Abstract
INTRODUCTION: Autologous platelet-rich plasma (PRP), which is rich in growth factors, is widely used in aesthetic medicine to improve facial skin quality. However, its efficacy has been largely supported by subjective evaluations and case reports; objective and quantitative evidence remains limited. This study aimed to objectively and quantitatively evaluate the effects of PRP mesotherapy on facial skin quality, using a validated image analysis system. METHODS: Nine healthy adults (six females and three males; median age, 34 years) employed at the Tokyo Chuo Beauty Clinic were enrolled in this study. A split-face design was used, with PRP injected into the left hemiface and saline injected into the right hemiface under identical conditions (5 mL each). Facial images were obtained at baseline, two weeks, and one month using the NeoVoir system, which automatically identifies ten facial regions and extracts multiple quantitative skin parameters. The percentage change from baseline was compared between the sides. RESULTS: The primary endpoint, the gloss area at one month, showed a significantly greater increase on the PRP-treated side than on the saline-treated side (median difference, 16.3 %; p = 0.0039). At two weeks, the gloss also improved more on the PRP side, although the difference was not significant after false discovery rate (FDR) correction. Pore scores showed a greater reduction on the PRP side at one month (median difference, -17.6 %; p = 0.0039), but this result did not remain statistically significant after FDR adjustment (q = 0.0663). No significant differences were observed in wrinkle area, melanin content, or pigmentation indices. No serious adverse events occurred; only transient, mild local reactions such as redness and swelling were noted on both sides. CONCLUSION: This study provides novel objective evidence that PRP mesotherapy significantly improves facial gloss, a key feature of healthy young skin. An exploratory trend toward pore reduction was also observed, although mechanistic interpretations remain hypothesized owing to the absence of biophysical and structural measurements. Moving beyond subjective assessments, these findings support the potential of PRP for enhancing facial brightness, smoothness, and overall skin quality. Further studies with larger cohorts, extended follow-ups, and multimodal evaluations are warranted to validate and expand upon these preliminary results.