Association between individual retinal layer thickness and visual acuity in patients with epiretinal membrane: a pilot study

Jing Zou; Wei Tan; Wenlong Huang; Kangcheng Liu; Fangling Li; Huizhuo Xu

doi:10.7717/peerj.9481

Association between individual retinal layer thickness and visual acuity in patients with epiretinal membrane: a pilot study

PeerJ. 2020 Jul 10:8:e9481. doi: 10.7717/peerj.9481. eCollection 2020.

Authors

Jing Zou^#^{1

2}, Wei Tan^#^{1

2}, Wenlong Huang^{1

2}, Kangcheng Liu^{1

2}, Fangling Li^{1

2}, Huizhuo Xu^{1

2}

Affiliations

¹ Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan Province, China.
² Hunan Key Laboratory of Ophthalmology, Changsha, Hunan Province, China.

^# Contributed equally.

Abstract

Purpose: We investigated the correlation between visual acuity (VA) and individual retinal layer thickness in the foveal, parafoveal, and perifoveal regions of patients with an idiopathic epiretinal membrane (ERM).

Methods: One hundred and five subjects presenting with unilateral idiopathic ERM were included in this study. We segmented each patient's optical coherence tomography (OCT) image into seven layers and calculated the mean layer thickness in the foveal, parafoveal, and perifoveal regions using the Iowa Reference Algorithm. In 105 patients with ERM, we detected correlations between their macular regions' individual retinal layer thickness and their best corrected VA. Thirty-one of the 105 patients with ERM underwent vitrectomy and completed six months of follow-up. We then compared the 31 surgical patients' preoperative and postoperative individual retinal layer thickness in each macular region. Additionally, the association between preoperative individual retinal layer thickness in each macular region and VA six months post-surgery in patients with ≥ two Snellen lines of visual improvement was determined.

Results: Multiple linear regression analysis showed that the inner nuclear layer (INL) thickness in the foveal, parafoveal, and perifoveal region were all associated with VA in the 105 patients (R ² = 0.344, P < 0.001; R ² = 0.427, P < 0.001; and R ² = 0.340, P < 0.001, respectively). Thirty-one surgical patients 6 months post-surgery showed significantly decreased thicknesses (P ≤ 0.012) of the foveal INL, inner plexiform layer (IPL), and outer nuclear layer (ONL); the parafoveal retina nerve fiber layer (RNFL), IPL, INL, and ONL; and the perifoveal RNFL, IPL, INL, ganglion cell layer (GCL), outer plexiform layer (OPL), and photoreceptor layer (PRL). We found a weak correlation between postoperative VA and preoperative foveal and perifoveal RNFL thickness (r = 0.404 and r = 0.359, respectively), and a moderate correlation between postoperative VA and preoperative foveal and parafoveal INL thickness (r = 0.529 and r = 0.583, respectively) in the 31 surgical patients (P ≤ 0.047). The preoperative INL thickness in the foveal, parafoveal, and perifoveal regions showed a moderate to strong correlation (r = 0.507, 0.644, and 0.548, respectively), with postoperative VA in patients with ≥ 2 lines of visual improvement (P ≤ 0.038).

Conclusion: We detected a correlation between retinal damage and VA in the parafoveal, perifoveal, and foveal regions. Our results suggest that INL thickness in all macular regions may be a prognostic factor for postoperative VA in ERM patients.

Keywords: Epiretinal membrane; Foveal region; Parafoveal region; Perifoveal region; Retinal layer thickness; Visual acuity.

Grants and funding

This study was supported by a grant from the Hunan Natural Science Foundation (No. 2019JJ40528) to Huizhuo Xu, and a grant from the National Natural Science Foundation of China (No.81600713) to Jing Zou. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.