Asymptotic Rate Process Calculations of Thermal Injury to the Retina Following Laser Irradiation

Abstract

Thermal damage to the retina following laser irradiation may be predicted using impulse and steady asymptotes derived from a first-order rate process and a simple thermal model for two time domains. Effects which have been observed experimentally in the short pulse (<10−4 s) region such as changes in energy per unit area for threshold damage as a function of image diameter may be explained with this model. The model allows rapid damage prediction without extensive calculations of temperature increase which normally require a large computer. Thermal damage to the ocular fundus resulting from a long pulse exposure may also be easily described with a simple steady-state model for temperature increase and damage.