Analysis of multifocal electroretinography implicit times in the prediction of macular hole formation

Abstract Purpose Our aim was to investigate the predictive role of multifocal electroretinography (mfERG) by analyzing the implicit time changes in the fellow eye of patients with unilateral macular hole. Methods 80 eyes of 40 patients with unilateral macular hole were examined by mfERG (RetiScan, Roland Consult, Germany). Ring ratios of the multifocal electroretinograms were calculated by correlating the central rings’ implicit time with that of the peripheral ones (T1/T2, T1/T3, T1/T4 and T1/T5). After vitreoretinal surgery, during the follow‐up period of 24 months, in 13 of 40 cases macular hole formation was detected in the previously intact fellow eye by optical coherence tomography. Patients were divided into two groups according to this. The implicit time ring ratios of the two groups were compared. Results Surprisingly, although the implicit times showed no significant difference in the two groups, the ratios T1/T2, T1/T3, T1/T4 and T1/T5 were significantly lower in the eyes that later developed macular hole (1.08, 1.12, 1.14, 1.16) than those which remained intact (1.01, 1.03, 1.05, 1.07, respectively; p<0,05). Conclusion By analyzing the mfERG implicit time, using ring ratios seems to be a more sensitive method in predicting macular hole formation in the fellow eye, than analyzing the implicit times alone. Lower values might forecast propensity for subsequent macular holes. These patients may require stricter follow‐up.