Background: To evaluate the long-term outcome of an OCT-guided reinjection scheme for bevacizumab treatment of macular edema (ME) due to retinal vein occlusion.
Methods: Patients with persistent ME (>250 microm) due to central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) received intravitreal bevacizumab 2.5 mg/0.1 ml. Visual acuity (ETDRS), ophthalmic examination and OCT were performed at baseline and at 6- to 8-week intervals. Reinjections were only performed if OCT showed persistent or recurrent ME.
Results: Sixty-one patients with a minimum follow-up of 25 weeks were included in this analysis. Mean follow-up was 60 +/- 29 wks. In CRVO patients, central retinal thickness (CRT) decreased from 748 +/- 265 microm to 372 +/- 224 microm (p < 0.001) and visual acuity (VA) improved by 1.9 +/- 3.2 lines. In BRVO patients, mean CRT decreased from 601 +/- 206 microm to 386 +/- 178 microm (p < 0.001) and VA improved by 1.8 +/- 2.6 lines. Thirty-three percent of CRVO and 15% of BRVO patients did not show a ME recurrence for > or =25 wks at last visit. Thirty-seven percent of CRVO and 50% of BRVO patients suffered recurrences of ME within the last 25 wks, whereas 30% of CRVO and 35% of BRVO patients did not achieve a complete resolution of ME at any follow-up visit after receiving a minimum of three injections. CRVO patients with dry interval of > or =25 weeks at last visit were significantly younger, had a thinner CRT at baseline and more often had a complete resolution of ME after the first injection. In CRVO and BRVO, final VA was correlated significantly with initial VA, patients' age and final CRT. Change of VA was correlated with change of CRT in BRVO.
Conclusions: Patients with retinal vein occlusion benefit from treatment with bevacizumab. Favourable long-term results without necessity of further injections were achieved in 33% and 15% of CRVO and BRVO patients respectively. The remaining patients needed repeated injections to treat ME recurrences. However, one third of the CRVO/BRVO patients did not improve in VA, and further injections might be discontinued in these patients.