Dynamic Dye-Enhanced Laser Photocoagulation

Candela Laser Corporation, in cooperation with The Johns Hopkins University, will develop a new procedure for treatment and closure of choroidal vessels and neovascular membranes with reduced damage to the retina and better preservation of vision. Choroidal neovascularization is the most frequent cause of blindness in patients over the age of 65. The success of current argon/krypton laser treatments is severely limited by patient eligibility criteria, a high recurrence rate, and loss of vision due to the treatment itself. The treatment procedure to be evaluated in this study uses small doses of Indocyanine Green injected prior to each laser burn to selectively enhance absorption of laser light in the designated target area during laser irradiation. In contrast to previous studies, dye concentration is monitored precisely. Laser energy is delivered during the transit of a dye bolus or when the dye concentration reaches its maximum in the target area. A diode laser at 805 nm, matched to the absorption maximum of ICG will be coupled to an infrared video fundus camera delivery system. Optimum parameters for dynamic dye-enhanced laser treatment will be evaluated in a rabbit model in the Phase I study.