Computed tomography angiography imaging for the chimeric anterolateral thigh flap in reconstruction of full thickness buccal defect

Background: Microvascular free flap transplantation is the current most common choice for reconstruction of difficult through-and-through buccal defect after cancer extirpation. The chimeric anterolateral thigh (ALT) flap is an ideal flap to cover this full thickness defect, but variation in the location of perforators is a major concern. Herein, we introduce computed tomographic angiography (CTA)-guided mathematical perforators mapping for chimeric ALT flap design and harvest. Methods: Between September 2008 and March 2009, nine patients with head and neck tumour underwent preoperative CTA perforator mapping before free ALT flap reconstruction of full thickness buccal defects. The perforators were marked on a 64-section multi-detector CT image for each patient, and the actual perforator locations were correlated with the intra-operative dissection. The donor limb of choice, either right or left, was also selected based on the dominant vascularity. Flap success rates, any associated morbidity and complications were recorded. Results: A total of 23 perforators were identified on CTA image preoperatively. Twenty-two of these perforators were chosen for chimeric flap design, and all were located as the CTA predicted, with the rate of utilization being 95.7% (22/23). There were two post-operative complications, including one partial flap necrosis and one microstomia. All of the ALT flaps survived, and there was no donor site morbidity. Conclusions: Preoperative CTA allows accurate perforator mapping and evaluation of the dominant vascularity. It helps the surgeon to get an ideal designing of the chimeric ALT flap with two skin paddles based on individual perforators, but only one vascular anastomosis in reconstruction of full thickness buccal defects.