VISION TESTING IN ATROPHIC MACULAR DEGENERATION

Purpose: To determine the correlation between a group of vision tests in atrophic macular degeneration (AMD) in an office setting. Methods: Patients with documented vision loss from atrophic macular degeneratio n in one eye were invited to attend an eye clinic every three months f or a series of six vision tests for their good eye followed by fundus photography. Modified contrast sensitivity, blue/yellow anomaloscopy, flicker fusion frequency, Amsler grid, and photostress recovery time w ere correlated with Snellen acuity using the Pearson correlation coeff icient. The regression of the Snellen acuity result on sex, age and th e presence of disciform macular degeneration in the other eye was obta ined using a general linear model. Results: The correlation with Snell en acuity result was low for all tests. It was highest for Amsler grid abnormality (r = -0.33345) and blue/yellow anomaloscopy matching rang e (r = -0.20742), where r denotes the correlation coefficient. Patient age was strongly correlated with Snellen results (P = 0.0001), but it was not significantly related to sex (P = 0.1137) or the presence of disciform macular degeneration in the other eye (P = 0.9989). The phot ostress recovery time showed enormous inter-visit variations and poor correlation with Snellen acuity (P = 0.0526). Conclusions: The course of AMD is routinely assessed by Snellen acuity and any of several addi tional tests. When employing a test battery in an office setting, a cl inician needs to know the relative utility and correlation between the tests at his disposal. Of the tests used in this study, the Amsler gr id was the most useful addition to the Snellen acuity at all stages of atrophic macular degeneration, and blue/yellow anomaloscopy was usefu l only in mild macular degeneration where Snellen acuity was 6/12 or b etter.