Efficacy and safety of one intravitreal injection of bevacizumab in diabetic macular oedema

Purpose: To assess the efficacy, duration of effect and safety of one intravitreal injection of bevacizumab in diabetic macular oedema (DMO). Methods: Bevacizumab (1 mg/0.04 ml) was injected intravitreally into eyes with DMO (29 with and nine without previous treatments). Best corrected visual acuity (BCVA), intraocular pressure and central retinal thickness (CRT) were measured; slit-lamp examination, macular biomicroscopy, optical coherence tomography and fluorescein angiography were performed before and at 2-4, 8 and 12 weeks post-injection. Best corrected VA and CRT were analysed in both groups. Results: In the non-pretreated group, mean BCVA improved from 0.76 +/- 0.33 (baseline) to 0.57 +/- 0.30 and 0.54 +/- 0.27 at 2-4 weeks and 8 weeks post-injection, respectively (p = 0.02, p = 0.014, paired t-test). Mean CRT decreased from 632.4 +/- 196.0 mu m (baseline) to 392.3 +/- 113.6 mu m and 370.4 +/- 141.7 mu m at the same time-points, respectively (p = 0.01, p = 0.01). There was no difference in BCVA or CRT at 12 weeks. In the pretreated group, mean BCVA improved from 0.62 +/- 0.30 (baseline) to 0.53 +/- 0.33 at 2-4 weeks post-injection (p = 0.01), and mean CRT decreased from 583.9 +/- 180.7 mu m (baseline) to 404.1 +/- 197.9 mu m at 2-4 weeks post-injection (p < 0.001). Mean BCVA was unchanged at 8 weeks and 12 weeks post-injection, although mean CRT remained lower at 8 weeks (p = 0.004). No ocular or systemic side-effects developed during follow-up. Conclusions: One intravitreal injection of bevacizumab for DMO seems to be effective and safe in both eyes that have been treated previously and eyes that have not. The therapeutic effect is temporary and repeat treatment may be needed.