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Original Study

Longitudinal Change in Retinal Nerve Fiber Layer Thickness and Its Association With Central Retinal Sensitivity After Epiretinal Membrane Surgery

Sato, Tatsuhiko MD, PhD; Yamauchi-Mori, Reina COT; Yamamoto, Junya COT; Hayashi, Ken MD, PhD

Author Information
Asia-Pacific Journal of Ophthalmology: May-June 2022 - Volume 11 - Issue 3 - p 279-286
doi: 10.1097/APO.0000000000000523
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Abstract

Epiretinal membrane (ERM) is a common macular disorder, especially in older populations. Vitrectomy is the gold standard treatment for ERM, in which internal limiting membrane (ILM) peeling is often performed concurrently to completely remove the ERM and/or prevent recurrence.1–3

Reports about the effects of surgery on retinal sensitivity in eyes with ERM are conflicting. Tsuchiya et al4 demonstrated that vitrectomy with ILM peeling for ERM might cause a deterioration of sensitivity in the central macula in glaucomatous eyes but not in eyes without glaucoma. In contrast, Yoshida et al5 found no visual field deterioration after vitrectomy with ILM peeling for ERM in glaucomatous eyes. Blautain et al6 reported a gradual improvement in retinal sensitivity after vitrectomy with ILM peeling.

Significant correlations have been found between the thickness of the retinal ganglion cell complex and central retinal sensitivity7 and between decreased ganglion cell-inner plexiform layer thickness and decreased central retinal sensitivity after ERM surgery8; however, the measurements of inner retinal layer thickness using optical coherence tomography (OCT) in eyes with ERM are not reliable because of the high frequency of segmentation errors. In fact, the 2 abovementioned studies did not report the preoperative inner retinal thickness.7,8

Recent studies have demonstrated the localized thinning of the temporal peripapillary retinal nerve fiber layer (pRNFL) after ERM vitrectomy with ILM peeling.9–12 However, the effects of changes in pRNFL thickness on retinal function have not been fully investigated. This study aimed to investigate the longitudinal changes in pRNFL thickness after ERM surgery, examine the association between pRNFL thickness and central retinal sensitivity, and identify predictors of postoperative pRNFL thickness.

METHODS

The protocol for this prospective observational cohort study was approved by the appropriate Institutional Review Board, and the tenets of the Declaration of Helsinki were upheld. All patients eligible for enrollment were invited to participate in the study after an explanation of the nature and possible consequences of the procedures. Written informed consent was obtained from all study participants.

Participants

Patients scheduled for vitrectomy for unilateral idiopathic ERM between April 2019 and March 2020 were screened for inclusion in the study. The exclusion criteria were (1) coexisting vitreoretinal pathology that could affect visual acuity, (2) vitreoretinal pathology requiring intraoperative air/gas injection or additional surgery, (3) history of vitrectomy, and (4) follow-up for less than 12 months. The unaffected fellow eyes of the eyes with ERM were included as controls; most of them underwent cataract surgery at the same time as ERM surgery.

Comprehensive ocular examinations, including best-corrected visual acuity (BCVA), intraocular pressure (IOP) measurements using a TONOREF III (Nidek Co, Ltd, Gamagori, Japan), and OCT examinations, were performed for the eyes with ERM and the fellow eyes before and 1, 3, 6, and 12 months after surgery. Axial length was measured preoperatively using the IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany). Microperimetry was performed 12 months after surgery to evaluate retinal sensitivity in the central macula within 10-degree eccentricity.

Surgery

Using the Constellation Vision System (Alcon Japan Ltd, Tokyo, Japan), all 25-gauge vitrectomies were performed under local anesthesia by the same experienced surgeon (TS). IOP control was set at 20 mm Hg to maintain a stable intraoperative IOP. Phacoemulsification and intraocular lens implantation were also performed for all phakic patients aged 50 years or older.13,14

After core vitrectomy after the creation or confirmation of posterior vitreous detachment (PVD), ERM/ILM peeling was performed by direct grasping with a 25-gauge Grieshaber disposable forceps with the help of 0.025% Brilliant Blue G dye.15 The peeling was initiated at the supratemporal raphe to minimize mechanical damage to the papillomacular bundle, and the area of ILM peeling ranged from 2 to 4 disc diameters depending on the condition of each eye.

The sclerotomy sites were cauterized at the end of surgery to prevent leakage.

Optical Coherence Tomography Examinations

Spectral-domain OCT examinations were performed using a Cirrus OCT (Carl Zeiss Meditec AG). Only scans with a signal strength of ≥7 were analyzed. Preoperatively, all ERM cases were classified into 4 groups according to the ectopic inner foveal layer classification scheme proposed by Govetto et al.16 The presence or absence of a dissociated optic nerve fiber layer (DONFL) was ascertained at 12 months postoperatively.

The pRNFL thicknesses in the 4 quadrants (superior, temporal, inferior, and nasal), average cup-to-disc ratio, and cup volume were measured in the 200 × 200 optic disc cube scan mode. The 4 quadrants used for pRNFL measurements are shown in Figure 1A and C. The temporal quadrant was further divided into the upper, middle, and lower segments of 30 degrees each (Fig. 1A, D). The follow-up mode was used to evaluate the same peripapillary region from the second measurement onward.

F1
Figure 1:
A, Fundus photograph showing an epiretinal membrane in a right eye. B, Microperimetry at 12 months postoperatively using the MP1 with 37 stimulation loci covering the central retina within 10-degree eccentricity. C, The thickness of the peripapillary retinal nerve fiber layer (pRNFL) is measured in the 4 quadrants. The 0-degree and 90-degree directions indicate the right and superior sides, respectively. In the right eye, the superior, temporal, inferior, and nasal quadrants indicate areas within 45–135, 135–225, 225–315, and 315–45 degrees, respectively. D, The pRNFL thickness is determined in 12 segments. The temporal quadrant is subdivided into the upper (135–165 degrees), middle (165–195 degrees), and lower (195–225 degrees) segments. The numbers in C and D represent the pRNFL thickness values (in μm) in the corresponding quadrants (C) and segments (D).

Central macular thickness (CMT) was measured in the 200 × 200 macular cube scan mode. CMT was defined as the distance between the inner retinal surface and the inner border of the retinal pigment epithelium in the central 1-mm circle.

Microperimetry

Retinal sensitivity was evaluated with a microperimeter (MP1 software version 1.7.9; Nidek Co, Ltd) at 12 months postoperatively. All tests were performed by the same experienced examiner (RYM) in a darkened room with well-dilated pupils. After a 30-s fixation test, microperimetry was performed using white test stimuli of 0–20 decibels (dB), which is equivalent to a Goldmann III spot size with a 200-ms duration. Customized 37-loci stimuli covering the central macula within 10-degree eccentricity were projected on a white background at 1.27 cd/m2 (Fig. 1B).

Statistical Analyses

The data are presented as mean ± standard deviation. The BCVA measured using a Landolt C visual acuity chart was converted to logarithm of the minimum angle of resolution (logMAR) units for statistical analyses.

Significant differences between the eyes with ERM and their fellow eyes were determined using the t test if the data were normally and equally distributed; the Mann-Whitney rank-sum test was used if they were not. The significance of the differences in ratios between the eyes with ERM and the fellow eyes was determined using the chi-square test. The Friedman repeated-measures analysis of variance on ranks was performed to compare the clinical conditions within the same patient at different time points. This was followed by Dunn method or the Holm-Sidak method to detect significant differences between the preoperative and postoperative data. The correlation between pRNFL thickness and central retinal sensitivity was analyzed using the Pearson product-moment correlation.

A regression tree analysis, which is a type of multivariate analysis and allows participants to be subgrouped based on specific values of explanatory variables,17 was performed to predict pRNFL thickness in the temporal quadrant at 12 months postoperatively; the eyes with ERM were subgrouped based on the postoperative pRNFL thickness in the temporal quadrant as the objective variable and the preoperative (age, sex, history of hypertension, history of diabetes mellitus, history of glaucoma, BCVA, axial length, ERM classification proposed by Govetto et al,16 CMT, and pRNFL thickness in the temporal quadrant), intraoperative (combined vitrectomy with cataract surgery, creation of PVD, and area of ILM peeling), and postoperative (presence or absence of DONFL) parameters as the explanatory variables. Kruskal-Wallis 1 way analysis of variance on ranks was used to compare the postoperative pRNFL thicknesses of the groups of patients subdivided by regression tree analysis, followed by Dunn's method to detect significant differences between all pairs.

All statistical analyses were performed using JMP Pro 15 (SAS Institute Inc, Cary, NC, US) or SigmaPlot 14.5 (Systat Software, Inc, San Jose, CA, US). A P value of <0.05 was considered statistically significant.

RESULTS

Ninety-four consecutive patients scheduled for unilateral idiopathic ERM surgery were screened. Twelve patients met the exclusion criteria. Ultimately, the data for 82 eyes of 82 Japanese (East Asian) patients were analyzed (Table 1). Five patients with diabetes mellitus did not have any apparent diabetes-related complications, specifically no diabetic retinopathy. Preoperatively, there were significant differences in the BCVA and CMT between eyes with ERM and fellow eyes (both P < 0.001).

Table 1 - Preoperative Patient and Ocular Characteristics
ERM Eyes (n = 82) Fellow Eyes (n = 82) P Value
Age (y)
 Average ± SD 67.9 ± 8.1
 Range 46–82
Sex (female: male) 44: 38
Hypertension (yes: no) 35: 47
Diabetes (yes: no) 5: 77
Right: left 37: 45 45: 37
Glaucoma (yes: no) 7: 75 11: 71 0.454
Best-corrected visual acuity
 Average ± SD (logMAR) 0.22 ± 0.15 0.10 ± 0.12 <0.001
 Range (Snellen) 20/100–20/16 20/50–20/16
Intraocular pressure (mm Hg)
 Average ± SD 13.3 ± 2.7 13.2 ± 2.6 0.771
 Range 9-20 8-21
Central corneal thickness (μm)
 Average ± SD 529.1 ± 31.3 529.9 ± 33.2 0.879
 Range 450-612 462-621
Axial length (mm)
 Average ± SD 24.55 ± 1.58 24.52 ± 1.55 0.910
 Range 22.08–28.06 22.00–27.99
Lens status (phakia: IOL) 78: 4 75: 7 0.532
ERM stage (1: 2: 3: 4) 35: 30: 12: 5 not applicable
Central macular thickness (μm)
 Average ± SD 378.6 ± 80.4 260.0 ± 24.2 <0.001
 Range 210-663 198-343
ERM indicates epiretinal membrane; logMAR, logarithm of the minimum angle of resolution; IOL, intraocular lens; SD, standard deviation.
ERM staging scheme according to ectopic inner foveal layer, proposed by Govetto et al.16

Cataract surgery was performed in 77 of 78 (98.7%) phakic eyes with ERM and in 70 of 75 (93.3%) phakic fellow eyes, which was not significantly different. PVD was created during surgery in 14 (17.1%) eyes with ERM. DONFL was detected in 16 (19.5%) eyes 12 months after ERM surgery.

Visual Acuity, Intraocular Pressure, and Central Macular Thickness

The BCVAs were significantly improved at all postoperative time points in both eyes with ERM and the fellow eyes (all P < 0.001).

In the eyes with ERM, the postoperative IOPs after 1, 3, and 6 months were significantly lower than the preoperative value (all P < 0.001); in the fellow eyes, the postoperative IOPs at all time points were significantly lower than the preoperative value (all P < 0.001).

In the eyes with ERM, the CMTs were significantly higher and lower at 1 month and 12 months postoperatively, respectively, than the preoperative value (both P < 0.001). In the fellow eyes, the CMT was significantly increased at all postoperative time points (all P < 0.001).

Peripapillary Retinal Nerve Fiber Layer Thickness, Average Cup-to-Disc Ratio, and Cup Volume

In the eyes with ERM, the postoperative pRNFL thicknesses in the superior, inferior, and nasal quadrants were significantly higher than the corresponding preoperative values (all P < 0.001), except in the inferior quadrant at 12 months postoperatively. In contrast, the pRNFL thicknesses in the temporal quadrant at 3, 6, and 12 months postoperatively were significantly lower than the preoperative value (all P < 0.001; Fig. 2A–D, Table 2). Moreover, when the temporal quadrant was subdivided, a significant decrease in pRNFL thickness was detected in all 3 segments at 3, 6, and 12 months postoperatively (all P < 0.001) and in the middle segment at 1 month postoperatively (P = 0.041; Fig. 3).

F2
Figure 2:
Longitudinal changes in the thickness of the peripapillary retinal nerve fiber layer (pRNFL) in the superior (A), temporal (B), inferior (C), and nasal (D) quadrants; average cup-to-disc ratio (E); and cup volume (F). The abscissas represent the perioperative time points, and the ordinates represent the pRNFL thickness (A-D), the average cup-to-disc ratio (E), and cup volume (F). The t test or Mann-Whitney rank-sum test is performed to detect significant differences between the eyes with epiretinal membrane (ERM) and their fellow eyes. ns indicates not significant.
Table 2 - Longitudinal Changes in RNFL Thicknesses (μm) Divided into 4 Quadrants
Superior Temporal Inferior Nasal
ERM Eye Fellow Eye P value ERM Eye Fellow Eye P value ERM Eye Fellow Eye P value ERM Eye Fellow Eye P value
Pre 103.4 ± 21.0 106.8 ± 20.4 0.389 94.5 ± 22.8 75.7 ± 14.2 <0.001 106.5 ± 18.7 110.3 ± 18.7 0.200 66.8 ± 8.6 67.5 ± 10.3 0.988
1M 111.3 ± 21.7 109.0 ± 20.6 0.480 85.7 ± 15.8 78.2 ± 15.0 0.002 115.0 ± 17.4 112.0 ± 18.4 0.280 72.6 ± 9.1 69.9 ± 10.3 0.033
3M 110.4 ± 22.1 108.1 ± 20.5 0.494 79.2 ± 13.8 78.6 ± 15.3 0.793 112.0 ± 17.0 111.7 ± 18.1 0.901 72.8 ± 9.2 69.9 ± 10.8 0.013
6M 108.9 ± 22.3 108.4 ± 20.9 0.885 76.7 ± 13.4 78.5 ± 15.7 0.423 111.3 ± 17.2 110.1 ± 19.1 0.684 71.6 ± 8.8 70.0 ± 10.5 0.098
12M 107.8 ± 22.8 107.4 ± 21.0 0.898 73.9 ± 12.9 78.3 ± 15.5 0.049 109.0 ± 18.3 108.6 ± 22.0 0.638 70.4 ± 9.6 69.0 ± 10.7 0.145
ERM indicates epiretinal membrane; RNFL, retinal nerve fiber layer.The statistical analysis was performed using the t test or Mann-Whitney rank-sum test to detect significant differences between the eyes with ERM and the fellow eyes.

F3
Figure 3:
Longitudinal changes in the thickness of the peripapillary retinal nerve fiber layer (pRNFL) in the temporal quadrant (average) and temporal upper, temporal middle, and temporal lower segments in the eyes with epiretinal membrane. The abscissa and ordinate represent the perioperative time points and the pRNFL thickness, respectively.

In the fellow eyes, the pRNFL thicknesses in the superior and inferior quadrants did not significantly change postoperatively, whereas those in the temporal quadrant at all postoperative time points and in the nasal quadrant at 1, 3, and 6 months postoperatively were significantly higher (all P < 0.001; Fig. 2A–D, Table 2).

The pRNFL showed continuous thinning only in the temporal quadrant after ERM surgery, reaching a significant difference compared to fellow eyes at 12 months postoperatively (P = 0.049; Fig. 2B, Table 2).

In the eyes with ERM, the average cup-to-disc ratios and cup volumes at 1 and 3 months postoperatively were significantly smaller than the preoperative values (all P < 0.001), which was also true for the fellow eyes at 1, 3, and 6 months postoperatively (all P < 0.001; Fig. 2E, F).

Association Between Retinal Nerve Fiber Layer Thickness and Central Retinal Sensitivity

At 12 months postoperatively, the average central retinal sensitivity within 10-degree eccentricity was 18.63 ± 1.54 dB in the eyes with ERM and 18.68 ± 1.28 dB in the fellow eyes, without a significant difference.

In the eyes with ERM, central retinal sensitivity at 12 months postoperatively was significantly correlated with temporal pRNFL thickness at any time point (r = 0.240, P = 0.030 preoperatively; r = 0.293, P = 0.007 at 1 month; r = 0.332, P = 0.002 at 3 months; r = 0.348, P < 0.001 at 6 months; and r = 0.372, P < 0.001 at 12 months postoperatively; Fig. 4), whereas no significant correlation was found between these variables in the fellow eyes.

F4
Figure 4:
Correlation between the thickness of the peripapillary retinal nerve fiber layer (pRNFL) in the temporal quadrant at 12 months postoperatively and central retinal sensitivity within 10-degree eccentricity. The correlation between the 2 parameters is analyzed using the Pearson product-moment correlation.

Predictors of Postoperative Thickness in the Temporal Retinal Nerve Fiber Layer

Given that central retinal sensitivity showed the highest correlation with pRNFL thickness in the temporal quadrant at 12 months postoperatively, a regression tree analysis was performed to predict temporal pRNFL thickness at 12 months (Fig. 5). Patients with ERM were divided into 2 groups based on whether the preoperative pRNFL thickness in the temporal quadrant was <76 μm (Group 1) or ≥76 μm. The latter group was further subdivided into those aged <57 years (Group 4) and ≥57 years. The latter subpopulation was further subdivided into Groups 2 and 3 based on the preoperative temporal pRNFL thickness (<97 μm vs ≥97 μm, respectively). The average temporal pRNFL thicknesses for Groups 1 to 4 at 12 months postoperatively were 59.2 ± 9.4 μm, 71.8 ± 9.6 μm, 79.3 ± 9.1 μm, and 89.8 ± 14.6 μm, respectively. The postoperative temporal pRNFL thicknesses were significantly different across nearly all the pairs of groups (P < 0.001 for Groups 1 and 3, 1 and 4, and 2 and 3, P = 0.009 for Groups 1 and 2, and P = 0.003 for Groups 2 and 4), except between Groups 3 and 4.

F5
Figure 5:
Patients with epiretinal membrane (ERM) stratified by peripapillary retinal nerve fiber layer (pRNFL) thickness in the temporal quadrant at 12 months postoperatively using regression tree analysis. Patients indicated by rectangular-shaped boxes are stratified by each parameter, ie, preoperative temporal pRNFL thickness or patient age. Each cutoff value was determined automatically by the regression tree analysis programed in JMP Pro 15. Patients with ERM (n = 82) are subdivided into Groups 1–4. For each group, the average temporal pRNFL thickness at 12 months postoperatively is shown along with the number of patients.

DISCUSSION

This study's main findings were that the pRNFL in the temporal quadrant showed continuous thinning after ERM vitrectomy with ILM peeling, reaching statistical significance at 3, 6, and 12 months postoperatively, whereas that in fellow eyes increased significantly at all postoperative time points. The temporal pRNFL thickness was significantly correlated with central retinal sensitivity at 12 months after ERM surgery. The preoperative pRNFL thickness in the temporal quadrant and patient age were the main determinants of temporal pRNFL thickness at 12 months postoperatively.

In the fellow eyes, the pRNFL thicknesses in all 4 quadrants tended to increase especially in the early postoperative period, and those in the temporal quadrant at all postoperative time points and in the nasal quadrant at 1, 3, and 6 months postoperatively were significantly increased. A subgroup analysis demonstrated that pRNFL thicknesses were almost unchanged in the fellow eyes without cataract surgery (n = 12; data not shown). Based on these findings, we speculate that one of the mechanisms of pRNFL changes in the fellow eyes is surgery-induced inflammation. Another is a preoperative underestimation of the pRNFL thickness because of a cataract-induced decrease in transparency, as suggested by Cheng et al.18 Similarly, the CMT in the fellow eyes increased significantly postoperatively, which is consistent with the findings of previous investigations of the relationship between cataract and macular thickness.19,20

In the eyes with ERM—nearly all phakic eyes underwent combined vitrectomy with cataract surgery—the postoperative pRNFL thicknesses in the superior, inferior, and nasal quadrants were significantly increased, except for the values in the inferior quadrant at 12 months postoperatively. In contrast, those in the temporal quadrant decreased continuously postoperatively. The mechanism of this thinning has not been fully elucidated, but several surgical manipulations have been suggested as its cause, eg, retinal toxicity by the vital dye, phototoxicity from endoillumination, IOP fluctuation, and mechanical damage induced by PVD creation.10 If phototoxicity or PVD creation was the main cause of pRNFL thinning, the pRNFL in all quadrants, instead of only the temporal quadrant, would be affected. However, most postoperative pRNFL thicknesses in the superior, inferior, and nasal quadrants were significantly increased after ERM surgery. The current study also used Brilliant Blue G dye as an adjuvant for ILM peeling, which has not been reported to be toxic to the retina. IOP was strictly controlled during surgery. Therefore, the continuous pRNFL thinning in the temporal quadrant after ERM surgery observed in this study may not be attributed to these factors.

Scupola et al12 demonstrated a significant correlation between the area of arcuate nerve fiber layer swelling, which corresponded to the areas of surgical grasping of the ILM, and the reduction in pRNFL thickness. They suggested that mechanical damage to retinal nerve fibers by surgical grasping is a cause of pRNFL thinning after ERM surgery with ILM peeling. In contrast, ILM peeling was initiated at the supratemporal raphe in all cases in the current study; however, all 3 segments of the temporal quadrant showed a similar tendency toward a decrease in pRNFL thickness, suggesting that mechanical grasping during surgery is not the main cause of continuous pRNFL thinning.

Sakimoto et al21 demonstrated that, among patients with primary open-angle glaucoma, the pRNFL thicknesses in the superior and inferior quadrants were significantly lower, and disc parameters, including the cup-to-disc ratio and cupping area, had significantly higher values in the eyes with ERM than in those without ERM. They suggested that the concomitant ERM led to glaucoma progression. In the current study, the pRNFL thicknesses in the superior and inferior quadrants, the average cup-to-disc ratio, and cup volume of the eyes with ERM and their fellow eyes were not different at any time point. Moreover, the IOPs were significantly lower at 1, 3, and 6 months postoperatively than preoperatively, which was probably due to cataract extraction. Previous studies have demonstrated a continuous IOP reduction after cataract surgery,22,23 and the combined vitrectomy with cataract surgery was performed in most eyes with ERM in the current study. Therefore, this study's results suggest that the mechanism of continuous pRNFL thinning is different from that in glaucomatous eyes.

Lim et al24 demonstrated that the transient increases in pRNFL thickness, probably due to surgery-induced inflammation, returned to preoperative levels by 6 months after surgery in eyes with intraocular lens dislocation undergoing vitrectomy without macular manipulation. In the current study, the pRNFL thickness in the temporal quadrant showed continuous thinning, whereas most of the postoperative pRNFL thicknesses in the other quadrants significantly increased. Notably, the main difference in surgical manipulation between the study by Lim et al and the current study was the addition of ERM/ILM peeling. Therefore, ERM/ILM removal may be the main cause of continuous pRNFL thinning in the temporal quadrant.

In the current study, central retinal sensitivity was best correlated with pRNFL thickness in the temporal quadrant at 12 months postoperatively. Regression tree analysis showed that the postoperative temporal pRNFL thickness was lower in patients with a preoperative temporal pRNFL thickness of <76 μm than in those with a thickness of ≥76 μm. In the patients with a preoperative temporal pRNFL thickness of ≥76 μm, the postoperative temporal pRNFL thickness was lower in those aged ≥57 years than in those aged <57 years (P value not shown). These findings suggest that it is important to consider the potential risk of deterioration in central retinal sensitivity after ERM vitrectomy with ILM peeling in patients with thinner temporal pRNFL preoperatively and in older adults.

This study has some limitations. First, the postoperative follow-up period was 12 months. Therefore, longer-term observations are needed to ascertain the progression of pRNFL thinning in the temporal quadrant. Second, vitrectomy was performed with ILM peeling for all ERM cases to completely remove the ERM and prevent a recurrence. Thus, comparative studies are warranted to evaluate pRNFL thickness and retinal sensitivity after ERM vitrectomy with and without ILM peeling. Third, microperimetry was only performed at 12 months postoperatively because of its potential to interfere with routine clinical examinations if performed at each visit; therefore, it was not approved by the Institutional Review Board. Finally, artifacts on the OCT images may have led to the overestimation of pRNFL thickness in eyes with ERM.25,26

In conclusion, longitudinal changes in pRNFL thicknesses were investigated after ERM vitrectomy with ILM peeling. The pRNFL in the temporal quadrant showed continuous postoperative thinning, possibly because of the removal of the ERM/ILM. pRNFL thickness in the temporal quadrant was significantly correlated with central retinal sensitivity at 12 months postoperatively. The main determinants of postoperative pRNFL thickness in the temporal quadrant were the preoperative pRNFL thickness in the same quadrant and patient age. These findings highlight the importance of discussing the potential risk of deterioration in central retinal sensitivity after ERM vitrectomy with ILM peeling in patients who have a thin temporal pRNFL and older adults.

ACKNOWLEDGMENTS

The authors thank Koji Yonemoto, PhD, for statistical assistance and Editage (www.editage.com) for English language editing.

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Keywords:

epiretinal membrane; internal limiting membrane; retinal nerve fiber layer; retinal sensitivity; vitrectomy

Copyright © 2022 Asia-Pacific Academy of Ophthalmology. Published by Wolters Kluwer Health, Inc. on behalf of the Asia-Pacific Academy of Ophthalmology.