Annesofie Faurschou

Lasers or light sources for treating port‐wine stains

BACKGROUNDnPort-wine stains are birthmarks caused by malformations of blood vessels in the skin. Port-wine stains manifest themselves in infancy as a flat, red mark and do not regress spontaneously but may, if untreated, become darker and thicker in adult life. The profusion of various lasers and light sources makes it difficult to decide which equipment is the best for treating port-wine stains.nnnOBJECTIVESnTo study participant satisfaction, clinical efficacy, and adverse effects of the treatment of port-wine stains by lasers and light sources.nnnSEARCH METHODSnWe searched the following databases up to April 2010: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (Clinical Trials) in The Cochrane Library, MEDLINE (from 2005), EMBASE (from 2007), LILACS (Latin American and Caribbean Health Science Information database, from 1982), and reference lists of articles. We also searched online trials registries for ongoing trials and contacted trial authors where appropriate.nnnSELECTION CRITERIAnRandomised clinical trials (RCTs) of lasers or light sources for the treatment of port-wine stains.nnnDATA COLLECTION AND ANALYSISnOur outcomes of interest were participant satisfaction, reduction in redness of the port-wine stain as determined by clinical evaluation, and short- and long-term adverse effects of the treatments. Three authors independently extracted data and assessed trial quality.nnnMAIN RESULTSnWe included 5 RCTs involving a total of 103 participants; all of the trials used a within-participant design. The interventions and outcomes were too varied to be combined statistically. All trials used the pulsed dye laser for comparisons.None of the studies focused on participant satisfaction, which was one of our primary outcomes, but participant preference was evaluated in three of five studies. Participants preferred the pulsed dye laser to intense pulsed light based on the clinical effect. They marginally preferred the Neodymium:YAG (yttrium-aluminium-garnet) (Nd:YAG) laser to the pulsed dye laser due to shorter lasting purpura, and pulsed dye laser in conjunction with cooling was preferred to treatment with pulsed dye laser alone.All trials examined short-term efficacy of less than six months after treatments with the pulsed dye laser, intense pulsed light, and Nd:YAG laser. The pulsed dye laser was evaluated in all five trials. Depending upon the setting of the pulsed dye laser, this resulted in more than 25% reduction in redness. This was after 1 to 3 treatments for up to 4 to 6 months postoperatively in 50% to 100% of the participants. There was only one study each of intense pulsed light and Nd:YAG laser.Two trials had no occurrence of long-term adverse effects, i.e. six months after treatment. Three trials reported pigmentary alterations in 3% to 24% of the participants, with the highest percentage occurring in Chinese participants with darker skin types. In one study one participant experienced scarring of the skin caused by a too-high dose of the laser used. Short-term side-effects included pain, crusting, and blistering in the first two weeks after treatment.nnnAUTHORS CONCLUSIONSnThe pulsed dye laser leads to clinically relevant clearance of port-wine stains. A limited number of RCTs evaluated the efficacy from intense pulsed light and other laser types. High-quality RCTs are needed to assess individual efficacy from different lasers and light sources, as well as participant satisfaction.

Sun protection factor persistence during a day with physical activity and bathing

Background/purpose: The persistence of sunscreens during a day with physical activity and bathing is often debated. We wished to examine the durability of the protection achieved by one sunscreen application.

Ecological analysis of the relation between sunbeds and skin cancer.

Background/purpose: Previous studies implicate sunbeds in skin cancer aetiology. Women use sunbeds considerably more than men and the relation between sunbed use and skin cancer formation may therefore be explored as a sex difference. This presupposes that the sunbathing habits and the distribution of sun vacations among men and women have not changed over the last decades.

Squamous cell carcinoma induced by ultraviolet radiation originates from cells of the hair follicle in mice

Abstract:u2002 Short‐wave ultraviolet radiation (UVB) is the most carcinogenic part of the ultraviolet spectrum. The target cells of skin cancer are believed to be the bulge stem cells and/or their offspring, the transit‐amplifying cells that reside in the epidermis. However, the amount of UVB penetrating epidermis and reaching the bulge cells is very low, which questions if these cells suffer sufficient DNA damage to transform into cancer stem cells. We performed this study to determine whether UV‐induced squamous cell carcinoma (SCC) originates from the epidermis or the hair follicles in mice. Hairless mice had their epidermis removed at different levels using CO2 laser ablation. Simulated solar irradiations were administered either preoperatively (in total 7u2003weeks) or pre‐ and postoperatively (in total 30u2003weeks). Control groups were untreated or treated only with solar‐simulated radiation or with laser. Blinded clinical assessments of skin tumors were carried out weekly during 12u2003months observation. Only mice irradiated with solar‐simulated radiation both pre‐ and postoperatively developed tumors. Median time to first, second and third tumor ranged from 19 to 20.5u2003weeks and was not significantly different between the non‐laser and laser‐treated groups (Pu2003>u20030.05). The tumor response was thus similar in UV‐exposed mice whether they had their epidermis removed or not. No tumors appeared in control groups. Hence, UV‐induced SCC of mice originates from cells of the hair follicle, presumably the bulge stem cells, indicating that ultraviolet radiation penetrates epidermis sufficiently to cause irreversible DNA damage in cells located beneath the epidermis.

Epidermal Stem Cells - Role in Normal, Wounded and Pathological Psoriatic and Cancer Skin

In this review we focus on epidermal stem cells in the normal regeneration of the skin as well as in wounded and psoriatic skin. Furthermore, we discuss current data supporting the idea of cancer stem cells in the pathogenesis of skin carcinoma and malignant melanoma. Epidermal stem cells present in the basal layer of the interfollicular epidermis and in the bulge region of the hair follicle play a critical role for normal tissue maintenance. In wound healing, multipotent epidermal stem cells contribute to re-epithelization. It is possible that defects in growth control of either epidermal stem cells or transit amplifying cells constitute a primary pathogenetic factor in the epidermal hyperproliferation seen in psoriasis. In cutaneous malignancies mounting evidence supports a stem cell origin in skin carcinoma and malignant melanoma and a possible existence of cancer stem cells.

Treatment of multiple warts in a renal transplant recipient with decreased laser doses after application of a light absorbing dye

Background/Purpose: Multiple warts are a tremendous problem in immunosuppressed patients. Standard treatment has low efficacy and is often painful. We examined a new treatment combination of gentian violet and dye‐laser.

A randomized side-by-side study comparing alexandrite laser at different pulse durations for port wine stains.

Pulsed dye laser (PDL) represents the gold‐standard treatment for port wine stains (PWS). However, approximately 20% of patients are poor responders and yield unsatisfactory end‐results. The Alexandrite (Alex) laser may be a therapeutic alternative for selected PWS subgroups, but optimal laser parameters are not known. The aim of this study was to assess clinical PWS clearance and safety of Alex laser at a range of pulse durations.

Second-degree burns caused by exposure to sunbed with displaced filter in the facial tanner: a report of two cases

Sunbed exposure frequently leads to erythema of the skin but second‐degree burns are unusual. We report two patients who experienced second‐degree burns due to partial displacement of the filter in the facial tanner of a sunbed. This is a severe fault and calls for increased safety regulations.

Transepidermal water loss after photodynamic therapy, UVB radiation and topical corticosteroid is independent of inflammation

Background/purpose: Photodynamic therapy (PDT) and ultraviolet radiation cause an inflammatory reaction of the skin. This may lead to disruption of the skin barrier function. We examined the acute effect of PDT and short‐wave ultraviolet radiation (UVB) on the barrier function of the epidermis. Furthermore, we explored the effect on the skin barrier of topical corticosteroid previous to UVB exposure.