Calculation of intraocular lens power and to determine the relationship between ocular biometry and severity of diabetic retinopathy in patients with type II diabetes mellitus

Abstract

Purpose: To calculate the intraocular lens power and to determine the relationship between ocular biometry and severity of diabetic retinopathy (DR) in patients with type II diabetes mellitus. Methods: The study group included 150 type II diabetic subjects with DR. The control group consisted of 150 type II diabetic subjects having no DR. Axial length (AL), corneal power, and anterior chamber depth were measured using LenStar. DR and diabetic macular edema were classified according to International DR Classification. Crystalline lens power was calculated using Barrett Universal II formula. AL to corneal radius ratio was calculated. Chi-square test was used for categorical variables. Results: In multivariate logistic models adjusting for age, sex, glycosylated hemoglobin, duration of diabetes, Mean age of patients in the study group was 62.45 ± 4.85 years, whereas in the control group, it was 63.37 ± 7.29 years. Of the eyes with DR, 117, 76, 69, and 38 had mild NPDR, moderate NPDR, severe NPDR, and PDR, respectively. The difference in the mean duration of diabetes mellitus and glycosylated hemoglobin in both study and control groups was found to be statistically significant. A progressive decrease in the mean AL and the anterior chamber depth was observed with increasing severity of DR, and difference was statistically significant. There was a progressive increase in intraocular lens power with increasing severity of DR, and difference was found to be statistically significant. Conclusion: In persons with diabetes mellitus, globe elongation plays quite an important role in protective effects against DR, with contribution from intraocular lens power and other refractive components.