Contrast sensitivity measurement with 2 contrast sensitivity tests in normal eyes and eyes with cataract

Purpose: To assess the reliability of and correlation between 2 contrast sensitivity tests in normal eyes and eyes with cataract.

Setting: Department of Ophthalmology, Yonsei University Hospital, Seoul, Korea.

Methods: The Vision Contrast Test System (wall-chart test) and Optec 6500 system (view-in test) were used to measure contrast sensitivity in normal eyes at 2 visits separated by 2 weeks and in eyes with cataract before and 2 months after cataract surgery. The test-retest reliability and correlation were calculated by the intraclass correlation coefficient (ICC), coefficient of repeatability (COR), and 95% range of difference using the Bland-Altman method.

Results: The study evaluated 40 normal eyes of 20 subjects and 44 eyes of 38 cataract patients. The repeatability of the 2 test methods was generally acceptable. The view-in test performed better than the wall-chart test in the ICC analysis (0.85 versus 0.65) but not in the COR analysis (+/-0.20 log versus +/-0.27 log). Correlation between the 2 tests was poor in both groups of eyes. The ceiling effect was greater with the wall-chart test. The floor effect occurred mainly in patients with cataract, in which it was greater preoperatively than postoperatively; at high frequency; and with the view-in test.

Conclusion: Based on the ceiling and floor effect, the view-in test is better for detecting subtle contrast sensitivity changes in normal or near-normal eyes and the wall-chart test is useful in eyes with compromised vision.

Financial disclosure: No author has a financial or proprietary interest in any material or method mentioned.