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Notes: Summary Benzophenone-3 (BZ-3) is a commonly used, chemical UV-absorber. It has been used for many years to protect against UV-radiation. Previous studies have shown that BZ-3 penetrates the skin, and it can be found in urine, faeces, and blood. In this study we examined the percutaneous absorption of BZ-3. The amount of BZ-3 absorbed was measured in urine, as experimental studies in the rat have shown that urine is the major route of excretion. Eleven volunteers applied the recommended amount of a commercially available sunscreen and urine samples were collected during a 48-h period after application. The average total amount excreted was 11 mg, median 9.8 mg, which is approximately 0.4% of the applied amount of BZ-3. Some of the volunteers still excreted BZ-3 48 h after application. It is evident that BZ-3 undergoes conjugation in the body to make it water soluble. However, we do not know at what age the ability to conjugate is fully developed, and therefore for children physical filters such as titanium dioxide and/or zinc oxide might still be considered a more appropriate sunscreen component.

Notes: Summary Pain resulting from photodynamic therapy (PDT) of skin cancer was investigated. The study included 69 lesions (60 patients) with different types of skin tumours or precursors. Protoporphyrin IX, which is produced by the topical application of δ-aminolevulinic acid, was used as a photosensitizing agent. Twenty-three of the lesions (19 patients) were examined with a fluorescence imaging system which demarcates the tumour area from the healthy skin and visualizes the contrast between the fluorescence from healthy skin and that from the tumour. EMLA® is used on all patients as part of our routine PDT protocol but despite this the major side-effect of PDT is pain during treatment. There is a large variation in pain intensity experienced by the patients, as measured by a visual analogue scale (VAS). Patients with actinic keratoses experienced more pain than those with Bowen's disease or basal cell carcinoma. The mean VAS score was higher when treating lesions located on the head than when treating lesions on the torso or the extremities. Also, treatment of large skin areas resulted in more pain than treatment of small areas, and men experienced more pain than women. The pain experienced by the patients did not correlate with treatment dose, Fitzpatrick skin type, age or fluorescence intensity.

Notes: Mohs' micrographic surgery (MMS) is the recommended treatment for large basal cell carcinomas (BCCs) of the nose. This 5–year follow–up study attempts to evaluate whether curettage–cryosurgery (CC) could be an alternative therapy in a country where optimal resources for MMS are lacking. All patients with a primary nasal or perinasal BCC, 10 mm or larger in diameter, were assessed at a skin tumour clinic. Sixty–one BCCs of non–morphoeiform type were treated with CC. Most of the tumour was removed by careful curettage with different sized curettes. The tumour area was then frozen with liquid nitrogen in a double freeze–thaw cycle. Fifty patients were followed for at least 5 years with only one recurrence. The cosmetic result was good or acceptable in all patients. A thorough curettage followed by cryosurgery could be a safe and inexpensive alternative therapy even for large primary non–morphoeiform BCCs of the nose.

Notes: Measurements have been made of the biologically-effective environmental UV-B radiation [UV-B(BE)] received by people in different occupations in Sweden. These UV-B(BE) doses have been compared with those received from artificial UV-B radiation by patients undergoing phototherapy for psoriasis. The results indicate that for patients with outdoor occupations the therapeutic dose contributes something like one third of their total UV-B(BE) presumably only to the hands and face. For patients who work indoors, however, the therapeutic dose can be anything from 50%to almost 100% of their total UV-B(BE) burden.

Notes: Delta-aminolevulinic acid (ALA) is used for photodynamic therapy of basal cell carcinoma (BCC) as it is converted to protoporphyrin IX in tumour tissue. During illumination with 635 nm light a photochemical reaction takes place, singlet oxygen is generated and the tumour destroyed. In this study we used the microdialysis technique to quantify the concentration of ALA at a certain depth in tumour and healthy skin. The penetration ability of ALA was investigated as a function of time in BCCs (n = 14) and in normal skin (n = 4) after topical application. The microdialysis catheters were inserted intracutaneously and the depth position recorded by means of ultrasound. Microdialysate sample concentrations of amino acids and ALA were determined by high performance ion-exchange chromatography. A laser Doppler perfusion imager measured perfusion in the BCCs. The data show that the average depth of the microdialysis catheters was 0.5 mm. The interstitial ALA concentration in the BCCs increased from 0 to 3.1 mmol/L 15 min after application of ALA, whereas no measurable amounts of ALA were found in healthy skin. The blood perfusion was 2.5-fold increased in the BCCs. The interstitial levels of amino acids were not significantly changed during the ALA treatment. In summary, we found that ALA rapidly penetrates tumour skin. We conclude that microdialysis seems to be well suited for pharmacodynamic studies of ALA in skin.

Notes: Summary In a paired-comparison study, 21 patients suffering from atopic dermatitis were treated with fluorescent tubes radiating mainly ultraviolet A (UVA) on one half of the body and with tubes radiating mainly UVB on the other. Treatment was given three times a week for up to 8 weeks. Eight variables reflecting disease status were recorded and the sum of these comprised the total score. The total score and the overall evaluation score were better with UVA therapy (p〈0·02 and P=0·01, respectively. No statistically significant difference for the pruritus score was found. The reduction in extent of dermatitis, seen with both therapies, was more pronounced with UVA (P〈0·05). Differences in the healing score were not statistically significant. Treatment with UVA resulted in healing or considerable improvement in 15 patients and 13 patients showed improvement when treated with UBA. A better result was found with UVA in 10 subjects and with UVB in two subjects. Equal results occurred with both UVA and UVB in nine of the patients although most preferred UVA treatment.

Notes: The ultraviolet radiation (UVR) doses received by staff who are occupationally exposed to artificial sources of UVR found in dermatology departments have been measured using personal UV monitors. The results show that staff may receive actinic (UVB and UVC) doses which are in excess of recommended maximum permissible limits for occupational exposure, but that the UVA doses are well within these limits.

Notes: Background  Although photodynamic therapy (PDT) is becoming an important treatment method for skin lesions such as actinic keratosis (AK) and superficial basal cell carcinoma, there are still discussions about which fluence rate and light dose are preferable. Recent studies in rodents have shown that a low fluence rate is preferable due to depletion of oxygen at high fluence rates. However, these results have not yet been verified in humans.Objectives  The objective was to investigate the impact of fluence rate and spectral range on primary treatment outcome and bleaching rate in AK using aminolaevulinic acid PDT. In addition, the pain experienced by the patients has been monitored during treatment.Patients/methods  Thirty-seven patients (mean age 71 years) with AK located on the head, neck and upper chest were treated with PDT, randomly allocated to four groups: two groups with narrow filter (580–650 nm) and fluence rates of 30 or 45 mW cm−2, and two groups with broad filter (580–690 nm) and fluence rates of 50 or 75 mW cm−2. The total cumulative light dose was 100 J cm−2 in all treatments. Photobleaching was monitored by fluorescence imaging, and pain experienced by the patients was registered by using a visual analogue scale graded from 0 (no pain) to 10 (unbearable pain). The primary treatment outcome was evaluated at a follow-up visit after 7 weeks.Results  Our data showed a significant correlation between fluence rate and initial treatment outcome, where lower fluence rate resulted in favourable treatment response. Moreover, the photobleaching dose (1/e) was found to be related to fluence rate, ranging from 4·5 ± 1·0 J cm−2 at 30 mW cm−2, to 7·3 ± 0·7 J cm−2 at 75 mW cm−2, indicating higher oxygen levels in tissue at lower fluence rates. After a cumulative light dose of 40 J cm−2 no further photobleaching took place, implying that higher doses are excessive. No significant difference in pain experienced by the patients during PDT was observed in varying the fluence rate from 30 to 75 mW cm−2. However, the pain was found to be most intense up to a cumulative light dose of 20 J cm−2.Conclusions  Our results imply that the photobleaching rate and primary treatment outcome are dependent on fluence rate, and that a low fluence rate (30 mW cm−2) seems preferable when performing PDT of AK using noncoherent light sources.

Notes: UVB phototherapy of atopic dermatitis was investigated in two paired-comparison studies. In study 1, 17 patients were treated for 8 weeks with ultraviolet B radiation (UVB) on one half of the body and with visible light (placebo) on the other. A severity score based on eight clinical variables was determined before, during and after treatment. The total score, pruritus score and overall evaluation score were significantly better on the UVB treated sides than on the placebo treated sides (P 〈 0.001). In 13 patients the UVB treated side healed or improved considerably, while the placebo treated side improved considerably in one patient only.In study II, 25 patients were treated for 8 weeks with 0.8 of the minimal erythema dose (MED) of UVB on one half of the body and with 0.4 MED UVB on the other. No statistically significant differences between these dosage regimens were found.

Notes: Measurements have been made of the biologically-effective environmental UV-B radiation received by people pursuing a variety of outdoor leisure activities. These UV-B doses have been compared with those received from artificial UV-B radiation by patients undergoing treatment for psoriasis. The results indicate that the therapeutic doses are not dissimilar to those received by active sunbathing for the same period during the summer months.