Clinical studies on high and low power laser radiation upon some structures of the anterior and posterior segments of the eye. Experiences in the treatment of some pathological conditions of the anterior and posterior segments of the human eye by means of a Nd:YAG laser, driven at various power levels.

A Q-switched Nd:YAG laser apparatus has been used in the treatment of a number of pathological conditions of the anterior and posterior segments of the human eye. This laser system may be driven in a free running mode, thereby allowing variation of pulse duration over a range of 12 ns to 10 ms. With increasing pulse duration, non-linear mechanical damage patterns characteristic of the biological effects at the lower exposure duration range become unimportant when compared to the so-called thermal effects met at the upper pulse duration range. The thermal damage mechanisms may be useful when applied together with the mechanical damage mechanism, for instance when iris perforations are intended. Because the Wise-Witter irradiation method for the treatment of open angle glaucoma depends on low power, thermal mechanisms, this instrument may also be useful for the treatment of this disease entity. This same irradiation mode may also be applied to at least some irradiation tasks of the retina and choroid.