OBJECTIVE: To examine the sensitivity of mf-ERG at measuring changes in retinal electrical activity in response to Avastin (bevacizumab) treatment for age-related Macula degeneration (ARMD).
METHODS: Nine subjects with exudative ARMD, not previously treated with bevacizumab in the investigated eye, underwent pretreatment testing with mf-ERG and intravenous fluorescein angiography (IVFA). A second mf-ERG test was conducted post-treatment. The P1 response amplitudes were examined for the hexagons corresponding to areas of pathology on the IVFA. Inter-test variability was accounted for by examining areas without pathology. Aggregate responses were also generated for central and lesion associated responses.
RESULTS: Changes in P1 response amplitude correlated with changes in visual acuity (R2>0.96). An improvement in Snellen visual acuity correlated with a significant improvement in P1 response amplitude from lesion associated recordings (p<0.03). Changes in P1 response amplitudes were not observed when aggregate responses were generated.
CONCLUSION: This study represents a novel method for assessing an improvement of mf-ERG responses. This is the first study to demonstrate a statistically significant change in retinal electrical activity post-bevacizumab in patients with ARMD. This study demonstrates a method for utilizing mf-ERG to assess changes in retinal electrical activity and to assess the effectiveness of treatments such as bevacizumab.