Split-leg comparison of low fluence diode laser and high fluence intense pulsed light in permanent hair reduction in skin types III to IV

Background/Objectives: All the standard light‐based techniques for permanent hair reduction, like laser and intense pulsed light (IPL) employ the highest tolerable fluence with a single pass. As opposed to standard techniques, a new diode laser technique employs low fluence with multiple passes. Here we evaluate and compare the efficacy, treatment time, comfort and safety of the low fluence multiple pass diode laser with high fluence single pass IPL for permanent hair reduction in Type III to IV Asian patients. Methods: Thirty Asian patients with Type III to IV black hair were enrolled and received three sessions of treatments at 6‐weekly to 8‐weekly intervals. A split‐leg study was performed in which the IPL was applied to one leg of each patient while the laser was applied to the other. The patients were followed up for 12 months. Results: All patients were satisfied with the results of the long‐term hair reduction without long‐term side effects. There was no statistically significant difference in hair reduction and treatment time between the laser (76.85%, 21.39 min) and the IPL (74.53%, 22.17 min) (P > 0.05). The visual analogue scale (VAS) pain score of the IPL (5.96) was higher than that of the laser (3.10) (P < 0.01). Conclusions: A series of high fluence single pass IPL and low fluence multiple pass diode laser treatments were performed with similar efficacy, speed and safety for permanent hair reduction. However, low fluence multiple pass diode laser treatment was less painful than high fluence single pass IPL.