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Application of Computed Tomography Angiography Mapping and Located Template for Accurate Location of Perforator in Head and Neck Reconstruction with Anterolateral Thigh Perforator Flap

Background: The authors introduce a new method of preoperative computed tomography angiography mapping and virtual and printed located template for accurate location of perforators in the anterolateral thigh perforator flap for head and neck reconstruction. Methods: Between April and December of 2014, a cohort study was performed with 29 patients who underwent head and neck reconstruction with anterolateral thigh perforator flaps. Computed tomography angiography images were processed for maximum intensity projection and volume rendering to obtain and evaluate the perforator information. The virtual and printed templates with grid were used to transfer the perforator information for intraoperative guidance during flap harvest. The preoperative angiography results were compared with the high-frequency color Doppler results and with the intraoperative real-time findings to evaluate the accuracy of computed tomography angiography mapping. Results: The source vessel, origin, location, direction, number, and caliber of the perforators were determined by preoperative computed tomography angiography mapping. All of the perforator data were accurately mapped on a virtual template and printed on the located template to guide flap harvest. The flap was actually used and survived successfully in 20 patients. The results for perforators identified by mapping were more accurate than those for perforators identified by Doppler. There was no significant difference between the preoperative computed tomography angiography results and the intraoperative findings (p > 0.05). Conclusions: The role of preoperative computed tomography angiography mapping in guiding anterolateral thigh perforator flap harvest and reducing the unpredictable risk of surgery is acceptable. Located virtual and printed template with grid can transform preoperative computed tomography angiography information to the intraoperative setting accurately and easily. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.