DIRECT COMPARISON OF INVITRO AND INVIVO PHOTOFRIN-II MEDIATED PHOTOSENSITIZATION USING A PULSED KTP PUMPED DYE-LASER AND A CONTINUOUS WAVE ARGON ION PUMPED DYE-LASER

A pulsed KTP pumped dye laser (25 kHz repetition rate and 470 nsec pulse width) has been compared to a continuous wave argon ion pumped dye laser as the source of 630 nm light during in-vitro and in-vivo Photofrin-II mediated photosensitization studies. Individual experiments documented the effectiveness of each laser system on a) photosensitizer induced cytotoxicity and induction of stress protein synthesis using Chinese hamster fibroblasts; b) photobleaching of Photofrin-II in aqueous solution; c) Photofrin II mediated photosensitization of normal mouse skin; d) Photofrin II mediated photodynamic therapy of a mouse mammary carcinoma; and e) tumor temperature levels generated during laser exposure. Comparable results were obtained for both laser systems in all experiments.