COMPARATIVE EFFICACY OF LASER PHOTOCOAGULATION MONOTHERAPY, INTRAVITREAL BEVACIZUMAB MONOTHERAPY AND COMBINED LASER PHOTOCOAGULATION AND INTRAVITREAL BEVACIZUMAB THERAPY IN THE MANAGEMENT OF MACULAR OEDEMA ≥ 350 µm IN NONISCHAEMIC, NON-PROLIFERATIVE DIABETIC RETINOPATHY IN TYPE 2 DIABETES MELLITUS

Abstract

BACKGROUND The purpose of this study is to assess efficacy of laser photocoagulation monotherapy, intravitreal Bevacizumab monotherapy and combined therapy (laser photocoagulation and intravitreal Bevacizumab) on the basis of mean average change in BCVA and changes in macular thickness over 6 months in DME ≥ 350 µm. This is to identify the best treatment option in Non-Proliferative Diabetic Retinopathy (NPDR) with macular thickness ≥ 350 µm in type 2 diabetic retinopathy patients. Design-An open label, randomised, parallel group, comparative trial. MATERIALS AND METHODS In this study, Best Corrected Visual Acuity (BCVA) and macular thickness (CFT) was compared before and after modified macular grid laser monotherapy, intravitreal Bevacizumab injection monotherapy and combined therapy in patients with macular oedema with thickness ≥ 350 µm measured with spectral domain OCT. One hundred and twenty (120) newly diagnosed eyes of NPDR with macular oedema (40 patients in each group, age and sex matched) attending retina clinic of Regional Institute of Ophthalmology, Kolkata, over a period of one year (01/09/2013 to 31/08/2014) were included in this study. Patients having bilateral macular oedema were treated with one group of therapy in one eye and another group of therapy in other eye. We have considered newly diagnosed non-ischaemic non-proliferative diabetic retinopathy eyes with macular oedema of ≥ 350 µm. RESULTS Mean CFT at the start of the treatment, i.e. the baseline was statistically insignificant in between and within the three groups, but it became significant at 1 month (p = 0.0001), at 3 months (p = 0.0001) and at 6 months (p = 0.0001) using One-Way ANOVA. Therefore, there is significant difference in the improvement achieved at 1 month, 3 months and 6 months in CMT within the three groups and also between the three groups. Mean BCVA at the start of the treatment, i.e. the baseline was statistically insignificant in between and within the three groups, but it became significant at 1 month (p = 0.001), at 3 months (p = 0.0001) and at 6 months (p = 0.0001) using One-Way ANOVA. Therefore, there is significant difference in the improvement achieved at 1 month, 3 months and 6 months in BCVA. CONCLUSION This parallel group comparative trial has shown that Intravitreal Bevacizumab is most effective in reducing the central macular thickness followed by combined treatment and then modified grid laser treatment. This study has also shown that Intravitreal Bevacizumab is most effective in improving the best corrected visual acuity.