Prediction of postoperative cerebral infarction after combined bypass surgery in adult moyamoya disease: combining quantitative parameters on RAPID perfusion CT with clinically related factors.

OBJECTIVE: The aim of this study was to identify predictive factors of postoperative cerebral infarction (PostCI) following combined bypass (CB) surgery in adult patients with moyamoya disease (MMD) using quantitative parameters from the rapid processing of perfusion and diffusion (RAPID) perfusion CT (PCT) software.

METHODS: The authors retrospectively reviewed 276 total hemispheres in patients with MMD who underwent CB. Preoperative volumes of time-to-maximum (Tmax) > 4 sec and > 6 sec were obtained from the RAPID analysis of PCT. These quantitative parameters, along with other clinical and angiographic factors, were statistically analyzed to determine the significant predictors for PostCI following CB.

RESULTS: PostCI occurred in 17 hemispheres (6.16%). PCA involvement (p = 0.016), and the volume of Tmax > 6 sec (p < 0.001) and Tmax > 4 sec (p < 0.001), were identified as variables related to PostCI in the univariable analysis. In the multivariable analysis, the volume of Tmax > 6 sec (OR 1.013, 95% confidence interval 1.007-1.019, p < 0.001) was determined to be an independent predictive factor significantly associated with PostCI after CB in adult patients with MMD. In the receiver operating characteristic (ROC) curve, the cutoff value of the preoperative volume of Tmax > 6 sec was determined to be 59.5 ml (sensitivity 82.4%, specificity 71.9%, area under the ROC curve 0.811).

CONCLUSIONS: For adult patients with MMD and a large volume of Tmax > 6 sec over 59.5 ml, more caution is required when deciding to undergo bypass surgery and in postoperative management.