeling (VE-ASL) magnetic resonance in evaluating direct revascularization in patients with moyamoya disease. Methods Fifty-six patients with Moyamoya disease who underwent middle cerebral artery (MCA)-superficial temporal artery (STA) anastomosis in Beijing Tiantan Hospital were retrospectively analyzed. 3.0T VE-ASL was performed preoperatively and within 1 week postoperatively. Preoperative and postoperative perfusion territories of the bilateral internal carotid arteries, bilateral external carotid arteries, and basilar artery were examined, and the revascularization area was examined by labeling the superficial temporal artery-to-middle cerebral artery bypass postoperatively. Computed tomography angiography (CTP) was performed and compared with VET-ASL results. Results Of the 56 patients, mean values of cerebral blood flow (CBF) from VE-ASL in the anastomosis side at preoperative assessment and 7 days postoperative follow-up were (349±55) mL·kg^-1·min^-1 and (558±74) mL·kg^-1·min^-1 (P<0.01),respectively. At 7days after operation, 36(64.2%)patients VE-ASL demonstrated the blood flow from STA, whereas 20(35.7%)patients had no blood flow from STA. Of them, 6 patients restore blood flow from STA at 3 months after operation. Compared with VE-ASL, CBF of 39(69.6%) and 44(78.5%) patients was improved at 7 days and 3 months, respectively, after operation based on CTP scan. There was good intermodality agreement between VE-ASL and CTP in evaluating the CBF changes at 7days or 3 months after revascularization (7 days Kappa=0.718; 3 months,Kappa=0.744). Conclusion VE-ASL is a promising technique in evaluation of patients with Moyamoya disease, which could provide quantitative assessment of the postoperative CBF changes after direct revascularization.

Key words: vessel encoded arterial spin-labeling, moyamoya disease, direct revascularization