Multifocal Electroretinography and Spectral-Domain Optical Coherence Tomography in Macula-Off Rhegmatogenous Retinal Detachment

Abstract

Purpose:To analyze the temporal trends in structural changes using spectral-domain optical coherence tomography and functional changes using multifocal electroretinogram after rhegmatogenous retinal detachment surgery.Methods: This prospective cohort study enrolled 69 patients with macula-off rhegmatogenous retinal detachment who underwent successful surgery. Early Treatment Diabetic Retinopathy Study visual acuity, multifocal electroretinogram evaluation of the central 5°, and spectral-domain optical coherence tomography were recorded at 1, 3, 6, and 12 months (M) after surgery. The fellow eye served as the control group for multifocal electroretinogram parameters.Results: Between M1 and M12, visual acuity improved from 64 to 75 letters (P = 0.001) and implicit time of N1 decreased from 27.8 to 25.2 milliseconds (P = 0.001), whereas the other parameters did not vary significantly. Amplitude and implicit time values did not reach normal values at M12. Alterations of the ellipsoid zone and the external limiting membrane decreased over time (P = 0.001). P1 implicit time correlated independently with the alteration of the external limiting membrane (P = 0.007).Conclusion: Foveal wave amplitudes remain lower than normal values after successful surgery of rhegmatogenous retinal detachment, whereas anatomical improvement was found for outer retinal abnormalities and subretinal edema fluid. Retinal recovery improves N1 implicit time over time. Disruption of external limiting membrane seems to be predictive of increased P1 implicit time.

Electroretinogram changes before and after silicone oil removal in eyes with macula-off rhegmatogenous retinal detachment

“…ERG responses may gradually decrease if SO remains in the vitreous cavity for a long time [46]. We should consider that photoreceptor recovery after retinal reattachment requires approximately 4 weeks [17,[47][48][49]. In our series, the SO tamponade duration was shorter than 9 months but significantly longer than 4 weeks (mean [SD]: 147.8 [34.9] days).…”

“…A few studies have demonstrated early deterioration with a lasting effect on ERG amplitude after SO injection [17,20,35]. A study suggested retinal degeneration or a nerve impulse insulating effect due to the presence of intravitreal SO [20].…”

“…Only a few studies have evaluated electroretinographic changes following retinal detachment repair with temporary SO tamponade for any vitreoretinal pathology [17][18][19][20], although with contradictory theories explaining their results. According to this limited body of evidence, pars plana vitrectomy (PPV) with SO injection may adversely affect electroretinographically determined responses of the retina [17][18][19]. A hypothesis states that SO itself may cause retinal dysfunction characterized by a decline in electrophysiological responses [17][18][19][20].…”

“…According to this limited body of evidence, pars plana vitrectomy (PPV) with SO injection may adversely affect electroretinographically determined responses of the retina [17][18][19]. A hypothesis states that SO itself may cause retinal dysfunction characterized by a decline in electrophysiological responses [17][18][19][20]. Other explanations regarding reduced electroretinographic responses include insulating properties of the SO itself, surgical intervention per se, or potential for retinal degeneration [17][18][19][20].…”

“…A hypothesis states that SO itself may cause retinal dysfunction characterized by a decline in electrophysiological responses [17][18][19][20]. Other explanations regarding reduced electroretinographic responses include insulating properties of the SO itself, surgical intervention per se, or potential for retinal degeneration [17][18][19][20]. To date, no study has investigated the effects of SO on electrical retinal response density using ff ERG or mf ERG exclusively in the eyes with macula-off rhegmatogenous retinal detachment (RRD) that underwent a single successful three-port PPV with SO tamponade.…”