Serous retinal detachments have been produced experimentally by occluding the choroidal circulation. We sought a more realistic model by adjusting rose bengal photosensitization to injure the retinal pigment epithelium and choriocapillaris in rabbits without causing vascular occlusion. We accomplished this by either using low doses of rose bengal or cooling the animal to reduce ocular temperature by 4 degrees C. Detachments typically appeared within 1 day after light exposure, centered over the area of light damage. Fluorescein angiography showed no capillary occlusion, but there was leakage of dye from areas of light damage. Light microscopy of light-damaged areas showed swelling or disruption of retinal pigment epithelial cells but a patent choriocapillaris. These data suggest that a combination of retinal pigment epithelial and choriocapillary damage may be necessary for serous detachment to occur.