Hair removal with a novel, low fluence, home-use intense pulsed light device

Assessment of adverse events for a home-use intense pulsed light hair removal device using postmarketing surveillance

BACKGROUND AND OBJECTIVES

Home-use intense pulsed light (IPL) hair removal devices are convenient for consumers. Consumer safety associated with home-use IPL devices, however, remains a subject of interest. In this descriptive analysis, we assessed the most commonly reported adverse events (AEs) for a home-use IPL device from postmarketing surveillance and qualitatively compared these with AEs from clinical studies and medical device reports of home-use IPL treatments.

MATERIALS AND METHODS

For this analysis of voluntary reports, we queried a distributor's postmarketing database for IPL devices for the period beginning January 1, 2016, to December 31, 2021. All sources of comments, for example, phone, e-mail, company-sponsored web sites, were included in the analysis. AE data were coded according to the Medical Dictionary for Regulatory Activities (MedDRA) terminology. Also, we conducted a PubMed search to identify AE profiles from existing literature on home-use IPL devices and we searched the Manufacturer and User Facility Device Experience (MAUDE) database for reports on home-use IPL devices. These results were qualitatively compared to the data in the postmarketing surveillance database.

RESULTS

A total of 1692 cases involving IPL were identified from voluntary reports of AEs between 2016 and 2021. The shipment-adjusted reporting rate for AE cases (number of AE cases/100,000 shipped IPL devices) was 67/100,000 during this 6-year period. The most commonly reported AEs were pain of skin 27.8% (470/1692), "thermal burn" 18.7% (316/1692), and erythema 16.0% (271/1692). Among the top 25 AEs reported, no unexpected health events were observed. The reported AEs were qualitatively similar to the pattern seen in clinical studies and the MAUDE database associated with such home-use IPL treatments.

CONCLUSION

This is the first such report documenting AEs for home-use IPL hair removal from a postmarketing surveillance program. These data are supportive of the safety of such home-use low-fluence IPL technology.

Home-based devices in dermatology: a systematic review of safety and efficacy

There is increasing demand for home-based devices for the treatment of dermatologic conditions and cosmesis. Commercially available devices include intense pulsed light, laser diodes, radiofrequency, light-emitting diodes, and ultraviolet B phototherapy. The objective of this report is to evaluate the current evidence regarding the efficacy and safety of home-based devices for the treatment of skin conditions. A systematic search of PubMed, Embase, and Cinahl was conducted on November 9, 2020 using PRISMA guidelines. Original research articles that investigated the efficacy and safety of home-based devices for dermatologic use were included. Bibliographies were screened for additional relevant articles. Strength of evidence was graded using the Oxford Centre for Evidence-Based Medicine guidelines. Clinical recommendations were then made based on the quality of the existing literature. After review, 37 clinical trials were included—19 were randomized controlled trials, 16 were case series, and 2 were non-randomized controlled trials. Ultimately, from our analysis, we recommend the home-based use of intense pulsed light for hair removal, laser diodes for androgenic alopecia, low power radiofrequency for rhytides and wrinkles, and light-emitting diodes for acne vulgaris. Trials investigating ultraviolet B phototherapy for psoriasis revealed mixed evidence for home treatments compared to clinic treatments. All devices had favorable safety profiles with few significant adverse events. Limitations to our review include a limited number of randomized controlled trials as well as a lack of data on the long-term efficacy and safety of each device.

Light-based home-use devices for hair removal: Why do they work and how effective they are?

OBJECTIVES

This review has the following objectives: Firstly, it provides an explanation of the evolution of laser/intense pulsed light (IPL) hair reduction modalities from high fluence professional devices to low fluence home-use appliances. Secondly, it summarises published literature reviews on home-use devices (HUDs) as evidence of their growing credibility. Thirdly, it proposes mechanistic differences in light delivery regimes and the resulting divergences in mode of action.

MATERIALS AND METHODS

An extensive literature search was performed to review the progress of laser/IPL-induced hair reduction and determine what evidence is available to explain the mode of action of professional and HUDs for hair removal. Establishing the likely biological mode of action of professional high-fluence systems versus home-use low-fluence appliances was performed by combining data obtained using ex vivo hair follicle (HF) organ culture and the clinical results involving human participants.

RESULTS

Significant basic science and clinical evidence has been published to confirm the clinical efficacy and technical safety of many laser and IPL home-use devices for hair removal. Clearly, HUDs are different compared to professional systems both in terms of fluence per pulse and in terms of biological mechanisms underlying hair removal. Here we presented data showing that a single low fluence pulse of both 810 nm laser (6.6 J/cm² , 16 ms) and IPL (9 J/cm² , 15 ms and 6.8 J/cm² , 1.9 ms) leads to induction of catagen transition. Catagen transition was characterized by morphological changes similar to what occurs in vivo with occasional detection of apoptosis in the dermal papilla and outer root sheath cells. This suggests that high hair reduction can be expected in vivo and longer-term treatment might result in HF miniaturization due to a cumulative effect on the dermal papilla and outer root sheath cells. In line with this hypothesis, in this review we demonstrate that long-term application of a commercially-available home-use IPL appliance resulted in persistent hair reduction (80%) one year after last treatment. These data are in line with what was previously reported in the literature, where clinical studies with home-use IPL appliances demonstrated high efficacy of hair reduction on female legs, armpits and bikini zones, with full hair regrowth after four treatments following cessation of IPL administration. Limitations of HUDs include lack of hair clearance for very dark skin types and low speed of treatment compared with professional devices. Numerous uncontrolled and controlled clinical efficacy studies and technical safety investigations on consumer-use appliances support many of the leading manufacturers' claims.

ANALYSIS & CONCLUSIONS

Manufacturers make consumer appliances safe and easy to use by considering "human factors," needs and capabilities of a variety of users. Safety is of primary concern to manufacturers, regulators and standards bodies as these appliances may be accessible to children or their use attempted on unsuitable skin types without full awareness of potential side effects. Consumer cosmetic appliances are provided with warnings and obvious safety notices describing the nature of any ocular or dermal hazard and precautions for reducing risk of accidental injury, infection, etc. HUDs employing optical energy are provided with design and engineering controls such as safety switches, alarms and sensors to prevent their incorrect operation or eye exposure. In-vivo studies demonstrated that low fluence home-use hair removal devices can result in high hair reduction efficacy after a short treatment regime, while prolonged and less frequent (once in six weeks) maintenance treatment over a year can lead to high and sustained hair reduction even one year after cessation of treatment. Home-use hair removal devices can be a useful adjunct to professional in-office treatments with high professional awareness. There are sufficient positive arguments for practitioners to make the case to patients for HUDs as "companion" products to professional treatments. In addition, devices for hair removal can be used effectively as stand-alone products by the consumer if they are willing to adopt a regime of regular or frequent use. Further clinical studies involving dynamic observation of HF cycle stage and type (terminal vs. vellus) over the total duration of treatment, for example, using biopsies or non-invasive imaging are necessary to confirm the proposed mode of action of low fluence pulses in a combination with treatment and maintenance regimes. Lasers Surg. Med. 51:481-490, 2019. © 2019 Wiley Periodicals, Inc.

Ultraviolet radiation after exposure to a low-fluence IPL home-use device: a randomized clinical trial

The prevailing advice is to avoid sun exposure after intense pulsed light (IPL) hair removal. However, no systematic evaluation of ultraviolet radiation (UVR) after IPL hair removal exits. Therefore, we investigated the occurrence of side effects in subjects receiving solar-simulated UVR after a low-fluence IPL treatment with a home-use device. Sixteen subjects with Fitzpatrick skin types (FST) II-V were enrolled. Three constitutive buttock blocks (4.4 × 6.4 cm) were each subdivided into four sites, randomized to one IPL exposure of 0, 7, 8, or 10 J/cm2 (spectral output 530-1100 nm). Blocks were randomized to no UVR or three standard erythema doses (SEDs) UVR either 30 min or 24 h after IPL. Follow-up visits were 48 h, 1 week, and 4 weeks after IPL. Outcome measures were (i) clinical skin reactions, (ii) reflectance measurements of erythema and pigmentation, and (iii) pain. Subjects with FST II-IV experienced no skin reactions up to 4 weeks after IPL, neither erythema, edema, blisters, crusting, textual, nor pigment changes. Reflectance confirmed no change in erythema and pigmentation (p ≥ 0.090). UVR exposure induced erythema and increased pigmentation. The combination of IPL and UVR induced skin reactions not different to responses from UVR (IPL-UVR vs. UVR, p ≥ 0.164). Pain was generally low (median 1, range 0-4) and correlated positively with fluence and pigmentation (Spearman's rho ≥ 0.394, p < 0.001). One subject with FST V experienced perifollicular hyperpigmentation after IPL and slightly more intense when exposed to UVR. A single UVR exposure of three SEDs either shortly or 1 day after low-fluence IPL causes no amplification of skin responses in constitutive skin of individuals with FST II-IV.

Quantitative assessment of growing hair counts, thickness and colour during and after treatments with a low-fluence, home-device laser: a randomized controlled trial

BACKGROUND

At-home laser and intense pulsed-light hair removal continues to grow in popularity and availability. A relatively limited body of evidence is available on the course of hair growth during and after low-fluence laser usage.

OBJECTIVES

To assess growing hair counts, thickness and colour quantitatively during and after cessation of low-fluence laser treatment.

METHODS

Thirty-six women with skin phototypes I-IV and light to dark-brown axillary hairs were included. Entire axillary regions were randomized to zero or eight self-administered weekly treatments with an 810-nm home-use laser at 5·0-6·4 J cm(-2). Standardized clinical photographs were taken before each treatment and up to 3 months after the final treatment for computer-aided quantification of growing hair counts, thickness and colour.

RESULTS

Thirty-two women completed the study protocol. During sustained treatment, there was a reduction in growing hair that reached a plateau of up to 59%, while remaining hairs became up to 38% thinner and 5% lighter (P < 0·001). The majority of subjects (77%) reported 'moderately' to 'much less hair' in treated than untreated axilla, and assessed remaining hairs as thinner and lighter (≥ 60%). After treatment cessation, hair growth gradually returned to baseline levels, and 3 months after the final treatment the count and thickness of actively growing hair exceeded pretreatment values by 29% and 7%, respectively (P ≤ 0·04).

CONCLUSIONS

Sustained usage of low-fluence laser induced a stable reduction of growing hair counts, thickness and colour. The reduction was reversible and hairs regrew beyond baseline values after cessation of usage. Computer-aided image analysis was qualified for quantification of hair counts, thickness and colour after laser epilation.

The role of natural and UV-induced skin pigmentation on low-fluence IPL-induced side effects: a randomized controlled trial

BACKGROUND AND OBJECTIVES

The risk of adverse skin effects following light-based hair removal is greater in pigmented skin based on the theory of selective photothermolysis. Thus sunlight-induced pigment i.e., facultative pigmentation, increases the risk of adverse skin effects, perhaps disproportionately. The aim of this study was to evaluate the influence of constitutive and facultative skin pigmentation on low-fluence intense pulsed light (IPL)-induced adverse skin effects.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-one subjects with Fitzpatrick skin type II-IV were enrolled. Two buttock blocks were randomized to receive 0 or 8 solar simulated ultraviolet radiation (UVR) exposures of consecutively increasing Standard Erythema Doses (2-4 SED). Each block was subdivided into four sites, randomized to receive IPL of 0, 7, 8, or 10 J/cm(2) , once a week for 3 weeks. Biopsies were taken 16-24 hours after the first IPL exposure and subjects were seen 1 and 4 weeks after the last IPL exposure. Outcome measures were: (i) skin reactions, (ii) pain, (iii) mRNA expression of pigment-markers microphthalmia-associated transcription factor (MITF) and pro-opiomelanocortin (POMC), and (iv) clinical appearance of biopsy wounds.

RESULTS

Skin pigmentation increased after UVR (baseline median 13.8%, after UVR 28.1%, P = 0.0001) in all skin types. Subjects reported low pain intensities (median 1.5, scale 0-10) and experienced transient erythema immediately after IPL exposure. No persistent erythema, blisters, crusting, textual, or pigment changes were observed. The risk of erythema and pain intensities increased with IPL dose and skin pigmentation (P < 0.03). There was no difference in pain or skin reactions in skin with similar degree of natural and facultative pigmentation (P ≥ 0.104). Expression of cellular pigment-markers was not influenced by IPL exposure, neither in constitutive nor in facultative pigmented skin. Clinical appearance of biopsy wounds was unaffected by IPL exposure.

CONCLUSION

The prevalence and intensity of low-fluence IPL-induced adverse skin effects depended on IPL dose and skin pigmentation regardless of the origin, i.e., constitutive versus UV induced.

Evaluation of a hot-wire hair removal device compared to razor shaving

BACKGROUND AND OBJECTIVES

We describe a blinded, controlled, prospective clinical study of a hot-wire device promoted for hair removal and the reduction or delay of hair regrowth (no!no!, Radiancy, Inc., Orangeburg, NY) compared to a shaving control.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-two subjects were treated by trained clinical staff with the hot-wire device according to its Instructions for Use on the lower leg two times per week for 8 weeks. An adjacent site was shaved with a razor blade on the same schedule to provide a control. Subjects were followed for 3 months after the last treatment to study the durability of the results. Standardized high-resolution photographs were made at baseline, once a week during treatment, and monthly during the post-treatment follow-up period. Micro-tattoos were used to ensure treatments and photographs were reliably made in the same anatomical location from visit to visit. Both active and control sites were shaved prior to baseline and allowed to regrow for a fixed period of time before first treatment to provide a consistent and well-defined baseline hair condition. Quantitative hair counts were made by a third party from the photographs and standard statistical analysis was performed to look for differences between the active and control sites. Visual assessments and quantitative analysis was also performed on the photographs to see if there were any differences in hair thickness (diameter) and hair color between the active and control sites.

RESULTS

The results show that shaving and the hot-wire device are indistinguishable in short-term or long-term effect, based on both visual assessment of the photographs and statistical analysis of the hair counts. The control (shaving) had a mean baseline hair count of 79.4, which remained stable (74.8-84.3) during the 8 week-treatment phase and climbed substantially after stopping treatment to 98.8, 100.1, and 104.6 at 1, 2, and 3 months post-treatment, respectively. The active (hot-wire device) had a mean baseline hair count of 86.0 which remained fairly stable (81.7-95.1) during the treatment phase and then climbed substantially after stopping treatment to 104.0, 106.4, and 109.0 at 1, 2, and 3 months post-treatment, respectively. The difference in hair counts between the control and shaving showed that (a) in the treatment phase, shaving was slightly more effective at hair removal than the hot-wire device with weak statistical significance (P < 0.05 at 5 of 7 time points) and (b) in the follow-up phase, shaving and the hot-wire device were statistically indistinguishable (P = 0.252, 0.0972, and 0.230 at 1, 2, and 3 months, respectively). Likewise, the difference in percentage change from baseline in hair counts (which normalizes to baseline values) between the shaving control and hot-wire device is close to zero at every time point (-4.9% to +4.9%) and the t-test P-values are high (0.154< P < 0.890 over all the time points in the study and 0.360 < P < 0.890 during the 1, 2, and 3 month follow-up period), indicating no detectable difference between shaving and the hot-wire. In terms of hair characteristics, no difference in hair color or hair thickness was seen between the shaving control and the hot-wire sites in the treatment or follow-up period.

CONCLUSIONS

Relative to shaving, the hot-wire (no!no!) device does not produce lessened hair density, decreased hair re-growth rate, greater duration of effect, nor induce changes in hair thickness and color. We conclude that the hot-wire device does not offer any benefit as compared to shaving.

Guidelines on the safety of light-based home-use hair removal devices from the European Society for Laser Dermatology

In the past 5 years since their US introduction, there has been a rapid proliferation of light-based hair removal devices intended for home-use. In the last 2 years in Europe, sales already run into many tens of thousands of units with well-known multi-national companies entering the market. These guidelines provide a definition of light-based home-use technology, to inform healthcare professionals about home-use light-based technology and encourage manufacturers wishing to sell in Europe to adopt 'best practice'. The review presents the current status on standards and regulation issues and considers home-use safety issues, encompassing human, device and electrical safety, given risks to the eyes and skin from optical radiation both to the consumer and persons in the vicinity. Proposed technical measurement methodology is considered with focus on recognized critical parameters for the safe use of light-based hair removal technology including recording the technical performance and safety claims of a range of home-use hair removal devices. The literature review emphasizes potential adverse incidents and safety aspects of treating cosmetic conditions, such as unwanted hair growth. Although some regulations exist, they differ from region to region and there is a specific need for international common principles and guidelines relating to the manufacture, marketing and use of intense pulsed light and laser devices, including manufacturing standards for home-use products intended, amongst others, for cosmetic hair removal and photo-rejuvenation procedures. In these guidelines, the European Society for Laser Dermatology (ESLD) provides a professional view of what 'best practice' may imply for manufacturers and consumers alike.