The macular area and central posterior pole can be assessed on a more localised level by the PERG and mfERG, respectively.
Pattern-VEPs have similar waveforms to PERGs and mfERGs with a negative trough (N75) followed by a positive peak (P100) and a final negative peak (N135).
mfERG (VERIS-EDI System, Califronia, USA) was not conducted until 1 month after surgery for the sake of avoiding infection and was monitored during the following visits.
One-hundred and three hexagonal stimulus elements that scaled concentrically and covered the central 50[degrees] of the fundus were applied to each patient when examine mfERG.
BCVAs and RD of the central hexagon and the central seven hexagons on mfERG at different time points (baseline, 1 and 3 months after surgery) were compared pairwisely by post-hoc tests after analysis of variance.
Encouragingly and in consistency with the reconstruction process of the foveal microstructure, all patients except one (7/8) showed incremental improvements of visual function (both in BCVA and mfERG responses) over time during the first 3 months after surgery [Figure 2].
BCVA neither “significantly” correlated with mfERG RD of fovea nor with RD of the central seven hexagons at each evaluation time point [Figure 5], despite their similar incremental tendency after surgery [Figure 4].
Unintended injury of the nerve fiber layer during ILM peeling, however, might compromise recovery of BCVA and mfERG [Figure 3].
Although both BCVA and mfERG responses improved incrementally after surgery [Figure 4], they were not found to be statistically correlated at each evaluation time point of our short-term observation [Figure 5] as well as in previous longer term studies concerning conventional surgical technique (just ILM peeling but without inverting) in treatment of MHs.