Vision, retinal thickness, and foveal avascular zone size after intravitreal bevacizumab for diabetic macular edema.

Introduction: To investigate three monthly intravitreal bevacizumab (IVB) injections effects in chronic diabetic macular edema (DME).

Methods: A prospective, noncomparative study in which inclusion criteria were; DME with central macular thickness (CMT) of at least 250 μm, and no treatment for diabetic retinopathy (DR) within 4 months before the first injection. All eyes received three monthly 1.25 mg IVB injections. CMT by optical coherence tomography, visual acuity (VA), foveal avascular zone (FAZ) greatest linear dimension (GLD), and area of FAZ by fundus fluorescein angiography were documented initially and 1 month after last injection. Outcomes (P<0.05 were significant) and correlations (r values) were analyzed.

Results: A total of 29 eyes of 29 patients (group 1, 19 female, 10 male), aged 60.7±6.6 years were analyzed. The patients were split into two groups; group 2 included 15 mild-to-moderate nonproliferative DR, and group 3 included 14 more-severe DR. VA gain was significant in all groups (P<0.05). Mean CMT decrease was approximately 46, 36, and 55 μm in groups 1, 2, and 3, respectively (P<0.05 only in group 1). A 0.045-mm2 increase in FAZ area was obtained in group 1 (P<0.05). In group 2, an increase in GLD and area of FAZ was 0.048 mm and 0.058 mm2, respectively (P<0.05), whereas in group 3, FAZ enlargement was nonsignificant. VA and CMT were significantly correlated (r values=0.5-0.6), except for the final VA-final CMT in group 2. FAZ dimensions and other parameters (VA and CMT) were noncorrelated.

Conclusion: According to the authors' short-term results, three monthly IVB injections can be used for chronic DME regardless of VA, CMT, or FAZ dimensions, despite the FAZ enlargement encountered, especially in cases with milder DR.