Quantifiable clinical efficacy of injectable porcine collagen for the treatment of structural dark circles

BACKGROUND Dark circles are one of the most perplexing cosmetic problems for modern people. Nowadays, a new porcine collagen filler has been popular in China and many countries and has high safety. AIMS The purpose of this study is to explore and quantify the efficacy of this collagen filler in treating structured dark circles objectively and systematically. METHODS This is a prospective study. Twenty patients were included and took standard facial photographs at preoperative (Tp), immediately postoperative (T0), 1 week (T1), 2 weeks (T2), 4 weeks (T4), 8 weeks (T8), and 12 weeks (T12). The efficacy was quantified by measuring the depression of the tear trough and infraorbital melanin content. Three dermatologists blinded to the treatment were responsible for completing the subjective evaluations. RESULTS The depression volume, depression-affected area, and depression maximum depth of the tear trough decreased significantly immediately postoperation, and then all values increased slowly with time (P