Comparison of optical coherence tomography angiographic findings with pre-injection values in patients used with intravitreal bevacizumab injection for diabetic macular edema

Objective: In our study, ACD, optical coherence tomography (OCT), visual evoked potentials (VEP) and macula and disc optical coherence tomography angiography (OCT-A) imaging methods in the acute period before and after intravitreal bevacizumab injection used in the treatment of diabetic macular edema (DME) were evaluated. We aimed to reveal the retinal anatomical, functional and vascular changes shown and to determine whether these changes correlate with visual acuity and other results. Materials and Methods: In our study, which included 40 eyes of 40 patients with a diagnosis of diabetic macular edema who applied to Balıkesir University Ophthalmology Clinic, who had not received any treatment before, a single intravitreal injection of bevacizumab was administered to the patients. Intraocular pressures and ACD of the patients were recorded before the treatment and at the first week and first month; Fundus fluorescein angiography, optical coherence tomography, VEP and macula and disc optic coherence tomography angiography were performed. Results: No statistically significant difference was observed in terms of the patients' initial age, gender, LogMAR, and mean intraocular pressure values. (p>0.05) While no statistically significant change was observed in the patients' VEP values at the 1st week before the injection and after 1 dose of intravitreal bevacizumab treatment, at the 1st month. A statistically significant difference was detected in VEP values (n75ms, n75uv, p100ms, p100uv). (p<0.001 in all) When the data obtained with Macula and Disc OCT-A were examined, a statistically significant difference was found in the comparison of the pre-treatment FAZ area and Disc vascular density with the 1st week and 1st month values. (p<0.001) FAZ in the hyperacute and acute phases It was shown that the area expanded and the vascular densities in the disc decreased, and there was a further improvement in the average VEP voltage and latency values of the patients after treatment. Conclusion: In summary, it is seen that there are significant improvements in OCT-A findings showing anatomical and structural integrity and VEP findings showing functional state of vision, together with an increase in visual acuity in patients who received intravitreal bevacizumab injection in DME. It was found that there is a correlation between anatomical recovery and functional recovery and it can be predicted by OCT-A findings. Keywords: Diabetic macular edema, bevacizumab, optical coherence tomography angiography, visual evoked potentials