PROPHYLAXIS OF MACULAR EDEMA WITH PEROPERATIVE INTRAVITREAL BEVACIZUMAB IN PATIENTS WITH DIABETIC RETINOPATHY UNDERGOING PHACOEMULSIFICATION; A RANDOMIZED CONTROLLED TRIAL   DR SIDRA JABEEN PGT OPHTHALMOLOGY HOLY FAMILY HOSPITAL

Introduction: Macular edema (ME) is an abnormal thickening of the macula due to accumulation of excess fluid in the extracellular space of the retina2. leading cause of irreversible vision loss in diabetic retinopathy3. DME after cataract surgery can difficult visual improvement3. Eyes with heavy macular leakage have significantly higher VEGF concentration as compared to eyes with less leakage. Therefore anti-VEGF treatments can be considered as an adjunctive treatment for DME4.  Bevacizumab (avastin) is a full-length antibody that inhibits all isoforms of the VEGF-A family A study showed that Intravitreal administration of 1.25 mg bevacizumab at the time of cataract surgery was safe and effective in preventing the progression of DR and diabetic maculopathy in patients with cataract and DR1.

References: Salehi A, Beni AN, Razmjoo H, Beni ZN. Phacoemulcification with intravitreal bevacizumab injection in patients with cataract and coexisting diabetic retinopathy: prospective randomized study. J Ocul Pharmacol Ther. 2012 Jun;28(3):212-8.(also used for calculation of sample size) Qazi HA. Intravitreal administration of 1.25 mg bevacizumab at the time of cataract surgery was safe and effective in preventing the progression of DR and diabetic maculopathy in patients with cataract and DR. J Res Med Sci. 2012 Dec; 17(12): 1180–1187. Chae JB, Joe SG, Yang SJ, Lee JY, Sung KR, Kim JY, Kim JG, Yoon YH. Effect of combined cataract surgery and ranibizumab injection in postoperative macular edema in nonproliferative diabetic retinopathy. Retina. 2014 Jan; 34(1):149-56. Ateeq A, Tahir MA, Cheema A, Dahri A, Tareen S. Intravitreal injection of Bevacizumab in diabetic macular edema. Pak J Med Sci 2014; Vol. 30 No. 6

Rationale of my study is to determine effectiveness of peroperative intravitreal bevacizumab in prophylaxis of macular edema in patients with mild to moderate non proliferative diabetic retinopathy undergoing phacoemulsification so as to improve visual outcomes.

Objective: To compare the occurrence of macular edema in patients of mild to moderate non-proliferative diabetic retinopathy (NPDR) receiving peroperative Intravitreal bevacizumab, with occurrence of macular edema in controls, at completion of first and third month after phacoemulsification cataract surgery.

Hypothesis: The Proportion of patients with occurrence of macular edema at 1st and 3rd months post phacoemulsification cataract surgery will not be the same in patients receiving per-operative Intravitreal bevacizumab and in the controls.

Study design: Randomized controlled trial Setting: Ophthalmology Department Holy Family Hospital, Rawalpindi. Duration of study: study will be completed within 06 months of acceptance of synopsis. Sampling technique: nonprobability consecutive sampling

Inclusion criteria: Exclusion criteria: Age 50-70 yrs Both genders. Mild to moderate NPDR Visually significant cataract. Macular edema absent at baseline preoperatively measured through OCT (CMT <250µm) Exclusion criteria: Previous diabetic macular edema; treated or not. Ischemic maculopathy as shown on fluorescein fundus angiography (FFA) . Proliferative diabetic retinopathy. Any complication during surgery. Any other ocular pathology likely to reduce vision e.g., hypertensive retinopathy, retinal vein occlusion, ocular surface disease. Recent stroke or myocardial infarction.

Sample size: Minimally required sample size in each study group according to WHO sample size calculator n = 27; 10% is added to compensate attrition in each group.

Data collection technique: After taking approval from RES, individuals meeting the selection criteria will be enrolled in the study after taking written informed consent. All participants will be randomly assigned in a 1:1 ratio to receive an intravitreal injection of bevacizumab (1.25mg in 0.05ml) at the end of cataract surgery(study group) or not (control group) through simple random sampling technique. A complete ophthalmologic examination will be performed baseline (before the surgery) and at completion of 1st and 3rd month after cataract surgery by the same researcher in all cases. The researcher will not be aware of the allocation of the patients to the study groups. Patients will undergo standard cataract surgery (phacoemulsification and monofocal intraocular lens (IOL) implantation). All surgeries and intravitreal injections will be performed by the same surgeon.

Data analysis All the data will be entered and analyzed using statistical package of social sciences SPSS. To compare the occurrence of macular edema at completion of first and third month in both study groups, Pearson’s chi-square test at 5% level of significance will be applied. A p- value p<0.05 will be considered as statistically significant

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