A new apparatus for the delivery of high intensity UVA and UVA+UVB irradiation, and some dermatological applications.

A new apparatus consisting of a 200 W super pressure mercury lamp and a flexible light guide with a liquid light-conducting core is presented. Its transmission for UVA irradiation is more than threefold as compared to conventional quartz fibre optic bundles. The light guide is capable of transmitting density levels exceeding I W/cm2. UVA and UVB are transmitted. By inserting a filter platelet (WG 345) into the light guide the UVB is cut off. The output of the unfiltered guide is 700 mW (3570 mW/cm2), of the filtered guide 400 mW (2040 mW/cm2), centered mainly at 366 nm. The light apparatus proved useful for several dermatological applications. It replaces in many respects conventional Kromayer lamps, especially because the flexible light guide, which is 160 cm long and weighs only 210 g, can be brought into direct contact with the skin. Results of determining the minimal erythema dose (MED), of phototesting (8-MOP photoallergy, persistent light reactor, erythropoietic protoporphyria) and of photochemotherapy are given.