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H Moseley

Publications and source records attributed to H Moseley.

At least 19 recordsLinked to original sources
PubMed2006

Clinical and research applications of photodynamic therapy in dermatology: experience of the Scottish PDT Centre.

BACKGROUND AND OBJECTIVES: The Scottish PDT Centre has carried out 3,442 treatments on 762 patients with superficial skin lesions, especially superficial basal cell carcinoma (sBCC), Bowen's disease (BD) and actinic keratosis (AK). STUDY DESIGN MATERIALS AND METHODS: The article reviews our experience of various light sources and associated dosimetry; thereafter we discuss clinical outcome followed by some of our research studies in clinically important areas. RESULTS: We show that improved dosimetry is required to ensure an optimal light dose is delivered to the tumour. We have shown that photosensitizers and proteins interact in such a way that their photophysical and photochemical properties are modified. We have also demonstrated the presence of DNA strand breaks with two different photosensitizers, but there is no evidence that PDT is significantly mutagenic in clinical practice. CONCLUSIONS: In our experience, topical PDT is generally well tolerated and is an effective treatment of sBCC, BD, AK, field change and lesions at sites of poor healing.

Aminolevulinic Acid↗
PubMed2006

Ambulatory photodynamic therapy: a new concept in delivering photodynamic therapy.

BACKGROUND: Photodynamic therapy (PDT) has been shown to be effective in treating Bowen's disease, superficial basal cell carcinoma and actinic keratosis. OBJECTIVES: To investigate the feasibility of delivering PDT using a portable light-emitting diode device. METHODS: A prototype diode array, comprising 37 AlGaInP diodes cast in epoxy with a diffuser, and driven by a battery pack, was designed and constructed. A pilot study was carried out in five patients with histologically proven Bowen's disease who were referred for PDT with 5-aminolaevulinic acid. They were all treated in the hospital-based dermatology PDT suite such that each received the same level of supervision as patients receiving PDT with nonambulatory light sources. Patients recorded pain levels. In accordance with our usual practice, patients received two treatments at a 4-week interval. RESULTS: Four of five patients were clear at follow-up (range 6-13 months, median 9). Pain was classified as none or mild in 80% of treatments and moderate in the remainder. CONCLUSIONS: There are many potential benefits of ambulatory PDT, including the possibility of a much higher patient throughput, and allowing effective treatment at home. This pilot study provides early promising data of the safety and efficacy of this approach.

Ambulatory Care↗
PubMed2006

Photopatch testing of 1155 patients: results of the U.K. multicentre photopatch study group.

BACKGROUND: Photoallergic contact dermatitis can be difficult to diagnose if not appropriately investigated. Currently, the most common U.K. photoallergens appear to be sunscreen chemicals. The investigation of choice is photopatch testing (PPT), which is probably underused. In part, this is due to differences in methodology and results interpretation. OBJECTIVES: To conduct PPT using a group of sunscreen chemicals, defined indications and a standardized methodology including interpretation and relevance of reactions in patients attending for investigation at 17 centres across the U.K., Ireland and the Netherlands. METHODS: Patients (n = 1155) who fulfilled the inclusion criteria were investigated with PPT using sunscreen chemicals in addition to suspected topical products. Readings were taken at 24, 48 and 72 h following standardized ultraviolet A irradiation (5 J cm(-2)). The clinical relevance of any reaction was recorded. RESULTS: Of the 1155, 130 had allergic reactions (11.3%). Of these, 51 had photoallergy (PA) (4.4%), 64 had contact allergy (CA) (5.5%), and 15 patients had combined PA and CA (1.3%). Multiple PA was seen in some. The most common photoallergen was benzophenone-3 (27 reactions; 21%). Most reactions (60%) were clinically relevant. The most common indication for testing in patients found to have PA was a history of reacting to a sunscreen (41%). The other 59% had an exposed-site dermatitis/skin problem or a photodermatosis. Some centres (n = 8) performed readings after the standard 48-h reading, and an extra 32 PA and 22 CA reactions were detected, which were not evident at 48 h. A new photoallergen (octyl triazone) was detected in two patients. CONCLUSIONS: Sunscreen PA and CA are probably equally uncommon. Most reactions, of both reaction types, were relevant clinically. A large proportion of patients (59%) found to have PA was unaware of reacting to a sunscreen chemical, suggesting that PA should be considered as an explanation in any exposed-site dermatitis. Although this study focused on reactions at 48 h postirradiation, readings performed up to 96 h, while inconvenient, add value by detecting additional relevant responses. A previously unknown photoallergen was found, highlighting the need for awareness of novel photoallergens in the marketplace. A standardized PPT method not only encourages more use of this investigation, but also facilitates comparison of results between centres and so will improve our understanding of PA.

Adolescent↗
PubMed2005

Photogenotoxicity of hypericin in HaCaT keratinocytes: implications for St. John's Wort supplements and high dose UVA-1 therapy.

Extract of St. John's Wort (Hypericum perforatum) is commonly used as natural remedy for treatment of mild to moderate depression. However, it contains a powerful photoactive component, hypericin, which can cause a severe photodermatitis when eaten by grazing animals (hypericism). In humans, there is evidence that supplementation with St. John's Wort can reduce the minimal erythemal dose (MED) in patients undergoing high dose UVA-1 phototherapy. This is a recent development in phototherapy where the most erythemogenic parts of the UVA spectrum are filtered out, allowing delivery of higher doses of the longer wavelengths of UVA. Although current published evidence suggests that the plasma levels of hypericin are unlikely to cause clinical phototoxicity, it has been established that photoactive compounds can cause DNA damage at sub-toxic and sub-erythemal doses, the effects of which might not be apparent for many years after the event. The present study used HaCaT keratinocytes to investigate the photoclastogenic ability of hypericin on irradiation with UVA. The results show that although the combination of hypericin and UVA light increased the genotoxic burden, when all factors are taken into account, the risk of significant photogenotoxic damage incurred by the combination of Hypericum extracts and UVA phototherapy may be low in the majority of individuals.

Anthracenes↗
PubMed2005

A randomized controlled comparison of the efficacy of Dead Sea salt balneophototherapy vs. narrowband ultraviolet B monotherapy for chronic plaque psoriasis.

BACKGROUND: Dead Sea (DS) salt solution soaks are used in combination with narrowband ultraviolet B (NB-UVB) to treat psoriasis in many centres, particularly in continental Europe. No previously published controlled study has assessed DS salt + NB-UVB balneophototherapy. OBJECTIVES: To compare DS salt balneophototherapy with NB-UVB monotherapy for chronic plaque psoriasis. METHODS: Sixty patients with chronic plaque psoriasis participated in this paired, controlled study, with pretreatment DS salt soaks randomly allocated to each participant's right or left study limb. Psoriasis severity was assessed with a Scaling, Erythema and Induration score by a blinded observer. Assessments were weekly during the therapy course, and thereafter 8-weekly until relapse or for up to 1 year after clearance. RESULTS: The mean area under the psoriasis severity-time curves during treatment was not detectably lower with DS salt balneophototherapy than with NB-UVB monotherapy (P = 0.099). The psoriasis severity score fell slightly more from beginning to end of courses with DS salt balneophototherapy than with NB-UVB monotherapy (P = 0.019). There was no detectable difference in times to relapse. CONCLUSIONS: In this population the addition of pretreatment DS salt soaks to NB-UVB did not result in a clinically important improvement in clearance of psoriasis.

Adult↗
PubMed2005

Ultraviolet A dosimetry in photopatch test centres in Europe.

OBJECTIVE: The aim of the study was to investigate the state of ultraviolet (UV) A dosimetry in photopatch testing centres in Europe. BACKGROUND: It has been acknowledged that a widespread disparity exists in the way photopatch testing is carried out in different countries throughout Europe. This prompted the formation of a European taskforce that developed a consensus methodology. One issue that was not addressed directly was that of UVA dosimetry, which clearly impacts on the consistency of the clinical results. STUDY DESIGN: Ten UV meters from photopatch test centres throughout Europe were set up at a reproducible position from a photopatch test light source containing UVA fluorescent lamps and the irradiances were noted from each meter. One meter served as a reference meter with calibration carried out in an optical laboratory traceable to the National Physical Laboratory. RESULTS: The mean of all the measurements was 5.74 mW/cm(2) with a SD of 0.36 mW/cm(2). Expanded uncertainty at 95% confidence level was 12%. CONCLUSIONS: It is desirable that meter calibration should have an accuracy of the order of +/-10%. The variation in recorded values among the 10 meters investigated was within acceptable limits. The meter must be calibrated using a similar light source to that used in the phototest equipment, in this case a UVA fluorescence lamp.

Calibration↗
PubMed2004

Treatment of superficial cutaneous vascular lesions: experience with the KTP 532 nm laser.

Whilst most facial telangiectasias respond well to short-pulse-duration pulsed dye laser therapy, studies have shown that for the treatment of larger vessels these short-duration pulses are sub-optimal. Long-pulse frequency-doubled neodymium:YAG lasers have been introduced with pulse durations ranging from 1-50 ms and treatment beam diameters of up to 4 mm. We report the results of KTP/532 nm laser treatment for superficial vascular skin lesions. The aim was to determine the efficacy of the KTP/532 nm laser in the treatment of superficial cutaneous vascular lesions at a regional dermatology centre in a 2 year retrospective analysis. Patients were referred from general dermatology clinics to a purpose-built laser facility. A test dose was performed at the initial consultation and thereafter patients were reviewed and treated at 6 week intervals. Outcome was graded into five classifications by the patient and operator independently based on photographic records: clear, marked improvement, partial response, poor response, and no change or worsening. Over the 2 year period, 204 patients with 246 diagnoses were treated [156 female; median age 41 (range 1-74) years; Fitzpatrick skin types I-III]. Equal numbers of spider angioma (102) and facial telangiectasia (102) were treated. Of those patients who completed treatment and follow up, 57/58 (98%) of spider angiomas and 44/49 (90%) of facial telangiectasia markedly improved or cleared. Satisfactory treatment outcomes, with one clearance and two partial responses, occurred in three of five patients with port-wine stain. Few patients experienced adverse effects: two declined further treatment due to pain, and a small area of minimal superficial scarring developed in one case. Two patients developed mild persistent post-inflammatory hyperpigmentation, and one subject experienced an episode of acute facial erythema, swelling and blistering after one treatment. The KTP/532 nm frequency-doubled neodymium:YAG laser is a safe and effective treatment for common superficial cutaneous vascular lesions in patients with Fitzpatrick skin types I-III.

Adolescent↗
PubMed2004

An update and guidance on narrowband ultraviolet B phototherapy: a British Photodermatology Group Workshop Report.

Summary These guidelines for use of narrowband (TL-01) ultraviolet B have been prepared for dermatologists by the British Photodermatology Group on behalf of the British Association of Dermatologists. They present evidence-based guidance for treatment of patients with a variety of dermatoses and photodermatoses, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of background photobiology.

Combined Modality Therapy↗
PubMed2004

Ground-level solar spectral irradiance in Glasgow: an inter-comparison of two sites.

BACKGROUND: Solar spectral radiometry presents significant challenges to produce accurate and reproducible data. To investigate the reliability of the measurements, several inter-comparisons have been set up. Although these are useful, their main drawback is that equipment must be dismantled and transported to a common site and re-calibrated. METHODS: In this study, an inter-comparison has been performed of two spectroradiometers that are located 3 miles apart some 30 m above sea level. These two systems have operated using different calibration techniques. Data were compared on clear days, to minimise actual differences in ultraviolet irradiation. RESULTS: There were substantial differences at some individual wavelength points, but overall the mean difference of results at 5 nm intervals on an individual scan from the two systems agreed to within 11%. If the data were used to compute the erythemal irradiance, the differences were reduced to 4%. CONCLUSION: This study demonstrates both the limitations and the level of reliability that might be expected from these systems operating under careful scientific supervision.

Geography↗
PubMed2004

The effect of photofrin on DNA strand breaks and base oxidation in HaCaT keratinocytes: a comet assay study.

Photodynamic therapy (PDT) kills cells via the production of singlet oxygen and other reactive oxygen species. PDT causes chromosomal damage and mutation to cultured cells. However, DNA damage does not contribute to the phototoxic effect. To study the effect of Photofrin-PDT-induced DNA damage, we used the comet assay in combination with endonuclease III and formamidopyrimidine DNA glycosylase and a human keratinocyte cell line to investigate photogenotoxicity and its prevention by tocopherol (TOC). This study shows that PDT induced DNA damage in HaCaT cells at doses allowing cells to survive 7 days after irradiation. alpha-TOC did not prevent the acute cell lysis caused by Photofrin-PDT but did prevent Photofrin-PDT-induced DNA damage. However, the concentration of TOC that conferred protection (100 microM) was higher than is detected in human serum. Base oxidation was also measured using the comet assay. Although TOC could prevent frank DNA strand breaks caused by PDT, it was unable to decrease the level of base oxidation as revealed by enzyme-sensitive sites. It is suggested that the potential genotoxic risk from laser-PDT could be low, and that topical micro-TOC at a high concentration may be useful in preventing some types of DNA damage without preventing acute photolysis after Photofrin-PDT.

Cell Line↗
PubMed2003

The potential hazard of laser pointers.

We have examined 30 laser pointers that have been removed from the possession of accused persons by police in Scotland. An analysis has shown that 28 were Class 3B (European), with radiated power up to 9.3 mW. We have reviewed the relevance of these findings and this shows that they are potentially hazardous if viewed directly. Transient exposure is unlikely to cause long-term damage but prolonged exposure may cause permanent retinal injury. They may also cause dazzle, the consequences of which could be serious.

Humans↗
PubMed2003

Topical 5-aminolaevulinic acid photodynamic therapy for cutaneous lesions: outcome and comparison of light sources.

BACKGROUND: Topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) is increasingly used for superficial non-melanoma skin cancers and their precursors. METHODS: We report our 3-year experience of topical ALA-PDT, with a preliminary comparison of the effects of broadband and laser light sources. RESULTS: We performed 688 treatments on 483 lesions in 207 patients. Complete clearance was achieved in 222/239 lesions of Bowen's disease (BD), superficial basal cell carcinoma (sBCC) and actinic keratosis (AK) (93%) - 117/129 BD (91%), 84/87 sBCC (97%) and 21/23 AK (91%), with a median follow up of 48 weeks. Broadband and laser light sources were of similar efficacy. Recurrences have occurred in 10.3% BD, 4.8% sBCC and 4.8% AK. Adverse effects from PDT were uncommon but included pigmentary change (2%) and minor scarring (2%). How-ever, severe pain was experienced in 16-21% of treatments using the high-output broadband and laser sources, but in only 2% with the low-output xenon arc source. CONCLUSION: Topical ALA-PDT is effective for BD, sBCC and AK and has been an invaluable addition to our dermatology service. Efficacy is similar for broadband and laser light sources, although treatment at higher surface irradiance may be painful, and excellent cosmetic results can be achieved.

Adult↗
PubMed2002

Laser and non-laser light sources for photodynamic therapy.

Photodynamic therapy (PDT) is an anticancer combination therapy, which requires a photosensitiser, which tends to accumulate preferentially in the tumour, and light. Historically large, complex lasers have been used to carry out PDT treatment. Nowadays there is a wide range of coherent and non-coherent sources that can be used. This paper considers the important characteristics of light sources for PDT, including dye lasers pumped by argon or metal vapour lasers and frequency-doubled Nd:YAG lasers. Non-laser sources including tungsten filament, xenon arc, metal halide and fluorescent lamps are also discussed. New exciting developments such as LEDs and femtosecond lasers are also reviewed. The relative merits of laser and non-laser sources are critically examined.

Humans↗
PubMed2002

Guidelines for topical photodynamic therapy: report of a workshop of the British Photodermatology Group.

Topical photodynamic therapy (PDT) is effective in the treatment of certain non-melanoma skin cancers and is under evaluation in other dermatoses. Its development has been enhanced by a low rate of adverse events and good cosmesis. 5-Aminolaevulinic acid (ALA) is the main agent used, converted within cells into the photosensitizer protoporphyrin IX, with surface illumination then triggering the photodynamic reaction. Despite the relative simplicity of the technique, accurate dosimetry in PDT is complicated by multiple variables in drug formulation, delivery and duration of application, in addition to light-specific parameters. Several non-coherent and coherent light sources are effective in PDT. Optimal disease-specific irradiance, wavelength and total dose characteristics have yet to be established, and are compounded by difficulties comparing light sources. The carcinogenic risk of ALA-PDT appears to be low. Current evidence indicates topical PDT to be effective in actinic keratoses on the face and scalp, Bowen's disease and superficial basal cell carcinomas (BCCs). PDT may prove advantageous where size, site or number of lesions limits the efficacy and/or acceptability of conventional therapies. Topical ALA-PDT alone is a relatively poor option for both nodular BCCs and squamous cell carcinomas. Experience of the modality in other skin diseases remains limited; areas where there is potential benefit include viral warts, acne, psoriasis and cutaneous T-cell lymphoma. A recent British Photodermatology Group workshop considered published evidence on topical PDT in order to establish guidelines to promote the efficacy and safety of this increasingly practised treatment modality.

Aminolevulinic Acid↗
PubMed2002

Guidelines for dosimetry and calibration in ultraviolet radiation therapy: a report of a British Photodermatology Group workshop.

This report examines the dosimetry of ultraviolet (UV) radiation applied to dermatological treatments, and considers the definition of the radiation quantities and their measurement. Guidelines are offered for preferred measurement techniques and standard methods of dosimetry. The recommendations have been graded according to the American Joint Committee on Cancer classification of strength of recommendation and quality of evidence (summarized in Appendix 5).

Humans↗
PubMed2002

Taking treatment to the patient: development of a home TL-01 ultraviolet B phototherapy service.

BACKGROUND: While most patients requiring phototherapy can attend for hospital-based out-patient ultraviolet (UV) B therapy, a significant number cannot attend because of geographical, work, economic and other reasons. OBJECTIVES: To determine whether there was a need for home phototherapy in the Tayside area and, if so, to establish protocols and then to assess if such a service would be workable. METHODS: Patients referred from dermatology out-patient clinics in Tayside for narrow-band UVB (TL-01) phototherapy completed a pilot questionnaire that was followed by a two-phase project. In phase 1, patients with psoriasis were trained to use the home phototherapy equipment (HoPE) within the hospital department under nursing supervision while a teaching package and protocols were developed. In phase 2, home phototherapy was made available for patient use in the community, supported by a specialist home phototherapy nurse. Waldmann UV100 home therapy units were used, with accurate dosimetry. Detailed treatment records were kept and questionnaires were used to assess acceptability and costs of therapy. RESULTS: Fifty-two pilot questionnaires were completed. Forty-two per cent of respondents found hospital phototherapy inconvenient and 75% felt phototherapy at home would be helpful. In phase 1, seven of 10 patients trained to use the HoPE completed therapy with the HoPE unit alone, reaching minimal residual activity (MRA) or clearance in a median of 18 exposures (median dose 10.38 J cm-2). In phase 2, 32 courses of home phototherapy were given to 30 patients. Of 23 with psoriasis, 18 reached clearance or MRA in a median of 22.5 exposures (median dose 9.84 J cm-2). Although self-reported erythema rates appeared higher than expected, all post-treatment questionnaire respondents would choose home phototherapy over hospital therapy if required in the future. CONCLUSIONS: UVB (TL-01) home phototherapy is a useful practical development that has fulfilled a need in our catchment area. Where appropriate training and support teams are available it appears to be similar in effectiveness to hospital therapy, to be safe and to be cost-effective for patients.

Adult↗