ARGON-LASER PHOTOCOAGULATION OF FLUORESCEIN STAINED RETINA - AN UNRECOGNIZED HAZARD

Sodium fluorescein staining of the retina following fluorescein angiog raphy may affect the absorption characteristics of argon ion laser pho tocoagulation. This hypothesis was investigated by performing laser ph otocoagulation on control and fluorescein stained porcine retinas. The resultant damage was viewed by scanning electron microscopy. In both specimens, argon irradiation produced damage to the pigment epithelium and overlying photoreceptor layer. The control sample showed a deep c ylindrical burn, indicative of internal heating, in both retina and ch oroid. The fluorescein stained sample showed damage consistent with th ermal interaction from the surface downwards leaving the choroid relat ively spared. This preliminary study demonstrates that fluorescein sta ining of the retina changes the absorption site of argon laser light a nd this subject clearly merits further investigation.