A review of targeted ultraviolet B phototherapy for psoriasis.

Targeted ultraviolet (UV) B phototherapy devices provide a practical means to treat localized psoriasis while sparing harmful effects to unaffected skin. The objective of this study was to characterize the efficacy and safety of targeted phototherapy devices for psoriasis. We conducted a PubMed search for broadband UVB, narrowband UVB, and localized phototherapy, and a Google search for handheld phototherapy. The most common targeted phototherapy devices were characterized as 308-nm excimer laser, 308-nm excimer nonlaser, or nonexcimer light subtypes. Nine clinical trials met inclusion criteria and all found targeted phototherapy efficacious. In a nonexcimer light study, high doses cleared the most plaques. The 308-nm excimer laser had long-term clearance in 13 of 26 patients. The mean number of UVB treatments in all 9 studies and highest cumulative dose was less than those same parameters in nontargeted phototherapies. Common adverse effects included erythema, blisters, hyperpigmentation, erosion, mild burning, and itching. The predominant setting for excimer units is the office; however, the majority of nonexcimer light devices can also be used at home. Targeted phototherapy should be considered among the treatment options for localized variants of psoriasis.