Retina: ultrastructural alterations produced by extremely low levels of coherent radiation.

The effect of low levels of coherent radiation on the eye is not fully established, but is generally presumed to be noninjurious. Irradiation of the retina with a Q-switched ruby laser emitting low amounts of energy (0.1 percent probability of creating damage) consistently produces ultrastructural alterations in rods and cones. Outer segments of these cells are broken and disorganized and their lamellae are in disarray 1 day after such irradiation.