Keystone design perforator island flap in facial defect reconstruction

Facial defect coverage is a common subject in the field of reconstructive surgery. There are many methods for facial defect reconstruction, and reconstructive surgeons should choose the most appropriate method on a case-by-case basis to achieve both functional and aesthetic improvement. Among various options for facial reconstruction, the local flap technique is considered the best reconstructive modality to provide good tissue matches of color and texture, which is consistent with the ideal goal of reconstruction (replacement of like-with-like). Keystone design perforator island flap (KDPIF), devised by Behan in 2003, has been applied to various fields of reconstructive surgery in the past decade due to its design simplicity, robust vascular supply, and reproducibility. Several studies have reported KDPIF reconstruction of facial defects, such as large parotid defects, small-to-moderate nasal defects, and eyelid defects. However, KDPIF has been used relatively less in facial defects than in other body regions, such as the trunk and extremities. The purpose of this review is to provide an organized overview of facial KDPIF reconstruction including the classification of KDPIF, modifications, physiology, mechanism of flap movement, consideration of facial relaxed skin tension lines and aesthetics, surgical techniques, clinical applications, and precautions for successful execution of KDPIF reconstruction.