The significance of ultraviolet radiation for eye diseases. A review with comments on the efficacy of UV-blocking contact lenses.

Acute and cumulative ultraviolet radiation (UVR) exposure has been proposed as an important causative factor in the development of a whole spectrum of eye diseases. The present review examines the scientific evidence for and against such an association, with special emphasis on recent additions to the literature. The sun is the main UVR source on earth, and it is beyond scientific doubt that the cornea can be harmed by both acute and cumulative ambient exposures. There is also powerful epidemiological support for an association between chronic UVR exposure and the formation of cataracts and pterygia. The evidence in support of UVR linkage to pinguecula, ocular neoplasms and retinal changes is weaker--in part because there are fewer studies reported in the literature. It is concluded that UVR-blocking hydrogel contact lenses and spectacles are two equally effective preventive measures in minimizing unnecessary suffering and health costs, especially for people who spend a significant time outdoors and for those who live in more UV intense environments. UVR-blocking contact lenses and spectacles must not, however, be substitutes in situations that require UVR-blocking safety goggles.