Orbital volume augmentation after injection of human orbital adipose-derived stem cells in rabbits.

Abstract PURPOSE: This randomized, controlled animal study investigated the morphological and histological properties of rabbit orbital fat following injection of human orbital adipose-derived stem cells (hoADSCs). METHODS: The efficacy of hoADSCs was compared with that of hyaluronic acid gel (HAG) and human orbital stromal vascular fraction (hoSVF). Thirty orbits from 15 New Zealand white rabbits (25 weeks postnatal, 2500-3000 g) were injected with HAG (MW 1,000,000, 0.5 ml) (n = 10), hoSVF (0.25 ml) mixed with HAG (0.25 ml) (n = 10), or hoADSCs (0.25 ml) mixed with HAG (0.25 ml) (n = 10). The degree of proptosis and the time course of changes were determined and compared among groups. RESULTS: The difference between the initial value exophthalmometric value and that at 4 weeks after injection was 1.77 mm for HAG and 2.01 mm for hoSVF. The difference between the initial value and that at 12 weeks decreased to 0.05 mm for HAG and 0.24 mm for hoSVF. In contrast, injection of hoADSCs increased the exophthalmometric value by 2.43 mm at 4 weeks after injection, and this difference was maintained at 2.56 mm at 12 weeks. Histopathological examination revealed specific inflammation around the injection materials at 4 weeks after injection, and inflammation subsided 8 weeks after injection in all three groups. CONCLUSIONS: Thus, transplantation of hoADSCs with HAG is a safe and effective technique for orbital fat volume expansion. This is a new and promising method for orbital reconstruction and aesthetic orbital volume augmentation.