This video reviews the retinal cell changes and retinal pigment epithelium (RPE) regeneration during and following laser photocoagulation.

In 10-ms treatment, laser light is absorbed primarily in the RPE and choroid. Heat diffusion results in an expanding zone of coagulation. With 100-ms pulses, heat generated in the RPE and choroid diffuse through the full thickness of the retina.

Following laser treatment, RPE cells start migrating and stretching into the damaged zone on day 1, and they completely fill in the damage zone within a few days. Cells start proliferating around day 3, and the RPE layer structure continues to normalize over a few weeks following injury.