Idiopathic epiretinal membrane

Impact of retinal traction induced by epiretinal membrane on aniseikonia

We investigated the effect of retinal traction caused by epiretinal membranes (ERMs) on aniseikonia and retinal microstructures in 81 unilateral ERMs. Retinal traction was quantified by measuring the maximum depth of the retinal fold (MDRF) using en face optical coherence tomography (OCT) images. Measurements included the mean inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), central retinal thickness (CRT), and interocular ratios of the foveal avascular zone (FAZ) area (FAZ ratio). Significant correlations were found between the preoperative MDRF and preoperative aniseikonia (P < 0.001), INL thickness (P < 0.001), CRT (P < 0.001), and FAZ ratio (P = 0.003). Preoperative aniseikonia was significantly correlated with preoperative INL and OPL-ONL thicknesses (P < 0.001 and P = 0.020, respectively) and CRT (P = 0.003). Multiple regression analysis revealed that preoperative aniseikonia was significantly associated with preoperative MDRF, INL, and OPL-ONL thicknesses (P = 0.029, 0.006, and 0.006, respectively). Twenty-nine eyes underwent membrane peeling, resolving all retinal folds 6 months postoperatively. A significant correlation was observed between preoperative MDRF and postoperative aniseikonia (P = 0.011). Our findings suggest that retinal traction by ERM is significantly associated with aniseikonia both pre- and postoperatively, alongside other OCT parameters.

Preoperative Widefield Swept-Source Optical Coherence Tomography Versus Intraoperative Findings in Detecting Posterior Vitreous Detachment

Purpose

To assess the accuracy of swept-source optical coherence tomography (SS-OCT) in detecting complete posterior vitreous detachment (PVD) in comparison with intraoperative findings.

Methods

The retrospective study included 145 eyes of 145 consecutive patients who underwent surgery for epiretinal membranes or macular holes. Within a week prior to surgery, PVD status was evaluated by SS-OCT with a depth of field of 3 mm and a capture window of 16 × 8 mm. Complete PVD was identified when the hyaloid condensation was visible clearly on any B-scan or when the vitreous cortex reflectivity was not visible on all 33 B-scans. Sensitivity, specificity, positive predictive value, and negative predictive value of SS-OCT for detection of complete PVD were then compared with those evaluated during a triamcinolone acetonide-assisted vitrectomy.

Results

Of the 101 eyes diagnosed as complete PVD by SS-OCT preoperatively, 97 eyes were found to have complete PVD and four eyes were found to have attached vitreous intraoperatively. Of the 44 eyes categorized as attached vitreous by SS-OCT preoperatively, 43 eyes were graded as attached vitreous and one eye was graded as complete PVD during surgery. The sensitivity of SS-OCT for detecting complete PVD was 99.0% and the specificity was 91.5%. The positive predictive value and the negative predictive value were 96.0% and 97.7%, respectively.

Conclusions

Widefield (16 × 8 mm) SS-OCT showed high accuracy for the diagnosis of complete PVD in patients with epiretinal membranes or macular holes.

Translational Relevance

Widefield SS-OCT has great potential to evaluate PVD status preoperatively and explore the mechanisms of vitreoretinal diseases.

TLR2 and TLR4 Are Expressed in Epiretinal Membranes: Possible Links with Vitreous Levels of Complement Fragments and DAMP-Related Proteins

Previous studies reported the expression of toll-like receptors (TLRs), merely TLR2 and TLR4, and complement fragments (C3a, C5b9) in vitreoretinal disorders. Other than pathogens, TLRs can recognize endogenous products of tissue remodeling as damage-associated molecular pattern (DAMPs). The aim of this study was to confirm the expression of TLR2 and TLR4 in the fibrocellular membranes and vitreal fluids (soluble TLRs) of patients suffering of epiretinal membranes (ERMs) and assess their association with disease severity, complement fragments and inflammatory profiles. Twenty (n = 20) ERMs and twelve (n = 12) vitreous samples were collected at the time of the vitrectomy. Different severity-staged ERMs were processed for: immunolocalization (IF), transcriptomic (RT-PCR) and proteomics (ELISA, IP/WB, Protein Chip Array) analysis. The investigation of targets included TLR2, TLR4, C3a, C5b9, a few selected inflammatory biomarkers (Eotaxin-2, Rantes, Vascular Endothelial Growth Factor (VEGFA), Vascular Endothelial Growth Factor receptor (VEGFR2), Interferon-γ (IFNγ), Interleukin (IL1β, IL12p40/p70)) and a restricted panel of matrix enzymes (Matrix metalloproteinases (MMPs)/Tissue Inhibitor of Metallo-Proteinases (TIMPs)). A reduced cellularity was observed as function of ERM severity. TLR2, TLR4 and myD88 transcripts/proteins were detected in membranes and decreased upon disease severity. The levels of soluble TLR2 and TLR4, as well as C3a, C5b9, Eotaxin-2, Rantes, VEGFA, VEGFR2, IFNγ, IL1β, IL12p40/p70, MMP7 and TIMP2 levels were changed in vitreal samples. Significant correlations were observed between TLRs and complement fragments and between TLRs and some inflammatory mediators. Our findings pointed at TLR2 and TLR4 over-expression at early stages of ERM formation, suggesting the participation of the local immune response in the severity of disease. These activations at the early-stage of ERM formation suggest a potential persistence of innate immune response in the early phases of fibrocellular membrane formation.

Morphological Change in Optical Coherence Tomography and Functional Outcomes in Epiretinal Membrane Peeling with or without SF6 Tamponade

BACKGROUND

The present study compares the anatomical and functional outcomes (best-corrected visual acuity (BCVA) and central macular thickness (CMT)) among membrane peeling with or without SF6 tamponade in patients with epiretinal membrane.

METHODS

We retrospectively reviewed patients diagnosed with macular pucker who underwent pars plana vitrectomy and membrane peeling in a tertiary center in Taiwan from January 2021 to December 2022. Subjects were categorized into with or without SF6 tamponade groups (SF6 group and BSS group). Postoperative intraocular pressure and complications were documented. Logistic regression analyses were performed to identify the prognostic factors during follow-up.

RESULTS

A total of 89 eyes were enrolled, including 34 eyes in the BSS group and 55 eyes in the SF6 group. The mean age was 66 years old, and a female predilection was demonstrated. Both groups possessed statistically significant improvement in BCVA and CMT after the operation. There was no significant difference in CMT between the groups at any time of observation, yet we observed significant differences in baseline BCVA and BCVA at last follow-up among the two groups. Both groups yielded an approximate enhancement of LogMAR 0.3 in BCVA postoperatively. There was no significant difference noted in postoperative IOP between the two groups.

CONCLUSION

Membrane peeling with or without SF6 tamponade yields comparable outcomes anatomically and functionally. This may indicate that SF6 tamponade for idiopathic macular pucker surgery may not provide extra benefit, and therefore warrants reconsideration as standard procedure.

Proportion and risk factors of epiretinal membrane in residents of Brussels with versus without diabetes mellitus

PURPOSE

To compare the proportion of epiretinal membrane (ERM) between individuals with diabetes mellitus (DM) and without DM, who live in Brussels, to investigate possible risk factors for ERM formation and to compare the results with the ones of large population studies.

METHODS

Participants were divided into two groups; 99 patients with DM (group A) and 103 individuals without DM (group B). All participants underwent an undilated 7-field color fundus photography and a spectral domain optical coherence tomography (SD-OCT). Age, gender, race, type of diabetes, duration of medical treatment of diabetes, HbA1C rate, smoking, previous cataract surgery and educational level were investigated as possible risk factors.

RESULTS

Epiretinal membrane was detected in 17.2% of group A and in 11.7% of group B participants. The difference is not statistically significant (χ2 (1) = 1.252, p = 0.263). The proportion of ERM was significantly associated with age in both groups (p = .009 and p < .001 respectively), as well as with smoking (p = .023) and previous cataract surgery (p = .028) in patients with DM.

CONCLUSION

There is no statistically significant difference of ERM proportion between the two groups of the study. Age was recognized as a risk factor for both groups, while smoking and previous cataract surgery were identified as predictors only for diabetics.

Preoperative Visual Acuity Thresholds in Pars Plana Vitrectomy for Epiretinal Membrane: A Systematic Review

BACKGROUND AND OBJECTIVE

This review consolidates findings from studies that used a preoperative visual acuity (VA) threshold as an indication for epiretinal membrane (ERM) surgery.

METHODS

The literature was systematically searched using Ovid MEDLINE, EMBASE, and Cochrane Library from January 2000 to October 2022 to select studies reporting on pars plana vitrectomy (PPV) for ERM that used a preoperative VA threshold as an inclusion criterion. Primary outcomes were final best-corrected visual acuity (BCVA) and change in BCVA relative to baseline. Secondary outcomes included risk of intra- and postoperative complications.

RESULTS

A total of 639 eyes from seven studies were included. The most liberal preoperative VA threshold was 20/28.5 or worse, whereas the most conservative threshold was worse than 20/60. The mean preoperative BCVA was 0.55 logarithm of the minimum angle of resolution (logMAR) (∼20/70), and the mean postoperative BCVA was 0.35 logMAR (∼20/45). Generally, VA improved relative to baseline, regardless of the preoperative VA threshold. The smallest improvement in VA was observed in a study where the pre-operative VA to consider surgery was liberal (20/30 or worse), whereas the greatest VA improvement was observed in a study that used a conservative preoperative VA threshold (worse than 20/60).

CONCLUSIONS

The greatest improvement in BCVA was observed in studies where a conservative pre-operative VA threshold was used. The decision to operate should involve a patient-centered approach with a thorough discussion of the risks and benefits of PPV, regardless of the preoperative VA threshold used. [Ophthalmic Surg Lasers Imaging Retina 2024;55:400-407.].

Epiretinal membranes in patients with uveitis: an update on the current state of management

PURPOSE

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up, and therapeutic approach of uveitic epiretinal membranes (ERM).

METHODS

A thorough investigation of the literature was conducted using the PubMed database. Additionally, a complementary search was carried out on Google Scholar to ensure the inclusion of all relevant items in the collection.

RESULTS

ERM is an abnormal layer at the vitreoretinal interface, resulting from myofibroblastic cell proliferation along the inner surface of the central retina, causing visual impairment. Known by various names, ERM has diverse causes, including idiopathic or secondary factors, with ophthalmic imaging techniques like OCT improving detection. In uveitis, ERM occurrence is common, and surgical intervention involves pars plana vitrectomy with ERM peeling, although debates persist on optimal approaches.

CONCLUSIONS

Histopathological studies and OCT advancements improved ERM understanding, revealing a diverse group of diseases without a unified model. Consensus supports surgery for uveitic ERM in progressive cases, but variability requires careful consideration and effective inflammation management. OCT biomarkers, deep learning, and surgical advances may enhance outcomes, and medical interventions and robotics show promise for early ERM intervention.

Role of Vitreous Detachment in Epiretinal Membrane Peeling: A Multimodal Imaging and Microperimetry Study

Background: To investigate anatomical and functional changes of the macula caused by epiretinal membrane (ERM) peeling procedures in patients with or without posterior vitreous detachment (PVD). Methods: This is a multicentric prospective observational study on thirty-seven (37) patients affected by symptomatic ERM who underwent 25-gauge pars plana vitrectomy (PPV), induction of a PVD (as needed) and peeling of both the internal limiting membrane (ILM) and ERM. Optical coherence tomography-angiography (OCT-A) (RS 3000, Nidek, Japan) and microperimetry (MP-3, Nidek, Japan) were performed; central retinal thickness (CRT), foveal avascular zone (FAZ) area and perimeter, vessel density and perfusion density, retinal sensitivity and fixation stability (as a total mean retinal sensitivity (MRS), and MRS in the ellipse area and bivariate contour ellipse area (BCEA)) were recorded at baseline and up to postoperative month 3. Results: Eyes were classified as having complete PVD (51.4%) or incomplete PVD (48.6%). At baseline, patients with incomplete PVD had worse best-corrected distance visual acuity (BCDVA), total MRS, MRS in the ellipse area and BCEA, and higher CRT than patients with complete PVD. At month 3, the differences in BCDVA between the two groups remained statistically significant, with patients with incomplete PVD having worse results (difference: 0.199 logMAR, p < 0.001). The difference in the MRS in the ellipse area was statistically significant at month 3 (-3.378 Db, p = 0.035), with greater improvement in patients with complete PVD. Conclusions: Our study shows that patients with incomplete PVD have worse conditions at baseline than patients with complete PVD, and the differences in visual acuity and retinal sensitivity were maintained postoperatively.

Fingerprint sign of the Henle fibre layer in epiretinal membrane: a cross-sectional and longitudinal study

PURPOSE

To investigate the incidence and distribution of fingerprint-like microwaves in the Henle fibre layer (HFL) of the eyes with epiretinal membrane (ERM).

METHODS

Patients with idiopathic ERM were included. The fingerprint sign was defined using en-face optical coherence tomography images of the HFL, and its extent was classified into three grades.

RESULTS

At baseline, fingerprint sign was found in 70 of 83 (84.3%) eyes with ERM and was more frequently observed in eyes with a higher ERM stage (P < 0.001). Its extent increased (P < 0.001) with an increase in ERM stage or the central macular thickness (P < 0.001). Best corrected visual acuity (BCVA) was worse in eyes with a fingerprint sign than in those without (P = 0.024). Metamorphopsia was more common in eyes with a greater extent of fingerprint-like microwaves (P = 0.048). The fingerprint sign persisted over a mean follow-up period of 18.0 ± 23.3 without surgery. In 45 eyes that underwent surgery, the extent of fingerprint-like microwaves decreased at 1.2 months (P = 0.001), and further decreased at 13.7 months postoperatively (P = 0.019). However, the proportion of eyes with a fingerprint sign after surgery was similar to that observed preoperatively (P = 0.912).

CONCLUSIONS

Fingerprint-like microwaves were commonly found in eyes with ERM and were associated with ERM severity and BCVA. The microwaves remained long after surgery, although their extent may have decreased after the ERM was resolved. These results suggest that ERM traction may cause long-lasting changes in the HFL.

Visual outcomes and complications of combined versus sequential pars plana vitrectomy and phacoemulsification for epiretinal membrane

BACKGROUND

Symptomatic epiretinal membrane (ERM) often requires surgical intervention via pars plana vitrectomy (PPV), for which cataract development is a common complication. There is insufficient data on the visual outcomes and complications of combined phacovitrectomy (COMB) in comparison to sequential PPV with deferred cataract surgery (SEQ) for ERM.

METHODS

A retrospective dataset analysis of 8 National Health Service ophthalmology departments. The main outcome measures were postoperative visual acuity (VA), operative complications, postoperative cystoid macular oedema (CMO) and recurrent ERM.

RESULTS

We included 898 and 299 eyes in the COMB and SEQ groups, respectively. Both procedures resulted in significantly better VA across all follow-up intervals (24 weeks). The proportion of eyes with Snellen VA of at least 20/40 at 12-24 weeks was comparable in both groups (47.8% [COMB] vs. 54.7% [SEQ], p = 0.4456). More eyes in the COMB group experienced posterior capsular rupture (2.9% vs. 0%, p = 0.0009) and iatrogenic retinal trauma (2.4% vs. 0%, p = 0.0023). However, regression analysis revealed that combined surgery did not predict either complication. There were no significant differences in the rates of CMO (6.5% [COMB] vs. 9% [SEQ], p = 0.1522) and recurrent ERM (2.1% [COMB] vs. 3.3% [SEQ], p = 0.2758) between both groups.

CONCLUSION

Both combined and sequential procedures are comparably effective and safe means for managing eyes with ERM.

Idiopathic Epiretinal Membranes - Pathophysiology, Classifications and OCT-Biomarkers

Epiretinal membranes (ERMs) are a common finding in patients with increasing age. Diagnosis and treatment of ERMs have changed dramatically in recent years due to technological advances in ophthalmological care. In recent years, tomographic imaging has allowed for accurate visualization of ERMs and contributed to the growing understanding of the pathophysiology of this condition. The literature review conducted here summarizes recent innovations in diagnosis, classification, and treatment of idiopathic ERMs and specifically addresses novel optical coherence tomography (OCT) biomarkers that allow for the generation of prognoses regarding the clinical postoperative outcome.

Analysing early changes of photoreceptor layer thickness following surgery in eyes with epiretinal membranes

BACKGROUND/OBJECTIVES

To analyse short-term changes of mean photoreceptor thickness (PRT) on the ETDRS-grid after vitrectomy and membrane peeling in patients with epiretinal membrane (ERM).

SUBJECTS/METHODS

Forty-eight patients with idiopathic ERM were included in this prospective study. Study examinations comprised best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) before surgery, 1 week (W1), 1 month (M1) and 3 months (M3) after surgery. Mean PRT was assessed using an automated algorithm and correlated with BCVA and central retinal thickness (CRT).

RESULTS

Regarding PRT changes of the study eye in comparison to baseline values, a significant decrease at W1 in the 1 mm, 3 mm and 6 mm area (all p-values < 0.001), at M1 (p = 0.009) and M3 (p = 0.019) in the central 1 mm area, a significant increase at M3 in the 6 mm area (p < 0.001), but no significant change at M1 in the 3 mm and 6 mm area and M3 in the 3 mm area (all p-values > 0.05) were observed. BCVA increased significantly from baseline to M3 (0.3LogMAR-0.15LogMAR, Snellen equivalent = 20/40-20/28 respectively; p < 0.001). There was no correlation between baseline PRT and BCVA at any visit after surgery, nor between PRT and BCVA at any visit (all p-values > 0.05). Decrease in PRT in the 1 mm (p < 0.001), 3 mm (p = 0.013) and 6 mm (p = 0.034) area after one week correlated with the increase in CRT (449.9 µm-462.2 µm).

CONCLUSIONS

Although the photoreceptor layer is morphologically affected by ERMs and after their surgical removal, it is not correlated to BCVA. Thus, patients with photoreceptor layer alterations due to ERM may still benefit from surgery and achieve good functional rehabilitation thereafter.

Subthreshold micropulse laser therapy for early postoperative macular thickening following surgical removal of epiretinal membrane

BACKGROUND

This study aimed to investigate the functional and anatomical outcomes of subthreshold micropulse laser (SMPL) therapy in eyes with early postoperative macular thickening after idiopathic epiretinal membrane (iERM) removal.

METHODS

This was a prospective and interventional study. Forty-eight eyes from 48 patients with macular edema at 1 month after iERM removal were randomly divided into two groups. Patients in the SMPL group (n = 24) received SMPL therapy while no special intervention was used for the observation group (n = 24). Baseline demographic data and clinical findings before and at 1 and 3 months after SMPL treatment or observation, including best-corrected visual acuity (BCVA) and the changes in central subfield thickness (CST) and average macular thickness (AMT), were analyzed.

RESULTS

An improvement in BCVA with a decrease in CST and AMT from baseline to the 3-month follow-ups were observed in both SMPL and observation groups. No significant difference in BCVA was observed between the SMPL group and observation group either in the 1-month (0.26 [0.15, 0.52] vs. 0.26 [0.15, 0.39], P = 0.852) or the 3-month (0.15 [0.10, 0.30] vs. 0.23 [0.15, 0.30], P = 0.329) follow-up. There was a greater reduction in CST in the SMPL group versus observation group between baseline and the 3-month follow-up (-77.8 ± 72.3 μm vs. -45.0 ± 46.9 μm, P = 0.049). The alteration in AMT did not differ between the two groups in either 1-month (-16.5 ± 20.1 μm vs. -19.7 ± 16.3 μm, P = 0.547) or 3-month (-36.9 ± 26.9 μm vs. -34.0 ± 20.1 μm, P = 0.678) follow-up.

CONCLUSIONS

SMPL therapy led to a significant decrease in CST at the 3-month follow-up while did not significantly improve the visual acuity in patients with postoperative macular thickening following iERM surgery.

TRIAL REGISTRATION

The study was registered on Aug 27, 2020 (Trial Registration Number: ChiCTR 2000037227).

Mechanical impact of epiretinal membranes on the retina utilizing finite element analysis

BACKGROUND AND OBJECTIVE

Epiretinal membrane (ERM) is a transparent membrane that forms on the surface of the neurosensory retina, causing tangential traction on the retinal surface, which may contribute to cell proliferation and contraction. Epiretinal membranes (ERMs) may be asymptomatic in some patients, while in others the membranes can progress, resulting in macular thickening and macular traction, thus distorting and inducing loss of central visual function and metamorphopsia. Currently, treatment options include follow-up or pars plana vitrectomy with an ERM peel, aiming to relieve the macular traction and improve vision and metamorphopsia. No specific criteria exist for predicting which patients might progress and need early surgery to improve and maintain good vision. The decision for surgery is based on the individual's symptoms and the physician's judgment. This study aimed to evaluate the mechanical impact in terms of stress and deformations of the ERM and to qualitatively compare them with the clinical progression of fovea thickening observed through optical coherence tomography (OCT) images.

METHODS

Numerical simulation on a three-dimensional geometrical retina and ERM model was applied to isolate factors that can be used to predict its progression and prognosis. OCT images of 14 patients with ERM were used to derive the fovea thickness progression before and after vitrectomy surgery with ERM peeling.

RESULTS

The results clearly show that the increase in ERM contractility level increases the developed stress at the fovea, which spreads and advances toward its base. The highest stress level (2.1 kPa) was developed at the highest and asymmetric contractility, producing non-uniform distributed deformations that distort the fovea structure.

CONCLUSIONS

These findings imply that high and asymmetric ERM contractility should be evaluated clinically as a factor that might signal the need for early vitrectomy surgery to avoid irreversible visual loss. Moreover, the OCT images revealed that in some cases, the thickness of the fovea indeed remains high, even after ∼12 months postoperatively, which also indicates that the deformation of the fovea in these cases is irreversible.

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.

Epiretinal membrane development after Ex-Press glaucoma filtration device implant: 2-year results of a case control study

BACKGROUND

The most common retinal complications after glaucoma surgery are choroidal detachment, hypotony maculopathy, malignant glaucoma, vitreous hemorrhage, endophthalmitis and retinal detachment. However, if glaucoma surgery is a risk factor for the ERM development needs to be clarified. This study aims to assess the incidence of epiretinal membrane (ERM) in 2 years of follow-up in patients with primary open-angle glaucoma (POAG) treated with Ex-Press shunt implant.

METHODS

A prospective, consecutive, single-center, case-control study. We enrolled patients affected by POAG and scheduled for Ex-Press device implant with or without concomitant cataract surgery. The control group was the contralateral eyes which continues anti-glaucomatous eyedrops. Complete ophthalmologic evaluation and spectral-domain optical coherence tomography were performed before surgery, at 6 months and 24 months of follow-up.

RESULTS

Eighty-two eyes of 41 consecutive patients, 18 males and 23 females with a mean age of 70, 29 ± 8,45, were analyzed at 24 months. 39.1% of eyes developed ERM: 29.3% were cellophane macular reflex (CMR) and 9.8% were pre-macular fibrosis (PMF). In the control group, 19.5% of eyes developed ERM: 17.1% were CMR and 2.4% were PMF. No statistically significant difference was reported (p = 0.121) between treated and control group. ERM development did not affect significantly the central foveal thickness (260.13 ± 35.01 μm at baseline, 265.03 ± 34.90 μm at 6 months and 275.18 ± 33.31 μm at 24 months) and macular volume (7.75 ± 0.43 mm3 at baseline, 7.77 ± 0.48 mm3 at 6 months and 7.77 ± 0.46 mm3 at 24 months), remained comparable to reported average measures in healthy individuals during the follow-up. Concomitant cataract surgery did not increase the ERM incidence.

CONCLUSION

Ex-Press implant may increase the ERM incidence regardless concomitant cataract surgery, accelerating or inducing a posterior vitreous detachment, such as other ocular surgical procedure. Nevertheless, the vast majority of ERM are CMR, not affecting the macular profile.

Japan-epiretinal membrane (J-ERM) registry: A prospective cohort study protocol investigating the surgical outcome of epiretinal membrane

BACKGROUND

Epiretinal membrane (ERM) causes visual impairment such as reduction in visual acuity and metamorphopsia due to retinal traction. With the improvement of optical coherence tomography (OCT) and microincision vitrectomy surgery (MIVS), the surgery of ERM has significantly advanced. However, there have been no large-scale studies on the following: (1) how to evaluate visual impairment in ERM, (2) the relationship between OCT findings and visual function, (3) when is the optimal timing of surgery, and (4) the relationship between the surgical instruments as well as techniques and prognosis. The purpose of this study was to obtain evidence regarding these ERM surgeries.

METHODS AND DESIGN

This is a prospective, multicenter cohort study of ERM surgery in Japan from March 1, 2023, to March 31, 2027 (UMIN000048472, R-3468-2). Patients who underwent ERM surgery during the study period and agreed to participate in this study will be included. The goal is to have a total of 5,000 eyes surgically treated for ERM. The following data will be collected: age, gender, medical history, subjective symptoms, visual function before and 6 and 12 months after surgery, clinical findings, OCT data, surgical technique, instruments used in surgery, and complications.

DISCUSSION

The results of this study will support the surgical decisions and procedures in ERM practices.

Long-Term Visual Outcomes in Patients With Idiopathic Epiretinal Membrane Surgery

BACKGROUND AND OBJECTIVE

Our aim was to assess long-term outcomes following surgical repair of idiopathic epiretinal membrane (ERM) with pars plana vitrectomy (PPV) and membrane peel (MP).

PATIENTS AND METHODS

A retrospective study evaluated patients with idiopathic ERM who underwent surgical repair at a single academic tertiary center with five to nine years of postoperative follow-up, assessing preoperative characteristics, surgical techniques, best visual acuity (BVA), and optical coherence tomography biomarkers at various time points.

RESULTS

The study involved 67 patients (72 eyes) with an average postoperative follow-up of 82.8 ± 18.8 months. Patients with cone outer segment tips integrity at initial presentation and 1-year follow-up and patients with external limiting membrane and ellipsoid zone integrity at 1-year follow-up were noted to have significantly better long-term visual acuity than those without. More than 85% of patients achieved a BVA > 70 seven years after surgical repair.

CONCLUSIONS

Vitreoretinal surgery for idiopathic ERM resulted in improved anatomical recovery and sustained visual acuity gain over long-term follow-up. [Ophthalmic Surg Lasers Imaging Retina 2024;55:70-77.].

Inhibition of Rho kinase (ROCK) impairs cytoskeletal contractility in human Müller glial cells without effects on cell viability, migration, and extracellular matrix production

The epiretinal membrane is a fibrocontractile tissue that forms on the inner surface of the retina, causing visual impairment ranging from mild to severe, and even retinal detachment. Müller glial cells actively participate in the formation of this membrane. Current research is constantly seeking for new therapeutic approaches that aim to prevent or treat cellular dysfunctions involved in the progression of this common fibrosis condition. The Rho GTPases signaling pathway regulates several processes associated with the epiretinal membrane, such as cell proliferation, migration, and contraction. Rho kinase (ROCK), an effector of the RhoA GTPase, is an interesting potential therapeutic target. This study aimed to evaluate the effects of a ROCK inhibitor (Y27632) on human Müller cells viability, growth, cytoskeletal organization, expression of extracellular matrix components, myofibroblast differentiation, migration, and contractility. Müller cells of the MIO-M1 lineage were cultured and treated for different periods with the inhibitor. Viability was evaluated by MTT assay and trypan blue exclusion method, and growth was evaluated by growth curve and BrdU incorporation assay. The actin cytoskeleton was stained with fluorescent phalloidin, intermediate filaments and microtubules were analyzed with immunofluorescence for vimentin and α-tubulin. Gene and protein expression of collagens I and V, laminin and fibronectin were evaluated by rt-PCR and immunofluorescence. Chemotactic and spontaneous cell migration were studied by transwell assay and time-lapse observation of live cells, respectively. Cell contractility was assessed by collagen gel contraction assay. The results showed that ROCK inhibition by Y27632 did not affect cell viability, but decreased cell growth and proliferation after 72 h. There was a change in cell morphology and organization of F-actin, with a reduction in the cell body, disappearance of stress fibers and formation of long, branched cell extensions. Microtubules and vimentin filaments were also affected, possibly because of F-actin alterations. The inhibitor also reduced gene expression and immunoreactivity of smooth muscle α-actin, a marker of myofibroblasts. The expression of extracellular matrix components was not affected by the inhibitor. Chemotactic cell migration showed no significant changes, while cell contractility was substantially reduced. No spontaneous migration of MIO-M1 cells was observed. In conclusion, pharmacological inhibition of ROCK in Müller cells could be a potentially promising approach to treat epiretinal membranes by preventing cell proliferation, contractility and transdifferentiation, without affecting cell viability.

Clinical features of idiopathic epiretinal membrane in children and the factors influencing postoperative visual acuity

PURPOSE

To describe the characteristics and surgical outcomes of idiopathic epiretinal membrane (iERM) in children and to determine the factors associated with postoperative visual acuity (VA).

METHODS

We retrospectively reviewed the medical records of 17 patients with iERM (age, < 18 years) who had undergone ERM surgery from 2009 to 2021. Spectral-domain optical coherence tomography features were documented. The eyes with iERMs involving the fovea were assigned to the localized and diffused groups depending on the morphological description of the membrane. Multiple linear regression analysis was used to explore the factors associated with the final VA.

RESULTS

The mean age was 9.2 ± 3.8 years. The mean follow-up period was 38.9 ± 45.4 months. After surgery, the central foveal thickness and the best-corrected VA (BCVA) improved significantly (all, P < 0.05). Fourteen eyes with iERMs showed involvement of the foveal area (localized group, six eyes; diffused group, eight eyes). There were no significant differences in the preoperative BCVA between the two groups (P = 0.064). However, the final BCVA was better in the diffused group than in the localized group (P = 0.043). Multiple regression analysis indicated that the localized membrane (P = 0.042) and lower preoperative BCVA (P = 0.043) were factors associated with a worse final VA in pediatric iERMs.

CONCLUSIONS

Surgical removal of ERM showed a high anatomical and functional success rate in children. In pediatric patients with iERMs involving the fovea, a good VA was more common when the membrane was diffused than when it was localized.

Binocular visual function improvement after pars plana vitrectomy for epiretinal membrane

PURPOSE

To report binocular visual function changes after pars plana vitrectomy for epiretinal membrane (ERM) and the related outcomes.

METHODS

Twenty-three eyes of 23 patients operated on for ERM were included in a retrospective study. Clinical data, best-corrected visual acuity (BCVA), contrast sensitivity and binocular visual function were assessed pre- and 1 and 3 months post-operatively. Binocular visual function assessment included the evaluation of fusional amplitudes (i.e., vergences) by the synoptophore, far distance stereopsis using polarized glasses and near stereopsis using Randot and TNO tests. Central macular thickness (CMT) was measured on Spectral Domain - Optical Coherence Tomography.

RESULTS

Mean age of the patients was 67 years. Mean BCVA and contrast sensitivity significantly improved post-operatively at one (p = 0.0006 and p = 0.0022, respectively) and 3 months (p < 0.0001 and p < 0.0001, respectively), while CMT significantly decreased after 1-3 months (p < 0.0001 and p < 0.0001, respectively). Fusional amplitudes improved after 3 months (p < 0.0001). Far distance and near stereopsis significantly improved after 3 months (p < 0.0001 and p = 0.0007 for Randot test, and p < 0.0001 for TNO test, respectively).

CONCLUSIONS

Pars plana vitrectomy for ERM surgery leads to an improvement of monocular and binocular visual functions (i.e., binocular fusion, near and far distance stereopsis), within 3 months post-operatively.

Effect of Air Tamponade among Patients with Epiretinal Membranes and Intraretinal Cystoid Changes Undergoing Vitrectomy with Membrane Peeling - A Prospective Randomized Trial

BACKGROUND

The effect of air tamponade among patients undergoing vitrectomy with membrane peeling for removal of epiretinal membranes (ERM) is controversially discussed. The aim of the present study was to analyze differences in outcomes between air tamponade and balanced salt solution (BSS) in a study population with preoperative intraretinal cystoid changes.

PATIENTS AND METHODS

This randomized study included patients scheduled for pars plana vitrectomy with membrane peeling owing to ERM and intraretinal cystoid changes. Air tamponade or BSS at the end of surgery was applied according to preoperative randomization. Optical coherence tomography and best-corrected distance visual acuity (DCVA) measurements were performed before surgery, 5 days after surgery, and 3 months after surgery.

RESULTS

From 96 patients included, 85 eyes had full follow-up and could be included for analysis. Median improvement of DCVA was + 16 EDTRS letters (IQR: 8 to 22) among patients with BSS, while it was + 13 EDTRS letters (IQR: 8 to 17) among patients with air tamponade. There was a trend for better improvement of DCVA when BSS was left at the end of surgery, compared to air tamponade, but not reaching statistical significance.

CONCLUSIONS

There were no statistically significant differences concerning resorption of preoperative intraretinal cystoid changes, improvement of visual acuity, and final DVCA between air tamponade and BSS.

Diagnostic Reliability of Optical Coherence Tomography Biomarkers for Postsurgical Success in Visual Acuity in Patients with Idiopathic Epiretinal Membranes

INTRODUCTION

Several optical coherence tomography (OCT) biomarkers for postsurgical success in patients with idiopathic epiretinal membranes (iERMs) have been described in single predictor analyses. The aim of this study was to assess the reliability of diagnosis of OCT biomarkers and to calculate their impact on postsurgical visual acuity by applying multiple regression analysis.

METHODS

This retrospective study included patients scheduled for pars plana vitrectomy with membrane peeling for iERMs. Presurgical OCT scans were analyzed for the presence of OCT biomarkers by two reviewers. Intra- and interobserver reliability was calculated with the Kuder-Richardson 20 test.

RESULTS

Among the 136 patients included, intra-/interobserver reliability of the OCT biomarkers was 0.89/0.70 for ectopic inner foveal layer (EIFL), 0.82/0.53 for disorganization of retinal inner layer (DRIL), 0.93/0.89 for intraretinal cystoid changes, 0.84/0.78 for alterations of the ellipsoid zone, 0.84/0.72 for cotton ball sign, 0.68/0.58 for hyperreflective foci, 0.55/0.47 for epimacular membrane rips (EMM-rips), and 0.87/0.60 for retinal contraction. Only DRIL and central subfield macular thickness (CMT) were significant predictors for BCVA 3 months after surgery in a multiple regression analysis.

CONCLUSION

Intraobserver reliability of OCT biomarkers was higher than interobserver reliability, reflecting both clinical and grading experience with respect to OCT biomarker evaluation. DRIL and CMT were shown to be significant predictors in a multiple regression analysis, with potential for negative influence on final BCVA after vitrectomy with membrane peeling for iERMs.

Short-term-outcomes of idiopathic epiretinal membranes treated with pars-plana-vitrectomy - examination of visual function and OCT-morphology

BACKGROUND

Epiretinal membranes (ERM) represent one of the most common findings in retinal examination. Structural changes of the retinal layers in patients with ERM can be visualized and classified using OCT. The purpose of this study is to evaluate structural and functional changes related to surgical treatment of ERM.

METHODS

Monocentric retrospective analysis of 92 patients who underwent 23-gauge-pars plana vitrectomy (ppV) combined with cataract surgery for idiopathic ERM from 2015 to 2020. Visual acuity was determined directly preoperatively, at four weeks and three months postoperatively. Disease stage and tomographic biomarkers related to ERM were assessed in OCT imaging.

RESULTS

92 eyes of 92 patients were included. At the time of surgery, the mean patient age was 71 years. Visual acuity improved significantly by 2 lines postoperatively, on average from LogMar 0.4 to 0.2 (p < 0.001). Disease stage regressed from stage 3 to stage 2 postoperatively (p < 0.001). No patient had stage 4 postoperatively (n = 0). In the presence of preoperative intraretinal fluid, mean retinal thickness was 488 μm and decreased to 392 μm postoperatively (n = 32; p < 0.001). Preoperative presence of a Cotton Ball Sign (n = 30) was associated with better visual acuity (p = 0.009). This was also visible in patients with preoperative vitreomacular traction syndrome (p < 0.001). The presence of preoperative intraretinal fluid showed a tendency towards better disease staging after surgery (p = 0.080).

CONCLUSION

Surgery was able to achieve visual improvement and morphological regression of the preoperative OCT findings related to ERM. ppV led to a reduction in retinal thickness and disease stage. The presence of the Cotton Ball Sign and vitreomacular traction was associated with better visual acuity in the follow-up period. In our cohort the preoperative presence of intraretinal fluid showed a tendency for better postoperative disease staging.

Epiretinal Membrane Impairs the Inner Retinal Layer in a Traction Force-Dependent Manner

Purpose

To investigate the relationship between retinal traction force and impairment of the inner retinal layer in patients with epiretinal membrane (ERM).

Design

Nonrandomized, retrospective consecutive case series.

Participants

Two hundred nine eyes of 201 patients with idiopathic ERM who underwent vitrectomy for idiopathic ERM were enrolled.

Methods

Retinal folds caused by ERM were visualized using en face OCT, and the maximum depth of retinal folds within the parafovea (MDRF) was measured. Focal macular electroretinogram (ERG) was used to measure the amplitude and implicit time of each component for the ERM eyes and the normal fellow eyes. B-scan OCT images were used to measure the thicknesses of the inner nuclear layer (INL) and outer nuclear layer (ONL) + outer plexiform layer (OPL). Expression of α-smooth muscle actin (α-SMA) in surgically removed ERM specimens was quantified by reverse-transcription polymerase chain reaction.

Main Outcome Measures

We analyzed the relationship between MDRF and the relative amplitudes of focal macular ERG (affected eye/fellow eye), the relationships between MDRF and the mean INL thickness and ONL+OPL thickness, comparison of INL thickness and ONL+OPL thickness for each area when cases were classified according to MDRF localization in the ETDRS chart, and the relationship between MDRF and the relative expression of α-SMA in the ERM specimens.

Results

The MDRF significantly correlated with the relative amplitudes (affected eye/fellow eye) of b-waves and oscillatory potentials (r = -0.657, P = 0.015; r = -0.569, P = 0.042, respectively) and the mean INL thickness and ONL+OPL thickness (r = 0.604, P < 0.001; r = 0.210, P = 0.007, respectively). However, only the INL thickness progression rate was significantly correlated with the MDRF progression rate (r = 0.770, P < 0.001). On case stratification by localization of MDRF based on the ETDRS chart, in regions other than temporal regions, the INL thickness was significantly greater in regions with MDRF than in other regions. The MDRF significantly correlated with α-SMA expression in the ERM specimens (r = 0.555, P = 0.009).

Conclusions

The findings suggest that ERM impairs the inner retinal layer in a traction force-dependent manner.

Financial Disclosures

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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.

Investigating the associations of macular edema in retinitis pigmentosa

Macular edema (ME), the accumulation of intraretinal fluid in the macula, is a common sight affecting sequelae of retinitis pigmentosa (RP). However, it is unclear why some patients develop ME, and others do not. This study aims to identify associations between clinical-genetic factors in RP with ME. Patients with clinically confirmed RP cases were identified from the inherited retinal disease database at a large tertiary referral academic center. Demographic and genetic testing findings were noted. Additionally, optical coherence tomography volume scans were graded using a validated grading system. One hundred and six patients (73.1%) were found to have ME in at least one eye (OD = 88, mean = 37.9%, OS = 98, mean = 31.7%). Structurally, the presence of epiretinal membrane (ERM) (p < 0.007) and vitreo-macular traction (VMT) (p < 0.003) were significantly associated with ME. Additionally, X-linked (p < 0.032) and autosomal dominant inheritance (p < 0.039) demonstrated a significant association with ME, with RP1 (p < 0.045) and EYS (p < 0.017) pathogenic variants also significantly associated with ME. This study, in a large cohort of RP patients, confirms previous retinal structural associations for ME in RP and identifies potential new genetic associations.

EVALUATION OF VISION-RELATED QUALITY OF LIFE IN PATIENTS AFTER VITRECTOMY FOLLOWING IDIOPATHIC EPIRETINAL MEMBRANE

PURPOSE

To evaluate the impact of different intraocular tamponades on the vision-related quality of life (VRQOL) after idiopathic epiretinal membrane (IEM) surgery with epiretinal membrane peeling.

METHODS

We prospectively enrolled 50 patients diagnosed with IEM who underwent pars plana vitrectomy. Patients were consecutively assigned to either the air tamponade (air) group (25 patients) or the balanced salt solution (BSS) tamponade group (25 patients). The following data were collected before and after surgery and compared between the two groups: VRQOL, best-corrected visual acuity, intraocular pressure, metamorphopsia, contrast sensitivity, and central macular thickness.

RESULTS

Pars plana vitrectomy was performed in 50 eyes. At baseline, there were no significant differences between the two groups. At 6 months postoperatively, VRQOL ( P < 0.001), best-corrected visual acuity ( P < 0.001), central macular thickness ( P < 0.001), contrast sensitivity ( P < 0.001), and metamorphopsia ( P < 0.001) improved significantly in comparison with baseline, without significant differences between the air tamponade and BSS groups.

CONCLUSION

Removing IEM significantly improved visual function and VRQOL. Despite improvements, this study showed no difference postoperatively whether air or BSS tamponade was used during surgery. As a result, air tamponade may not be a mandatory treatment for IEM surgery and provides no additional advantage compared with BSS tamponade.

TOPOGRAPHIC ASSESSMENT OF INTRARETINAL CYSTOID SPACE AND ITS PROGNOSTIC VALUES IN IDIOPATHIC EPIRETINAL MEMBRANE

PURPOSE

To assess the topographical distribution of intraretinal cystoid space (IRC) and its prognostic value in idiopathic epiretinal membrane (iERM).

METHODS

One hundred twenty-two eyes of iERM that had been followed up for 6 months after membrane removal were included. Based on the baseline IRC distribution, the eyes were divided into Groups A, B, and C (absence, IRC within 3 mm, and 6 mm from the fovea, respectively). The best-corrected visual acuity (BCVA), central subfield macular thickness (CSMT), ectopic inner foveal layer, and microvascular leakage (ML) were assessed.

RESULTS

Fifty-six eyes (45.9%) had IRC, of which 35 (28.7%) were in Group B and 21 (17.2%) in Group C at baseline. Compared with group B, group C showed worse BCVA, thicker CSMT, and a greater association with ML (OR = 5.415; P = 0.005) at baseline; and also presented with worse BCVA, thicker CSMT, and wider distribution of IRC postoperatively. A wide distribution of IRC was an unfavorable baseline factor in achieving good visual acuity (OR = 2.989; P = 0.031).

CONCLUSION

Widely distributed IRCs were associated with advanced disease phenotype as poor BCVA, thick macula, and baseline ML in iERM and also showed a poor visual outcome after membrane removal.

Microperimetric evaluation for different methods of epiretinal membrane surgery

PURPOSE

To investigate the anatomic and functional outcomes using microperimetry for the surgical methods for idiopathic epiretinal membranes (ERM).

METHODS

This retrospective study included 41 eyes from 41 patients. All patients underwent combined epiretinal membrane and cataract surgery. Best-corrected visual acuity (BCVA), optical coherence tomography, and microperimetry were performed before and 6 months and 1 year after surgery. The patients were divided into 3 groups; "ERM removal only without indocyanine green (ICG) staining", "ERM and internal limiting membrane (ILM) removal without ICG staining", and "ERM and ILM removal with ICG staining".

RESULTS

Preoperatively, the ages, BCVAs, central macular thickness (CMT), and mean retinal sensitivities of central 6° (MRSs) of the groups were not significantly different (p > 0.05). Postoperatively, the MRSs of the "ERM removal only without ICG staining" and "ERM and ILM removal without ICG staining" groups were not significantly different (p > 0.05). The MRSs of the "ERM and ILM removal without ICG staining" and "ERM and ILM removal with ICG staining" groups were not significantly different (p > 0.05). However, the MRSs of the "ERM and ILM removal with ICG staining" group significantly reduced than "ERM removal only without ICG staining" group (p < 0.05).

CONCLUSION

This retrospective study found reduced retinal sensitivity in ERM and ILM removal with ICG staining group compared to ERM removal only without ICG staining. Further studies with larger sample sizes are required.

Comparison of the morphological characteristics of the choroidal sublayer between idiopathic macular holes and epiretinal membranes with automatic analysis

PURPOSE

To compare the choroidal sublayer morphologic features between idiopathic macular hole (IMH) and idiopathic epiretinal membrane (iERM) on spectral-domain optical coherent tomography (SD-OCT) using an automatic segmentation model.

METHODS

Thirty-three patients with idiopathic IMHs and 44 with iERMs who underwent vitrectomies were involved. The enhanced depth imaging mode of SD-OCT was used to obtain the B-scan image after single line scanning of the macular fovea. The choroidal sublayer automatic analysis model divides the choroidal into the choroidal large vessel layer, the middle vessel layer and the small vessel layer (LVCL, MVCL and SVCL, respectively) and calculates the choroidal thickness (overall, LVCL, MVCL and SVCL) and vascular index (overall, LVCL, MVCL and SVCL). The morphological characteristics of the choroidal sublayer in the ERM eyes and the IMH eyes were compared.

RESULTS

The mean choroidal thickness in the macular centre of the IMH eyes was significantly thinner than that of the ERM eyes (206.35 ± 81.72 vs. 273.33 ± 82.31 μm; P < 0.001). The analysis of the choroidal sublayer showed that the MVCL and SVCL macular centres and 0.5-1.5 mm of the nasal and temporal macula were significantly thinner in the IMH eyes than in the ERM eyes (P < 0.05), and there was a difference in the macular centre of the LVCL between the two groups (P < 0.05). In contrast, the choroidal vascular index of the macular centre in the IMH eyes was significantly higher than that in iERM eyes (0.2480 ± 0.0536 vs. 0.2120 ± 0.0616; P < 0.05). There was no significant difference in the CVI of other parts of the macula, the LVCL or MVCL between the two groups.

CONCLUSION

The choroidal thickness of the IMH eyes was significantly thinner than that of the iERM eyes, which was mainly observed in 3 mm of the macular centre and the MVCL and SVCL layers of the choroid. The choroidal vascular index of the IMH eyes was higher than that of the iERM eyes. These findings suggest that the choroid may be involved in the pathogenesis of IMH and iERM.

Pars Plana Vitrectomy in Inherited Retinal Diseases: A Comprehensive Review of the Literature

Inherited retinal diseases (IRDs) are a group of clinically and genetically heterogeneous disorders that may be complicated by several vitreoretinal conditions requiring a surgical approach. Pars plana vitrectomy (PPV) stands as a valuable treatment option in these cases, but its application in eyes with such severely impaired chorioretinal architectures remains controversial. Furthermore, the spreading of gene therapy and the increasing use of retinal prostheses will end up in a marked increase in demand for PPV surgery for IRD patients. The retinal degeneration that typically affects patients with hereditary retinal disorders may influence the execution of the surgery and the expected results. Considering the importance of PPV application in IRD-related complications, it is fundamental to try to understand from the literature what is adequate and safe in posterior eye segment surgery. Use of dyes, light toxicity, and risk of wounding scar development have always been themes that discourage the execution of vitreoretinal surgery in already impaired eyes. Therefore, this review aims to comprehensively summarize all PPV applications in different IRDs, highlighting the favorable results as well as the potential precautions to consider when performing vitreoretinal surgery in these eyes.

Associations between macular retinal vasculature and severity of idiopathic epiretinal membrane

BACKGROUND

To demonstrate the associations between the morphology of macular retinal vasculature and disease severity of idiopathic epiretinal membrane (ERM).

METHODS

Macular structures were assessed using optical coherence tomography (OCT), and were classified as "with pseudohole" or "without pseudohole". The 3 × 3 mm macular OCT angiography images were analyzed using the Fiji software to obtain the vessel density, skeleton density, average vessel diameter, vessel tortuosity, fractal dimension, and foveal avascular zone (FAZ)-related parameters. The correlations between these parameters and ERM grading as well as visual acuity were analyzed.

RESULTS

For ERM with or without a pseudohole, increased average vessel diameter, decreased skeleton density, and decreased vessel tortuosity were all associated with inner retinal folding and thickened inner nuclear layer, indicating more severe ERM. In 191 eyes without a pseudohole, the average vessel diameter increased, fractal dimension decreased and vessel tortuosity decreased with increasing ERM severity. The FAZ was not associated with ERM severity. Decreased skeleton density (r = -0.37), vessel tortuosity (r = -0.35), and increased average vessel diameter (r = 0.42) were correlated with worse visual acuity (All P < 0.001). In 58 eyes with pseudoholes, a larger FAZ was associated with a smaller average vessel diameter (r = -0.43, P = 0.015), higher skeleton density (r = 0.49, P < 0.001), and vessel tortuosity (r = 0.32, P = 0.015). However, none of the retinal vasculature parameters correlated with visual acuity and central foveal thickness.

CONCLUSION

Increased average vessel diameter, decreased skeleton density, decreased fractal dimension and decreased vessel tortuosity were good indicators of ERM severity and associated visual impairment.

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.

Comparisons of Handheld Retinal Imaging with Optical Coherence Tomography for the Identification of Macular Pathology in Patients with Diabetes

INTRODUCTION

Handheld retinal imaging cameras are relatively inexpensive and highly portable devices that have the potential to significantly expand diabetic retinopathy (DR) screening, allowing a much broader population to be evaluated. However, it is essential to evaluate if these devices can accurately identify vision-threatening macular diseases if DR screening programs will rely on these instruments. Thus, the purpose of this study was to evaluate the detection of diabetic macular pathology using monoscopic macula-centered images using mydriatic handheld retinal imaging compared with spectral domain optical coherence tomography (SDOCT).

METHODS

Mydriatic 40°-60° macula-centered images taken with 3 handheld retinal imaging devices (Aurora [AU], SmartScope [SS], RetinaVue 700 [RV]) were compared with the Cirrus 6000 SDOCT taken during the same visit. Images were evaluated for the presence of diabetic macular edema (DME) on monoscopic fundus photographs adapted from Early Treatment Diabetic Retinopathy Study (ETDRS) definitions (no DME, noncenter-involved DME [non-ciDME], and center-involved DME [ciDME]). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each device with SDOCT as gold standard.

RESULTS

Severity by ETDRS photos: no DR 33.3%, mild NPDR 20.4%, moderate 14.2%, severe 11.6%, proliferative 20.4%, and ungradable for DR 0%; no DME 83.1%, non-ciDME 4.9%, ciDME 12.0%, and ungradable for DME 0%. Gradable images by SDOCT (N = 217, 96.4%) showed no DME in 75.6%, non-ciDME in 9.8%, and ciDME in 11.1%. The ungradable rate for images (poor visualization in >50% of the macula) was AU: 0.9%, SS: 4.4%, and RV: 6.2%. For DME, sensitivity and specificity were similar across devices (0.5-0.64, 0.93-0.97). For nondiabetic macular pathology (ERM, pigment epithelial detachment, traction retinal detachment) across all devices, sensitivity was low to moderate (0.2-0.5) but highly specific (0.93-1.00).

CONCLUSIONS

Compared to SDOCT, handheld macular imaging attained high specificity but low sensitivity in identifying macular pathology. This suggests the importance of SDOCT evaluation for patients suspected to have DME on fundus photography, leading to more appropriate referral refinement.

MicroRNA-494 augments fibrotic transformation of human retinal pigment epithelial cells and targets p27 with cell-type specificity

Epiretinal membranes (ERMs) are the result of fibro-cellular proliferation that cause distortion and impairment of central vision. We hypothesized that select microRNAs (miRs) regulate retinal fibro-proliferation and ERM formation. Following IRB approval, a pilot study was performed in patients presenting for retina surgery with and without clinical ERMs. Total RNA was isolated from ERM tissue and controls from non-ERM vitreous and subjected to miR profiling via microarray analysis. MiR-494 was identified as the only miR selectively expressed at significantly greater levels, and in silico analysis identified p27 as a putative fibroproliferative gene target of miR-494. In vitro testing of miR-494 and p27 in fibrotic transformation was assessed in spontaneously immortalized human retinal pigment epithelial (RPE) and human Müller cell lines, stimulated to transform into a fibroproliferative state via transforming growth factor beta (TGFβ). Fibroproliferative transformation was characterized by de novo cellular expression of alpha smooth muscle actin (αSMA). In both RPE and Müller cells, both TGFβ and miR-494 mimic decreased p27 expression. In parallel experiments, transfection with p27 siRNA augmented TGFβ-induced αSMA expression, while only in RPE cells did co-transfection with miR-494 inhibitor decrease αSMA levels. These results demonstrate that miR-494 augments fibrotic transformation in both Müller cells and RPEs, however only in RPEs does miR-494 mediate fibrotic transformation via p27. As p27 is known to regulate cellular proliferation and differentiation, future studies should extend clinical testing of miR-494 and/or p27 as a potential novel non-surgical therapy for ERMs, as well as identify relevant miR-494 targets in Müller cells.

Combined versus Sequential Pars Plana Vitrectomy and Phacoemulsification for Macular Hole and Epiretinal Membrane - A Systematic Review and Meta-Analysis

TOPIC

To compare the efficacy and safety between combined and sequential pars plana vitrectomy and phacoemulsification for macular hole (MH) and epiretinal membrane (ERM).

CLINICAL RELEVANCE

The standard of care for MH and ERM is vitrectomy, which increases risk of developing cataract. Combined phacovitrectomy eliminates the need for a second surgery.

METHODS

Ovid MEDLINE, EMBASE, and Cochrane CENTRAL were searched in May 2022 for all articles comparing combined versus sequential phacovitrectomy for MH and/or ERM. The primary outcome was mean best-corrected visual acuity (BCVA) at 12-months follow-up. Meta-analysis was conducted using a random effects model. Risk of bias was assessed using the Cochrane RoB 2 tool for randomized controlled trials (RCTs) and ROBINS-I tool for observational studies. (PROSPERO, registration number, CRD42021257452) RESULTS: Of the 6470 studies found, 2 RCTs and 8 non-randomized retrospective comparative studies were identified. Total eyes for combined and sequential groups were 435 and 420, respectively. Meta-analysis suggested no significant difference between combined and sequential surgery for 12-month BCVA (combined = 0.38 logMAR, sequential = 0.36 logMAR; mean difference (MD) = +0.02 logMAR; 95% CI = -0.04 to 0.08; p = 0.51, I² = 0%, n = 4 studies, 398 participants), as well as absolute refractive error (p = 0.76, I² = 97%, n = 4 studies, 289 participants), risk of myopia (p = 0.15, I² = 66%, n = 2 studies, 148 participants), MH non-closure (p = 0.57, I² = 48%, n = 4 studies, 321 participants), cystoid macular edema (p = 0.15, I² = 0%, n = 6 studies, 526 participants), high intraocular pressure (p = 0.09, I² = 0%, n = 2 studies, 161 participants), posterior capsule opacification (p = 0.46, I² = 0%, n = 2 studies, 161 participants), posterior capsule rupture (p = 0.41, I² = 0%, n = 5 studies, 455 participants) and retinal detachment (p = 0.67, I² = 0%, n = 6 studies, 545 participants).

CONCLUSION

No significant difference was detected between combined and sequential surgeries for visual outcomes, refractive outcomes, or complications. Given that most studies were retrospective and contained a high risk-of-bias, future high-quality RCTs are warranted.

Total and horizontal distances of the foveal stereotaxic displacement can be prognostic indicators for patients with idiopathic epiretinal membrane

Introduction

This study aimed to examine the foveal stereo deviations in the different ectopic inner foveal layer (EIFL) stages of idiopathic epiretinal membrane (iERM) and assess its predictive utility for the baseline and postoperative best-corrected visual acuity (BCVA).

Methods

Based on the calculational combination of foveal displacements in the horizontal and vertical axial optical coherence tomography (OCT) images, the foveal stereotaxic displacement was estimated through the total distance (TD, the distance from the foveal bottom to the inner edge of displaced central foveal) and horizontal distance (HD, projection of the TD in the retinal plane). The preoperative TD, HD, and other OCT- and OCT angiography (OCTA)-related indicators were obtained. The correlations between structural parameters and baseline and postoperative BCVA were evaluated through correlation and multiple linear regression analyses.

Results

In patients with advanced EIFL stage, there was a significant increase in the HD, TD, baseline log of the minimum angle of resolution unit for BCVA, central macular thickness (CMT), acircularity index, and incidence of microcystic macular edema (MME; p &lt; 0.05). Further, they showed a decreased foveal avascular zone (FAZ) area and perimeter (p &lt; 0.001). HD, TD, CMT, MME, FAZ area, and FAZ perimeter were significantly correlated with the baseline and postoperative BCVA (p &lt; 0.05). TD had the highest correlation indexic and was an individual predictor of the baseline and postoperative BCVA. Moreover, FD-300 and MME were individual predictors of postoperative BCVA.

Discussion

Stereoscopic foveal deviations significantly correlated with the baseline and postoperative visual acuity. TD may be used as an independent prognostic factor for BCVA.

The G-Protein-Coupled Formyl Peptide Receptor 2 Promotes Endothelial-Mesenchymal Transition in Diabetic Retinopathy

INTRODUCTION

In proliferative diabetic retinopathy (PDR), retinal neovascularization is the essential pathogenic process that is linked to endothelial-to-mesenchymal transition (EndoMT) induced by high glucose (HG). This pathophysiological process may be regulated by a G-protein-coupled chemoattractant receptor FPR2 (mouse Fpr2), involved in inflammatory cell migration and proliferation. In the current study, we investigated the role of Fpr2 in regulating EndoMT and the underlying mechanisms during diabetic retinopathy progression.

METHODS

FPR2 agonist or inhibitor was added to human microvascular endothelial cells (HMECs) exposed to normal glucose or HG. Morphologic, phenotypic, and functional changes of HMECs as well as the formation of microvasculature related to EndoMT were assessed. EndoMT biomarkers were detected in the retinal tissues of diabetic mice and fibrovascular epiretinal membranes (FVMs) from patients with PDR.

RESULTS

HG upregulated FPR2 in HMECs, which triggered morphological changes, and the cells acquired mesenchymal phenotype, with enhanced cell migration, viability, and angiogenic process shown by tube formation and aortic ring sprouting. Inhibition of FPR2 attenuated HG-induced EndoMT and endothelial cell migration to form vessel-like tube structures. RNA sequence and protein analysis further revealed that inhibition of FPR2 decreased the expression of genes associated with EndoMT. ERK1/2 and P38 signaling pathway was activated in HMECs, promoting neovascularization in HG-induced EndoMT of HMECs. In vivo, increased expression of mesenchymal markers was detected in the retina of diabetic mice and FVMs from patients with PDR. FPR2 deficiency was associated with diminished EndoMT-related phenotypic changes in the retina of diabetic mice.

CONCLUSIONS

FPR2 is actively involved in the progression of EndoMT that may contribute to the pathogenesis of PDR. Thus, FPR2 may be a potential therapeutic target for PDR.

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.

Quantitative cone contrast threshold testing in patients with differing pathophysiological mechanisms causing retinal diseases

BACKGROUND

Cone contrast threshold testing (CCT) provides quantitative measurements of color and contrast function to reveal changes in vision quality that are not standard endpoints in clinical trials. We utilize CCT to measure visual function in patients with multiple sclerosis (MS), age-related macular degeneration (AMD), epiretinal membrane (ERM), and retinal vein occlusion (RVO).

METHODS

Retrospective data was gathered from 237 patients of the Gavin Herbert Eye Institute. Subjects included 17 patients with MS, 45 patients with AMD, 41 patients with ERM, 11 patients with RVO, and 123 healthy controls. Patients underwent the primary measurement outcome, CCT testing, as well as Sloan visual acuity test and spectral domain optical coherence tomography during normal care.

RESULTS

Color and contrast deficits were present in MS patients regardless of history of optic neuritis. AMD with intermediate or worse disease demonstrated reduced CCT scores. All 3 stages of ERM demonstrated cone contrast deficits. Despite restoration of visual acuity, RVO-affected eyes demonstrated poorer CCT performance than unaffected fellow eyes.

CONCLUSIONS

CCT demonstrates color and contrast deficits for multiple retinal diseases with differing pathophysiology. Further prospective studies of CCT in other disease states and with larger samples sizes is warranted.

NEW ARTIFICIAL INTELLIGENCE ANALYSIS FOR PREDICTION OF LONG-TERM VISUAL IMPROVEMENT AFTER EPIRETINAL MEMBRANE SURGERY

PURPOSE

To predict improvement of best-corrected visual acuity (BCVA) 1 year after pars plana vitrectomy for epiretinal membrane (ERM) using artificial intelligence methods on optical coherence tomography B-scan images.

METHODS

Four hundred and eleven (411) patients with Stage II ERM were divided in a group improvement (IM) (≥15 ETDRS letters of VA recovery) and a group no improvement (N-IM) (<15 letters) according to 1-year VA improvement after 25-G pars plana vitrectomy with internal limiting membrane peeling. Primary outcome was the creation of a deep learning classifier (DLC) based on optical coherence tomography B-scan images for prediction. Secondary outcome was assessment of the influence of various clinical and imaging predictors on BCVA improvement. Inception-ResNet-V2 was trained using standard augmentation techniques. Testing was performed on an external data set. For secondary outcome, B-scan acquisitions were analyzed by graders both before and after fibrillary change processing enhancement.

RESULTS

The overall performance of the DLC showed a sensitivity of 87.3% and a specificity of 86.2%. Regression analysis showed a difference in preoperative images prevalence of ectopic inner foveal layer, foveal detachment, ellipsoid zone interruption, cotton wool sign, unprocessed fibrillary changes (odds ratio = 2.75 [confidence interval: 2.49-2.96]), and processed fibrillary changes (odds ratio = 5.42 [confidence interval: 4.81-6.08]), whereas preoperative BCVA and central macular thickness did not differ between groups.

CONCLUSION

The DLC showed high performances in predicting 1-year visual outcome in ERM surgery patients. Fibrillary changes should also be considered as relevant predictors.

Evaluation of the optical coherence tomography findings of patients with idiopathic epiretinal membrane

BACKGROUND

This study aimed to determine the relationship between basal visual acuity (VA) and basal optical coherence tomography (OCT) parameters of patients with idiopathic epiretinal membrane (iERM).

METHODS

The study included 200 eyes of 200 patients with iERM. In the evaluation of basal VAs, logMAR 0.3 (0.5 on Snellen chart) was accepted as the limit, and the patients were divided into two groups as Group 1 with VA values below logMAR 0.3 and Group 2 with those above logMAR 0.3. Using OCT, the ellipsoid zone (EZ), interdigitation zone (IZ), external limiting membrane (ELM) integrity, peaked appearance of EZ in the fovea, disorganization of the inner retinal layers (DRIL), central foveal thickness (CFT), maximum retinal thickness (MRT), total photoreceptor length (TPL), photoreceptor outer segment length (PROSL), photoreceptor deformity index (PDI), and inner retinal layer irregularity index (IRLII) were evaluated and compared between the groups.

RESULTS

There were an equal number of patients in Group 1 and Group 2. The preservation of ELM, EZ, and IZ integrity and the peaked appearance of EZ in the fovea were observed at higher rates in Group 1, whereas the rate of DRIL was higher in Group 2 (p < 0.05 for all). In the multiple regression analysis performed to evaluate categorical OCT parameters, only the presence of DRIL was found to be significantly associated with VA (p < 0.003). CFT*, MRT*, and IRLII** were significantly lower in Group 1 (*p < 0.001, **p = 0.001). TPU, PROSL, and FDI were similar between the two groups (p > 0.05 for all).

CONCLUSION

According to the multiple regression analysis, only the presence of DRIL was correlated with lower VA values. Among the OCT parameters, an increase in CFT and MRT, as well as the IRLII value moving away from 1 were related to lower VA values.

Prediction of Visual Impairment in Epiretinal Membrane and Feature Analysis: A Deep Learning Approach Using Optical Coherence Tomography

PURPOSE

The aim was to develop a deep learning model for predicting the extent of visual impairment in epiretinal membrane (ERM) using optical coherence tomography (OCT) images, and to analyze the associated features.

METHODS

Six hundred macular OCT images from eyes with ERM and no visually significant media opacity or other retinal diseases were obtained. Those with best-corrected visual acuity ≤20/50 were classified as "profound visual impairment," while those with best-corrected visual acuity >20/50 were classified as "less visual impairment." Ninety percent of images were used as the training data set and 10% were used for testing. Two convolutional neural network models (ResNet-50 and ResNet-18) were adopted for training. The t-distributed stochastic neighbor-embedding approach was used to compare their performances. The Grad-CAM technique was used in the heat map generative phase for feature analysis.

RESULTS

During the model development, the training accuracy was 100% in both convolutional neural network models, while the testing accuracy was 70% and 80% for ResNet-18 and ResNet-50, respectively. The t-distributed stochastic neighbor-embedding approach found that the deeper structure (ResNet-50) had better discrimination on OCT characteristics for visual impairment than the shallower structure (ResNet-18). The heat maps indicated that the key features for visual impairment were located mostly in the inner retinal layers of the fovea and parafoveal regions.

CONCLUSIONS

Deep learning algorithms could assess the extent of visual impairment from OCT images in patients with ERM. Changes in inner retinal layers were found to have a greater impact on visual acuity than the outer retinal changes.

Longitudinal Change of Choroidal Thickness after Pars Plana Vitrectomy for Idiopathic Epiretinal Membrane

This study aimed to investigate changes in choroidal thickness after pars plana vitrectomy (PPV) with and without air tamponade in patients with idiopathic epiretinal membrane (ERM). We retrospectively reviewed 61 patients with ERM who underwent a 25-gauge transconjunctival sutureless PPV. The patients were divided into two groups: the air tamponade group (30 eyes) and the nontamponade group (31 eyes). Subfoveal choroidal thickness (SFCT) was analyzed over 12 months. No significant differences were seen between the two groups at baseline. For all patients, the SFCT was significantly thicker at 1 month after surgery and significantly thinner at 6 and 12 months after surgery than preoperative values. In the subgroup analysis, there was no significant difference in SFCT 3 months after surgery compared with the preoperative values in both groups, but SFCT was significantly lower 6 months after surgery in both groups. In conclusion, our results showed that choroidal thickness temporarily increased after surgery and then gradually decreased until 12 months after the PPV for ERM.

Natural History and Surgical Timing for Idiopathic Epiretinal Membrane

PURPOSE

This study assessed the prevalence of progression to surgery on idiopathic epiretinal membrane (iERM) and compared the results with those of immediate surgery.

DESIGN

Retrospective study with nested case-control comparison.

SUBJECTS

Patients with mild iERM at initial presentation METHODS: A retrospective study with a nested case-control study was conducted to compare the outcomes of those who later progressed to surgery ("deferred surgery") with those of a control group that underwent surgery within 6 months of initial presentation ("immediate surgery").

MAIN OUTCOME MEASURES

The prevalence of performing vitrectomy with membrane peeling after initial deferral, features associated with deferred surgery, and the visual acuity (VA) outcomes of surgery compared with those with immediate surgery.

RESULTS

A total of 413 patients were included in the base study cohort: 369 did not undergo iERM peeling, whereas 44 (10.7%) underwent deferred surgery at a mean duration of 18.1 months after initial presentation. The factor most associated with later progression to surgery, determined using a multivariate analysis, was symptoms at initial presentation (odds ratio [95% confidence interval], 8.75 [3.80-20.15]; P < 0.0001). The immediate surgical group (controls) had a poorer logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) at presentation compared with the deferred surgery group (cases), but this decreased in the latter group to about the same preoperative level immediately before the deferred surgery (typically why they underwent surgery). The final logMAR BCVA was similar in the deferred and immediate surgical groups when only pseudophakic cases were analyzed. An analysis of the change from preoperative BCVA (instead of initial) to final BCVA showed no difference in the magnitude of change between the pseudophakic subgroups of the deferred and immediate surgery groups (median [interquartile range] preoperative VA of 0.52 [0.40-0.60] in the deferred surgery group and 0.44 [0.39-0.60] in the immediate surgery group [P = 0.7256]). Within the deferred and immediate surgery groups, the median change from preoperative BCVA to final BCVA in the pseudophakic subgroups was 0.22 (P = 0.0082) in the former and 0.21 (P = 0.0001) in the latter.

CONCLUSIONS

The vast majority of eyes with iERM remain stable after initial presentation. The deferral of surgery in the minority of patients who progress does not have a disadvantageous final outcome compared with immediate surgery.

The Diagnostic Value of Neutrophil to Lymphocyte Ratio as an Effective Biomarker for Eye Disorders: A Meta-Analysis

The neutrophil to lymphocyte ratio (NLR) reflects a dynamic relationship between the innate (neutrophils) and adaptive (lymphocytes) cellular immune response. This systematic review and meta-analysis was conducted to critically evaluate the literature regarding the use of the NLR as a reliable means to detect several ocular disorders. Our study was registered with the PROSPERO (ID: CRD42022314850). Three databases, including PubMed, Embase, Scopus, and the Web of Science, were searched on September 9, 2022, with no restrictions on the article's language. Finally, 32 articles were recognized as eligible for our meta-analysis. We found that patients with eye diseases had significantly elevated levels of NLR in comparison to healthy controls (SMD =0.53, 95% CI =0.35-0.71, P < 0.001). In subgroup analysis, patients with keratoconus (SMD =0.69; 95% CI =0.33-1.05, P < 0.001), glaucoma (SMD =0.56, 95% CI =0.25-0.87, P < 0.001), pterygium (SMD =0.14; 95% CI =0.01-0.26, P < 0.001), and idiopathic epiretinal membrane (SMD =0.14; 95% CI =0.01-0.26, P < 0.001) had higher levels of NLR compared to healthy controls. However, NLR levels of patients with dry eye disease were similar to healthy controls (SMD =0.32, 95% CI = -0.49-1.13, P = 0.435). It can be said that NLR is a valuable marker of systemic inflammation, which is significantly increased in many eye disorders, suggesting that inflammation plays a key role in the pathophysiology of these diseases.

SURGICAL OUTCOMES OF VASOPROLIFERATIVE RETINAL TUMORS' REFRACTORY TO NONINVASIVE THERAPIES

PURPOSE

To evaluate the outcomes of surgical treatment of refractory vasoproliferative retinal tumors (VPTs) and its complications.

METHODS

Clinical charts of all patients diagnosed with VPTs who underwent surgical treatment from 2005 to 2020 were reviewed. Clinical features, surgical techniques, and outcomes were evaluated.

RESULTS

From 25 eyes of 23 patients with VPTs, 17 (68%) eyes underwent surgical intervention to treat tumor activity and associated complications including epiretinal membrane (n = 10, 59%), retinal detachment (n = 8, 47%), and vitreous hemorrhage (n = 3, 18%). All eyes underwent pars plana vitrectomy with endolaser/cryotherapy to control tumor activity and to treat associated complications. Three cases required tumor resection. At the end of follow-up (mean 55.4 months, range 2-305 months), no eye presented tumor activity or retinal detachment after one or two surgeries. There was no epiretinal membrane recurrence. The mean baseline best-corrected visual acuity was 1.2 ± 0.7 logMAR, and the mean final best-corrected visual acuity was 0.7 ± 0.6 logMAR ( P < 0.05). The best-corrected visual acuity improved two or more lines in 12 (70.5%) eyes at the end of follow-up.

CONCLUSION

In this series of patients with large active VPTs, surgical intervention allowed control of the tumor activity in all patients and provided overall satisfactory anatomic and functional outcomes.

DEEP LEARNING-BASED PREDICTION OF OUTCOMES FOLLOWING NONCOMPLICATED EPIRETINAL MEMBRANE SURGERY

PURPOSE

We used deep learning to predict the final central foveal thickness (CFT), changes in CFT, final best corrected visual acuity, and best corrected visual acuity changes following noncomplicated idiopathic epiretinal membrane surgery.

METHODS

Data of patients who underwent noncomplicated epiretinal membrane surgery at Severance Hospital from January 1, 2010, to December 31, 2018, were reviewed. Patient age, sex, hypertension and diabetes statuses, and preoperative optical coherence tomography scans were noted. For image analysis and model development, a pre-trained VGG16 was adopted. The mean absolute error and coefficient of determination (R 2 ) were used to evaluate the model performances. The study involved 688 eyes of 657 patients.

RESULTS

For final CFT, the mean absolute error was the lowest in the model that considered only clinical and demographic characteristics; the highest accuracy was achieved by the model that considered all clinical and surgical information. For CFT changes, models utilizing clinical and surgical information showed the best performance. However, our best model failed to predict the final best corrected visual acuity and best corrected visual acuity changes.

CONCLUSION

A deep learning model predicted the final CFT and CFT changes in patients 1 year after epiretinal membrane surgery. Central foveal thickness prediction showed the best results when demographic factors, comorbid diseases, and surgical techniques were considered.

Incidence and risk factors of progressive nasal inner nuclear layer thickening after surgical peeling of epiretinal membrane

To assess incidence and risk factors of postoperative progressive nasal inner nuclear layer (INL) thickening after epiretinal membrane (ERM) surgery. Progressive nasal INL thickening was defined as 1.5-fold increase in thickness of nasal INL after ERM surgery compared to preoperative examination. Kaplan–Meier survival analysis was done to compare the cumulative risk ratio between groups stratified by presence of progressive nasal INL thickening. Logistic regression was performed to identify possible risk factors. Progressive nasal INL thickening occurred in 13.0% of ERM removal patients. Patients without progressive nasal INL thickening showed better visual acuity recovery compared to patients with nasal INL thickening (p = 0.029). Presence of cystoid space in inner retinal layer before surgery (odds ratio [OR] = 0.143, 95% confidence interval [CI] 0.028–0.736; p = 0.020), older age (OR = 0.896, 95% CI 0.817–0.982, p = 0.020), and thicker preoperative central macular thickness (OR = 0.994, 95% CI 0.988–1.000, p = 0.039) were correlated inversely with thickening of nasal INL. Correlation between nasal INL thickness and postoperative visual outcome was significant. Absence of cystoid space before ERM surgery, younger age, and thinner central macular thickness were risk factors for progressive postoperative nasal INL thickening. Progressive nasal INL thickening may serve as a new biomarker for worsened visual symptom after ERM surgery.