Objective: To investigate the clinical application of high-frequency color Doppler ultrasound (HFCDU) in detecting perforators in the deep adipose layers for harvesting super-thin anterolateral thigh flap (ALTF).
Methods: Between August 2019 and January 2023, 45 patients (46 sides) with skin and soft tissue defects in the foot and ankle were treated, including 29 males and 16 females, aged from 22 to 62 years, with an average of 46.7 years. The body mass index ranged from 19.6 to 36.2 kg/m 2, with an average of 23.62 kg/m 2. The causes of injury included traffic accident injury in 15 cases, heavy object crush injury in 20 cases, mechanical injury in 8 cases, heat crush injury in 1 case, and chronic infection in 1 case. There were 20 cases on the left side, 24 cases on the right side, and 1 case on both sides. After thorough debridement, the wound size ranged from 5 cm×4 cm to 17 cm×11 cm. All patients underwent free super-thin ALTF transplantation repair. HFCDU was used to detect the location of the perforators piercing the deep and superficial fascia, as well as the direction and branches of the perforators within the deep adipose layers before operation. According to the preoperative HFCDU findings, the dimensions of the super-thin ALTF ranged from 6 cm×4 cm to 18 cm×12 cm. The donor sites of the flaps were directly sutured.
Results: A total of 55 perforators were detected by HFCDU before operation, but 1 was not found during operation. During operation, a total of 56 perforators were found, and 2 perforators were not detected by HFCDU. The positive predictive value of HFCDU for identifying perforator vessels was 98.2%, and the sensitivity was 96.4%. Among the 54 perforators accurately located by HFCDU, the orientation of the perforators in the deep adipose layers was confirmed during operation. There were 21 perforators (38.9%) traveled laterally and inferiorly, 12 (22.2%) traveled medially and inferiorly, 14 (25.9%) traveled laterally and superiorly, 5 (9.3%) traveled medially and superiorly, and 2 (3.7%) ran almost vertically to the body surface. Among the 54 perforators accurately located by HFCDU, 35 were identified as type 1 perforators and 12 as type 2 perforators (HFCDU misidentified 7 type 2 perforators as type 1 perforators). The sensitivity of HFCDU in identifying type 1 perforators was 100%, with a positive predictive value of 83.3%. For type 2 perforators, the sensitivity was 63.2%, and the positive predictive value was 100%. The surgeries were successfully completed. The super-thin ALTF had a thickness ranging from 2 to 6 mm, with an average of 3.56 mm. All super-thin ALTF survived, however, 1 flap experienced a venous crisis at 1 day after operation, but it survived after emergency exploration and re-anastomosis of the veins; 1 flap developed venous crisis at 3 days after operation but survived after bleeding with several small incisions; 3 flaps had necrosis at the distal edge of the epidermis, which healed after undergoing dressing changes. All 45 patients were followed up 6-18 months (mean, 13.6 months). Three flaps required secondary defatting procedures, while the rest had the appropriate thickness, and the overall appearance was satisfactory.
Conclusion: Preoperative application of HFCDU to detect the perforator in the deep adipose layers can improve the success and safety of the procedure by facilitating the harvest of super-thin ALTF.
目的: 探讨高频彩色多普勒超声（high-frequency color Doppler ultrasound，HFCDU）术前探测深层脂肪内穿支在切取超薄股前外侧皮瓣（anterolateral thigh flap，ALTF）中的应用价值。.
方法: 2019年8月—2023年1月收治45例（46侧）足踝部皮肤软组织缺损患者，男29例，女16例；年龄22～62岁，平均46.7岁。身体质量指数19.6～36.2 kg/m 2，平均23.62 kg/m 2。致伤原因：交通事故伤15例，重物压砸伤20例，机械损伤8例，热压伤 1例，慢性感染1例。左侧20例，右侧24例，双侧1例。彻底清创后创面范围为5 cm×4 cm～17 cm×11 cm。均行游离超薄ALTF移植修复术。术前采用HFCDU探测穿支穿出深、浅筋膜的位置及深层脂肪内穿支走行方向和分支。根据术前HFCDU探测的结果，切取超薄ALTF范围为6 cm×4 cm～18 cm×12cm。供区直接拉拢缝合。.
结果: 术前HFCDU共定位55条穿支，其中1条未能在术中发现；术中共发现56条穿支，HFCDU漏报2条穿支。HFCDU定位穿支血管的阳性预测值为98.2%，灵敏度为96.4%。在HFCDU准确定位的54条穿支中，穿支在深层脂肪内的走行方向均在术中得到证实，即21条穿支（38.9%）向外下方走行，12条（22.2%）向内下方走行，14条（25.9%）向外上方走行，5条（9.3%）向内上方走行，2条（3.7%）近乎垂直走向体表。在HFCDU准确定位的54条穿支中，HFCDU准确识别了35条1型穿支和12条2型穿支（HFCDU将7条2型穿支误判为1型穿支），HFCDU识别1型穿支的灵敏度为100%、阳性预测值为83.3%，识别2型穿支的灵敏度为63.2%、阳性预测值为100%。患者手术均成功完成，超薄ALTF切取厚度为2～6 mm，平均3.56 mm。所有超薄ALTF均成活；1块皮瓣术后1 d发生静脉危象，急诊探查重新吻合静脉后成活；1块皮瓣术后3 d发生静脉危象，予以小切口放血后成活；3块皮瓣远端边缘表皮坏死，经换药后愈合。45例患者均获随访，随访时间6～18个月，平均13.6个月。3块皮瓣需行二期修薄，其余皮瓣厚薄合适，外观满意。.
结论: 术前利用HFCDU探测深层脂肪内穿支辅助切取超薄ALTF，能有效提高手术的成功率和安全性。.
Keywords: High-frequency color Doppler ultrasound; anterolateral thigh flap; perforator; super-thin flap.