Comparative vision tests using objective and subjective testing methods in amblyopia

Abstract

In 20 amblyopic eyes without reading ability a comparison was made between the visual acuity found by subjective tests and with the Catford Visual Acuity Apparatus, Kotowski's Visumeter and Lotmar's Moiré Visometer. These instruments all work on the basis of different physiological functions. The Kotowski Visumeter seems to be the best instrument for an expertise on the visual acuity of an amblyopic eye. With the test pattern moving from nasal to temporal the results corresponded to the patients reading ability in 16 cases (80%); 4 patients had poorer vision. With the checkerboard pattern moving temporonasally the average results were better than the patients' actual vision. The Catford apparatus gave results corresponding to the subjective reading test only in 12 cases (60%). Apparatus with interferometric scales are not suitable for objective visual testing of amblyopic subjects; the results they give are always much better than the actual vision of the patient.