Title: Long-term epilation with long-pulsed neodimium:YAG laser.
Authors: Bencini PL, Luci A, Galimberti M, Ferranti G
Journal: Dermatol Surg 1999 Mar;25(3):175-8
PMID: 10193962, UI: 99208305
Affiliated institution: Servizio di Dermatologia, Ospedale S. Raffaele, Milan, Italy.
BACKGROUND: Unwanted body hair can represent a severe cosmetic disturbance. The traditional methods used to epilate often have limitations, side effects, and unsatisfactory results. In recent years, various light sources (lasers and others) have been developed for long-term epilation of unwanted hair.
OBJECTIVE: This study evaluates, on a large number of patients, the efficiency and safety of a long-pulsed low-potency Nd-Yag laser invented specifically for long-term hair removal.
METHODS: Some 208 subjects needing epilation were divided into three groups and treated during an 11-month period. Group A included 79 patients with a normal distribution of unwanted hair; Group B 67 patients with constitutional hypertrichosis; and Group C 62 patients with hirsutism. Treatment sessions were performed with a fluence of 23-56 J/cm2 at 1-month intervals until obtaining desirable results. Follow-ups ranged from 1 to 6 months. In 3 patients 4-mm diameter punch biopsy specimens were obtained before the first session and again after 6 hours. A third biopsy was performed after 3 months.
RESULTS: Every session resulted in a 20-40% hair loss, depending on the color of hair. Complete epilation was obtained in 4 to 6 sessions. Only white hair was not receptive to laser light, and its growth was not modified. No patients, including dark-complexioned patients, had blistering, hypo-or hyperpigmentation. No pain was present during treatment except for the axillary area. In the specimen obtained after 6 hours, very extensive necrosis of the hair follicular and sebaceous gland epithelium was evident. Histologic findings of the biopsies taken after three months showed complete disappearance of hair and moderate fibrosis.
CONCLUSION: This study proves that the long-pulsed Nd:Yag laser treatment produces an excellent prolonged epilation with no relevant side effects. This laser light, having a 1064 nm wavelength, is minimally absorbed in superficial skin layers, and pronounced scattering up to 5 mm occurs targeting the deeper follicles.