Volumetric changes of transferred free anterolateral thigh flaps in head and neck lesions

Abstract

ObjectiveThe purpose of this study was to clarify sequential volumetric changes of anterolateral thigh (ALT) flaps transferred to head and neck lesions. Patients and methodsWe retrospectively analyzed volumetric changes in fat and muscle of 22 ALT flaps. We assessed “true” flap volume using the water-displacement method intraoperatively. Postoperative flap volume was assessed using three-dimensional volume-calculating software. ResultsThe average duration until the entire flap volume decreased to its minimal size was 8.7 months. After 8.7 months, entire flap volume decreased to 47.4% of its initial intraoperative volume. The fat volume decreased to 62.5%, and the muscle volume decreased to 30.2%. The rate of muscle volume decrease was significantly larger than that of fat volume decrease (p<0.005). The only significant factor which affected entire flap volume decrease was the recipient site where the ALT flap was transferred (oral and pharyngeal lesions) (p=0.001), and the factor that affected fat volume decrease was postoperative body-weight loss (p=0.046). ConclusionTo minimize the influence of postoperative ALT flap volume decrease, an ALT flap should mainly comprise fatty tissue, and its size should be 1.6-times larger (100/62.5) than the ideal volume intraoperatively. Maintaining the body weight is crucial to avoid ALT flap volume decrease.