The value of indocyanine green-FLOW800 in microvasculature for predicting cerebral hyperperfusion syndrome in moyamoya disease patients

Among the notable complications of direct hemodynamic reconstruction for moyamoya disease (MMD) is cerebral hyperperfusion syndrome (CHS). In this study, we evaluated hemodynamic changes in small regional microvasculature (SRMV) around the anastomosis site by using indocyanine green (ICG)-FLOW800 video angiography and verified that it better predicted the onset of CHS. Intraoperative ICG-FLOW800 analysis was performed on 31 patients (36 cerebral hemispheres) with MMD who underwent superficial temporal artery-middle cerebral artery (MCA) bypass grafting at our institution. The regions of interest were established in the SRMV and thicker MCA around the anastomosis. Calculations were made for half-peak to time (TTP1/2), cerebral blood volume (CBV), and cerebral blood flow (CBF). According to the presence or absence of CHS after surgery, CHS and non-CHS groups of patients were separated. The results showed that Delta CBV and Delta CBF were substantially greater in SRMV than in MCA (p<0.001). Compared with the non-CHS group, Delta CBF and Delta CBV of SRMV and MCA were considerably greater in the CHS group (p<0.001). Delta CBF and Delta CBV on the ROC curve for both SRMV and MCA had high sensitivity and specificity (SRMV: Delta CBF, AUC=0.8586; Delta CBV, AUC=0.8158. MCA: Delta CBF, AUC=0.7993; Delta CBV, AUC=0.8684). ICG-FLOW800 video angiography verified the differential hemodynamic changes in the peri-anastomotic MCA and SRMV before and after bypass surgery in patients with MMD.