Treatment of Psoriasis with an 308 nm Excimer Laser

Overview

The authors present the results of a clinical study using an 308 nm excimer laser for treatmentof chronic localized psoriasis. After assessment of the individual MED (minimal erythema dose), thepatients were treated 6x (17 patients) or 10x (11 patients) with UVB radiation of wave length 308 nm.Individual doses varied within the range of 2-5multiples of MED. During 2-3-week treatment theauthors achieved in the absolute majority of patients significant improvement of the clinical findingas apparent from the decline of the psoriatic score (PS) of the treated areas and illustrations. Thepatients were followed up as part of the study for 3 months after completed treatment. In the majoritysignificant improvement of the clinical finding persisted at least for one month after termination oftreatment. After an interval of 2-3 months following termination of treatment, gradual exacerbationof psoriasis developed, which however did not reach the pretreatment level.The excimer laser emitting UV radiation of wave length 308 nm is a new possibility of treatmentof chronic localized psoriasis. Contrary to commonly used methods of conventional phototherapy,only psoriatic lesions are exposed toUV radiation and not the healthy skin. With regard to the greaterresistance of psoriatic lesions to the effects of UV radiation in the described method supraerythematousdoses may be used. The method makes it possible to shorten markedly the time needed toimprove or cure the clinical finding and to reduce the whole body cumulative dose of UV radiation.

Key words:
excimer laser - psoriasis - UV radiation - phototherapy