Application of transcranial Doppler in the efficacy evaluation of encephalo-duro-arterio-synangiosis for moyamoya disease

Abstract

Objective To investigated the application value in the efficacy evaluation of transcranial Doppler (TCD) in encephalo-duro-arterio-synangiosis (EDAS) for moyamoya disease. Methods The patients with moyamoya disease treated with EDAS conducted digital subtraction angiography (DSA) and TCD examinations before procedure and at 6 months after procedure respectively. The pulsatility index (PI), resistance index (RI) and mean flow velocity (MFV) before and after the superficial temporal artery surgery were measured respectively. The correlation between the TCD parameter variation rate and DSA efficacy grading was evaluated. Using the receiver operator characteristic (ROC) curve to calculate the optimal cut-off value of the TCD parameters for predicting the operation efficacy. Results A total of 46 patients with moyamoya disease were enrolled, 40 patients were bilateral hemisphere involvement and 6 were unilateral involvement. A total of 86 hemispheres were treated with EDAS. According to the results of DSA reexaminations, the grades of efficacy were as follows: grade 0, 18 sides, grade 1, 37 sides, grade 2, 18 sides, and grade 3, 13 sides. When the DSA grade was 0, there were no significant differences in PI, RI and MFV before and after procedure, and there were significant differences in the postoperative change of other TCD parameters at all levels (all P<0.001). At 6 months after procedure, the change rates of PI, RI and MFV were-30.83%±21.71%, -19.64%±14.45% and 96.08%±100.76%, respectively, and they had good correlation with the results of DSA efficacy grading. Their Spearman correlation coefficients were -0.879, -0.891 and 0.715, respectively (all P<0.001). ROC curve analysis showed that the best cutoff values of the TCD parameter change rates for predicting good operative effect were as follows: PI decrease rate, 36% (area under the curve, 0.966; sensitivity, 0.968, specificity, 0.891; P<0.001), RI decrease rate, 27% (area under the curve, 0.973; sensitivity, 0.903, specificity, 0.946; P<0.001), and MFV increase rate, 111% (area under the curve, 0.879; sensitivity, 0.742, specificity, 0.927; P<0.001). Conclusions TCD can detect hemodynamic parameter changes of superficial temporal arteries after EDAS. It has higher application value in the long-term postoperative efficacy evaluation. Key words: Moyamoya Disease; Cerebral Revascularization; Cerebrovascular Circulation; Ultrasonography, Doppler, Transcranial; Treatment Outcome