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Update on Phototherapy and Photoprotection
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Broadband UVB is the oldest type of phototherapy. Indications include psoriasis, atopic dermatitis, prutirus, CTCL, HIV associated eosinophitic folliculitis

The protocol for BB UVB (270-290 nm) for skin types I/II is to begin with 50% MED-B and increase by 50%/40/30/20/10% increments.

For skin types III, IV, you begin with 60% MED-B and increase by the same increments.

Another protocol is to begin at 15 mJ/cm2 for skin types I, II, 30 mJ/cm2 for types III, IV, and 45mJ/cm2 for skin types V-VI.

The question of the association of non-melanoma skin cancer and UVB was addressed in the Archives of Dermatology in July 1999. The evidence was insufficient to quantify an excess incidence of non-melanoma skin cancer. The incidence is unlikely to exceed 2% per year which is less than PUVA.

Narrowband UVB is much more efficient (313nm). In 1984 the TL-01 (Philips) bulb was developed which delivers 311-312 nm. European studies were published in 1988 and US studies in 1997.

Indications include psoriasis, viligo, CTCL, PMLE and atopic dermatitis. Dr. Lim then reviewed a number of studies examining the effectivesness of Narrowband UVB.

A study in the Archives in 1997 compared NB vs BB UVB both with and without tar. Twenty-two patients with psoriasis were treated daily with narrowband UVB, 86% of lesions had clinical resolution versus 73% with Broadband. Narrowband were also significantly better than BB with tar.

In the Archives in 1999, NB was compared to PUVA in 25 patients. The PASI score decreased 84% with NB-UVB versus 89% with PUVA.

Combination therapy of NB-UVB with tazarotene was studied on 10 patients in the JAAD 2000:42:493. At both two weeks and four weeks of therapy, NB-UVB plus tazarotene was better than NB-UVB alone. In contrast, calcipitriol with NB-UVB had no increased effectiveness.

NB-UVB has been used for Vitiligo. In the Archives 1997, Westerhof compared topical PUVA and NB-UVB done twice weekly. Repigmentation was noted after four months in both groups. A study of 51 children treated with NB-UVB for Vitiligo noted 53% of patients with greater than 75% repigmentation and 80% with stabilization of disease.

NB-UVB has been used for treatment of CTCL. (Archives 1999) 20 patients, six with patch stage and 14 with small plaques stage were studied. In 19 patients there was clinical and histological clearing, however, all relapsed within nine months.

In the Archives in June 2000, eight patients, all with patch stage MF, received NB-UVB three times per week. Six of eight patients obtained clinical clearance after 26 treatments (approximately 9 weeks). Duration of clinical improvement was 20 months. Therefore, NB-UVB is an alternative therapy for patch stage MF.

NB-UVB has also been used for PMLE densitization. A study by Man using NB-UVB three times per week for five weeks resulted in 63% of patients with a good response and 26% with a moderate response.

Other indications for NB-UVB are atopic dermatitis, seborrheic dermatitis and photodermatitis.

A protocol used is to start with 70% MED and increase by 15% per treatment. The mean MED skin types I-III is 200-600 mJ/CM2 and for IV-V 650-1600 mJ/CM2.

Side effects of NB-UVB include erythema similar to NB-UVB.

NB-UVB is two-three times more carcinogenic per MED than Broadband UVB in the animal model, however, as NB-UVB is more efficient, to clear psoriasis the MED of NB is less than BB. Therefore, the long term carcinogenic risk of NB is probably no more than BB.

The 308nm Eximer Laser is a new form of phototherapy. In the Archives in May 2000, 13 patients with psoriasis were studied (four plaques each). Eight doses were delivered to each plaque either low (.5, 1 time MED), medium (2-6 times MED), or high 8-16 times MED) dose. All patients were treated from 1-20 treatments, at two times per week. After four weeks, the high dose group was significantly better than the medium and low dose groups. After four months, the low and medium groups had a recurrence. The high dose group remained in remission. This laser has also been studied in Vitiligo. The proximal extremities were more responsive than the distal extremities.

Indications for UVA include atopic dermatitis usually in combination with UVB, solar urticaria, and psoriasis.

A newer form of UVA is UVA1 (340-400nm). There are three different ways of delivering this phototherapy; High (130J/cm2), medium (50J/cm2) and low (20J.cm2). The indications are localized scleroderma, systemic sclerosis, urticaria pigmentosa, CTCL, Graft vs host disease, generalized GA, and atopic dermatitis.

UVA1 is currently not approved in the USA. Limitations include the cost (approximately $50,000), and also treatment times. The long term side effects are still unclear.

Visible light was discussed next. Use in acne was studied in the BJD in May 2000. Blue (415 nm) and red (660 nm) were used in 107 patients who received one of four treatments. The combination group of blue and red light after 12 weeks had a 76% improvement in inflammatory lesions and 58% comedone improvement.

Dr. Lim concluded his lecture with a review of photoprotection, including the FDA sunscreen monograph and the AAD response and use of fabrics in sunprotection.

Henry W. Lim, M.D. Professor and Chairman of the Department of Dermatology Henry Ford Hospital Detroit, Michigan


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