Regional-Controlled Tissue Expanders Increase Skin Expansion and Thickness Compared to Standard Tissue Expanders in a Rat Model

Background: Skin and soft-tissue expansion are widely used. However, the existing methods cannot expand targeted areas on the top flap. Thus, the authors developed a new expander with a partially thickened top. The authors hypothesized that pressure differences would lead to higher growth near nonthickened regions and lower growth near thickened regions, allowing targeted expansion. Methods: Eighteen male Sprague Dawley rats (8 weeks old) were used; 20-ml rectangular regional-controlled expanders (n = 12) and ordinary expanders (n = 6) were implanted. Flaps on regional-controlled expanders were divided into nonthickened and thickened regions and tattooed. Discontinuous inflation began 14 days postoperatively, 3 ml every 3 days, until the volume reached 50 ml. Tattooed skin area and thickness were measured. Immunofluorescence staining detected cell proliferation (proliferating cell nuclear antigen–positive) and vascular density (CD31+). Growth factors (transforming growth factor-β, epidermal growth factor, vascular endothelial growth factor, and basic fibroblast growth factor) were assessed by enzyme-linked immunosorbent assay. Results: The expanded skin area of regional-controlled expansion nonthickened regions (396.2 ± 41.4 mm2) was 33.8 ± 10.0 percent larger than that of thickened regions (297.8 ± 38.9 mm2). Thickened regions had a 28.9 ± 14.6 percent thicker dermal layer (942.4 ± 55.5 µm) than nonthickened regions (737.1 ± 64.5 µm). Nonthickene...
Source: Plastic and Reconstructive Surgery - Category: Cosmetic Surgery Tags: Experimental Source Type: research