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.

Effect of wavelength and beam width on penetration in light-tissue interaction using computational methods.

Penetration depth of ultraviolet, visible light and infrared radiation in biological tissue has not previously been adequately measured. Risk assessment of typical intense pulsed light and laser intensities, spectral characteristics and the subsequent chemical, physiological and psychological effects of such outputs on vital organs as consequence of inappropriate output use are examined. This technical note focuses on wavelength, illumination geometry and skin tone and their effect on the energy density (fluence) distribution within tissue.

Lasers and intense pulsed light (IPL) association with cancerous lesions.

The development and use of light and lasers for medical and cosmetic procedures has increased exponentially over the past decade. This review article focuses on the incidence of reported cases of skin cancer post laser or IPL treatment. The existing evidence base of over 25 years of laser and IPL use to date has not raised any concerns regarding its long-term safety with only a few anecdotal cases of melanoma post treatment over two decades of use; therefore, there is no evidence to suggest that there is a credible cancer risk.

A randomized controlled study for the treatment of acne vulgaris using high-intensity 414 nm solid state diode arrays.

The treatment of acne vulgaris poses a challenge to the dermatologist, and the disease causes emotional anxiety for the patient. The treatment of acne vulgaris may be well-suited to home-use applications, where sufferers may be too embarrassed to seek medical treatment. This randomized controlled study is designed to quantify the effectiveness of using a blue light device in a therapy combined with proprietary creams, in the investigation of a self-treatment regimen.

Pigmentation: selective photothermolysis or non-specific skin necrosis using different intense pulsed light systems?

Background And Objective: This study considers end point tissue responses and side effects to determine whether 'square pulse' IPL is more or less effective than the traditional IPL. Supporting histological data and computational modelling results are provided. It provides guidance for IPL users unfamiliar with constant spectrum IPL devices and redirects attention to treatment end points.

Mathematical modeling of the optimum pulse structure for safe and effective photo epilation using broadband pulsed light.

The objective of this work is the investigation of intense pulsed light (IPL) photoepilation using Monte Carlo simulation to model the effect of the output dosimetry with millisecond exposure used by typical commercial IPL systems. The temporal pulse shape is an important parameter, which may affect the biological tissue response in terms of efficacy and adverse reactions. This study investigates the effect that IPL pulse structures, namely free discharge, square pulse, close, and spaced pulse stacking, has on hair removal.

Are home-use intense pulsed light (IPL) devices safe?

The domestic market for home-use hair removal devices is rapidly expanding and there are numerous intense pulsed light (IPL) products now available globally to consumers. Technological challenges for the design of such devices include the need to be cost-effective in mass production, easy to use without training, and most importantly, clinically effective while being eye-safe. However inexpensively these light-based systems are produced, they are designed to cause biological damage to follicular structures, so precautions to prevent both ocular and epidermal damage must be considered.

Measurement of home-use laser and intense pulsed light systems for hair removal: preliminary report.

Background: Laser and intense pulsed light (IPL) devices are used routinely by healthcare professionals for hair removal, but laser and light technology devices intended for home use have so far had little impact in the consumer market. However, as multinational companies enter this market, there will be an explosion in the use of such devices by the consumer.

Objectives: This investigation focuses on the technical performance of the devices tested and although no clinical data are presented, the measured parameters are those that will directly impact efficacy in hair reduction, efficient coverage of skin, and safety in terms of unintentional eye exposure to the light source or incorrect settings for a given skin type.

Relevance of the structure of time-resolved spectral output to light-tissue interaction using intense pulsed light (IPL).

Background And Objectives: High quality IPLs can offer simple, safe and effective treatments for long-term hair removal, removal of benign vascular and pigmented skin abnormalities, skin rejuvenation and acne treatments. Significant differences in clinical outcome have been recorded among different free-discharge and constant current IPLs despite identical settings. We investigated the differences in optical output of 19 IPLs in normal clinical use in the UK to evaluate spectral output, energy density values and pulse structure and propose a correlation between light-tissue interaction and spectral output as measured by time-resolved photo-spectrometry.

Measuring key parameters of intense pulsed light (IPL) devices.

Background: Unlike medical lasers, intense pulsed light (IPL) devices are largely unregulated and unclassified as to degree of safety hazard. With the exception of most of the USA, the United Kingdom and parts of Europe, the Far East and Australia, the sale of IPLs is generally unrestricted, with the majority being sold into the beauty therapy and spa markets. Standards are only imposed on manufacturers for technical performance data and operating tolerances determined by CE-compliance under electrical safety standards or the EU Medical Device Directive.