Narrow band Ultraviolet B 311 nm in the treatment of vitiligo: two right-left comparison studies

Evaluation of narrow band ultraviolet B (NB UVB 311 nm) in the treatment of vitiligo by two independent studies. The first study compared NB UVB with a well-established therapeutic modality, psoralen ultraviolet A (PUVA), and the second study was conducted to find out whether psoralen might add to its efficacy. In the first study, 15 patients were exposed on the left half of their body to UVB 311 nm and then exposed on their right half to UVA after ingestion of psoralen. In the second study, 20 patients were exposed to UVB 311 nm on the left side of the body, followed by ingestion of psoralen and exposure to NB UVB 311 nm 90 min later to the right side of the body. In both studies, while exposing one side, the other was protected by an UV-proof gown. Thus two right-left comparative studies were carried out simultaneously, namely: UVB 311 nm vs. PUVA and UVB 311 nm vs. PUVB 311 nm. In the first study, comparison of PUVA and NB UVB 311 nm showed no difference either in the degree of response or in the incidence of complications. In the second study, comparison of PUVB and UVB showed equal clinical improvement on both sides. The cumulative dose needed to achieve the same response on the PUVB side was lower than that on the UVB side, but the difference was not statistically significant. The incidence of phototoxic reactions was significantly higher on the PUVB treated body half. NB UVB 311 nm has similar repigmentary effects as PUVA. The addition of psoralen does not increase its efficacy.