P 408 Growth factor profiles in pig eyes following scatter laser photocoagulation

Purpose: To compare the histhologic changes in the retina and chowid, between the continuous and pulsed-wave photocoagulation by diode laser in pigmented rabbits. The r6petitivepulse photocoagulation could prove to be a promising technique for several pathologies in the ocular fundus. Methods: Continuous and pulsed diode-laser transpupillary photocoagulation~ was performed in the eyes of pigmented rabbits using a semiconductor laser emitting infrared radiation (810nm.). The power used was 150mw. and the spot size was 200~. The exposure time was 2OOmsec. for the continuous wave and in the form of 20 pulses spaced by 5msec. interval the pulsedmode. The animals were Pacified two and seven days after the treatment to’ hlthologic study. Results: In the areas treated with pulsed-wave, the most intensive alterations appeared in the outer retina three days after the treatment, while all the retinal layers were affected in case of using continuous wave. The retinal repair was observed seven days post-photocoagulation in the form of scar tlsuue containing hyperpigmented cells. Conclusions: The histhologic effects of the continuous and pulsed-wave are similar; however in the continuous wave, all the retina is affected while in the pulsed the neural retina is more preserved.