Contrast sensitivity peripheral to an absolute central scotoma in age-related macular degeneration and the influence of a yellow or an orange filter.

Contrast sensitivity for static and dynamic gratings was determined in 17 patients with age-related macular degeneration (AMD) and an absolute central scotoma. Using electronic and computerized equipment, we established contrast sensitivity peripheral to the scotoma at spatial frequencies of 0.5, 1.0 and 2.0 cycles/degree. We found that mean contrast sensitivity was significantly (p < 0.001) lower than that of a control group at a comparable eccentricity, and that interindividual variations were large. Furthermore, we investigated the influence of a yellow and an orange filter on contrast sensitivity peripheral to such an absolute central scotoma in AMD. The results showed significant (p < 0.01-0.05) improvements in contrast sensitivity at certain spatial frequencies only, i.e., for the yellow filter at 2.0 c/deg and for the orange filter at 0.5 and 1.0 c/deg, and only with dynamic presentation. No objective improvement in visual acuity could be demonstrated when using filters. Thus, our findings do not unequivocally support the regular prescription of such filters in order to improve contrast vision in AMD with an absolute central scotoma.