Intravitreal erythropoietin injection for the treatment of non-arteritic anterior ischaemic optic neuropathy

Aim: To evaluate the effect of intravitreal injection of erythropoietin for the treatment of non-arteritic anterior ischaemic optic neuropathy (NAION). Methods: In this prospective interventional case series, 31 eyes of 31 patients with NAION were included. Patients received intravitreal injection of 2000 unit (0.2 cm³) of erythropoietin within 1 month of the onset of the disease. Visual acuity and visual field were recorded before injections and 1 week, 1 month, 3 months and 6 months after the injections. Results: The mean duration of symptoms before injections was 11.2±5.5 days. Six months after injections, visual acuity improved in 27 eyes (87%), and 17 eyes (54.8%) had ≥3 lines of visual improvement. The mean preinjection visual acuity was 1.01±0.88 logMAR and 0.58±0.58 logMAR (p<0.001) at last follow-up. Visual acuity improvement occurred in 61.2% of patients within the first month. It followed a biphasic pattern in which there was continuous improvement up to 3 months and then started to deteriorate, although it remained significantly better than baseline until the last follow-up. No patient lost any lines of visual acuity compared with the baseline values. The mean of mean deviations of visual field was -19.6±5.7 dB at baseline and -18.6±6.3 dB (p=0.6) at last follow-up. Conclusions: Intravitreal injection of erythropoietin may be safe and effective in the treatment of NAION. The effect may last for a few months and then decline.