Effect of Intravitreal Bevacizumab on the Optic Nerve Head perfusion in patients with Diabetic Macular Edema

Abstract

Purpose: To find out the effect of Intravitreal Bevacizumab on optic nerve head perfusion using Ocular Coherence Tomography Angiography (OCTA) in patients with diabetic macular edema (DME). Study Design: Interventional case series Place and duration of study: Ophthalmology Department, Mayo Hospital, Lahore from June 2018 to January 2020. Methods: In this study 57 eyes of patients fulfilling the inclusion criteria were selected from the outpatient department. After informed consent, detailed history and ocular examination was performed. Baseline OCTAwas donein all cases. The patients received intravitreal Bevacizumab (1.25mg in 0.05ml). OCTA was repeated three weeks after injection. Both the pre and post injection ONH perfusion was compared and analyzed using SPSS. Demographic chracteristics like age and gender were calculated. Paired sample t-test was applied to check the significance of difference between pre and post injection values. P-value of <0.05 was considered significant. Results:There were 16(28.1%) males and 41(71.9%) females. Mean age of the patients was 53.54±7.00 years. Pre injection blood flow was 56.11 and post injection was significamtly reduced to 52.69. The mean difference between was 3.423 and confidence interval of the difference was (2.5755-4.2701). P-value 0.000 was <0.05 whichshowed significant reduction in perfusion of ONH. Conclusion:Intravitreal Bevacizumab decreases the optic nerve head blood flow and should be used with care in patients having reduced blood flow states and also in patients with advanced glaucomatous optic neuropathy.