To assess the clinical value of high frequency color Doppler ultrasound combined with infrared thermography in the preoperative navigation of lobulated anterolateral thigh perforator flap transfer.

Thirty-seven patients who underwent free lobulated anterolateral thigh perforator flap transfer at Jinhua Hospital of Zhejiang University School of Medicine from January 2015 to December 2019 were examined by high-frequency color Doppler ultrasound and infrared thermography before operation. According to the intra-operative findings, the accuracy of high-frequency color Doppler ultrasound, infrared thermography, and their combination in detecting the effective perforators and the most active perforators was compared. The concordance rate between the flap designed by the use of both of the methods combined and the flap used in the surgery was assessed.

There were 99 effective perforators detected in 37 patients during operation. And 91 (91.9%), 90 (90.9%), and 98 (99.0%) perforators were detected by high-frequency color Doppler ultrasound, infrared thermography, and the two combined, respectively. High-frequency color Doppler ultrasound was more accurate than infrared thermography in detecting the effective anterolateral thigh perforators, but the difference was not statistically significant (P＞0.05). The two methods combined were more effectively than either of them alone, and the differences were statistically significant (χ²=4.193, P=0.017; χ²=5.164, P=0.009). For the detection of the most active perforators, infrared thermography failed to detect one case, with an accuracy rate of 97.3%. The accuracy rate of high-frequency color Doppler ultrasound was 100%. The lobulated flap designed based on the combination of the two methods was used in the surgery.

High frequency color ultrasound combined with infrared thermography can improve the detection of anterolateral thigh perforator vessels to provide a basis for the design of lobulated flaps.