Using UVB 311 nm Narrow-Band Medical Lamp for the Treatment of Psoriasis

Abstract

Ultraviolet B (UVB) light is effective in eliminating symptoms of psoriasis and the overall dosage of the narrow-band radiation can be closely controlled, which makes UVB lamps suitable for home therapy. Utilizing phototherapy, this study proposes a psoriasis treatment method which applies 311 nm narrow-band UVB (NB-UVB) to improve efficacy and reduce long-term toxicity comparing to other recent treatments. One device was designed and built—from a Philips UVB Narrow-band medical lamp and a controlling digital circuit comprising of an 89S52 microcontroller, a LCD screen, and a DS1307 real-time clock—to illuminate the psoriasis lesions in a controllable exposing time. An in vitro study was established on mouse skin fibroblasts to investigate the effect of NB-UVB on cell proliferation and morphology. The efficacy and safety of the lamp were also examined on two patients of psoriasis. The obtained results showed no significant abnormal change in morphology and growth of the irradiated fibroblasts. Furthermore, in patients undergoing the therapy, improvement was observed after 6 weeks of treatment. The psoriasis scales were fewer and the skin was softer and less flushed. The skin lesions also did not itch and spread out. The mechanism of action of the proposed treatment, however, remains not fully understood and would be further studied by investigating the effect of NB-UVB on key cell types involved in the pathogenesis of the disease including the keratinocytes and the T lymphocytes. The system will also be upgraded with various components, such as UV light sensor, for safe uses.