Poly‑D,L‑lactic acid (PDLLA) scalp microinjection protocol with optional light microneedling priming for non‑scarring alopecia: A prospective pilot case series

This pilot case series investigated the effects of Poly-D,L-lactic acid (PDLLA) scalp microinjections on 20 patients with non-scarring alopecia, finding that 90% showed hair regrowth improvement by week 12, with results sustained at week 24. Optional microneedling was used in 14 patients to enhance PDLLA distribution. No serious adverse events were reported, suggesting good short-term tolerability. However, the study's preliminary findings are limited by its small sample size, lack of a control group, and subjective endpoints, indicating a need for further research with objective measures and extended follow-up to confirm PDLLA's efficacy and safety in hair regeneration.