This study aimed to evaluate two psychophysical contrast sensitivity measurements in amblyopic patients.

Thirty five adult anisometropic amblyopes participated in this study. Psychophysical contrast sensitivity was measured for both amblyopic and fellow eyes of the participants at 1, 3 and 5 cycles per degree spatial frequencies by FrACT and Metrovision contrast sensitivity tests.

Comparison between the two tests showed more sensitivity to reduced contrast in FrACT. There were significant differences between measurements of the two tests at all spatial frequencies both in normal and amblyopic eyes (p < 0.01). Area under logarithm of contrast sensitivity function obtained from FrACT was also significantly greater (p < 0.05). Difference between the two methods rose with spatial frequency. There was a significant correlation between the two tests at most spatial frequencies.

Although both tests employ sine-wave gratings for measuring contrast sensitivity, their results are not interchangeable. Given that the two tests have significant differences in their results and have dissimilar behaviors in different conditions, we may have different interpretations from results obtained from each test for an individual observer. This means one test may confirm the possibility of presence of amblyopia while the other refuses that.