Clinical significance of ectopic inner foveal layers in patients with idiopathic epiretinal membranes

Subtyping stage 3 epiretinal membrane: a comprehensive study of ectopic inner foveal layers architecture and its clinical implications

AIMS

To evaluate the visual function and foveal architecture in patients with stage 3 idiopathic epiretinal membrane (iERM).

METHODS

A cross-sectional observational study included 56 eyes of 52 patients with stage 3 iERM. The patients were classified into type A ectopic inner foveal layers (EIFL) and type B EIFL based on the presence of a continuous hyporeflective band. Visual function and foveal microarchitecture were assessed in enrolled eyes. Best-corrected visual acuity (BCVA), metamorphopsia scores, retinal sensitivity and optical coherence tomography (OCT)/OCT angiography features were compared between two subtypes.

RESULT

The BCVA in type A EIFL and type B EIFL was 0.22 logarithm of minimal angle of resolution (logMAR) (0.15 logMAR, 0.40 logMAR) and 0.53±0.23 logMAR, respectively (p=0.002). Type B EIFL had higher average metamorphopsia scores, especially horizontal metamorphopsia scores, than type A (p=0.013, p=0.007, respectively). Type B EIFL had worse central 2° foveal sensitivity than type A (p=0.034). Type B EIFL had thicker central foveal thickness and EIFL thickness (514.08±73.80 µm vs 444.41±56.57 µm, p=0.001; 159.75±78.30 µm vs 48.44±18.37 µm, p<0.0001; respectively). The foveal avascular zone area of type B EIFL was smaller than that of type A (0.042±0.022 mm2 vs 0.077±0.039 mm2, p<0.0001). The vessel density and flow area of the superficial vascular complex in type B EIFL were larger than those in type A (both p=0.001).

CONCLUSIONS

Type B EIFL demonstrated significantly worse visual function than type A EIFL, along with marked differences in foveal microstructure and microvasculature. Our study complements the current staging of iERM and helps determine the optimal timing of iERM surgery.

Prevalence and significance of fovea plana in patients with epiretinal membrane

INTRODUCTION

Fovea plana is indicative of an immature inner retina, yet its association with epimacular membrane (ERM) remains unexplored. This study aims to investigate the prevalence of fovea plana in the contralateral eye of patients diagnosed with ERM.

METHODS

A retrospective analysis was conducted on consecutive patients in a monocentric tertiary ophthalmic department between January and April 2021. The study included all patients referred for ERM, with dense optical coherence tomography (OCT) B-scans utilized to assess the incidence of fovea plana in the contralateral eye. Patients with bilateral ERM were excluded from the analysis.

RESULTS

Out of 181 patients, 26 exhibited fovea plana in the contralateral eye, resulting in an incidence rate of 14.3%. Demographic characteristics, OCT patterns, and indications for surgery did not differ significantly between patients with and without fovea plana.

DISCUSSION

The prevalence of fovea plana in patients with ERM did not exhibit a statistically significant increase compared to the reported incidence in patients undergoing preoperative cataract surgery.

CONCLUSION

In our cohort, the incidence of fovea plana in patients with ERM was determined to be 14.3%.

Elevated hyperreflective foci as a novel characteristic in idiopathic epiretinal membrane by optical coherence tomography angiography

PURPOSE

The objective of this study was to analyze hyperreflective foci at the vitreous-retinal interface in cases of idiopathic epiretinal membrane (iERM) using enface-OCT.

METHODS

This study included 47 patients (52 eyes) diagnosed with iERM between January 2020 and July 2023. We observed changes in hyperreflective foci in the macular area at each stage of iERM using OCTA on a 6 mm slab of the VRI. Evaluations included the density and percentage of hyperreflective foci of the epiretinal membrane at each stage, as well as the relationship between hyperreflective foci density and other OCT parameters, such as macular thickness and changes in macular superficial vascular density.

RESULTS

Statistically significant differences in hyperreflective foci density and percentage were observed across the four stages of patients (p < 0.05). Additionally, statistically significant differences in superficial vascular density were noted among the four stages (p < 0.05). Hyperreflective foci area percentage and density correlated significantly with hyperreflective foci, FAZ area, and FAZ perimeter (p < 0.005). However, no correlation was found between hyperreflective foci density and area percentage with superficial vascular density and superficial perfusion density (p > 0.05).

CONCLUSION

Hyperreflective foci were identified in all stages of iERM, with their number and density increasing as the disease progressed.

SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY INSIGHTS INTO IDIOPATHIC EPIRETINAL MEMBRANE SURGERY OUTCOMES

PURPOSE

The aim of this study is to assess the prognostic value of a classification system that includes the presence of ectopic inner foveal layers and other anatomical variables identified in spectral-domain optical coherence tomography for idiopathic epiretinal membrane (ERM) surgery.

METHODS

A descriptive-analytic, longitudinal, retrospective study was conducted on patients with idiopathic ERMs treated with pars plana vitrectomy from January 2017 to December 2021. Clinical data and spectral-domain optical coherence tomography images were reviewed presurgery and 12 months postsurgery. The primary outcome measured was best-corrected visual acuity (BCVA) before and after surgery, analyzing the impact of anatomical factors on BCVA in patients undergoing ERM surgery.

RESULTS

This study included 342 eyes from 323 patients. Postsurgical evaluations showed significant reductions in central foveal thickness across all ERM stages, with most Stage 4 ERMs regressing to Stage 3. The mean improvement in BCVA was significant for all stages, with earlier stages showing better results. The presence of macular edema and ellipsoid zone disruption were significant predictors of postsurgical BCVA, while disorganization of the retinal inner layer showed an association with visual recovery but was not conclusively predictive.

CONCLUSION

This study highlights the importance of spectral-domain optical coherence tomography in assessing retinal changes in idiopathic ERMs, demonstrating the prognostic value of ectopic inner foveal layers stage scheme and other anatomical variables such as ellipsoid zone disruption and macular edema presence on BCVA. These findings offer insights into surgical prognostication and the potential for personalized treatment strategies.

Title - Long term outcomes of vitrectomy and ERM peel: Can pre-operative metamorphopsia measured using the D-Chart help improve surgical candidate selection?

PURPOSE

To assess the predictive value of pre-operative metamorphopsia, measured using the D-Chart, in patients undergoing epiretinal membrane (ERM) surgery and how this relates to improvement in quality of life after surgery.

METHODS

17 patients from vitreo-retinal surgery clinics at a tertiary ophthalmology centre were recruited when listed for pars plana vitrectomy (PPV) with ERM peel between September 2019 - February 2020. Pre-operatively patients underwent visual acuity (VA), Visual-Function Index 14 (VF-14) and metamorphopsia (D-Chart-Thomson Software Solutions) assessment and answered a questionnaire regarding cardinal ERM symptoms. Post-operatively patients were re-assessed in the same domains.

RESULTS

13 patients completed the protocol (inclusion rate 76%) with a mean follow-up of 32.1 (± 3.1) months. Mean pre-operative VA of the affected eye was 0.42 logMAR (± 0.25). Mean pre-operative VF-14 score was 81.51 (± 12.8) and mean M-Score of the affected eye was 14.6 (± 12.7). Post-operatively, mean VA of the operated eye was 0.11 logMAR (± 0.11), mean VF-14 score was 97.4 (± 3.8) and mean M-Score was 1.31 (± 2.8). Mean improvement in VA was 0.31 logMAR (p < 0.001), in VF-14 15.9 (p = 0.002), and M-Score -13.3 (p = 0.003). There was a significant association between pre-operative D-Chart score and improvement in VA (r = -0.570, p = 0.042), visual functioning (r = 0.606 p = 0.028) and metamorphopsia (r = 0.916 p < 0.001), with those demonstrating poorer D-Chart scores showing greater improvements.

CONCLUSION

Pre- and post-operative visual distortion measured using the D-Chart, correlates with vision related quality of life in patients undergoing epiretinal membrane surgery. Patients with worse pre-operative distortion scores noticed the greatest improvements in distortion and vision related quality of life following surgery. With a mean follow-up time of 32.1 months, this long-term follow-up data further reinforces the efficacy of vitrectomy and ERM peel by demonstrating significant and sustained improvement in visual acuity, metamorphopsia and visual functioning. The authors suggest there is a role for D-Chart assessment pre-operatively to improve selection of patients in ERM surgery.

Retinal vascular arcade angle as a biomarker for visual improvement after epiretinal membrane surgery

OBJECTIVES

To investigate the changes in the temporal vascular angles after epiretinal membrane (ERM) surgery and utilize the angles to predict visual outcomes.

METHODS

A total of 168 eyes from 84 patients with unilateral ERM who underwent vitrectomy were enrolled from a single institution. The angles of temporal venous (anglevein) and arterial arcades (angleartery) were measured on fundus photographs. The relationships between the angles and the best-corrected visual acuity (BCVA) were explored and multivariable logistic models and receiver operating characteristic (ROC) curves were analyzed to identify the factors that predicted visual outcomes.

RESULTS

At baseline, both angleartery and anglevein were narrower in the eyes with ERM than the fellow eyes (p < 0.001 and 0.007) but had no correlation with the baseline BCVA (p = 0.754 and 0.804). Postoperatively, the angleartery and anglevein significantly widened (both p < 0.001) and a greater BCVA improvement was associated with a greater widening of the angleartery (p = 0.029) and anglevein (p = 0.050). Multivariable logistic analyses found a narrower baseline angleartery compared to the fellow eye had a higher chance for BCVA improvement ≧ 2 lines (Odds ratio = 0.97; 95% CI, 0.94-0.99; p = 0.016). ROC curve showed the baseline difference in the angleartery between bilateral eyes predicted BCVA improvement ≧ 2 lines (area under the curve = 0.74; p = 0.035), and a 0.73 sensitivity and 0.80 specificity with a cut-off value of -27.19 degrees.

CONCLUSIONS

The retinal vascular angles widened after ERM surgery and the fundus photograph-derived angles may serve as a highly-accessible biomarker to predict postoperative visual outcomes.

Clinical evaluation of deep learning systems for assisting in the diagnosis of the epiretinal membrane grade in general ophthalmologists

BACKGROUND

Epiretinal membrane (ERM) is a common age-related retinal disease detected by optical coherence tomography (OCT), with a prevalence of 34.1% among people over 60 years old. This study aims to develop artificial intelligence (AI) systems to assist in the diagnosis of ERM grade using OCT images and to clinically evaluate the potential benefits and risks of our AI systems with a comparative experiment.

METHODS

A segmentation deep learning (DL) model that segments retinal features associated with ERM severity and a classification DL model that grades the severity of ERM were developed based on an OCT dataset obtained from three hospitals. A comparative experiment was conducted to compare the performance of four general ophthalmologists with and without assistance from the AI in diagnosing ERM severity.

RESULTS

The segmentation network had a pixel accuracy (PA) of 0.980 and a mean intersection over union (MIoU) of 0.873, while the six-classification network had a total accuracy of 81.3%. The diagnostic accuracy scores of the four ophthalmologists increased with AI assistance from 81.7%, 80.7%, 78.0%, and 80.7% to 87.7%, 86.7%, 89.0%, and 91.3%, respectively, while the corresponding time expenditures were reduced. The specific results of the study as well as the misinterpretations of the AI systems were analysed.

CONCLUSION

Through our comparative experiment, the AI systems proved to be valuable references for medical diagnosis and demonstrated the potential to accelerate clinical workflows. Systematic efforts are needed to ensure the safe and rapid integration of AI systems into ophthalmic practice.

Intraoperative slow-release dexamethasone intravitreal implant (Ozurdex) in epiretinal membrane peeling surgery: a prospective randomized controlled trial

Purpose: This study aimed to determine the efficacy of the dexamethasone (DEX) intravitreal implant for the regression of macular edema and the improvement of best-corrected visual acuity (BCVA) after the removal of idiopathic epiretinal membrane (ERM). Methods: This prospective randomized controlled trial recruited 81 patients with idiopathic ERM. These patients all underwent 25-gauge pars plana vitrectomy combined with ERM and internal limiting membrane peeling surgery. Among them, 41 eyes in the DEX group received additional DEX implants and 40 in the non-DEX group did not. Outcomes including central retinal thickness (CRT), BCVA, and intraocular pressure were measured 1 and 3 months after surgery. Results: The DEX group had thinner CRTs compared to the non-DEX group at 1 month postoperatively (p <0.05), but did not differ significantly at the 1-week and 3-month follow-up visits (p = 0.109 and p = 0.417, respectively). There were no statistical differences with respect to BCVA (p = 0.499, 0.309, 0.246, and 0.517, respectively) and intraocular pressure (p = 0.556, 0.639, 0.741, and 0.517, respectively) between the two groups at each point of follow-up visits. Conclusion: DEX accelerated the reduction of CRT at 1 month after surgery. However, no evidence of further anatomical (CRT) or functional (BCVA) benefits using DEX was observed at 3 months. Clinical Trial Registration: https://clinicaltrials.gov/, identifier NCT05416827.

Correlation between Severity of Idiopathic Epiretinal Membrane and Irvine-Gass Syndrome

A higher risk of pseudophakic cystoid macular edema (PCME) has been reported in patients with preoperative idiopathic epiretinal membrane (ERM); however, whether the formation of PCME depends on the grade of ERM has not been well established. We conducted a retrospective case-control study of 87 eyes of 78 patients who were preoperatively diagnosed with idiopathic ERM and had undergone cataract surgery. Patients were divided into two groups: PCME and non-PCME groups. After cataract surgery, the ERM status was graded using the Gass and Govetto classifications. Both the central macular thickness (CMT) and ERM grade increased after surgery, and higher preoperative CMT and ERM grades were found in the PCME group. The association between higher-grade ERM and the development of PCME was significant in the Govetto classification (grade 2, odds ratio (OR): 3.13; grade 3, OR: 3.93; and grade 4, OR: 16.07). The study results indicate that close attention should be given to patients with ERM with the presence of an ectopic inner foveal layer before cataract surgery.

Multimodal Assessment of the Prognostic Role of Ectopic Inner Foveal Layers on Epiretinal Membrane Surgery

BACKGROUND

To perform a multimodal assessment of the ectopic inner foveal layers' (EIFL) prognostic role on idiopathic epiretinal membrane (ERM) surgery.

METHODS

We retrospectively followed-up for 12 months 27 patients who underwent ERM surgery and stratified them based on EIFL presence (group 1) or absence (group 2) at baseline. Central Retinal Thickness (CRT) and best-corrected visual acuity (BCVA) were compared pre- and post-operatively at 1, 4 and 12 months, whereas fixation stability (FS), macular sensitivity (MS) and multifocal electroretinogram (mfERG) responses were confronted at baseline and 12 months.

RESULTS

In group 1, BCVA improved at 4 and 12 months (MD = 0.14 (SE = 0.04); MD = 0.13 (SE = 0.05), respectively) as well as in group 2 (MD = 0.31 (SE = 0.07); MD = 0.41 (SE = 0.08), respectively). CRT did not change in group 1, whereas it decreased in group 2 at 4 and 12 months (MD = -73.13; SE = 23.56; MD = -76.20; SE = 23.56). MS showed no changes in both groups after surgery. FS did not change in group 1, whereas group 2 improved FS 2° (+8.91 ± 13.97) and FS 4° (+4.33 ± 3.84). MfERG P1 wave did not change in group 1, while in group 2 αP1-2, αP1-3 and αP1-4 improved postoperatively (27.97 ± 27.62; 12.51 ± 17.36; 10.49 ± 17.19, respectively).

CONCLUSIONS

Multimodal assessment confirmed that EIFL negatively affected ERM surgery outcomes.

The Classification of Stages of Epiretinal Membrane using Convolutional Neural Network on Optical Coherence Tomography Image

BACKGROUND AND OBJECTIVE

The gold standard for diagnosing epiretinal membranes is to observe the surface of the internal limiting membrane on optical coherence tomography images. The stages of the epiretinal membrane are used to decide the condition of the health of the membrane. The stages are not detected because some of them are similar. To accurately classify the stages, a deep-learning technology can be used to improve the classification accuracy.

METHODS

A combinatorial fusion with multiple convolutional neural networks (CNN) algorithms are proposed to enhance the accuracy of a single image classification model. The proposed method was trained using a dataset of 1947 optical coherence tomography images diagnosed with the epiretinal membrane at the Taichung Veterans General Hospital in Taiwan. The images consisted of 4 stages; stages 1, 2, 3, and 4.

RESULTS

The overall accuracy of the classification was 84%. The combination of five and six CNN models achieves the highest testing accuracy (85%) among other combinations, respectively. Any combination with a different number of CNN models outperforms any single CNN algorithm working alone. Meanwhile, the accuracy of the proposed method is better than ophthalmologists with years of clinical experience.

CONCLUSIONS

We have developed an efficient epiretinal membrane classification method by using combinatorial fusion with CNN models on optical coherence tomography images. The proposed method can be used for screening purposes to facilitate ophthalmologists making the correct diagnoses in general medical practice.

Long-term Follow-up Results of Idiopathic Epiretinal Membrane Removal in the Eyes with Ectopic Inner Foveal Retinal Layers

PURPOSE

The purpose of this study was to evaluate pre- and perioperative factors related to time for the evolution of ectopic inner foveal layers (EIFL) following pars plana vitrectomy (PPV) for epiretinal membrane (ERM) peeling.

METHODS

This retrospective study included 81 consecutive eyes with idiopathic ERM that underwent vitrectomy surgery. Standard PPV + internal limiting membrane peeling was performed in all cases. A comprehensive ophthalmic examination was performed for all patients before and 1, 3, 6, and 12 months, and the last follow-up after surgery. We observed the postoperative improvement in EIFL severity in the short-term and longest follow-up and evaluated anatomical and functional improvement. Several parameters were assessed using the multivariate COX proportional hazard analysis.

RESULTS

Eighty patients (81 eyes) with a mean age of 70.33 ± 7.75 years were followed for a mean of 34.37 ± 23.61 months, and 55.5% of eyes (45 eyes) with EIFL ERM showed improvement of foveal contour to a better stage at the last follow-up. The median estimated time for evolving to a better stage was 29.73 months for stage 2, 49.68 months for stage 3, and 38.67 months for stage 4 (P = 0.001, log-rank test). The severity of EIFL was the only significant factor for time to evolution of EIFL ERM to a better stage, where the eyes with stage 4 EIFL ERM showed faster foveal contour improvement compared to those with stage 3 EIFL ERM (hazard ratio: 0.317, 95% confidence interval = 0.164-0.615, P = 0.001).

CONCLUSION

On assessing preoperative factors, the preoperative EIFL stage emerged as the sole significant factor for EIFL ERM improvement to a better disease stage. This study reports some of the longest follow-up durations for patients undergoing PPV for EIFL ERM, and both functional and anatomical improvements were observed across all stages of EIFL, including in the advanced stage 4 EIFL ERM.

Image processing and quantification analysis for optical coherence tomography angiography in epiretinal membrane

BACKGROUND

To explore image processing methods for optical coherence tomography angiography (OCTA) of the epiretinal membrane (ERM), and to evaluate the impact of ERM on vision by analyzing the retinal vasculature.

METHODS

Thirty eyes of 30 patients with idiopathic ERM who underwent OCTA were retrospectively evaluated. Image processing of OCTA, including the Mexican hat filter (MHF) and exclusion of the foveal avascular zone (FAZ), was attempted using Fiji. OCTA parameters, including vessel density (VD), fractal dimension (FD), and vessel tortuosity (VT), were measured for large vessels only, capillaries only, and the whole vasculature. Pearson correlation analysis was used to evaluate the correlations between best-corrected visual acuity (BCVA) and OCTA parameters.

RESULTS

The correlations between BCVA and retinal vasculature were much increased when the capillaries only instead of the whole vasculature was used for analysis. Both higher VD and FD of capillaries were correlated with better BCVA, and MHF largely increased their correlations (P < 0.0001 for both). In contrast, both higher VD and FD of the large vessels were associated with poorer BCVA (P = 0.042 and 0.049, respectively). A higher VT of capillaries was correlated with better BCVA, and both MHF and exclusion of the FAZ were necessary to reveal their correlations (P = 0.028) CONCLUSIONS: Separation of large vessels and capillaries was necessary to reveal the correlation between retinal vasculature and BCVA in ERM. MHF was necessary to elucidate all microvascular parameters of capillaries, and exclusion of the FAZ was mandatory for evaluation of VT.

Retinal Vascular Tortuosity Index Change after Idiopathic Epiretinal Membrane Surgery: Does Internal Limiting Membrane Peeling Affect Retinal Vascular Tortuosity?

BACKGROUND

Idiopathic epiretinal membrane (iERM) surgery is one of the most commonly performed vitreoretinal surgeries, and the issue of internal limiting membrane (ILM) peeling in ERM surgery is still controversial. The aims of this study are to evaluate the changes in retinal vascular tortuosity index (RVTI) after pars plana vitrectomy for the iERM using optical coherence tomography angiography (OCTA) and to assess whether ILM peeling has an additional effect on RVTI reduction.

METHODS

This study included25 eyes of 25 iERM patients who underwent ERM surgery. The ERM was removed without ILM peeling in 10 eyes (40.0%), and the ILM was peeled in addition to the ERM in 15 eyes (60.0%). The existence of the ILM after ERM peeling was checked with second staining in all eyes. Best corrected visual acuity (BCVA) and 6 × 6 mm en-face OCTA images were recorded before surgery and at the first month postoperatively. A skeleton model of the retinal vascular structure was created following Otsu binarization of en-face OCTA images using ImageJ software (1.52U). RVTI was calculated as the ratio of each vessel length to its Euclidean distance on the skeleton model using the Analyze Skeleton plug-in.

RESULTS

The mean RVTI declined from 1.220 ± 0.017 to 1.201 ± 0.020 (p = 0.036) in eyes with ILM peeling and from 1.230 ± 0.038 to 1.195 ± 0.024 in eyes without ILM peeling (p = 0.037). There was no difference between the groups in terms of postoperative RVTI (p = 0.494). A statistically significant correlation was found between postoperative RVTI and postoperative BCVA (rho = 0.408, p = 0.043).

CONCLUSIONS

The RVTI is an indirect indicator of the traction created by the iERM on retinal microvascular structures, and it was effectively reduced after iERM surgery. The postoperative RVTIs were similar in cases who underwent iERM surgery with or without ILM peeling. Therefore, ILM peeling may not have an additive effect on the loosening of microvascular traction and thus may be reserved for recurrent ERM surgeries.

EPIRETINAL MEMBRANE WITH FOVEAL HERNIATION: Visual and Surgical Outcomes

PURPOSE

Foveal herniation occurs when neuroretinal tissue protrudes through and above the level of an epiretinal membrane. This study describes the visual symptoms and spectral domain optical coherence tomography findings associated with foveal herniation and evaluates the postoperative visual, anatomical, and surgical outcomes.

METHODS

A multicenter retrospective review of patients diagnosed with epiretinal membrane identified 59 patients with preoperative foveal herniation on spectral domain optical coherence tomography. Data regarding visual symptoms, preoperative and postoperative best-corrected visual acuity (BCVA), central retinal thickness, macular volume, and size of foveal herniation were collected, and statistical analysis was performed.

RESULTS

A total of 58 of the 59 patients with foveal herniation underwent surgical epiretinal membrane peeling, with foveal contour restored in 53.5% of patients after surgery. Average BCVA improved from 20/80 to 20/40 Snellen equivalent at most-recent postoperative visit (P < 0.0001). The average central retinal thickness decreased from 632 µm to 432 µm (P < 0.0001) and the average macular volume decreased from 11.3 mm3 to 9.5 mm3 (P < 0.0001) at 3 months postoperatively. Preoperatively, greater herniation height was associated with worse BCVA (P = 0.008), greater central retinal thickness (P = 0.01), retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone abnormality, and external limiting membrane abnormalities (P < 0.05). Postoperatively, there was a decrease in retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone, and external limiting membrane abnormality (P < 0.05) on spectral domain optical coherence tomography.

CONCLUSION

Patients with larger foveal herniation height had greater preoperative central retinal thickness, worse preoperative and postoperative BCVA, and more intraretinal abnormalities on spectral domain optical coherence tomography. Surgical epiretinal membrane peeling in patients with foveal herniation resulted in a significant improvement in patients' BCVA and microstructural abnormalities.

Choroidal morphologic and vascular features in patients with unilateral idiopathic epiretinal membranes: An optical coherence tomography analysis integrated with assessment of retinal layers

Introduction

Integrated analysis of retinal and choroidal morphologic and vascular features is urgently needed to examine whether and how these two elements interact with each other, thus contributing to visual impairment in patients with idiopathic epiretinal membranes (iERMs).

Methods

An observational retrospective study consisting of 181 patients diagnosed with unilateral iERM between August 2019 and July 2022 was carried out at Peking University Third Hospital. All patients underwent a standardized set of ophthalmologic examinations, including EDI-OCT and OCTA scanning, and were subsequently categorized into four stages according to current classification schemes based on their OCT findings. Altogether, 15 qualitative and quantitative parameters of both the retina (full-layer, inner and outer layers) and choroid were identified.

Results

The results revealed variations in the choroidal vascularity index (CVI) among different stages of iERMs (p < 0.001) for the first time. Distributions of retinal parameters across four stages of iERMs were validated. Correlation analysis between choroidal and retinal parameters showed that the CVI was associated with both inner and outer retinal morphologic biomarkers. Functional damage to retinal integrity was determined to be a strong contributor to visual acuity reduction in iERMs.

Discussion

This study complemented our present understanding of posterior segment structural and vascular alterations in iERMs.

Insights into the underlying choroid in different stages of idiopathic epiretinal membranes after Viteromacular surgery

PURPOSE

The purpose of the study was to longitudinally investigate the correlation between choroidal morphologic and vascular parameters and postoperative visual outcome in different stages of idiopathic epiretinal membranes (iERMs).

METHODS

A prospective, observational, institutional case series of 102 consecutive patients diagnosed with unilateral iERMs were recruited at Peking University Third Hospital and were followed up for 12 months after surgical treatment with vitrectomy. Participants were classified into four stages according to current staging scheme. All eligible subjects underwent standardized imaging evaluation of choroidal parameters including subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), and choroidal capillary perfusion (CCP) at baseline and each follow-up by enhanced depth optical coherence tomography (EDI-OCT) and OCT angiography (OCTA). Longitudinal follow-up of choroidal parameters over 12 months was analysed, and their correlations with best-corrected visual acuity (BCVA) were also assessed for predictive prognostic value.

RESULTS

CVI and CCP were significantly correlated with BCVA at each follow-up examination (all p < 0.05). However, SFCT exhibited no variation among different stages of iERMs at baseline (p = 0.981) or during follow-up (p = 0.520). The preoperative CVI correlated with 12-month postoperative BCVA (p < 0.001) and its predictive prognostic effect on BCVA was validated in multiple regression analysis (p = 0.006).

CONCLUSION

CVI varied among different stages of iERM and was significantly correlated with visual outcomes after the surgery. CVI could serve as a predictive prognostic marker in iERMs, which further indicates the underlying choroid should be taken into consideration in clinical evaluation of iERMs.

Influence of Preoperative Foveal Layers’ Thickness on Visual Function and Macular Morphology by Phacovitrectomy for Epiretinal Membrane

Background. The aim of this retrospective study with short, differently dispersed follow-up is to record the relationships between the pathologies of the individual foveal layers, measured by spectral domain optical coherence tomography (SD-OCT), and to investigate their influence on pre- and postoperative best-corrected decimal far visual acuity (BCVA) by phacovitrectomy for epiretinal membrane (ERM) in comorbidity with cataract. Patients and Methods. 208 eyes of 173 patients with symptomatic idiopathic ERM and moderate cataract were included. Results. In all OCT morphological stages of ERM, as well as in their combination with macular lamellar hole (MLH) and vitreomacular traction (VMT), a significant difference in the thickness of the individual fovea layers was found. In addition, the entire fovea thickening led to the proportional thickening of the individual fovea layers ( $p<0.001$ ). The larger the central foveolar (CFT, R2 = −0.238, $p=0.002$ ), maximum foveal (MFT, R2 = −0.267, $p=0.001$ ), and ONL thickness (R2 = −0.16, $p=0.044$ ) were preoperatively, the worse the initial visual acuity was at all OCT stages of ERM. This was even more significant in the presence of a tractive component in the case of MLH or VMT ( $p<0.001$ ). In ERM without a traction component, only ONL thickening led to significant postoperative visual acuity reduction (R2 = −0.163, $p=0.047$ ). The foveolar retinal thickening (CFT and MFT) of the pure ERM is directly associated with distortion of the retinal layers (R2 = 0.292, $p<0.001$ and R2 = 0.287, $p<0.001$ ) as well as with separation of the ERM (R2 = 0.168, $p=0.034$ and R2 = 0.187, $p=0.018$ ). When ERM was combined with tractive component, CFT, ONL, and INL thickness correlated (positively) with the integrity of ellipsoid zone (R2 = 0.342, $p<0.05$ ) and external limiting membrane (R2 = 0.548, $p<0.001$ ). Conclusions. ONL thickening in ERM without a tractive component serves as a limited prognostic factor of postoperative visual acuity decrease. The preoperative BCVA in the groups of ERM with traction component showed significant correlation with CFT as well as with the thickness of individual foveal layers. VMT in ERM correlates with the disintegration of the ellipsoid zone.

Preoperative ocular coherence tomographic prognosticators of visual acuity after idiopathic epiretinal membrane surgery

PURPOSE

To provide a current review of the evidence for the utility of preoperative ocular coherence tomography (OCT) parameters in prognosticating postoperative visual acuity and visual improvement after idiopathic epiretinal membrane surgery. To determine which OCT bio-markers are most useful in this regard and where future studies may apply more emphasis.

METHODS

An extensive search of the PubMed database was performed for studies investigating this relationship. Key search terms included: idiopathic, epiretinal membrane, surgery, peel, vitrectomy, vision, outcomes, visual acuity, ocular coherence tomography, central foveal thickness, foveal contour, foveal morphology, ectopic inner foveal layers, inner retinal layers, inner retinal irregularity index, outer retinal layers, ellipsoid zone, interdigitation zone, photoreceptor outer segment length, central bouquet abnormality, staging, choroidoscleral irregularity, ganglion cell and nerve fibre layers, inner and outer plexiform layers, inner and outer nuclear layers. Forty-nine peer-reviewed articles were included in this review. These consisted of 28 retrospective studies [1-3,13,16-18,20,23-29,32-36,38,40,42-47], 17 prospective studies[6-12,14,19,21,22,30,31,37,41,48,49], 2 reviews [4,39] and 2 systematic reviews [5,15].

CONCLUSION

The weight of literary evidence seems to support photoreceptor integrity as the most consistent OCT marker of better postoperative visual acuity. This includes analysis of ellipsoid and interdigitation zones as well as photoreceptor outer segment length. However, the newer OCT staging system proposed by Govetto et al. (2017) fulfils a need for a clinically useful and evidence-based OCT classification. It may be the way forward in prognosticating ERM surgical outcomes by preoperative stratification. There is insufficient evidence to suggest the other discussed parameters in this review as useful prognosticators of postoperative visual acuity.

Effects of Ectopic Inner Foveal Layers on Foveal Configuration and Visual Function after idiopathic Epiretinal Membrane Surgery

PURPOSE

To investigate the effects of ectopic inner foveal layers (EIFLs) on foveal configuration recovery and visual acuity (VA) after idiopathic epiretinal membrane (iERM) removal and analyze the relationship of foveal configuration recovery between 1-month and long-term postoperatively.

METHODS

This retrospective study included 216 consecutive eyes with iERM that underwent vitrectomy surgery. A comprehensive ophthalmic examination was performed for all patients before and 1, 4,10, and 24 months after surgery. We observed the postoperative anatomical and functional recovery of eyes with and without EIFLs and analyzed the association between short-term and long-term anatomical recovery.

RESULTS

The presence of EIFL was associated with severe preoperative visual damage (P＜0.001) and was considered as a negative factor for postoperative foveal depression recovery (P＜0.001). No significant difference was found in postoperative BCVA between the eyes with and without EIFLs (P=0.442). For eyes with stage II ERMs, 17.6% developed EIFLs postoperatively, which did not affect the final BCVA. Overall, 24.5% of ERMs restored the foveal configurations at 1 month postoperatively, and 14.7% continued recovering during the follow-up. Foveal structure recovery in eyes with EIFLs was associated with earlier stage, fewer microcystic macular edema, complete IZ layer, and a thinner CFT (All P＜0.05) at 1-month postoperatively.

CONCLUSIONS

The EIFL is associated with severe preoperative visual damage and is a negative factor for postoperative anatomical recovery, but it is a minor factor for postoperative VA. We also found an association of foveal configuration recovery between 1-month and long-term after surgery.

Efficacy of Combined Vitrectomy with Intravitreal Corticosteroid Injection for Idiopathic Epiretinal Membrane Removal on Anatomical and Functional Outcomes: A Meta-analysis

BACKGROUND

Macular edema can be a cause of visual loss in eyes undergoing vitrectomy with epiretinal membrane(ERM) peeling.

OBJECTIVE

To evaluate the efficacy of combined vitrectomy with intravitreal corticosteroid injection for ERM.

METHODS

We conducted a systematic literature review by searching PubMed, Embase, and Medline up to December 2020 for studies that evaluated the effect of intravitreal corticosteroid injection during vitrectomy for ERM. Follow-up data on postoperative best-corrected visual acuity (BCVA) and central macular thickness (CMT) were collected and pooled using the standard mean deviation (SMD) with the corresponding 95% confidence interval (CI). Heterogeneity was statistically quantified using I2 statistics, and a meta-analysis was performed using a random-effects model.

RESULTS

Eight studies provided data on a total sample of 443 eyes. The meta-analysis revealed that concomitant intravitreal corticosteroid administration during vitrectomy contributed to a significant reduction in CMT than vitrectomy alone at 3 months after operation (pooled SMD = -0.353; 95% CI, -0.594 to -0.111; p = 0.004). However, between the two groups, no significant difference was found in CMT reduction at 1 and 6 months after operation and in postoperative BCVA improvement at 1, 3, and 6 months after operation.

CONCLUSION

Combined treatment with vitrectomy and intravitreal corticosteroid injection may accelerate CMT reduction 3 months after ERM surgery. However, it did not result in a significant change in CMT and BCVA compared with vitrectomy alone at the end of follow-up.

Ectopic inner foveal layer as a factor associated with metamorphopsia after vitrectomy for epiretinal membrane

PURPOSE

To analyse the relationship between the extent of metamorphopsia and optical coherence tomography (OCT) parameters including the ectopic inner foveal layer (EIFL) in patients with epiretinal membrane (ERM) who underwent pars plana vitrectomy (PPV).

METHODS

This study included 63 eyes of 62 patients who underwent PPV for ERM. Metamorphopsia was assessed by measuring the metamorphopsia score for vertical lines (MV) and metamorphopsia score for horizontal lines (MH) using M-CHARTS. Central retinal thickness (CRT), EIFL thickness and disruption of outer retinal layers were measured before and after surgery, and the relationship of these parameters with metamorphopsia scores at 3 months after vitrectomy was analysed.

RESULTS

Preoperative MV correlated with preoperative CRT and EIFL (p = 0.005 and 0.045 respectively). Postoperative MH correlated with preoperative CRT (p = 0.048), while postoperative MV correlated with preoperative CRT and EIFL (p = 0.002 and 0.0006 respectively). Postoperative MH correlated with postoperative CRT and EIFL (p = 0.001 and 0.002 respectively), and postoperative MV also correlated with postoperative CRT and EIFL (p = 0.0008 and < 0.0001 respectively). MH and MV did not correlate with outer retinal layer disruptions, both before and after vitrectomy. When multiple regression analysis was performed on preoperative and postoperative OCT parameters that correlated with postoperative metamorphopsia scores, only postoperative EIFL was identified as an independent factor associated with postoperative MV (p = 0.042).

CONCLUSION

When PPV was conducted for ERM, postoperative EIFL was found to be a significant factor associated with postoperative metamorphopsia score.

Macular pigment optical density assessed by heterochromatic flicker photometry in eyes affected by primary epiretinal membrane

PURPOSE

To compare macular pigment optical density (MPOD) in healthy eyes vs eyes affected by primary epiretinal membrane (ERM) in different stages and to assess the relation between MPOD and optical coherence tomography findings.

METHODS

Prospective cross-sectional study of 62 eyes from 62 patients affected by unilateral primary ERM. Contralateral healthy eyes from the same patients were used as a control group. Main outcome measures were MPOD, ERM stage, central foveal thickness (CFT), outer nuclear layer thickness (ONLT), integrity of outer retinal bands (ORB) and presence of Central Bouquet (CB) abnormalities.

RESULTS

In the study group mean CFT was 444±75 µm and mean ONLT was 245±40 µm, while in the control group mean CFT was 230±21 µm and mean ONLT was 102±14 µm (p<0.001). Mean MPOD was 0.86±0.07 in eyes with ERM and 0.48±0.09 in contralateral healthy eyes (p<0.001). MPOD was associated with CFT (p=0.006) and ONLT (p<0.001) while no significant associations were observed between MPOD and ORB integrity (p=0.14) and CB abnormalities (p=0.08).

CONCLUSIONS

MPOD increased in eyes affected by primary ERM proportionally to CFT and, especially, ONLT. Probably, centripetal forces exerted by ERM contraction on the retinal surface lead to a progressive foveal packing of foveal Muller cells.

Influence of postoperative ectopic inner foveal layer on visual function after removal of idiopathic epiretinal membrane

Purpose

To investigate the functional and anatomical parameters and their postoperative changes according to the ectopic inner foveal layer (EIFL) staging scheme for idiopathic epiretinal membrane (ERM).

Methods

In this prospective study, patients with idiopathic ERM underwent pars plana vitrectomy and ERM removal, and were followed-up for 6 months. The associations of EIFL with pre- and postoperative functional and anatomical parameters were analyzed.

Results

A total of 84 eyes (84 patients) were included: 39 (46.4%), 33 (39.3%), and 12 (14.3%) as EIFL stages 2, 3, and 4, respectively. At 6 months after surgery, the mean best-corrected visual acuity (BCVA) significantly improved in all EIFL stages (P ≤ 0.003); however, metamorphopsia improved only in eyes with EIFL stage 2 (P = 0.039) and 3 (P = 0.011). The aniseikonia and foveal avascular zone (FAZ) area showed no significant postoperative changes in any of the EIFL stages. Both preoperatively and during 6 months after surgery, the EIFL stage showed a significant correlation with BCVA (P ≤ 0.033), metamorphopsia (P ≤ 0.008), central macular thickness (P < 0.001), and FAZ parameters (P ≤ 0.016) at each time point, but not with aniseikonia. Significant correlations of EIFL thickness with BCVA (P = 0.028) and metamorphopsia (P = 0.006) before surgery were not persistent after surgery.

Conclusion

Both pre- and postoperatively, the staging of EIFL, rather than its thickness, is a simple and adequate surrogate marker for visual acuity and metamorphopsia in eyes with idiopathic ERM.

Optical coherence tomography biomarkers for visual acuity in patients with idiopathic epiretinal membrane

PURPOSE

To investigate the correlation between outer and inner retina optical coherence tomography (OCT) biomarkers and visual acuity in patients with idiopathic epiretinal membrane (iERM) and identify which of them may be predictive of visual function.

METHODS

A retrospective cross-sectional single-center study was conducted that included patients diagnosed with iERM. Spectral domain OCT images were obtained and assessed qualitatively and quantitatively. The association of OCT parameters with best corrected visual acuity was analyzed.

RESULTS

Charts of 97 eyes of 97 patients were reviewed. Central foveal thickness, maximal retinal thickness (MRT), photoreceptor outer segment length, outer foveal thickness, ganglion cell-inner plexiform layer complex thickening, inner retinal thickness and inner retinal layer irregularity index were among the major outcome measures. OCT scans were also assessed for the presence of cotton ball sign, ellipsoid zone disruption, ectopic inner foveal layer, disorganization of retinal inner layers (DRIL), intraretinal fluid, subretinal fluid (SRF) and epimacular membrane rip. Univariate analysis showed statistically significant association between all the aforementioned parameters with worse vision, except for cotton ball sign and SRF. Multivariate analysis found that MRT and severe DRIL were strongly correlated with worse vision (p < 0.001).

CONCLUSION

MRT and severe DRIL should be considered as negative prognostic factors for visual acuity.

Pars Plana Vitrectomy for Idiopathic Epiretinal Membrane: Optical Coherence Tomography Biomarkers of Visual Outcomes in 322 Eyes

OBJECTIVE

To investigate optical coherence tomography (OCT)-based biomarkers of visual acuity (VA) in eyes with idiopathic epiretinal membranes (ERM) undergoing surgical intervention.

PURPOSE

To assess surgical outcomes of pars plana vitrectomy (PPV) and membrane peel (MP) surgery in eyes with idiopathic ERM and identify potential imaging-based biomarkers of vision outcomes.

METHODS

Retrospective, consecutive case series of eyes with idiopathic ERM that underwent PPV and MP surgery between 1/1/2017 and 1/1/2019. A previously described ERM grading scale was utilized for OCT analysis. The primary outcome was VA at post-operative month 6 and final follow-up. A secondary outcome was the association of OCT structural features, including ectopic inner foveal layers (EIFL), inner microcystoid changes, and ellipsoid zone (EZ) disruption, with VA outcomes.

RESULTS

A total of 322 eyes with idiopathic ERM were included. Mean (± SD) follow-up was 506.6 ± 324.6 days after MP surgery. VA improved from logMAR 0.49 ± 0.27 (Snellen 20/61) pre-MP to 0.41 ± 0.30 (Snellen 20/51, p< 0.001) at 6 months after MP and 0.31 ± 0.29 (Snellen 20/41, p<0.001) at final follow-up. A total of 21 (6.5%) eyes were graded as Stage 1, 38 (11.8%) as Stage 2, 188 (58.4%) as Stage 3, and 75 (23.3%) as Stage 4, with higher ERM stages associated with worse pre-MP VA (p<0.001). Presence of inner microcystoid changes was associated with worse pre-MP VA (p=0.04). Stage 4 ERM characteristics (p=0.03), presence of EZ disruption (p=0.01) at month 3, and presence of inner microcystoid changes at month 3 (p=0.02) were associated with worse VA at 6 months. Presence of EIFL was not associated with 6 month or final VA on multivariate analysis. When analyzed within defined age groups, patients older than 80 years old had worse final VA (p=0.02) and were more likely to have inner microcystoid changes on OCT (p=0.01).

CONCLUSIONS

VA improvement was noted after surgery in eyes with idiopathic ERM across all stages. Pre-operative stage 4 characteristics were associated with worse VA at 6 months. Post-operative inner microcystoid changes and EZ disruption at month 3 were additional OCT biomarkers associated with worse 6 month and final VA outcomes.

Swept-source OCT reduces the risk of axial length measurement errors in eyes with cataract and epiretinal membranes

AIMS

To compare the biometric data from partial coherence interferometry (PCI) and swept-source OCT (SS-OCT) in patients with age-related cataract and epiretinal membrane (ERM): ERM, ERM with foveoschisis and macular pseudohole.

METHODS

49 eyes of 49 subjects including 36 ERM, 9 ERM foveoschisis and 4 macular pseudohole were analysed to evaluate the axial length (AL) measurements and the presence of AL measurement errors, defined basing on the shape of the biometric output graphs and on the concordance of AL values between instruments. Eyes with ERM were divided in four stages according to OCT features (i.e. presence/absence of the foveal pit, presence of ectopic inner foveal layers, disrupted retinal layers).

RESULTS

The devices provided similar mean AL measurements in all subgroups, with differences <0.1 mm in 41/49 cases (83.6%). AL measurement errors were observed in ERM stages 3 and 4, characterized by ectopic inner foveal layers, and were significantly more frequent with the PCI (8/17, 47%) as compared with the SS-OCT device (2/17, 12%), p = 0.02. The refractive prediction error in cases with AL measurement errors was significantly greater using the PCI compared to the SS-OCT device (p<0.05).

CONCLUSION

Both devices provide reliable biometric data in the majority of patients and can be used in the preoperative assessment of patients with age-related cataract and ERM. In eyes with ectopic inner foveal layers, attention should be paid as AL measurement and refractive prediction errors may occur, more frequently with the PCI device.

MISALIGNMENT BETWEEN CENTER OF FOVEAL AVASCULAR ZONE AND CENTER OF FOVEAL PHOTORECEPTORS IN EYES WITH IDIOPATHIC EPIRETINAL MEMBRANE

PURPOSE

To determine the degree of misalignment between the center of foveal avascular zone and the center of foveal photoreceptors in eyes with an idiopathic epiretinal membrane (ERM).

METHODS

We reviewed the medical records of 61 eyes with an idiopathic ERM. A 3 × 3 mm area centered on the fovea was scanned with optical coherence tomography angiography before and at 6 months after surgery. The center of foveal avascular zone and the center of foveal photoreceptors were detected by en-face optical coherence tomography angiography images and sequential optical coherence tomography B-sections in the macular region. The presence or absence of ectopic inner foveal layers was also evaluated.

RESULTS

The mean distance from the center of foveal photoreceptors to the center of foveal avascular zone was 111.7 ± 106.8 µm in eyes with preoperative ERM. This distance was significantly correlated with the preoperative central foveal thickness (r = 0.33, P = 0.0104). Preoperatively, the ectopic inner foveal layers were present in 27 (44.3%) of 61 eyes. The foveal misalignment was greater in eyes with ectopic inner foveal layers than in those without ectopic inner foveal layers (158.6 ± 140.0 vs. 74.4 ± 45.4 µm, P < 0.0003). At 6 months after ERM surgery, the foveal misalignment was significantly reduced to 73.7 ± 48.0 µm (P = 0.0018).

CONCLUSION

Determining the degree of misalignment between the center of foveal avascular zone and the center of foveal photoreceptors might be a useful way to evaluate the degree of ERM traction.

Epiretinal membrane: A review

The prevalence of epiretinal membrane (ERM) is 7% to 11.8%, with increasing age being the most important risk factor. Although most ERM is idiopathic, common secondary causes include cataract surgery, retinal vascular disease, uveitis and retinal tears. The myofibroblastic pre-retinal cells are thought to transdifferentiate from glial and retinal pigment epithelial cells that reach the retinal surface via defects in the internal limiting membrane (ILM) or from the vitreous cavity. Grading schemes have evolved from clinical signs to ocular coherence tomography (OCT) based classification with associated features such as the cotton ball sign. Features predictive of better prognosis include absence of ectopic inner foveal layers, cystoid macular oedema, acquired vitelliform lesions and ellipsoid and cone outer segment termination defects. OCT-angiography shows reduced size of the foveal avascular zone. Vitrectomy with membrane peeling remains the mainstay of treatment for symptomatic ERMs. Additional ILM peeling reduces recurrence but is associated with anatomical changes including inner retinal dimpling.

The predictive value of ectopic inner retinal layer staging scheme for idiopathic epiretinal membrane: surgical results at 12 months

BACKGROUND/OBJECTIVES

To assess the effect of ectopic inner foveal layers (EIFL) based staging scheme, foveal avascular zone (FAZ) alterations and other microstructural optical coherence tomography (OCT) findings on visual function for patients undergoing idiopathic epiretinal membrane (iERM) surgery.

SUBJECTS/METHODS

In this retrospective study, patients who underwent 27 G pars plana vitrectomy (PPV) for idiopathic ERM with a minimum follow-up of 12 months were included. Preoperative and postoperative OCT scans, FAZ area measurements on en face OCT angiography images and mean retinal sensitivity (MRS) using microperimetry were recorded in all cases. The correlation of FAZ area, EIFL and other OCT parameters with preoperative and postoperative best-corrected visual acuity (BCVA) was analysed.

RESULTS

In all, 112 eyes of 112 patients were included. Visual acuity improvement was statistically significant in all four stages; however, differences between Stages 2, 3 and 4 ERMs remained significant (p < 0.05). The presence and thickness of the EIFL was associated with worse baseline (p = 0.013; p = 0.005, respectively) and final (p < 0.001 for both) BCVA. The presence of cystoid macular oedema was associated with worse BCVA at baseline (p = 0.027) and postoperative month-6 (p = 0.04). The mean FAZ area was significantly reduced in all stages of ERM compared with the fellow eyes (p < 0.05 for all). Postoperative retinal sensitivity improvement was statistically significant in Stage 1 and Stage 2.

CONCLUSION

The presence of EIFL is an independent predictor of worse postoperative BCVA. Accordingly, despite significant BCVA improvements in all stages of ERM, visual acuity gain remains limited in eyes with Stage 3 and Stage 4 ERM.

The visual outcomes of idiopathic epiretinal membrane removal in eyes with ectopic inner foveal layers and preserved macular segmentation

PURPOSE

To analyze the functional impact of ectopic inner foveal layers (EIFL), along with other clinical and optical coherence tomography biomarkers, on patients with epiretinal membrane (ERM) and preserved foveal layers' segmentation undergoing ERM removal.

METHODS

Retrospective review of consecutive patients with ERM who underwent pars plana vitrectomy with ERM peeling from December 2018 to December 2019. Baseline factors including age, gender, lens status, phacoemulsification at the time of surgery, tamponade agent, dye used for ERM and internal limiting membrane (ILM) enhancement, ILM peeling, best-corrected visual acuity (BCVA) and central macular thickness (CMT), presence and thickness of EIFL, thickness of outer nuclear layer (ONL), presence of a cotton ball, subfoveal state of photoreceptors, and presence of cystoid macular edema were included in a multivariable model having the BCVA at 12 months as the main outcome. The changes in EIFL and ONL thickness over time were also analyzed.

RESULTS

Fifty-one patients (58 eyes, 23 eyes in the no EIFL group, and 35 eyes in the EIFL group) were enrolled. The BCVA significantly improved over 12 months after surgery, regardless of the presence of EIFL (p < 0.001). Eyes with no EIFL had better BCVA at month 3 (p = 0.04), but this difference was no longer detectable at 6 and 12 months. The presence of EIFL was not associated with the final BCVA (p = 0.9), while the CMT at 12 months correlated with EIFL thickness (r = 0.8, p = 0.008).

CONCLUSION

Patients with EIFL could reach optimal visual acuity in the absence of disorganization of the inner retinal layers but should be warned of potentially longer healing times. None of the morphologic signs included in this study precluded good visual recovery on long-term follow-up.

Epiretinal membrane vitrectomy: outcomes with or without cataract surgery and a novel prognostic factor for cystoid macular edema

PURPOSE

To assess the outcomes of vitrectomy with or without cataract surgery for the treatment of idiopathic ERM in phakic eyes and evaluate predictors of functional and anatomical outcomes.

METHODS

Retrospective cohort of consecutive phakic ERM eyes distributed in three groups: a) combined (phacovitrectomy) group, b) PPV-only group, and c) consecutive group (PPV followed by cataract surgery). Main outcomes were final visual acuity (VA) and cystoid macular edema (CME) occurrence. Potential predictors of VA or CME included clinical variables and SD-OCT parameters.

RESULTS

A total of 108 eyes were included in this study. There were no differences in the final VA between consecutive and combined groups (0.22 vs 0.10 logMAR, p = 0.851). Twelve eyes from the combined group (23%) and one eye from the PPV-only group presented CME (p = 0.001). There were no differences between postoperative CME occurrence in combined versus consecutive group (12 vs 7, p = 0.38). The presence of cotton-ball sign predicted the development of CME [OR 2.86 (95%CI 1.01-8.18), p = 0.049] while separated ERM-ILM complex was found to be protective [OR 0.25 (95%CI 0.08-0.77), p = 0.015].

CONCLUSIONS

Functional and anatomical results of PPV with ERM and ILM peeling combined with cataract surgery was equivalent to the consecutive procedure, with both strategies being effective. Separated ERM-ILM complex has prognostic value in these patients, as its presence at baseline was found to be protective for postoperative CME.

Novel Optical Coherence Tomography Parameters as Prognostic Factors for Stage 3 Epiretinal Membranes

Purpose

We aimed to describe the visual prognosis of eyes with ectopic inner foveal layers (EIFLs) after epiretinal membrane (ERM) surgery.

Methods

This retrospective study enrolled patients diagnosed with stage 3 ERM based on the EIFL staging scheme who underwent ERM surgery with a minimum follow-up period of 12 months. Central foveal thickness (CFT), EIFL thickness, and the length of the ellipsoid zone defect were evaluated at baseline and at 1 month, 6 months, and 12 months after surgery based on pre- and postoperative swept-source optical coherence tomography (OCT) images. The association of EIFL thickness and other OCT parameters with pre- and postoperative best-corrected visual acuity (BCVA) was analyzed.

Results

Sixty-nine eyes with stage 3 ERMs were analyzed. Preoperative BCVA was correlated with preoperative CFT (r = 0.517, p < 0.001) and preoperative EIFL thickness (r = 0.652, p < 0.001). At 12 months, postoperative BCVA was correlated negatively with preoperative CFT (r = 0.470, p=0.016) and preoperative EIFL thickness (r = 0.582, p=0.004). The improvement in BCVA was not associated with postoperative reduction in CFT (p=0.06), although it was significantly associated with postoperative reduction in EIFL thickness (r = 0.635, p=0.007).

Conclusions

EIFL thickness should be considered a negative prognostic factor for postoperative anatomical and functional recovery in patients with stage 3 ERMs.

Long-Term Outcome of Epiretinal Membrane Surgery in Patients with Internal Limiting Membrane Dehiscence

PURPOSE

To identify the effect of internal limiting membrane (ILM) dehiscence on surgical outcomes in eyes that have undergone epiretinal membrane (ERM) removal.

METHODS

Consecutive eyes with performed vitrectomy for ERM removal were included. Subjects were divided into two groups: patients with ILM dehiscence (group 1) and without ILM dehiscence (group 2). The best-corrected visual acuity (BCVA) and retinal layer thickness before and after surgery were compared between the two groups.

RESULTS

A total of 86 eyes were enrolled. Forty-six eyes (53.5%) showed ILM dehiscence before surgery. The baseline BCVAs were 0.46 ± 0.29 and 0.45 ± 0.25 in groups 1 and 2, respectively (p = 0.801). The BCVAs at 3, 6, and 12 months after surgery differed significantly between the two groups. The subfoveal thickness and inner retinal layer thickness (IRLT) of group 1 vs. 2 were 507.4 ± 80.0 vs. 417.6 ± 63.6 μm, and 270.2 ± 74.3 vs. 182.6 ± 60.4 μm, respectively (both p < 0.001). These differences between the groups remained significant until 12 months after surgery. In multivariate analyses, the location of ILM dehiscence (B = -0.105, p = 0.034) and final IRLT (B = 0.001, p = 0.046) were significant factors affecting the final BCVA.

CONCLUSIONS

ILM dehiscence is a relatively common finding and associated with preoperative and postoperative increased IRLT, which results in worse surgical outcomes compared to the absence of ILM dehiscence in patients with ERM. Additionally, the final BCVA was significantly affected by its location and final IRLT in patients with ILM dehiscence.

Elevated M2 Macrophage Markers in Epiretinal Membranes With Ectopic Inner Foveal Layers

Purpose

To analyze the differences in the vitreous cytokine profiles in epiretinal membrane eyes with and without an ectopic inner foveal layer (EIFL).

Methods

Sixty eyes with epiretinal membrane (32 eyes without EIFL and 28 eyes with EIFL) were included. The vitreous samples were collected during surgery for epiretinal membrane. The cytokine levels of the vitreous were measured using a multiplex bead analysis.

Results

The mean logMAR visual acuity was worse (0.42 vs. 0.37; P = 0.331) and the central foveal thickness was higher in the EIFL group (496.9 µm vs. 434.2 µm; P = 0.007) than they were in the group without EIFL. The mean EIFL thickness was 164.1 ± 67.7 µm in the EIFL group. On multiplex analysis of the vitreous cytokines, the levels of CD163 (21529 pg/dL vs. 10877 pg/dL; P = 0.002) and macrophage colony-stimulating factor (206 pg/dL vs. 159 pg/dL, P = 0.004) were significantly higher in the EIFL group than they were in the group without EIFL.

Conclusions

Eyes with EIFL had increased vitreous levels of M2 macrophage markers. The activation of glial cell proliferation by M2 macrophages may contribute to EIFL formation.