Comparison of mean macular thickness using optical coherence tomography and visual acuity in diabetic retinopathy

Background: The purpose of the present study was to quantitatively assess the mean macular thickness in diabetic patients using optical coherence tomography and its correlation with visual acuity. Methods: A prospective case series study was undertaken of consecutive diabetic patients referred to a tertiary eye care centre for an eye check up from January 2003 to June 2003. One hundred and five eyes from 55 patients with varying degree of diabetes underwent optical coherence tomography examination. The study patients were divided into four groups: group I, non-proliferative diabetic retinopathy (NPDR); group II, NPDR with clinically significant macular oedema (CSME); group III, proliferative diabetic retinopathy (PDR); and group IV, PDR with CSME. Results: The mean macular thickness of the entire group was 256.0 +/- 129.7 mu m. A positive correlation (r = 0.424, P < 0.0001) was evident between mean macular thickness and visual acuity. Conclusion: Optical coherence tomography is a useful tool for objectively monitoring macular thickness in patients with diabetic retinopathy. Mean macular thickness correlates with visual acuity.