Use of Intraoperative Fluorescent Indocyanine Green Angiography for Real-Time Vascular Evaluation of Pericranial Flaps

BACKGROUNDPericranial flaps (PCFs) have been widely used for skull base reconstruction. The key to successful skull base reconstruction using PCF depends on flap vascularity, but there have been no reports describing the real-time vascularity of PCF. In this study, we performed intraoperative fluorescent indocyanine green angiography to evaluate the real-time vascularity and viability of PCF and to estimate the reliability of this flap. METHODSEleven anteriorly based PCF (with a bilateral pedicle, ipsilateral pedicle, and random-pattern flap) and 11 laterally based PCF (with and without temporal muscle) were included in this study. The flap vascularity of each flap type considering the patientsʼ background was evaluated using indocyanine green angiography intraoperatively. RESULTSAnteriorly based PCF had significantly better vascularity compared to laterally based PCF. In anteriorly based PCF, there was no significant difference in vascularity between PCF with bilateral pedicles and an ipsilateral pedicle. In laterally based PCF, PCF without temporal muscle showed a wider vascular area compared to PCF with temporal muscle. As for the patient background, those older than 45 years, body mass index more than 25, and who were smokers tended to have lower vascularity. Preoperative radiation therapy did not show any significant differences in terms of flap vascularity. CONCLUSIONSAnteriorly based PCF had significantly better vascularity compared to laterally based PCF and seemed safer to harvest regardless of flap pedicle type. Also, the feasibility of harvesting muscle sparing laterally based PCF was indicated. Finally, being older than 45 years, a body mass index more than 25, or being a smoker might increase the risk of reducing flap vascularity.