Retroauricular Reconstruction and Sulcus Restoration of a Near-Total-Full-Thickness Postexcisional Defect Using a Folded Croissant-like Type IV KPIF (Keystone Perforator Island Flap)

Nonmelanoma skin cancers are the most frequent skin neoplasias occurring on the face. Surgical excision of these tumors results in significant soft tissue defects. The ear, especially the postauricular surface, represents a challenging area due to the paucity of reconstructive options (skin grafts or local flaps comprise the usual reconstructive options for such soft tissue defects after the excision of local tumors). We present the Keystone island perforator flap as a single-stage immediate reconstructive option addressing soft tissue defects in the posterior surface of the ear following skin cancer excision. The proximal part of the flap can be undermined, elevated, adding a third dimension, transposed, and extended to cover the soft tissue area until the rim of the helix, with very satisfactory functional and cosmetic results for the patient, maintaining the normal posterior ear-head sulcus. The keystone island perforator flap from the retroauricular skin is a reliable option for covering soft tissue defects of the postauricular surface owing to its robust vascularity, skin color matching, and minimal donor-site morbidity. The case of a 36-year-old female patient with a skin lesion on the posterior surface of the right ear measuring 3.0 cm×2.5 cm is presented, and a detailed description of the surgical procedure employed for reconstruction of the postauricular defect is provided. Treatment included the surgical excision of the lesion in the retroauricular area and immediate reconstruction of the subsequent defect using the Keystone perforator island flap from the retroauricular tissue of the mastoid area.