Hair Follicle Changes Following Intense Pulsed Light Axillary Hair Reduction: Histometrical, Histological, and Immunohistochemical Evaluation

The study, conducted on 21 female volunteers, demonstrated that intense pulsed light (IPL) treatment is effective in reducing axillary hair by inducing hair follicle miniaturization and prolonging the telogen phase. Significant decreases in hair count, hair shaft diameter, and the percentage of terminal anagen follicles were observed, along with reduced expression of proliferation markers PCNA and Ki67 and increased expression of the DNA damage marker P53. This suggests that IPL treatment decreases hair follicle proliferation and may promote apoptosis. The study also noted a significant reduction in hair growth, with hair reduction percentages of 89.26% at one week and 75.90% at one month post-treatment, although there was a slight increase in hair count after one month compared to one week post-treatment. Morphological changes in the hair follicle structures were not observed, indicating the absence of follicular necrosis and resorption.