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Abstract
Retinal damage caused by high-intensity light is generally due to a temperature increase in the fundus. Until the present time, it has not been possible to accurately measure this temperature rise. A procedure is described and results presented to show the dynamic temperature changes in the fundus caused by laser light and to compare the experimental results with a published retinal temperature model. Temperature rise was found to be directly proportional to input power to the eye, but highly dependent on the shape and size of the retinal image. Our measured temperature increases at the end of 10 seconds of irradiation with a CW argon laser were an average of 30 per cent higher than model predictions for near steadystate emperatures. It was also found that the retinal image size must be very much larger than the temperature probe for accurate measurements. Measured temperatures were generally lower than model predictions for times less than 100 milliseconds. Temperature distributions measured across the retinal image in the pigment epithelium compared very favorably with model predictions. Perspective views of two-dimensional temperature profiles across the pigment epithelium and choroid are presented for both measurements and model.