Preoperative perforator mapping of anterolateral thigh flaps using computed tomographic angiography and visual coordinate system for the reconstruction of head and neck defects.

OBJECTIVES: The anterolateral thigh (ALT) flap is a versatile workhorse flap for the reconstruction of head and neck defects; however, variations in the location of perforators are a significant concern. This prospective study proposes a rapid, effective, and convenient method for mapping the location of sizeable perforators on the curved thigh skin surface using the visual coordinate system in computed tomographic angiography (CTA) images. METHODS: Fourteen patients suffering from defects after head and neck carcinoma resection underwent CTA prior to ALT flap reconstruction at the Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, from January 2018 to August 2021. Using sterile gauze swab developing lines pasted on the patients' thighs, we established a coordinate system visualized both in CTA images and the thighs. The perforator information was then compared between the CTA and intraoperative findings. RESULTS: Twenty-one perforators were detected on CTA in the designed flaps, which were also confirmed during the operation with a visual pulse. The course and source of the perforators were consistent with the intraoperative findings. The distances of perforator coordinate points between CTA and intraoperative findings were <5 mm. Another five perforators (mostly without visual pulse) found intraoperatively could not be identified on preoperative CTA. Most flaps survived in their entirety, and one flap suffered a small area of necrosis due to perforator compression. CONCLUSION: This study demonstrated the efficacy of a novel perforator mapping method for anterolateral thigh flaps.