MULTIFOCAL ELECTRORETINOGRAPHY AND SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY IN MACULA-OFF RHEGMATOGENOUS RETINAL DETACHMENT: A Prospective Cohort Study

Correlation between multifocal electroretinogram and optical coherence tomography findings with visual acuity after vitrectomy surgery for retinal detachment: an observational study

BACKGROUND

Despite the marked increase in the anatomical success rates of macula-off rhegmatogenous retinal detachment (RRD) surgery, patients may still complain about unsatisfactory visual outcome. This study aims to correlate the postoperative corrected distance visual acuity (CDVA) with the mf-ERG (multifocal electroretinogram) and OCT (optical coherence tomography) findings following vitrectomy surgery for RRD.

PATIENTS AND METHODS

This retrospective observational study included 40 eyes of 40 patients who underwent successful vitrectomy surgery for macula-off RRD. CDVA, mf-ERG amplitudes, mf-ERG latencies, the central macular thickness (CMT) and the integrity of the inner segment/outer segment (IS/OS) junction assessed by OCT, were evaluated 6 months postoperatively. The correlations between CDVA with mf-ERG amplitudes, mf-ERG latencies, central macular thickness, and IS/OS junction integrity were analyzed.

RESULTS

There was a statistically significant moderate positive correlation between CDVA of the studied eyes with mf-ERG amplitudes of N1, P1 and N2 in ring 1 (P = 0.008; P < 0.001 and P = 0.004, respectively), CMT (P < 0.001), and the integrity of IS/OS junction (P < 0.001). There was no significant correlation between CDVA and mf-ERG latencies in ring 1 (P > 0.05). Linear regression analysis revealed that CDVA was significantly associated with mf-ERG amplitudes and the IS/OS junction integrity. In addition, there was a strong positive correlation between mf-ERG amplitudes in ring 1 and the IS/OS junction integrity.

CONCLUSIONS

The integrated interpretation of postoperative CDVA, multifocal ERG parameters, and OCT findings provides useful information about functional visual recovery and retinal microstructural changes following vitrectomy for macula-off RRD surgery. The positive correlation between the IS/OS junction integrity and the mf-ERG amplitudes was stronger than the correlation between the IS/OS junction integrity and CDVA suggesting that mf-ERG may be superior to CDVA in reflecting the extent of microstructural damage in the photoreceptor layer.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT05993208. Registered 15 August 2023 - Retrospectively registered, https://classic.

CLINICALTRIALS

gov/ct2/show/NCT05993208 .

How should we report the foveal status in eyes with "macula-off" retinal detachment?

Whilst pre- and postoperative multimodal imaging technologies including optical coherence tomography (OCT) have investigated the morphological correlates of worsened visual outcomes in rhegmatogenous retinal detachment (RRD) with foveal involvement, the nomenclature has adhered to the traditional ophthalmoscopy-based and rather vague term "macula-off". This article appraises the current literature with regard to the preoperative assessment and nomenclature of the foveal status in macula involving retinal detachment (MIRD). A literature review of recent publications assessing functional or morphological outcomes in MIRD was conducted, using the search terms "fovea-off" or "macula-off". The search date was April 28^th, 2021. Original studies in English language were included. Case reports, review articles or letters were excluded. Forty relevant articles (range of publication dates: July 29^th, 2020 - April 18^th, 2021) were reviewed to assess the diagnostic modalities used, morphological parameters assessed, and any specific nomenclature introduced to specify the extent of macular detachment. The results suggest widespread variability and inconsistencies with regard to the preoperative assessment, diagnostic modalities and nomenclature used to describe the foveal status in eyes with RRD termed "macula-off". The extent of macular detachment may be classified by a wide range of morphological parameters, including the height of foveal detachment and the ETDRS grid as overlay tool in OCT devices. There is a scientific and clinical need for an updated nomenclature for eyes with "macula-off" RRD. Preoperative OCT findings should be reported on a regular and standardized basis in order to establish a consensus how to report the foveal status in eyes with MIRD.