Photodynamic therapy with topically applied @entity2518 is used successfully for superficial @entity272 . The results for thicker, nodular lesions are less favorable. The method of @entity8454 administration, the concentrations of @entity8454 , and the irradiation schemes used so far have not been investigated thoroughly. As @entity8454 photodynamic therapy has high potential for the increasing problem of @entity1489 , we investigated both visually and histopathologically the photodynamic-therapy-induced @entity272 after intracutaneous administration of @entity8454 in normal porcine skin. We also investigated the kinetics of the @entity8454 -induced photosensitizer @entity13880 fluorescence after irradiation in relation to fluence and irradiance. Finally we investigated the effect on photodynamic-therapy-induced damage of a fractionated irradiation. This study demonstrates that intracutaneous administration of @entity8454 leads to higher fluorescence levels and thus to formation of higher @entity13880 concentrations than topical application of @entity8454 cream. The peak level of @entity13880 after intracutaneous administration of @entity8454 is reached earlier than after topical administration. The comeback of fluorescence, indicating re-synthesis of @entity13880 after irradiation, is inhibited with increasing fluence. Photodynamic-therapy-induced damage increases with increasing fluence, but is independent of the irradiance. Finally, the photodynamic-therapy-induced @entity272 seems to be greater after fractionated irradiations with two equal light fractions of 15 J per cm2 separated by a dark interval of 2 h.

PpIX fluorescence kinetics and XXXX after intracutaneous injection of @entity2518 and repeated illumination.

@entity1489 :: ('MESH:D012878', 'Disease') :: ['skin cancer'] @entity2518 :: ('CHEBI:17549', 'Chemical') :: ['5-aminolevulinic acid'] @entity13880 :: ('MESH:C028025', 'Chemical') :: ['protoporphyrin IX'] @entity272 :: ('MESH:D012871', 'Disease') :: ['skin lesions', 'skin damage'] @entity8454 :: ('MESH:D000622', 'Chemical') :: ['aminolevulinic-acid', 'aminolevulinic acid']
@entity272 :: (MESH:D012871,Disease) :: ['increased skin damage']
