Abstract
Purpose: :
To report multifocal electroretinography (mfERG) and visual acuity (VA) results in neovascular age-related macular degeneration (nAMD) patients treated with ranibizumab. Furthermore, to compare two different mfERG recording lengths.
Methods: :
Twenty-four eyes of 24 treatment-naive patients received 3 loading dose injections with 0.5 mg ranibizumab with 4 weeks intervals and were treated "as needed" thereafter. We measured mfERG (Veris Science 5.2.3X) P1 amplitude and implicit time of 103 hexagons in 6 concentric rings and ETDRS (Early Treatment Diabetic Retinopathy Study) VA at baseline, 1 and 4 weeks, 3 and 6 months. At 6 months the mfERG was recorded twice to compare the 4.30 and 9 minutes protocol.
Results: :
Mean mfERG P1 amplitudes did not show statistically significant changes. P1 implicit times increased from baseline in ring 4 at 1 week (p<0.05), in ring 5 at 1 and 4 weeks (p<0.01/0.05) and in ring 6 at all follow-up points (p<0.01). Mean ±SD VA improved up until 3 months from 58.3 ±15.9 ETDRS letters at baseline to 62.4 ±15.9 letters at 3 months (p=0.027). At 6 months mean VA remained stable compared to baseline (57.3 ±19.8 letters, p=0.88). No statistically significant difference was seen in P1 amplitudes or implicit times between mfERG recording time of 4.30 and 9 minutes.
Conclusions: :
Improved VA was seen up until 3 months. The elongated mfERG implicit times may indicate changes in retinal function however, not seen consistently in all rings.
Keywords: age-related macular degeneration • electroretinography: clinical • drug toxicity/drug effects