Correlations between optical coherence tomography measurement of macular thickness and visual acuity after cataract extraction

Abstract

Purpose: To investigate correlations between optical coherence tomography macular thickness measurements and visual acuity after cataract surgery.

Methods: Sixty-two patients underwent routine cataract surgery as part of a randomized clinical trial of oral Cox-2 inhibitor prophylaxis of cystoid macular oedema. Optical coherence tomography was used to quantify several parameters of macular thickness. Optical coherence tomography measurements were obtained before surgery, day one, week two and week six after surgery. These measurements were then correlated with logMAR best-corrected visual acuity.

Results: Optical coherence tomography macular thickness parameters increased after surgery by up to 20%. A significant correlation was identified between foveal minimum macular thickness and best-corrected visual acuity at day one and week six after surgery. Other macular parameters failed to show any significant correlation. At day one and week six, the 10 patients with greatest macular thickness had significantly lower visual acuity than the other patients.

Conclusion: In this study routine cataract surgery caused an increase in macular thickness. Some significant positive correlations between macular thickness and best-corrected visual acuity were found, although not for all parameters or time points. There may be a threshold relationship between degree of foveal anatomic change and significant loss of visual acuity.