Sunlight and Age-Related Macular Degeneration-Reply

In Reply.  —A wide spectrum of radiation exists in sunlight, and it is important to consider the wavelength when evaluating possible retinal damage associated with sunlight exposure. The data of Pitts et al¹ and Boettner and Wolter² on transmittance suggest that a small but significant portion of the UV spectrum reaches the retina, and we and others have suggested the importance of evaluating possible increased risk associated with such exposure.Primary damage to the retina, specifically to the photoreceptors, does appear to follow the absorptive spectrum of rhodopsin, as shown by Noell et al. However, photochemical damage to the retinal pigment epithelium is also a mechanism of light damage and, as Ham et al and others have suggested, appears to follow the absorption spectrum of melanin, which extends into the UV range. In fact, the melanin absorption curve increases markedly toward the shorter wavelengths.³ Thus, retinal damage