Preoperative evaluation of moyamoya spontaneous anastomosis of combined revascularization donor vessels in adults by duplex ultrasonography

Objective: To evaluate the preoperative diagnostic value of duplex ultrasonography in moyamoya spontaneous anastomosis of combined revascularization donor vessels in adults. Methods: A total of 99 preoperative adult patients who underwent superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis were retrospectively analyzed. Each side of the cerebral hemisphere was examined as a separate procedure. A total of 198 cerebral hemispheres were divided into three groups: a collateral, non-collateral, and control group based on digital subtraction angiography (DSA). Hemodynamic parameters, including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were analyzed. Results: There were only four of cases (5%, 4/198) of STA spontaneous anastomosis, whereas those of maxillary artery (MA) anastomosis were 44 (23.7%, 44/186). Compared with the control group, MA PSV and EDV of the collateral group increased significantly, while RI decreased significantly (p < .05). The area under the curve (AUC) of MA RI was 0.654. As a predictor of MA spontaneous anastomosis, duplex ultrasonography had high specificity but poor sensitivity. In collateral group, PSV and EDV detected two weeks post-surgery were significantly higher than those detected pre-operatively (PSV: p = .018, EDV: p = .025). By contrast, there were no significant difference of the PSV and EDV detected six months post-surgery compared with pre-operation (PSV: p = .450, EDV: p = .099). Additionally, MA RI in two weeks after the surgery was comparable with preoperative values. Conclusions: Duplex ultrasonography could be applied to evaluate the adult moyamoya spontaneous anastomoses of MA preoperatively. Despite its poor sensitivity, this diagnostic modality is still reliable and specific. STA-MCA anastomosis combined with EDMS did not affect MA pre-operative spontaneous anastomosis.