To study the correlation of mean macular thickness using optical coherence tomography with distant and near visual acuity in patients of diabetic maculopathy
DOI:
https://doi.org/10.18203/2320-6012.ijrms20180605Keywords:
Diabetic maculopathy, Macular thickness, Optical coherence tomographyAbstract
Background: to study the correlation of mean macular thickness using optical coherence tomography with distant and near visual acuity in patients of diabetic maculopathy.
Methods: A prospective, single centre study was conducted on 50 eyes of diabetic patients, with Diabetic Retinopathy with CSME in which patients macular thickness was measured on Ocular Coherence Tomography using fast macular thickness scan. The unaided and best corrected visual acuity was measured in all patients using Snellens distant vision and Jaggers near vision charts.
Results: A linear correlation between the OCT measured macular thickness and both the distance visual acuity and the near visual acuity. That means that for a given level of macular thickness, we can predict visual acuity for it. In our series correlation coefficient was 0.921 for distance visual acuity and 0.899 for near visual acuity. Although the correlation value is high in our study, we did find a range of visual acuities for a given range of macular thickness. For every 100 micron change in mean macular thickness, best corrected visual acuity (BCVA) changed 0.3 LogMAR units, for distance as well as for near.
Conclusions: Macular thickness and visual acuities (distance as well as near) are strongly correlated but there can be variations. And a wide range of visual acuities is possible for a given degree of macular edema. Macular thickness though a strong predictor of visual acuity; other factors might also play a role in determining visual acuity for a particular patient.
References
Kahn HA and Hiller R. Blindness caused by diabetic retinopathy. Am J Ophthalmol. 1974;78(1):58-67.
Ramachandra A, Jali MV, Mohan V, Snahlata C, Vishwanathan M. High prevalence of diabetes in an urban population of south India. Brit M J. 1988;297(6648):587-90.
Wild S, Roglic G, Green A. Global prevalence of diabetes, estimates for the year 2000 and projections for 2030. Diabetes Care. 2004;27(5):1047-53.
Gupta V, Gupta A, Dogra MR, Singh R. Diabetic Retinopathy Atlas and text. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd. 2007;75-88.
American Diabetes Association. Standards of medical care in diabetes 2006. Diabetes care 2006;29(Suppl 1):S4-42.
Moss SE, Klein R and Klein BE. Ten-year incidence of visual loss In a diabetic population. Ophthalmol. 1994;101(6):1061-70.
Pardianto G. "Understanding diabetic retinopathy". Mimbar Ilmiah Oftalmologi Indonesia. 2005;2:65-6.
Arend O, Wolf S and Jung F. Retinal microcirculation in patients with Diabetes Mellitus; Dynamic and Morphological analysis of perifoveal capillary network. Br. J. Ophthalmol. 1991;75(9):514-8.