Clinical, pathological and photochemical studies of laser injury of the retina.

Nineteen cases of acute accidental laser injury of the human retina and two groups of laser workers with chronic retinal damage were reviewed. Most acute cases had macular injury and vision impairment; the chronic cases usually suffered from nonspecific eye complaints. Pathological and photochemical studies of laser injury to rabbit retina were also made following exposure to a 0.49-W Ar laser. The retinal pigment epithelial cells and photoreceptors were mildly damaged in the laser spot center, but the Bruch's membrane was still intact. Malondialdehyde (MDA), the main degradation product of lipid peroxidation of the retina, was assessed with fluorescence spectrophotometry. The level of MDA in the injured retina was significantly higher than that in control eyes, suggesting that thermal levels of Ar laser exposure can yield evidence of photochemical light damage mechanisms.