Pure Skin Perforator Flaps: The Anatomical Vascularity of the Superthin Flap

Background: Recently, a superthin "pure skin perforator" flap without any subcutaneous tissue was proposed, but the vascularity is still unclear. The authors therefore investigated the vascularity of the proposed superficial circumflex iliac artery-pure skin perforator along with its clinical applications and findings on indocyanine green imaging. Methods: The locations and dimension of 70 pure skin perforators on 40 flaps were investigated and classified into central-peripheral and mediolateral parts. Indocyanine green angiography was used to analyze the patterns of the vascular anatomy. Results: Twenty-seven of 29 cases (93.1 percent) presented with pure skin perforator vessels within the area 5 cm above and 1 cm below the inguinal ligament and 4 cm medial and 2 cm lateral from the anterior superior iliac spine. The total flap size averaged 39 +/- 22 cm(2) (range, 3 to 90 cm(2)). A subanalysis of the relationship between the flap size and location of pure skin perforators within the single, double, and triple pure skin perforator flap subgroups did not reveal any significance. Indocyanine green angiography revealed three interesting perfusion patterns of pure skin perforator flap: a radial diffusion pattern, direct linking vessels in the intradermal layer, and intradermal arteriovenous shunts. Conclusions: The location number of the pure skin perforators within the flap was not considered to be a crucial factor in the flap design and size in this study. This new knowledge regarding the pure skin perforator concept will allow surgeons to elevate a full-thickness skin flap safely.