Application of 3-D ultrasonography with a wide band linear matrix array volume transducer in preoperative localisation of perforating vessels of free anterolateral thigh perforator flap / 中华显微外科杂志

ABSTRACT

Objective:To investigate the application of 3-D ultrasonography enabled by a wide band linear matrix array volume transducer in the localisation of perforating vessels of a free anterolateral thigh perforator flap (ALTPF) before surgery, and to guide microsurgeons in precise design and harvest of a ALTPF.Methods:From May 2020 to October 2022, a retrospective study was carried out on 35 patients who had soft tissue defects and undertaken free ALTPF surgery in Department of Foot and Ankle Surgery, Wuxi No.9 People's Hospital Affiliated to Soochow University. ALTPFs were transfered for reconstruction of soft tissue defects of foot in 25 patients and of ankle in 10 patients. The age of patients were 20 to 66 years old. The defects were 11.0 cm×8.0 cm-28.0 cm×9.0 cm in size. The sizes of ALTPFs were at 12.0 cm×9.0 cm-29.0 cm×10.0 cm. Before surgery, ultrasound scans with a wide band linear matrix array volume transducer were performed to locate the perforating vessels. The 3-D ultrasound images showing the perforating vessels of ALTPFs were acquired and the number, location and classification of the perforating vessels were saved. After the appropriate perforating vessels had been determined, ALTPFs were designed for precisely intraoperative incision. The accuracy of preoperative location of perforating vessels by the linear matrix array volume ultrasound transducer was investigated in surgery. All patients received the scheduled postoperative follow-up at outpatient clinics.Results:Of the 72 perforating vessels discovered in surgery, 70 matched with those being located by ultrasound before surgery. It was found that a total of 67 perforating vessels located before surgery by ultrasonography were consistently mapped with the perforators discovered in surgery. Of the 67 consistently mapped perforating vessels, 19 were Kimura type I, 27 of Kimura type II and 21 of Kimura type III perforators. The rate of sensitivity and positive prediction were 95.7% and 93.1%, respectively, in the preoperative localisation of perforating vessels of ALTPFs with a wide band linear matrix array volume ultrasound transducer. Twenty-five ALTPFs were harvested subfascially and 10 superfascially. Average size of ALTPFs was 17.7 cm × 8.6 cm. The perforating vessels revealed during the harvest of all ALTPFs were basically consistent with the preoperative 3-D ultrasound. All flaps survived after surgery without any incident. The postoperative follow-up lasted 8 to 20 months, with 12.7 months in average.Conclusion:The 3-D ultrasonography with a wide band linear matrix array volume ultrasound transducer can accurately locate the perforating vessels of ALTPF before surgery. This technique has many advantages in the design and harvest of super-thin ALTPFs.