Guidelines for laser hair removal

Requests for removal of unwanted body hair are common in dermatologic and surgical practices. Technology continues to improve the achievement of a more permanent reduction through the use of lasers. Despite the increased use of lasers, to date, few guidelines exist in terms of how to approach laser hair removal. Specifically, one must understand the mechanism of hair growth and how lasers work to target the hair follicle. There is significant variation among practitioners in pre‐and post‐laser recommendations to patients as well as intervals between treatment sessions. We performed a thorough review of the literature in order to determine evidence for the ideal interval between treatment sessions and the ideal number of sessions. We also sought to establish, based on published reports, the recommendations for shaving, plucking, waxing or other hair removal methods prior to laser hair removal and the guidelines for sun exposure before and after laser treatments. Finally, we searched the literature to find out whether there are areas that should not be treated with laser hair removal. The evidence and recommendations in this article aim to help guide practitioners in their approach to laser hair removal.     

深肤色人种的激光脱毛

当今激光技术飞速发展，提高了激光脱毛的临床疗效，并使我们增加了对毛发生理及激光-组织相互作用的认识。配有冷却装置的长脉宽、长波长激光的应用，使得激光脱毛能够安全有效地应用于深肤色人种（皮肤Ⅳ～Ⅵ型）。目前主要用于深肤色人种脱毛的光源有长脉宽翠绿宝石（755nm）、长脉宽半导体（800nm）、长脉宽Nd：YAG（1064nm）激光和强脉冲光（590．1200nm）。但其中长脉宽Nd：YAG激光在深肤色人种脱毛中更为安全。     

激光脱毛的临床应用

体毛过多是一种常见的美学问题,传统脱毛方法的共同缺点是难以破坏毛母质和毛囊干细胞,故只能达到暂时性脱毛的效果。激光脱毛技术基于选择性光热动力学原理,可选择性地被毛囊内黑素颗粒吸收,产生光热效应,将毛球及毛囊干细胞彻底破坏,产生永久性脱毛,具有方便快捷,安全高效,效果永久性等特点。近年来激光脱毛仪器不断改良问世,受到了广大群众与皮肤科医师的深切关注。该文综述了激光脱毛技术的发展、作用原理、临床应用及相关影响因素。     

Guidelines for laser hair removal.

Requests for removal of unwanted body hair are common in dermatologic and surgical practices. Technology continues to improve the achievement of a more permanent reduction through the use of lasers. Despite the increased use of lasers, to date, few guidelines exist in terms of how to approach laser hair removal. Specifically, one must understand the mechanism of hair growth and how lasers work to target the hair follicle. There is significant variation among practitioners in pre-and post-laser recommendations to patients as well as intervals between treatment sessions. We performed a thorough review of the literature in order to determine evidence for the ideal interval between treatment sessions and the ideal number of sessions. We also sought to establish, based on published reports, the recommendations for shaving, plucking, waxing or other hair removal methods prior to laser hair removal and the guidelines for sun exposure before and after laser treatments. Finally, we searched the literature to find out whether there are areas that should not be treated with laser hair removal. The evidence and recommendations in this article aim to help guide practitioners in their approach to laser hair removal.     

Patient satisfaction with laser hair removal

Background Laser hair removal (LHR) is a widely used treatment for unwanted hair. Aim To determine patient satisfaction with LHR. Methods The clinic offered LHR by long pulse ruby, alexandrite and Nd:YAG. Patients attending the LHR clinic completed a patient satisfaction questionnaire. Satisfaction with LHR treatment was recorded on a linear analogue scale (LAS 0 = laser very much worse than alternative method; 10 = laser very much better than the alternative method). Results In terms of hair removal, 71% of patients were satisfied with their treatment. Laser treatment compared favourably with electrolysis and waxing. LHR scored 8.6 when compared with electrolysis and 7.7 when compared with waxing. During LHR treatments, 61% of patients used fewer ancillary methods than before. Most patients would recommend LHR to other persons with unwanted hair. Conclusions Most patients were satisfied with LHR.     

Blond hair removal using ELOS systems

Objective: The aim of this study was to test blond hair removal using the ELOS system, which is optical energy and radio‐frequency combined. Methods: Seventeen patients with blond hair were randomly selected from the Department of Lasertherapy, Medical Centre Maastricht, The Netherlands. The mean age of the patients was 57.4 years. The mean energy used per patient was 23.2?J/cm² and the mean radio‐frequency was 18.6?J/cm². Results: A mean hair reduction of 57.4% was obtained with a mean of 8.5 treatments. There was a trend found between hair removal and the number of treatments. No correlation was found between the percentage of hair removal and age. Furthermore, there was no correlation between hair removal and the device's technical data. No major side effects were observed postoperatively. Conclusions: This study showed that ELOS can effectively be used for blond hair reduction.     

Pili bigemini complicating diode laser hair removal

After two diode laser treatments for hair removal, a 39-year-old woman was noted to have pili bigemini within the treated areas. It resolved after a third treatment. Pili bigemini, the appearance of two hairs coming from the same follicular opening, can be induced by intermediate doses of laser energy. It follows sublethal damage to the hair follicule apparatus.     

Incidence of side effects after laser hair removal

BACKGROUND: Despite the widespread use of lasers for hair removal there are few data published on the incidence of side effects from this treatment. OBJECTIVE: The aim of this study was to generate data on a large number of patients receiving laser hair removal to obtain an accurate assessment of the incidence and type of side effects resulting from treatment. METHODS: A multicenter prospective study of patients presenting for laser hair removal was conducted to determine incidence of side effects in relation to skin type and laser or lasers used. RESULTS: Laser hair removal is associated with a low incidence of side effects that are self-limiting in the majority of cases. The highest incidence of side effects was seen in patients with darker skin treated with the long-pulsed ruby laser. CONCLUSIONS: Laser hair removal is inherently safe. For darker Fitzpatrick skin types the long-pulsed neodymium:yttrium-aluminum-garnet laser is preferred to the ruby laser.     

Blond hair removal using ELOS systems.

OBJECTIVE: The aim of this study was to test blond hair removal using the ELOS system, which is optical energy and radio-frequency combined. METHODS: Seventeen patients with blond hair were randomly selected from the Department of Lasertherapy, Medical Centre Maastricht, The Netherlands. The mean age of the patients was 57.4 years. The mean energy used per patient was 23.2 J/cm2 and the mean radio-frequency was 18.6 J/cm2. RESULTS: A mean hair reduction of 57.4% was obtained with a mean of 8.5 treatments. There was a trend found between hair removal and the number of treatments. No correlation was found between the percentage of hair removal and age. Furthermore, there was no correlation between hair removal and the device's technical data. No major side effects were observed postoperatively. CONCLUSIONS: This study showed that ELOS can effectively be used for blond hair reduction.     

Novel laser hair removal in all skin types

Background

Laser has been long accepted as a solution for excess or unwanted hair growth yet traditional lasers are not always ideal for safe and effective outcome for all skin types and hair characteristics. A diode laser module combining three wavelengths (755, 810, and 1064 nm) in a single pulse was developed to provide a fast and long-term solution for subjects with various profiles.

Aims

To evaluate the safety and efficacy of a Triple wavelength diode laser module for hair removal treatment in all skin types (Fitzpatrick I–VI).

Subjects and methods

This was a prospective, dual centered, single-arm study. Subjects were treated with a novel diode laser module. Thirty-six subjects were enrolled, sixteen with Fitzpatrick skin types I–IV (46%) and twenty with Fitzpatrick skin types V–VI (54%). Treatment areas were axilla and bikini lines. Subjects underwent 4 treatment sessions at 6 weeks ± 5 days intervals and attended a follow-up visit 3 months after the last treatment session. 2D digital photographs were taken at baseline and at the follow-up visit, and a hair count was conducted by three blinded evaluators.

Results

A significant reduction in hair count between baseline and the 3-month follow-up visit was observed in both axilla and bikini lines for all skin types. The mean hair reduction was 41.5 ± 19.4% and 48.1 ± 20.9% in the axilla and bikini line, respectively. A significant hair reduction was also observed within skin type groups; mean hair reduction 45.5 ± 16.9% and 40.3 ± 17.2% in skin types I–IV and V–VI, respectively, indicating similar efficacy for both light and dark skin types. No serious adverse events were reported.

Conclusions

This study demonstrates that the Soprano Titanium laser platform is safe and effective for hair removal treatment in all skin types.     

808 nm半导体激光脱毛的疗效分析

目的：评价808 nm半导体激光低能量多脉冲方式脱毛的疗效。方法：采用半导体激光脱毛仪对362例患者421个部位进行脱毛治疗（波长808 nm,脉宽100 ms,光斑直径10 mm×12 mm,能量密度11～15 J/cm2,频率5 HZ）,共5次。结果：腋部、下肢、上肢的1～5次治疗平均脱毛率分别达20%、30%、60%、70%和80%以上,唇部1～5次治疗平均脱毛率分别为15%,22%,31%,42%,51%。未见明显不良反应。结论：808 nm半导体激光脱毛安全有效。     

Pili bigemini and terminal hair growth induced by low-fluence alexandrite laser hair removal

BACKGROUND: Different types of lasers are used in the removal of undesirable hair by targeting the hair follicles, with the melanin pigment acting as the chromophore, and through the mechanism of selective photothermolysis. OBJECTIVES: This report documents an unusual increase in terminal hair growth after alexandrite laser hair removal in three female patients. CONCLUSION: Excessive hair growth after alexandrite laser hair removal must be listed as one of the complications resulting from the use of a laser with a fluence that is too low and can possibly be prevented if we use higher energy to fully destroy the hair follicles, with consideration given to the skin type and an effective cooling system.     

Long-term hair removal using a 3-millisecond alexandrite laser

BACKGROUND: Laser epilation is now used widely as a clinical alternative to electrolysis for the removal of unwanted hair. All of the laser systems presently being used produce a reliable temporary hair loss by inducing telogen. Most of the published studies use follow-up periods of 6 months or less after the last treatment and cannot address the issue of permanency. Since many patients desire permanent hair loss, there is a need for specific information on the exact benefits and limitations of each particular system. OBJECTIVE: The purpose of this study was to assess the degree of hair loss attained by a single treatment with a 3-msec alexandrite laser. A designated period for follow-up was used to address the issue of long-term benefits. METHODS: A single treatment was carried out on 25 study sites with a 3-msec alexandrite laser at 755 nm using fluences of 30 to 50 joules/cm(2). Hair counts were obtained manually by two independent observers marking terminal hairs under magnification. The counts were repeated using photographic images and the average of the four readings taken. The degree of hair loss was calculated at a time after treatment equal to one complete growth cycle for the particular anatomic site. A second measurement was obtained at a time equal to one growth cycle plus 6 months to determine whether any hair loss had remained stable. RESULTS: The average hair loss at the first follow-up time was 43%, with 60% of sites showing a hair loss of >30%. The hair loss remained stable and the reduction in hair density at both designated times was statistically significant (p <.05). CONCLUSION: A normal-mode alexandrite laser achieves a long-term alopecia and may result in a permanent loss of terminal hair after one treatment at fluences of 30 to 50 joules/cm(2).     

Paradoxical effects of hair removal systems: a review

Although a variety of lasers have proven to be clinically effective for long-term hair removal, the use of these lasers has also been associated with undesirable side effects, such as hyper- and hypopigmentation, crusting, erythema, and edema. One notable side effect that seems to be underreported in the literature is the growth of fine dark hair in untreated areas close to the treated ones. This contradictory hypertrichosis is known as the paradoxical effect. In this paper, we review the published reports of the paradoxical effect and offer some possible explanations for this effect. The paradoxical effect has been documented most commonly after the use of induced pulse light and alexandrite lasers. One possible explanation is the activation of dormant hair follicles by suboptimal fluences. Another mechanism may be the synchronization of hair growth cycles by direct light stimulation.     

A 12-month follow-up of hypopigmentation after laser hair removal

Abstract

Introduction: Laser hair removal is becoming an increasingly popular alternative to traditional methods such as shaving, waxing, among other methods. Semiconductor diode lasers are considered the most efficient light sources available and are especially well suited for clinical applications including hair reduction. The effectiveness of laser hair reduction depends on many variables, including the skin type of the patient. Material and Methods: A patient with Fitzpatrick Skin Type IV was submitted to laser hair removal of the arms with a high-power diode laser system with long pulses with a wavelength of 800 nm, a fluence of 40 J/cm² and a pulse width of 20 ms. A 12-month follow-up assessment was performed and included photography and questionnaire. Results: Hypopigmentation was observed after a single laser hair removal section. After 6 months with the area totally covered, a gradual suntan with a sun screen lotion with an SPF of 15 was prescribed by the dermatologist. After 12 months of the initial treatment, a complete recovery of the hypopigmentation was achieved. Conclusion: Although a safe procedure, lasers for hair removal may be associated with adverse side effects including undesired pigment alterations. Before starting a laser hair removal treatment, patients seeking the eradication of hair should be informed that temporary, and possibly permanent, pigmentary changes may occur.