ABSTRACT
First described by Song et al. in 1984, the anterolateral thigh (ALT) flap has become one of the most popular free flaps in head and neck reconstructive surgery. The ALT flap is a perforator flap, which means that it is based on a perforator vessel originating from an axial vessel, passing through various structural elements of the body besides interstitial connective tissue and fat before reaching the subcutaneous fat layer. A handheld Doppler may be useful to mark out the location of the perforators prior to skin incision. However, it has a positive predictive value of only 65%, therefore should only be used as a guide. Inability to locate a suitable Doppler signal must not be a reason to abandon the chosen leg for flap harvest. The patient should be positioned supine without any sandbags under the hip or splinting of the leg.
