Extended lateral thoracic fasciocutaneous biosynthetic flap for reconstruction of full-thickness partial external ear defects: an experimental study

Abstract

External ear reconstruction is a controversial topic in reconstructive plastic surgery. Here, we prepared a pedicled biosynthetic flap for full-thickness, partial ear defects in rabbits. We operated on six adult female New Zealand rabbits weighing 3-4 kg. The dimensions of the lateral thoracic fasciocutaneous flap were 7 x 6 cm. The flap was elevated based on one of the bilaterally located internal thoracic arteries, which were dissected proximally. The pedicled flap was folded in two, and polypropylene mesh was sandwiched in the middle. The flap was adapted to a defect of 3.5 x 3 cm in diameter. In fact, the defect was created before elevation of the flap. Rabbits were followed up for 4 weeks, at the end of which they were killed and their ears were evaluated histopathologically. The survival rate of the rabbits was 100 %. All pedicled biosynthetic flaps were viable, but one showed partial (20 %) necrosis (1/6) and one was partially detached (1/6). Macroscopic (color, thickness, texture) and histological (polymorphonuclear leukocyte invasion in the skin, subcutaneous tissue, and at the junction between the polypropylene mesh and the flap) features of the flap were compared to the ipsilateral ear. A new technique was developed for partial external ear reconstruction with sufficient inner skeletal support and outer skin lining.