AIM: To investigate effects of intravitreal bevacizumab on ocular blood flow parameters in diabetic patients with macular edema.

METHODS: This study included 21 eyes of 21 patients. Patients who had diffuse diabetic macular edema(DME), central macular thickness(CMT)>320μm and have no ischemic macular edema or other vascular retinal disease included to this study. All patients underwent three ophthalmologic examinations before and at one day and at 4 weeks after bevacizumab 1.25mg/0.05 mL injection. Examinations including visual acuity(VA), measurement CMT by optical coherence tomography(OCT), peak systolic velocities(PSV)and end-diastolic velocities(EDV)of blood flows were measured by ultrasound imaging in the ophthalmic artery(OA), in the central retinal artery(CRA), in the nasal posterior ciliary artery(NPCA)and temporal posterior ciliary artery(TPCA). Resistive indices(RI)were automatically calculated by software of device. The velocities of blood flow before and one day after injections were compared. The values of patients before and 4 weeks after injections were compared for VA and CMT.

RESULTS: Mean best-corrected visual acuity(BCVA)was 0.88±0.21 logarithm of the minimum angle of resolution(logMAR)before and after injection was 0.54±0.19 logMAR units(P<0.01). Mean CMT decreased from 440.57±54.58 μm to 250.33±31.12(-190.24±36.00)μm. There were changes in the PSV, EDV and RI but this changes were not significant.

CONCLUSION: There was a significant improvement in VA and a decrease in CMT after bevacizumab injection. Regarding the PSV, EDV and RI, no observed significant changes in the OA, CRA, TPCA and NPCA after bevacizumab injection. Intravitreal bevacizumab injection improved VA and the CMT. However, it didn't affect blood flow velocities in diabetic patients on the OA, CRA, TPCA and NPCA.