Spectral Homeostasis - The Fundamental Requirement for an Ideal Sunscreen.

Sunscreen application to UV-exposed skin is promoted to prevent skin cancer and sun damage, within a comprehensive photoprotection strategy that also includes sun avoidance and wearing UV protective clothing. The benefits of sunscreen are verified in preventing sunburn but appear to be largely presumptive in skin cancer prevention. Contemporary science establishes UVA as a primary driver of melanoma and photoaging. Consequentially, the traditional UVB-skewed protection of sunscreens provides an intellectual and logical explanation for rising skin cancer rates and, in particular, their failure to protect against melanoma. Better protection could be achieved with more balanced UVB/UVA sunscreens, toward spectral homeostasis protection. Greater balanced protection has another advantage of attenuating fewer UVB rays, which aid synthesis of vitamin D and nitric oxide. Percutaneous absorption of Soluble Organic UV Filters leads to systemic exposure, which becomes the relevant safety consideration. It is minimized by selecting Insoluble UV Filters with low absorption potential from a molecular weight above 500 Da. The filters must also be very hydrophilic, very lipophilic, or consist of particles. The risk-benefit ratio is a medical imperative, more so for cosmetics or sunscreens, since in principle there should be no risk from their use. The production of ideal sunscreens that mimic the effective, balanced UVB/UVA attenuation of textiles and shade is now possible, while maintaining an acceptable therapeutic margin of safety in humans and a favorable ecologic profile. Sunscreens with a favorable risk-benefit ratio and good esthetic properties or other consumer-friendly attributes will improve compliance and may achieve substantial clinical benefits.

Pulsed dye laser double-pass treatment of patients with resistant capillary malformations.

The pulsed dye laser is an effective and established treatment for port-wine stains and has become the generally accepted standard of care. However, in many cases, complete clearance cannot be achieved as a significant proportion of lesions become resistant to treatment. Multiple passes or pulse-stacking techniques have been used to improve the extent and rate of fading, but concerns over increased adverse effects have limited this clinical approach. In this work, a double-pass technique with the pulsed dye laser has been described, which may allow for increased depth of vascular injury, greater efficacy, and an acceptable risk profile. Our aim was to determine the efficacy and the rate of side-effects for a double-pass protocol with a pulsed dye laser (PDL) to treat patients previously treated with PDL and/or other laser modalities. A retrospective chart review was conducted of 26 patients treated with a minimum of three double-pass treatments alone, or in combination, with single pass conventional PDL. Almost half of the patients (n = 12) showed either a moderate or significant improvement in fading compared to pre-treatment photographs with the double-pass technique. In a further 12 patients, there was a mild improvement. In two patients, there was no change. Sixteen patients developed mild side-effects: blisters (n = 5), dry scabs (n = 11) and transient hyperpigmentation (n = 4). This preliminary experience suggests that a double-pass technique at defined intervals between the first and second treatment with PDL can further lighten some port-wine stains, which are resistant to conventional single-pass treatments. This technique may be a useful addition to the laser treatment of PWS and deserves further scrutiny with randomized prospective studies and histological analysis to confirm the increased depth of vascular injury.

Effective epilation of white and blond hair using combined radiofrequency and optical energy.

OBJECTIVE: The present study examined the long-term photoepilatory effect on blond and white hair of a combined intense pulsed light (680-980 nm) device with a bipolar radiofrequency component producing electrical current at a depth of 4 mm. MATERIALS AND METHODS: Thirty-six adult women with white and blond hair (skin phenotypes I-V) were included in the study. The chin and upper lip were treated with four treatment sessions over 9-12 months with long-term follow-up performed at month 18 (6 months after the last treatment). The level of RF energy was 20 J/cm3, while optical fluences varied from 24 to 30 J/cm2. Hair counts and photographic evaluation of some sites were obtained at baseline, months 1, 3 and 5 and the final treatment session. RESULTS: An average hair removal of 48% was observed at month 18 (6 months following the final treatment session). A slightly higher photoepilatory efficiency was noted for blond hair (52%) versus white hair (44%) treatment sites. CONCLUSION: Combined radiofrequency and optical energy technology may produce effective photoepilation of blond and white hair phenotypes.