Insights Into Epiretinal Membranes: Presence of Ectopic Inner Foveal Layers and a New Optical Coherence Tomography Staging Scheme

MICROVASCULAR LEAKAGE IS A POOR PROGNOSTIC FACTOR FOR IDIOPATHIC EPIRETINAL MEMBRANE: A Fluorescein Angiography Study

PURPOSE

To investigate the angiographic findings assessed using fluorescein angiography and their prognostic values of idiopathic epiretinal membrane.

METHODS

Seventy-three eyes of idiopathic epiretinal membrane that had been followed up for 6 months after surgical treatment were included. Midphase fluorescein angiography images were obtained at baseline. Structural changes, including central subfield macular thickness, intraretinal cystic lesion, and ectopic inner retinal layer on the fovea, were assessed using optical coherence tomography. The main outcome measures were microvascular leakage (ML) and its association with optical coherence tomography findings and best-corrected visual acuity (BCVA).

RESULTS

Of a total of 73 eyes, 37 showed ML and had worse BCVA (P = 0.040), greater central subfield macular thickness (P = 0.028), and more ectopic inner retinal layer (P < 0.001) than those without ML at baseline. Also, ML was associated with worse postoperative BCVA (P < 0.001) and ectopic inner retinal layers (P < 0.001; P = 0.034) at baseline and 6 months. The baseline factors associated with postoperative BCVA of ≥20/25 were better BCVA (P = 0.027) and the absence of ML (P < 0.001).

CONCLUSION

Half of the idiopathic epiretinal membrane eyes showed that ML was associated with inner retinal deformity and poor visual recovery. Fluorescein angiography helped to predict visual prognosis after idiopathic epiretinal membrane surgery.

EPIRETINAL MEMBRANE SURGERY IN PATIENTS WITH MULTIFOCAL VERSUS MONOFOCAL INTRAOCULAR LENSES

PURPOSE

To compare the visual/anatomical outcomes and feasibility of epiretinal membrane surgery between patients with multifocal or monofocal intraocular lenses (IOLs).

METHODS

We reviewed the medical records of 46 patients who underwent epiretinal membrane surgery under multifocal or monofocal IOL pseudophakia. The operation time, mean changes in best-corrected visual acuity, and central macular thickness, and complications were compared between the groups.

RESULTS

Macular surgery was performed in 22 and 24 eyes with multifocal and monofocal IOLs, respectively. The total operation time and the total membrane peeling time were similar in both groups (P = 0.125, P = 0.462, respectively). The mean time to create a membrane edge or flap with retinal microforceps was longer for multifocal than for monofocal IOLs (P = 0.013). The mean changes in best-corrected visual acuity and central macular thickness were similar in both groups (P = 0.682, P = 0.741, respectively). Complications were similar between groups.

CONCLUSION

With multifocal IOLs, vision outside the central surgical field was blurred, requiring more time to create the membrane flap. Retinal surgeons should anticipate the difficulty in precise focusing when creating a membrane flap in macular surgery in patients with multifocal IOLs and should pay more attention to the macular surgery.

Impact of Epiretinal Membrane on Optical Coherence Tomography Tools Used for Monitoring Glaucoma

Background: Retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) measurements can be influenced by many factors including the presence of concomitant retinal diseases. The aim of this study it to assess the impact of epiretinal membrane (ERM) on RNFL and GCL assessment using optical coherence tomography (OCT). Methods: GCL, peripapillary RNFL (pRNFL), and Bruch’s Membrane Opening Minimum Rim Width (BMO-MRW) thicknesses were analysed using an SD-OCT (Spectralis OCT) in eyes with idiopathic ERM and compared with a control group. Results: 161 eyes were included, 73 eyes in the control group and 88 eyes with idiopathic ERM. The pRNFL analysis revealed a statistically significant difference between the two groups in overall and temporal sector thicknesses. For GCL thickness report, the percentage of scans in which the GCL was erroneously segmented by automatic segmentation was assessed for each eye. A statistically significant difference was found in all sectors (p < 0.001), with the exception of external nasal sector. A statistically significant difference (p < 0.001) in the GCL total volume report was found in ERM group compared to the control group. For MRW at BMO analysis, there was no statistically significant difference in MRW thickness in any sector. Conclusion: In eyes with ERM, the GCL and pRNFL analysis seemed affected by the morphological retinal layers’ modification. MRW-BMO did not appear to be directly affected by the presence of ERM.

Epiretinal proliferation after rhegmatogenous retinal detachment

PURPOSE

To determine the characteristics and appearance rate of epiretinal proliferation (ERP) on SD-OCT after surgery for rhegmatogenous retinal detachment (RRD) repair.

METHODS

One hundred eight eyes of 108 patients who underwent one or more surgeries for RRD were enrolled. The eyes with other maculopathies that were directly related to RRD were excluded. Image acquisition was performed with SD-OCT (Heidelberg Engineering, Germany). Clinical charts were reviewed to assess clinical and surgical findings. Statistical analyses were performed using XLSTAT (Assinsoft, Paris, France).

RESULTS

ERP was found in 9.3% eyes (n = 10). The mean initial visual acuity (logMAR) was 1.34 ± 0.82 in the ERP group compared to 0.49 ± 0.70 in the non-ERP group. PVR was present in 70.0% and chronic macular edema was found in 80.0% of eyes which developed ERP. The mean number of vitreoretinal surgeries in eyes with ERP was 3.3 ± 1.19 and only 1.44 ± 1.02 in eyes without. Silicone oil was used in 60.0% of eyes which developed ERP compared to 13.9% in the non-ERP group.

CONCLUSION

ERP is a late-onset postoperative finding in eyes with RRD and can occur in absence of macular holes. Overall, ERP is more frequent in eyes with complicated courses of RRD including multiple operations, PVR, usage of silicone oil, and chronic macular edema.

Effect of Foveal Pit Restoration in Foveal Avascular Zone After Surgery for idiopathic Epiretinal Membrane

Purpose

To investigate the relationship between ophthalmic parameters—including optical coherence tomography (OCT) and OCT angiography findings—and foveal pit restoration in eyes that had undergone vitrectomy for idiopathic epiretinal membrane (iERM) removal.

Methods

This study retrospectively analyzed data of patients who underwent pars planar vitrectomy for the removal of epirentinal membrane. Only eyes with iERM above stage 2 with a follow-up over 6 months were included. Baseline data and changes in ophthalmic parameters were analyzed from 3 months before to 12 months after surgery. Additionally, we stratified iERM patients into two groups (foveal pit restoration and no restoration group). Longitudinal comparison analyses between the two groups were done in best-corrected visual acuity (BCVA), central foveal thickness (CFT) and foveal avascular zone (FAZ) areas measurements using swept-source OCT and OCT angiography.

Results

Forty-three patients with a mean age of 75 ± 5 years were enrolled. After surgery, BCVA, FAZ, and CFT showed improvements over time (all p < 0.002). Thirty-one patients were designated into the foveal pit restoration (R) group and 12 patients into the no restoration (NR) group. Differences in BCVA and FAZ area in both groups existed up to 6 months. However, BCVA improved and FAZ expanded (R, 0.20 ± 0.05 vs. NR, 0.18 ± 0.04) in both groups showing no statistical difference 12 months postsurgery. The CFT decreased in both groups, but the R group was thinner at every point compared to the NR group (all p < 0.05).

Conclusions

The removal of epirentinal membrane in pars planar vitrectomy significantly improves BCVA, decreases the CFT and expands the FAZ. Foveal pit restoration improves BCVA, CFT, and FAZ area possibly at a faster rate in the early months but long-term improvements could be achieved regardless of the status of foveal pit restoration.

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.

Assessment of macular microvasculature features before and after vitrectomy in the idiopathic macular epiretinal membrane using a grading system: An optical coherence tomography angiography study

PURPOSE

To evaluate pre- and postoperative microvasculature features in eyes with different idiopathic macular epiretinal membrane (iERM) classifications using optical coherence tomography angiography (OCTA).

METHODS

In this retrospective study, 100 eyes with iERM were enrolled; 62 eyes underwent pars plana vitrectomy (PPV). All iERM eyes were evaluated and graded using optical coherence tomography (OCT). According to the thickness of the fovea relative to the surrounding macula from OCT radial line scans, we classified iERM into three grades. Optical coherence tomography angiography (OCTA) was used to measure the foveal avascular zone (FAZ)-related parameters and the superficial and deep capillary plexus layers using 3 × 3 mm scans. Measurements were taken at baseline and 3 months postoperatively. Best corrected visual acuity (BCVA), vessel density (VD), FAZ area, FAZ perimeter (PERIM), acircularity index (AI), and foveal vessel density (FD) were evaluated.

RESULTS

Idiopathic macular epiretinal membrane (iERM) eyes with a higher grade had a lower FAZ area and perimeter (p < 0.0001), higher foveal vessel density (FVD) both in the superficial capillary plexus (SCP) (p < 0.0001) and in the deep capillary plexus (DCP) (p < 0.05), and a lower parafoveal vessel density (PRVD) in the DCP (p < 0.0001). The macular vessel density ratio (MVR = FVD/PRVD) increased with an increase in grade both in the SCP and in the DCP (p < 0.0001). For grade 1 iERM eyes, only PRVD in the DCP significantly changed before versus after the operation (p < 0.05). For grade 2 iERM eyes, the FAZ area and perimeter became larger after the operation (p < 0.05). The MVR of grade 2 iERM eyes decreased postoperatively both in the SCP (p < 0.05) and in the DCP (p < 0.001). For grade 1 and grade 2 iERM eyes, preoperative LogMAR BCVA was negatively correlated with the FAZ area (p < 0.01) and perimeter (p < 0.01), and was positively correlated with the MVR in the SCP (p < 0.05). Postoperative LogMAR BCVA was positively correlated with the FVD in the DCP (p < 0.05).

CONCLUSIONS

Idiopathic macular epiretinal membrane (iERM) eyes of different grades have significant differences in microvasculature features. According to OCTA, eyes with higher grades have more serious microvascular changes. Grading plays a part in predicting postoperative microvascular characteristics, and grade 1 iERM eyes have a better visual outcome compared with grade 2 iERM eyes.

FOVEAL DISPLACEMENT IN EYES WITH EPIRETINAL MEMBRANE AFTER VITRECTOMY AND MEMBRANE PEELING

PURPOSE

To investigate the foveal movement in eyes with epiretinal membrane after vitrectomy and membrane peeling.

METHODS

A retrospective review of 85 eyes with epiretinal membrane treated with vitrectomy, membrane peeling, and internal limiting membrane removal. Using a self-designed computer program to compare the preoperative and postoperative images of optical coherence tomography to measure the amount of foveal movement. Analyze the relationships between foveal displacement, preoperative and postoperative best-corrected visual acuity, central foveal thickness, and the stage of epiretinal membrane.

RESULTS

Most of the fovea were nasally shifted. More movement happened in the first month and almost finished in the first year. The greater degree of foveal displacement was correlated with poorer initial visual acuity and thicker central foveal thickness. In considering with the ectopic inner foveal layer staging of epiretinal membrane by structural optical coherence tomography, the foveal realignment is greatest in Stage 4 (394.47 ± 171.44 µm), followed by Stage 1 (251.21 ± 135.40 µm), Stage 2 (235.70 ± 147.51 µm), and Stage 3 (219.86 ± 117.91 µm) at the postoperative 1 month.

CONCLUSION

Most eyes of epiretinal membrane had the foveal moved nasally after membrane peeling and internal limiting membrane peeling. The larger amount of foveal movement was correlated with poorer initial best-corrected visual acuity. Dystopia fovea may be another factor affecting visual acuity in addition to other biomarkers in optical coherence tomography.

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.

Optical coherence tomography analysis of surgical outcomes of combined hamartoma of retina and retinal pigment epithelium

PURPOSE

To evaluate the surgical outcomes in combined hamartoma of retina and retinal pigment epithelium (CHRRPE) using optical coherence tomography (OCT).

METHODS

This was a retrospective interventional study, in which medical records of 12 eyes with CHRRPE that underwent vitrectomy and membrane peeling at three tertiary vitreoretinal institutes were reviewed. Preoperative and postoperative color fundus photographs and OCT were reviewed for each follow-up visit.

RESULTS

Five out of 12 eyes had a good visual outcome (equal or more than 2 lines gain in visual acuity), four had stable visual outcome (<2 line gain), and three had poor visual outcome (loss of visual acuity). Preretinal fibrosis preoperatively was seen in 80% of cases with good outcomes as compared to 50% and 0% of cases in the cohorts with stable and poor outcomes, respectively. Preoperatively all 5 cases with good visual outcome had Grade 4 epiretinal membrane (ERM), while only 1 case with stable and poor visual outcome had grade 4 ERM and the rest had Grade 3 ERM. Maxi peaks were seen in 80%, 50%, and 0% of cases preoperatively in the three cohorts, respectively. Hyperreflectivity of inner retinal layers preoperatively was evident in all cases having good visual outcomes, in 75% of cases with stable visual outcomes, and in 33% of cases with poor outcomes.

CONCLUSION

Surgical intervention in CHRRPE with preretinal fibrosis seems to be beneficial. The visual recovery as defined by conventional predictors in cases of surgical removal of ERM fails to explain the visual outcome in CHRRPE.

Risk factors for macular pucker after rhegmatogenous retinal detachment surgery

Macular pucker, also known as an epiretinal membrane, sometimes forms after surgical repair of a rhegmatogenous retinal detachment (RRD) and can decrease visual acuity and cause aniseikonia. However, few reports are evaluating the risk factors of macular pucker using multivariate analysis. To evaluate the risk factors for macular pucker after RRD surgery, 226 patients who underwent RRD surgery and were monitored for greater than 12 months (23.2 ± 6.4 months) after surgery were analyzed retrospectively. Of these cases, macular pucker developed in 26 cases. Multiple logistic regression models of 22 clinical characteristics were performed. An increased risk of macular pucker after RRD surgery was significantly associated with preoperative vitreous haemorrhage (Odds ratio (OR), 4.71; 95% CI 1.19–18.62), multiple retinal breaks (OR, 8.07; 95% CI 2.35–27.71), re-detachment (OR, 19.66; 95% CI 4.87–79.38), and retinal detachment area (OR, 12.91; 95% CI 2.34–71.19). Macular pucker was not associated with the surgical technique. Regardless of the surgical technique used, careful observation for postoperative macular pucker is needed after RRD surgery in high-risk cases. These findings can be used to improve the surgical management of patients with RRD. (183 words).

The Postoperative Course of Choroidal and Central Retinal Thickness in Epiretinal Membranes with Respect to Membrane Severity

INTRODUCTION

The aim of this study was to evaluate the relation between choroidal thickness (CT), central retinal thickness (CRT) and best-corrected visual acuity (BCVA) after surgery for idiopathic epiretinal membrane (iERM).

METHODS

Patients with 4 severity stages of iERM, who underwent vitrectomy with membrane- and internal limiting membrane peeling, were included in this prospective study. CRT, CT, and BCVA were assessed at baseline (BSL), 1 week, 1 and 3 months postoperatively.

RESULTS

Twenty-one eyes were phakic, 11 eyes pseudophakic at BSL, in 14 cases combined cataract surgery was performed. BCVA was highest in stage 1 and 2, lowest in stage 4 iERM (p < 0.001) and correlated with CRT. After surgery, CRT decreased and BCVA increased significantly (p < 0.05). CT did not show significant differences among stages (p = 0.23). BSL CRT did not differ between phakic and pseudophakic eyes, the least reduction after surgery was detected in patients who underwent combined cataract surgery and vitrectomy. BSL CT was greater in phakic than in pseudophakic eyes (p = 0.033). Postoperative CT decreased in pseudophakic and phakic eyes, but remained higher after combined surgery (p = 0.0048).

CONCLUSION

CT is not related to the severity of iERM. Choroidal changes did not influence the BCVA. Additional cataract surgery seems to cause longer recovery in CT and CRT.

TEMPORAL CHANGES OF PARAFOVEAL MICROVASCULATURE AFTER EPIRETINAL MEMBRANE SURGERY: An Optical Coherence Tomography Angiography Study

PURPOSE

To investigate whether the parafoveal capillary architecture predicts clinical course and visual outcomes after epiretinal membrane (ERM) surgery.

METHODS

A total of 71 eyes of 71 patients treated with vitrectomy for idiopathic ERM were enrolled. The parafoveal capillary displacement and fractal geometries were compared according to the stage of ERM. Correlations between the parafoveal capillary displacement in the superficial capillary plexus, the fractal dimension and lacunarity in the deep capillary plexus (DCP), foveal thickness, and visual outcomes were evaluated.

RESULTS

Compared with eyes with mild ERM, eyes with severe ERM exhibited higher parafoveal capillary displacement in the superficial capillary plexus, lower fractal dimension and higher lacunarity in the DCP, and greater foveal thickness (P < 0.05). The parafoveal capillary displacement in the superficial capillary plexus and fractal dimension and lacunarity in the DCP improved significantly, particularly at 1 month postoperatively (P < 0.05) and reached a plateau thereafter. The preoperative fractal dimension in the DCP showed a significant correlation with the best-corrected visual acuity at all follow-up time points (P < 0.05).

CONCLUSION

The parafoveal fractal dimension in the DCP was significantly correlated with the visual acuity before and after ERM surgery. The parafoveal fractal dimension may serve as a predictive marker for visual outcomes after ERM surgery.

Is pseudoexfoliation syndrome associated with vitreoretinal interface abnormalities?

BACKGROUND

To evaluate vitreoretinal interface abnormalities in patients with pseudoexfoliation (PEX) syndrome.

METHODS

This case-control study was performed in 136 patients diagnosed with unilateral PEX (PEX group) and 139 age- and sex-matched healthy volunteers (Control group). Both the affected and contralateral eyes were evaluated in the PEX group and the right eye was evaluated in the Control group. Vitreoretinal interface abnormalities and posterior vitreous detachment (PVD) were evaluated on optical coherence tomography (OCT) examination.

RESULTS

The incidences of incomplete and complete PVD were significantly higher in the affected than contralateral eye in the PEX group and in the right eye in the Control group (P = 0.009, P = 0.012 and P = 0.004, P = 0.017, respectively). The rates of 'no PVD' were significantly higher in the contralateral eye in the PEX group and the Control group compared to the affected eye in the PEX group (P = 0.003 and P = 0.001, respectively). The odds ratio for incomplete PVD was 3.1 in PEX eyes compared to the contralateral eye in the PEX group and 3.9 compared to the Control group. The rate of epiretinal membranes (ERMs) in the affected eye was significantly different from the contralateral eye in the PEX and Control groups (P < 0.001 and P < 0.001, respectively). The odds ratio for ERM in PEX eyes was 3.51 compared to the contralateral eye in the PEX group and 4.23 compared to the Control group. In the presence of incomplete PVD, the odds ratio for ERM development was 3.81 in PEX eyes.

CONCLUSIONS

We detected high rates of ERMs and incomplete PVD in patients with PEX. It is important to evaluate and follow up PEX cases in terms of vitreoretinal interface abnormalities.

Incidence and Risk Factors of Epiretinal Membrane after Cataract Surgery

Purpose: To investigate the incidence and risk factors of epiretinal membrane (ERM) after cataract surgery.Methods: We reviewed the medical records of patients who underwent cataract surgery between January 2016 and December 2018. Eyes with ERM, as observed by optical coherence tomography performed 1-2 months after surgery, were excluded from the study. ERM was diagnosed by fundus photography. The incidence rate was determined 2-6, 6-12, and 12-24 months after surgery. The cumulative incidence rate of ERM was calculated by Kaplan-Meier analysis. Data were analyzed using logistic regression to determine the associations between ERM development and various factors.Results: The study included 218 eyes of 161 patients with a mean age of 66.6 ± 9.7 years at the time of surgery. ERM was observed in 3 of 218 eyes (1.4%) between 2 and 6 months, 15 of 176 eyes (8.3%) between 6 and 12 months, and 14 of 150 eyes (10.3%) between 12 and 24 months after surgery. The cumulative incidence rate of ERM was 11.7% over the 24-month period after surgery. In multivariate logistic regression analysis, older age (≥65 years; odds ratio [OR], 8.59, 95% confidence interval [CI], 1.43-51.49), fellow eye with ERM (OR, 3.63; 95% CI, 1.04-12.73), longer axial length (≥26 mm; OR, 8.02; 95% CI, 1.08-59.66), and complete posterior vitreous detachment development (OR, 7.48; 95% CI, 1.64-34.14) were significantly associated with ERM development.Conclusions: ERM is not rare after cataract surgery. Long-term retinal examination should be required after cataract surgery.

Increased risk of postsurgical macular edema in high stage idiopathic epiretinal membranes

PURPOSE

To assess the rate of occurrence and the risk factors of postsurgical macular edema (PSME) in eyes with idiopathic epiretinal membrane (iERM) or full-thickness macular hole (FTMH).

METHODS

Retrospective longitudinal analysis of all subjects scheduled for vitrectomy with or without combined cataract surgery over a 6-month period. Electronic medical charts and imaging data were analyzed preoperatively and at 1, 3 and 6 months after surgery.

RESULTS

From 101 patients diagnosed with iERM or FTMH, 71 patients were eligible for the study. Forty-nine eyes with iERM (69.0%) and 22 eyes with FTMH (31.0%) underwent vitrectomy either isolated (31.0%) or combined with cataract extraction (69.0%). The overall rate of PSME was 26.7%, without differences between the two groups (P = 0.9479). Combined cataract extraction did not affect the overall occurrence of PSME rate in both groups (P = 0.9255 in FTMH and P = 0.8658 in iERM). If grouped by stage, eyes with stage 4 iERM though disclosed an increased rate of PSME (57.1%) compared to lower (1 to 3) stages (14.3%, P = 0.0021), particularly when combined with cataract surgery (71.4% vs. 15.4% in stages ≤ 3, P = 0.0021). The PSME odds ratio for a stage 4 iERM is 8 (95% CI: 1.933-33.1; P = 0.0041) compared to stages 3 and below.

CONCLUSIONS

PSME remains a clinically relevant and frequent event after surgery for iERM and FTMH. Patients with stage 4 iERM have an 8-fold higher likelihood of developing PSME in a 6-month postsurgical period compared to iERM in 1-3 stages, especially when combined with cataract extraction.

RETINAL SURFACE WRINKLING AS AN INDICATOR FOR INTERNAL LIMITING MEMBRANE PEELING DURING VITRECTOMY FOR RETINAL DETACHMENT

PURPOSE

To assess the validity of retinal surface wrinkling (RSW) as an indicator to select patients relevant for internal limiting membrane peeling during vitrectomy for rhegmatogenous retinal detachment, to prevent postoperative visual decline due to epiretinal membrane growth.

METHODS

This was a prospective, interventional case series of 78 consecutive eyes that underwent initial vitrectomy to repair rhegmatogenous retinal detachments and were followed for 6 months. The presence/absence of RSW was evaluated presurgically on en face optical coherence tomographic images. The internal limiting membrane was peeled if RSW was identified. The main outcome measure was the prevalence of postsurgical epiretinal membrane growth that caused a visual decline of 0.2 or more in logarithm of the minimum angle of resolution unit.

RESULTS

The internal limiting membrane was peeled for RSW appearance in 22 eyes (28.2%). Mild epiretinal membranes developed in 8 of the 56 internal limiting membrane-unpeeled eyes (10.3% of total, 6 eyes at stage 1 in the classification of Govetto); however, visual decline occurred in none of them with the mean visual acuity of these 8 eyes maintained at -0.08 ± 0.11 in logarithm of the minimum angle of resolution (≈20/16).

CONCLUSION

Visual decline due to epiretinal membrane growth after rhegmatogenous retinal detachment repair was entirely prevented by peeling the internal limiting membrane in about 30% of cases selected for the presence of RSW.

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.

Inner retinal structure and visual function after idiopathic epiretinal membrane surgery with and without brilliant blue G

PURPOSE

Vital dyes are frequently used to visualize the internal limiting membrane (ILM) of the neuroretina. This study evaluated and compared the microstructure of the inner retina and visual function with and without brilliant blue G (BBG) staining for ILM peeling during idiopathic epiretinal membrane (ERM) surgery.

STUDY DESIGN

Retrospective, consecutive, interventional case series.

METHODS

Fifty-five patients (55 eyes) with ERM underwent ILM peeling without dyes (non-dye group) and 55 patients (55 eyes) underwent ILM peeling with BBG staining (BBG group). The logMAR visual acuity (VA) and ganglion cell complex (GCC) thickness were measured using optical coherence tomography at baseline and 12 months after surgery.

RESULTS

LogMAR VA improved significantly in both groups at 12 months and the BBG group tended to be better than the non-dye group but with no significant difference between the groups (unpaired t-test, P = 0.490). The average GCC thickness significantly decreased in both groups; however, there was no difference in the rates of change in GCC thickness between the groups. The ratio of GCC thickness to total retinal thickness (%) was significantly higher in the BBG group in the superior quadrant at 12 months postoperatively (P = 0.010).

CONCLUSION

BBG-assisted ERM surgery resulted in better visual improvement and fewer structural changes in the inner retinal layers. BBG-assisted ILM peeling is safe both functionally and anatomically.

Agreement of optical coherence tomography thickness measurements between Heidelberg Eye Explorer and ImageJ software

OBJECTIVE

To investigate the agreement and correlation of manual central foveal thickness (CFT) measurements using the Heidelberg Eye Explorer and ImageJ software.

METHODS

Optical coherence tomography (OCT) images were identified. CFT was measured using the Heidelberg Eye Explorer caliper tool. Two independent graders measured the CFT of the same images using ImageJ software. A Pearson correlation coefficient, intraclass correlation coefficient, Bland-Altman plots, and coefficient of repeatability were used to assess the agreement and correlation between the Heidelberg Eye Explorer and ImageJ measurements.

RESULTS

One-hundred and twenty-two OCT images from 91 patients were analyzed. Mean CFT as measured using the Heidelberg caliper tool was 264.8 ± 113 µm. Using ImageJ software, graders 1 and 2 obtained mean CFT values of 267 ± 114.3 µm and 270 ± 114.8 µm, respectively. Pearson correlation revealed a strong correlation between the Heidelberg and Image J measurements (r = 0.999, p < 0.0001). Bland-Altman plots noted a less than 4 µm mean difference between Heidelberg and ImageJ CFT values (2.67 ± 3.46 and 3.72 ± 2.78 µm for graders 1 and 2, respectively).

CONCLUSION

There was strong agreement between the Heidelberg Eye Explorer and ImageJ software for manual CFT measurements. ImageJ may be a reliable tool for thickness measurements when proprietary OCT software is unavailable.

Evaluation of postoperative visual function based on the preoperative inner layer structure in the epiretinal membrane

PURPOSE

To evaluate the postoperative visual function using a preoperative epiretinal membrane (ERM) classification based on the status of the inner layer structure.

METHODS

We assessed 62 eyes, one from each patient undergoing vitrectomy with internal limiting membrane (ILM) peeling for unilateral ERM. The inclusion criteria were as follows: (1) the presence of idiopathic ERM based on optical coherence tomography and a healthy contralateral eye, (2) successful surgery after 25- or 27-gauge transconjunctival 3-port pars plana vitrectomy with ILM peeling, and (3) a minimum follow-up period of 12 months. We included patients with preoperative ERM morphology with no disruption of the inner retinal layer in group A (37 eyes) and those with disruption in group B (25 eyes) and compared the visual acuity, central visual-field sensitivity (CVFS) measured using the Humphrey field analyzer 10-2 program, and detection rate of micro-scotoma (< 10 dB) at baseline and 12 months postoperatively between the groups.

RESULTS

Visual acuity at 12 months showed greater improvement in group A than in group B (P = .03). There was no significant difference in CVFS at baseline; however, that of the nasal area was substantially lower after surgery in group B than in group A (P = .02). The 12-month postoperative detection rate of micro-scotoma was significantly higher in group B than in group A (P = .002).

CONCLUSION

ERM that has preoperatively disrupted the inner layer poses the risks of CVFS reduction and micro-scotoma formation after vitrectomy. Evaluating the inner layer could be an important prognostic factor in determining retinal function in ERM.

Müller cells and astrocytes in tractional macular disorders

Tractional deformations of the fovea mainly arise from an anomalous posterior vitreous detachment and contraction of epiretinal membranes, and also occur in eyes with cystoid macular edema or high myopia. Traction to the fovea may cause partial- and full-thickness macular defects. Partial-thickness defects are foveal pseudocysts, macular pseudoholes, and tractional, degenerative, and outer lamellar holes. The morphology of the foveal defects can be partly explained by the shape of Müller cells and the location of tissue layer interfaces of low mechanical stability. Because Müller cells and astrocytes provide the structural scaffold of the fovea, they are active players in mediating tractional alterations of the fovea, in protecting the fovea from such alterations, and in the regeneration of the foveal structure. Tractional and degenerative lamellar holes are characterized by a disruption of the Müller cell cone in the foveola. After detachment or disruption of the cone, Müller cells of the foveal walls support the structural stability of the foveal center. After tractional elevation of the inner layers of the foveal walls, possibly resulting in foveoschisis, Müller cells transmit tractional forces from the inner to the outer retina leading to central photoreceptor layer defects and a detachment of the neuroretina from the retinal pigment epithelium. This mechanism plays a role in the widening of outer lameller and full-thickness macular holes, and contributes to visual impairment in eyes with macular disorders caused by conractile epiretinal membranes. Müller cells of the foveal walls may seal holes in the outer fovea and mediate the regeneration of the fovea after closure of full-thickness holes. The latter is mediated by the formation of temporary glial scars whereas persistent glial scars impede regular foveal regeneration. Further research is required to improve our understanding of the roles of glial cells in the pathogenesis and healing of tractional macular disorders.

Early Vascular and Functional Changes after Vitreoretinal Surgery: A Comparison between the Macular Hole and Epiretinal Membrane

(1) Background: The aim of this observational comparative study was to investigate early retinal vascular and functional changes in patients undergoing vitreoretinal surgery for idiopathic epiretinal membrane (iERM) or macular hole (MH) using a widefield swept-source optical coherence tomography angiography (WSS-OCTA). (2) Methods: Forty one diseased eyes were enrolled in the study. Twenty three eyes with iERM diagnosis (ERM group) underwent 25-gauge vitrectomy with inner limiting membrane (ILM) and MER peeling, while eighteen eyes with MH (MH group) underwent 25-gauge vitrectomy with inverted flap technique. Functional and anatomical/perfusion parameters were evaluated pre- and postoperatively in all eyes by means of WSS-OCTA system, microperimetry (MP3), best corrected visual acuity assessment, central macular thickness (CMT) and MH diameter calculation. For each eye, 12 × 12 mm OCTA volume scans were acquired by a retinal specialist and a semi-automated algorithm was used for a quantitative vessel analysis of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC). In detail, perfusion density (PD) of the SCP, DCP and CC was evaluated in four circles (one central in the macular area of 5 mm diameter; three midperiphery circles (temporal, superior and inferior) of 3 mm). In addition, the vessel length density (VLD) of the SCP and DCP for the same circles was quantified. (3) Results: In the MH group, PD of the SCP significantly increased in the macular area (p = 0.018) and in the superior ring (p = 0.016); PD of the DCP significantly increased in the macular area (p = 0.015) and in the superior and inferior ring (p = 0.016) 3 months after surgery. In the ERM group, PD of the SCP and DCP significantly increased in the macular area and superior ring, respectively (p = 0.001; p = 0.032), 3 months after surgery. During follow-up there was a significant improvement in terms of functional (Best corrected visual acuity, p = 0.007 and p = 0.029; microperimetry ((MP3) 10°, p = 0.003 and p = 0.004; MP3 2°, p = 0.028 and p = 0.003 in MH group and ERM group respectively) and anatomical parameters (CMT, p = 0.049 in ERM group; hole complete closure in MH group). (4) Conclusions: After vitreoretinal surgery, early retinal vascular and functional changes can be promptly observed and quantified to monitor and potentially predict surgery outcomes. Widefield OCTA devices allow for a detailed microvasculature analysis of retina and choriocapillaris in the macular area and in the periphery, showing a different behaviour of retinal sectors in two distinct vitreoretinal disorders.

Morphological alternation and influence of aqueous flare in idiopathic epiretinal membrane

Background

Idiopathic epiretinal membrane (iERM) is a common retinal disease in the elderly population. The exact pathogenesis of iERM is unknown. The present study aimed to evaluate the relationship between aqueous flare and morphology of iERM using swept-source optical coherence tomography (OCT).

Methods

A consecutive series of 36 eyes of 33 patients with iERM and 109 control eyes of 109 patients were retrospectively examined. Aqueous flare measurements and OCT images were obtained on the same day. The average total retinal, inner retinal, outer retinal, and choroidal thicknesses were calculated using the thickness map mode with an Early Treatment Diabetic Retinopathy Study nine-zone grid that was divided into three zones. The maximum depth of the retinal folds in iERMs was manually measured. The correlation among flare value, maximum depth of folds, and retinal and choroidal thicknesses was evaluated. The morphological changes between the control eyes and the eyes with iERM in different stages were examined.

Results

The result demonstrated a significant positive correlation between the aqueous flare value and total and inner retinal thicknesses in the early stage of iERM. There was a significant positive correlation between the maximum depth of folds and total and inner retinal thicknesses in the early stage of iERM, and the maximum depth of folds significantly increased in the advanced stage. The total and inner retinal thicknesses and proportion of inner retinal thickness significantly increased as the stage of iERM progressed.

Conclusions

The aqueous flare value was associated with retinal thickness in the early stage of iERM, which supports the idea that inflammation or breakdown of blood–ocular barrier is involved in the process of iERM formation. The maximum retinal folds increased as the stage of iERM progressed and retinal thickness increased, which indicates that the tangential force increases as the iERM stage progresses.

Effect of Foveal Vitreous Cortex Removal to Prevent Epiretinal Membrane after Vitrectomy for Rhegmatogenous Retinal Detachment

PURPOSE

To determine the effect of foveal vitreous cortex removal during pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) on the prevention of postoperative epiretinal membrane (ERM) development without internal limiting membrane (ILM) peeling.

DESIGN

Case-control study.

PARTICIPANTS

A total of 105 consecutive eyes of 105 patients who underwent primary PPV for RRD between September 2018 and August 2019 and were followed for at least 6 months.

METHODS

The presence of foveal vitreous cortex during PPV was determined by examining the images obtained by a widefield viewing system in 52 eyes (WF group) operated in the first half of the study period and obtained by a high-magnification floating lens in 53 eyes (FL group) operated in the latter half of the study period. Triamcinolone acetonide was used to make the vitreous cortex more visible during PPV. The foveal vitreous cortex was removed if detected by forceps with a high-magnification floating lens without ILM peeling or use of dye staining. The presence of postoperative ERM was examined by using OCT.

MAIN OUTCOME MEASURES

The rate of detected and removed foveal vitreous cortex during PPV and the incidence of postoperative ERM of each group.

RESULTS

The rate of detected and removed foveal vitreous cortex during PPV was significantly higher in the FL group than in the WF group (41.5% vs. 15.4%, P = 0.004). The incidence of postoperative ERM was significantly lower in the FL group than in the WF group (1.9% vs. 13.5%, P = 0.03). None of the eyes required additional surgery for the postoperative ERM during the follow-up period. The retinal reattachment rate was not significantly different (98.1% vs. 100%, P = 0.99), and the final retinal attachment rate was 100% in both groups. A dissociated optic nerve fiber layer appearance and a temporal macular thinning were not detected postoperatively in any of the eyes with removal of the foveal vitreous cortex during PPV.

CONCLUSIONS

The detection and removal of foveal vitreous cortex with the high-magnification floating lens during PPV for RRD significantly reduce the incidence of postoperative ERM without adverse findings.

Vitreomacular disorders: a review of the classification, pathogenesis and treatment paradigms including new surgical techniques

This review explores how optical coherence tomography has guided our assessment of vitreomacular disorders. Vitreomacular disorders (VMD), such as macular holes and epiretinal membranes are common and potentially sight threatening. The introduction and widespread use of optical coherence tomography (OCT) imaging technology has transformed our ability to visualise the vitreoretinal interface. This review discusses the pathogenesis and updated classification scheme for VMD in the OCT era. Imaging biomarkers and the treatment algorithm, including the role of novel therapeutics, for managing patients with VMD are presented.

Foveal configurations with disappearance of the foveal pit in eyes with macular pucker: Presumed role of Müller cells in the formation of foveal herniation

Many eyes with macular pucker are characterized by a centripetal displacement of the inner foveal layers which may result in a disappearance of the foveal pit. In this retrospective case series of 90 eyes with macular pucker of 90 patients, we describe using spectral-domain optical coherence tomography different foveal configurations with ectopic inner foveal layers, document the relationship between posterior vitreous detachment (PVD) and idiopathic epiretinal membrane (ERM) formation and spontaneous and postoperative morphological alterations of the fovea, and propose an active role of Müller cells in the development of foveal herniation. We found that ERM were formed during or after partial perifoveal PVD, or after foveal deformations caused by tissue edema. The ERM-mediated centripetal displacement of the inner foveal layers and in various eyes anterior hyaloidal traction caused a disappearance of the foveal pit and an anterior stretching of the foveola with a thickening of the central outer nuclear layer (ONL). After the edges of the thickened inner layers of the foveal walls moved together, continuous centripetal displacement of the inner foveal layers generated a bulge of the fovea towards the vitreous (foveal herniation). Macular pseudoholes with a herniation of the inner foveal layers show that the outer layer of the protruding foveal walls is the outer plexiform layer (OPL). If the ERM covered the foveal walls and parafova, but not the foveola, the inner layers of the foveal walls were not fully centripetally displaced and the foveal pit was present. The visual acuity of eyes with ectopic inner foveal layers was inversely correlated with the thickness of the foveal center. Spontaneous morphological alterations after disappearance of the foveal pit may include the development of cystoid macular edema or additional thickening of the foveal tissue and foveal herniation. The foveal configuration with ectopic inner layers of the foveal walls and a thick central ONL persisted over longer postoperative time periods. The data show that the centripetal displacement of the inner foveal layers in eyes with macular pucker, which results in a disappearance of the foveal pit, may also generate foveal herniation which is suggested to be caused by contraction of Müller cell processes in the OPL. The centripetal displacement of the inner foveal layers and the formation of foveal herniation are suggested to reverse the foveal pit formation during development.

Epiretinal Membrane Vitrectomy With and Without Intraoperative Intravitreal Dexamethasone Implant: A Systematic Review With Meta-Analysis

Purpose: To evaluate the efficacy of vitrectomy combined with intravitreal dexamethasone implant vs. vitrectomy without the implant in patients with epiretinal membrane (ERM) by conducting a systematic review and meta-analysis.

Methods: Studies that compared ERM vitrectomy with and without intraoperative dexamethasone implant with a follow-up ≥3 months were included. The primary outcome was mean best corrected visual acuity (BCVA) change between eyes undergoing ERM vitrectomy combined with dexamethasone implant (DEX group) and eyes undergoing ERM vitrectomy alone (control group) at 3 months. Secondary outcomes included mean BCVA change at 6 months and mean optical coherence tomography central macular thickness (CMT) change at both 3-months and 6-months follow-up. Mean differences (MDs) with their 95% confidence interval (95%CI) were calculated. Meta-analyses were based either on random effect model or fixed effect model according to heterogeneity.

Results: Four studies were included. At 3 months, ERM vitrectomy combined with dexamethasone implant yielded a greater visual gain compared to vitrectomy alone (MD = 9.7; 95%CI = 2.6–16.8; p = 0.01). However, significant heterogeneity was found. A sensitivity analysis excluding the only retrospective non-randomized study confirmed a greater visual gain in the DEX group (MD = 7.1; 95%CI = 2.7–11.6; p < 0.01), with no heterogeneity. At 6 months, a non-significant but borderline difference in visual gain was shown between in the two groups (MD = 5.1; 95%CI = −0.3–10.5; p = 0.06), with no heterogeneity. Three-month analysis of CMT revealed a greater reduction in the DEX group (MD = −80.2; 95%CI =−149.1–11.2; p = 0.02), but with significant heterogeneity. A sensitivity analysis excluding the only retrospective non-randomized study allowed to reduce heterogeneity, but no difference in 3-months CMT change was found between the two groups (MD = −50.0; 95%CI = −106.2–6.2; p = 0.08). At 6 months, no difference in CMT change was shown between the two groups (MD = −48.5; 95%CI = −120.5–23.5; p = 0.19), with significant heterogeneity.

Conclusions: Intraoperative dexamethasone implant in eyes undergoing vitrectomy for ERM provided a better visual outcome at 3 months compared to ERM vitrectomy without the implant, with limited evidence of better anatomic outcome as well. Further studies are needed to ascertain whether dexamethasone implant would ensure a significant long-term visual benefit as a result of a faster reduction of macular thickening.

Epiretinal Membrane Surgery after Retinal Detachment Repair: Visual Acuity Outcomes and OCT Analysis

PURPOSE

To assess visual acuity (VA) outcomes of epiretinal membrane (ERM) surgery following primary rhegmatogenous retinal detachment (RD) repair and to identify OCT features predictive of visual outcomes.

DESIGN

Retrospective, consecutive case series.

SUBJECTS

Eyes undergoing pars plana vitrectomy (PPV) with membrane peel (MP) surgery for ERM following primary RD repair (PPV with or without scleral buckle (SB) and gas tamponade).

METHODS

Retrospective chart review from 2015 to 2018. A previously described ERM grading scale was utilized for OCT structural analysis.

MAIN OUTCOME MEASURES

Visual acuity (VA) and change in VA from pre- MP to 6 months and final follow-up. Secondary outcomes included RD and OCT features predictive of VA, as well as RD factors associated with need for subsequent MP surgery.

RESULTS

53 eyes of 53 patients underwent MP following RD repair. VA improved significantly from logMAR 1.00 ± 0.51 (Snellen 20/200) pre-MP to 0.45 ± 0.41 (20/56) at 6 months and 0.42 ± 0.41 (20/53) at final follow-up, (p<0.001) for each respectively. Macula on eyes had better 6 month [0.29 ± 0.18 (20/39) vs. 0.51 ± 0.46 (20/65), p=0.02] and final VA [0.29 ± 0.14 (20/39) vs. 0.46 ± 0.47 (20/58), p=0.04] after MP surgery. VA improved significantly from pre-MP to 6 months and final follow-up regardless of macula status. MP occurring ≤180 days from RD repair and IS/OS loss were associated with worse pre-MP VA [1.13 ± 0.09 (20/270) vs. 0.82 ± 0.07(20/132), p=0.01 and 1.21 ± 0.07 (20/324) vs. 0.74 ± 0.09 (20/110) p=0.0003, respectively]. IS/OS loss [adjusted means 0.54 ± 0.07 (20/69) vs. 0.25 ± 0.08 (20/36) at final visit, p=0.006] and RD repair with PPV/SB [0.53 ± 0.08 (20/68) vs. 0.31 ±0.07 (20/41) at final visit, p=0.03] were significantly associated with worse VA at both 6 months and final follow-up.

CONCLUSIONS

Eyes undergoing MP after RD repair have significant visual acuity gains independent of macula-status at time of RD repair. Pre-operative IS/OS disruption was the OCT feature best predictive of visual acuity.

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 Role of OCT Angiography in the Assessment of Epiretinal Macular Membrane

Background

The aim of this observational study is to assess pre- and postoperative retinochoroidal vascular changes in patients undergoing epiretinal macular membrane (ERM) surgery by using optical coherence tomography angiography (OCTA).

Materials and Methods

23 eyes affected by ERM and those which underwent phacovitrectomy associated with ERM peeling were enrolled. They were evaluated using structural OCT and OCTA before surgery and at 1, 3, and 6 months postoperatively.

Results

We found a statistically significant (p < 0.05) increase in the superficial capillary plexus vessel density (VD) from baseline to the 6-month follow-up. We observed a large increase in both the perfusion density (PD) and the VD of the deep capillary plexus between baseline and the 6-month follow-up (p < 0.001). A significant decrease in the VD and PD of the choriocapillaris (CC) from baseline to the 1^st month and a significant increase in CC perfusion density at the 6-month follow-up compared to the preoperative value were revealed. The FAZ area and perimeter after surgery significantly increased during the follow-up (p < 0.001) at baseline retinal and choroidal plexi with a lower PD or VD correlated with worse visual acuity (p < 0.05 for all plexi). At baseline and at the 1-month follow-up, a significant correlation was found with the FAZ area and the FAZ perimeter: a smaller FAZ area or a smaller FAZ perimeter was correlated to a lower visual acuity. Before surgery, negative correlations (p < 0.05) were found between the Govetto ERM stages and perfusion density of the SCP and the DCP and between the Govetto stages and vessel density of the DCP.

Conclusions

In our study, OCTA detected vascular alterations induced by the presence of the ERM, allowing several correlations with functional data. In these patients, OCTA may be useful to add new potential surgical prognostic factors.

Prediction of Visual Prognosis after Epiretinal Membrane Surgery Using Regression Tree Analysis

Background and Objective: Confounding factors should be considered when predicting visual prognosis after epiretinal membrane (ERM) surgery. We aimed to predict visual acuity after ERM surgery using regression tree analysis.Patients and Methods: We retrospectively reviewed 343 eyes of 343 patients who underwent vitrectomy for idiopathic ERM. Regression tree analysis was performed to predict best-corrected visual acuity (BCVA) at 6 months postoperatively.Results: Patients were first divided into two groups based on preoperative BCVA. Age, central macular thickness, and axial length were associated with visual prognosis in patients with specific preoperative BCVAs. When patients were subdivided into groups 1-8, BCVA was significantly better in group 1 than in groups 4-8 (p≤0.001), and in groups 2-5 and 7 than in groups 6 and 8 (p≤0.002).Conclusion: Surgical prognosis in eyes with ERM should be evaluated based on a comprehensive assessment of preoperative characteristics.

A novel quantitative analysis method for idiopathic epiretinal membrane

PURPOSE

To introduce a novel method to quantitively analyse in three dimensions traction forces in a vast area of the ocular posterior pole.

METHODS

Retrospective analysis of 14 eyes who underwent peeling surgery for idiopathic, symptomatic and progressive epiretinal membrane. The technique measures the shift in position of vascular crossings after surgery from a fixed point, which is the retinal pigmented epithelium. This shift is defined as the relaxation index (RI) and represents a measure of the postoperative movement of the retina due to released traction after surgery.

RESULTS

Best-corrected visual acuity was significantly better than baseline at all follow ups while the RI had its maximum value at baseline. Moreover, we found a significant correlation between best-corrected visual acuity at 6 months and RI at baseline.

CONCLUSION

While all previous published methods focused on bi-dimensional changes observed in a small region, this study introduces a three-dimensional assessment of tractional forces. Future integration of RI into built-in processing software will allow systematic three-dimensional measurement of intraretinal traction.

Assessment of epiretinal membrane formation using en face optical coherence tomography after rhegmatogenous retinal detachment repair

PURPOSE

To investigate epiretinal membrane (ERM) formation using en face optical coherence tomography (OCT) after vitrectomy for rhegmatogenous retinal detachment (RRD).

METHODS

We retrospectively reviewed the medical records of 64 consecutive eyes (64 patients) with RRD treated by vitrectomy without ERM and internal limiting membrane peeling. ERMs and retinal folds were detected by B-scan and en face imaging. The maximum depth of retinal folds (MDRF) was quantified using en face imaging. ERM severity was staged using B-scan imaging. Main outcome measures were ERM detection rate with B-scan and en face imaging, MDRF, ERM staging, postoperative best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution), and risk factors for ERM formation.

RESULTS

The detection rate for ERM formation was significantly higher with en face imaging (70.3%) than with B-scan imaging (46.9%; P = 0.007). There was no significant difference in postoperative BCVA between eyes with ERM formation (0.06 ± 0.26) and those without ERM formation (0.01 ± 0.14; P = 0.298). Forty of 45 (88.9%) eyes with ERM formation were classified as stage 1. Twenty-seven of 45 (60.0%) eyes with ERM formation developed parafoveal retinal folds. The mean MDRF was 27.4 ± 32.2 μm. Multiple retinal breaks and a maximum retinal break size of ≥ 2 disc diameters were significantly associated with ERM formation (P = 0.033 and P = 0.031, respectively).

CONCLUSION

Although ERM formation was observed in 70.3% patients after RRD repair, the formed ERM was not severe and had minimal impact on the postoperative visual acuity.

[Retinal imaging of vitreomacular traction diseases]

Advances in imaging techniques of the retina have substantially enhanced our current understanding of the pathogenesis, morphology and prognosis of vitreomacular retinal diseases. Optical coherence tomography-based criteria and classification systems were recently proposed for uniform diagnoses and treatment recommendations for patients with vitreomacular traction, epiretinal gliosis and the various forms of macular holes. This article provides an overview of the different retinal imaging modalities as well as the currently recommended classification for vitreomacular traction pathologies.

[Optical coherence tomography biomarkers in epimacular membranes and vitreomacular traction syndrome]

Using high-resolution imaging, such as optical coherence tomography (OCT), the different layers of the retina as well as the vitreoretinal interface and its alterations can be very clearly differentiated. This includes the morphological characteristics of tractive maculopathies, such as epiretinal gliosis and vitreomacular traction syndrome. Additionally, structural alterations of the various layers of the neurosensory retina as a result of traction due to these pathologies can be demarcated. The latter have been investigated in clinical trials and evaluated as OCT biomarkers with respect to their prognostic and predictive value. In this review we would like to present and discuss various OCT biomarkers in the context of epimacular membranes and vitreomacular traction syndrome.

PREOPERATIVE DOMED MACULAR CONTOUR CORRELATES WITH POSTOPERATIVE VISUAL GAIN AFTER VITRECTOMY FOR SYMPTOMATIC EPIRETINAL MEMBRANE

PURPOSE

Evaluate macular features on preoperative ocular coherence tomography as indicators of postoperative visual gain following vitrectomy for epiretinal membrane (ERM).

METHODS

A retrospective chart review of 66 eyes that underwent vitrectomy with membrane and internal limiting membrane peeling for symptomatic ERM. Inclusion criteria required a pre-op visual acuity of at least 20/200 and minimum follow-up of 1 year. In addition, 31 of these eyes with complete 5-line raster pre-op ocular coherence tomography had segmentation analysis which included noncentral ERM to inner nuclear layer and ERM to outer plexiform layer measurements.

RESULTS

Eyes with "domed" pre-op macular contour had a mean preoperative acuity of 20/70 and gained a mean 2.4 lines at one year, compared with those with "flat" or "depressed" macular contour, having a 20/60 mean preoperative acuity and 0.6 lines gained (P = 0.02). Changes for other ocular coherence tomography features examined were not statistically significant. Paracentral ERM to inner nuclear layer measurements had moderate correlation, whereas paracentral ERM to outer plexiform layer measurements had weak correlation with gain in visual acuity.

CONCLUSION

An inner macular-domed contour in eyes with ERM predicted better visual gain after vitrectomy with ERM and internal limiting membrane peeling compared with a flat or depressed contour.

Long-term follow-up of retinal sensitivity assessed by microperimetry in patients with internal limiting membrane peeling

PURPOSE

To evaluate anatomical and functional changes in patients with vitreomacular interface disease after internal limiting membrane (ILM) peeling, using microperimetry along with usual clinical and multimodal retinal imaging.

METHODS

Patients with vitreomacular interface disease requiring vitrectomy underwent multimodal retinal evaluation, including visual acuity assessment, fundus color photograph, Spectral-Domain Optical Coherence Tomography, Optical Coherence Tomography-Angiography, and microperimetry. They were examined at baseline (M0), 6 months (M6) and 18 months (M18) after surgery. Retinal sensitivity was subdivided into three concentric polygons: Large, Medium, Small.

RESULTS

Eleven eyes of 11 patients were analyzed, including 10 epiretinal membranes (ERMs). Best-corrected visual acuity (BCVA) improved in all patients from 0.51 logarithm of the minimal angle of resolution (logMAR) to 0.067 (p = 0.0074). Retinal sensitivity improved between M0 and M6 in all polygons and continued to improve between M6 and M18 for polygons Medium (M) and Small (S) with no statistical significance. At M18, BCVA and retinal sensitivity were similar in the operated eye compared with the fellow eye for all patients. Dissociated optic nerve fiber layer appearance was observed in 8 patients at M18. It was not correlated with either retinal sensitivity or BCVA or microscotomas. No recurrence of ERM or macular hole occurred during follow-up.

CONCLUSION

After surgery, the retinal sensitivity assessed by microperimetry gradually improved until the 18th month and was not different from the values of the fellow eye. These results seemed to confirm that ILM peeling can be an effective and safe technique to treat patients with vitreomacular interface disease.

Prognostic factors of idiopathic epiretinal membrane surgery and evolution of alterations of the central cone bouquet

PURPOSE

To describe the structural changes observed postoperatively in epiretinal membranes (ERM), in particular the alterations in the central cone bouquet (CB), and to identify prognostic factors that might predict postoperative outcome.

METHODS

We included 125 eyes of 117 patients who underwent idiopathic ERM removal with at least a 6-month follow-up. For each patient, spectral-domain optical coherence tomography (SD-OCT) was performed and best-corrected visual acuity (BCVA) was measured, before and after surgery.

RESULTS

Before surgery, 44 eyes (35.2%) presented CB alterations: 65.9% a cotton ball sign, 15.9% a foveolar detachment and 18.2% a pseudovitelliform lesion. Median BCVA increased from 20/63 to 20/32 post-operatively (p = .001) with a mean follow-up of 17 months. The disappearance of CB alterations after surgery was observed in 97.7% of eyes. In stage 3 and 4 ERM, ectopic inner foveal layers persisted in 76.7% of eyes after surgery. Postoperative BCVA was correlated with change in central macular thickness and initial BCVA and was not correlated with the presence of preoperative CB alteration, the initial stage of ERM, the presence of postoperative dissociated optical nerve fiber layer, and the disappearance of ectopic inner fiber layers. The combination of cataract surgery and capsulotomy did not seem to change visual outcome and seemed to accelerate visual recovery. Incidentally, general anesthesia was correlated with final BCVA.

CONCLUSION

ERM surgery allowed a significant gain in BCVA and the disappearance of CB alterations in the great majority of cases. CB alteration did not show to be associated with poor visual prognosis.

Functional and Morphological Results of Epiretinal Membrane Surgery in Idiopathic versus Diabetic Epiretinal Membranes

PURPOSE

Idiopathic and diabetic epiretinal membranes (ERM) are different in terms of pathophysiology, etiology, and macular morphology, and thus might respond to surgical treatment differently. We aimed to compare the surgical results of two groups.

METHODS

Retrospective case series study of 71 eyes of 66 patients who underwent pars plana vitrectomy (PPV) due to idiopathic or diabetic ERM with at least 1-year follow-up. Examinations were performed before, and 1, 3, 6, and 12 months after surgery. The average macular thicknesses in nine sectors described by the Early Treatment Diabetic Retinopathy Study (ETDRS) were measured with spectral-domain optical coherence tomography (OCT), and BCVA was evaluated. ERM recurrence rates were investigated.

RESULTS

In both idiopathic and diabetic groups, retinal thickness (RT) changes occurred as long as 12 months after vitrectomy surgery for ERM. However, in the idiopathic group, significant changes were mainly seen in the first 6 months, while in the diabetic group changes slowed considerably between the third and sixth months, but again accelerated (becoming significant) during the last 6 months.

CONCLUSIONS

According to the findings of this study, as compared to those with idiopathic ERM, diabetic patients would likely see continuing benefits from ERM surgery 6 to 12 months post surgery. The BCVA changes of the two groups were similar. ILM peeling decreased ERM recurrence in the idiopathic group but not in the diabetic group.

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.

Influences of Central Bouquet Alterations on the Visual Outcome in Eyes Receiving Epiretinal Membrane Surgery

Background: Previous studies have shown that epiretinal membranes (ERMs) may be associated with abnormal outer retinal anatomy. However, long-term morphological and functional results of pars plana vitrectomy (PPV) with ERM and internal limiting membrane (ILM) peeling in eyes with central bouquet (CB) alterations have not yet been investigated. Methods: In a retrospective, consecutive study all patients underwent best corrected visual acuity (BCVA) testing and spectral domain optical coherence tomography (SD-OCT) before and after a mean of 20 months (range 3–70 months) postoperatively. CB abnormalities and ERMs were classified according to Govetto’s staging systems. Results: Of the 67 eyes, 22 (34%) showed CB abnormalities at baseline. The mean BCVA increased from 0.42 at baseline to 0.20 LogMAR at final follow-up (p < 0.001). Neither ERM stage (p = 0.06) nor CB stage (p = 0.939) at baseline were significant predictors of vision improvement following surgery. Conclusions: Our results show that baseline BCVA, but not classification of CB changes and ERM at baseline, seems to be a useful predictor for functional outcomes following PPV with ERM and ILM peeling in the long-term.

Epiretinal membrane surgery outcome in eyes with abnormalities of the central bouquet

Background

Clinical studies have shown that epiretinal membranes (ERM) as well as abnormalities of the central foveal bouquet (CB) can be classified in different stages according to their morphological appearance. Furthermore, visual acuity correlates with the different stages of these features. The present study evaluated how these findings change after the surgical removal of the ERM and their impact on functional outcomes.

Methods

In this retrospective study eyes with ERM were evaluated by SD-OCT scans before and after pars plana vitrectomy (PPV) with macular ERM and internal limiting membrane (ILM) peeling. CB abnormalities were classified according to their morphological appearance from stage 0 (no abnormalities) to stage 3 (acquired vitelliform lesion). ERMs were classified ranging from stage 0 (absence of ERM) to stage 4 (ERM with significant anatomic disruption of macula). Changes in morphology were correlated with visual acuity before and after surgery.

Results

151 eyes were included into the study. Before surgery 27.2% (n = 41) of eyes showed CB abnormalities with stage 1 being the most common (11.9%, n = 18). Before surgery ERM was seen in all patients. The most common form was stage 1 (28.5%, n = 43), followed by stage 3 (27.8%, n = 42) and 2 (25.2%, n = 38). Only 18.5% (n = 28) presented with stage 4 ERM. The mean BCVA was 0.42 (logMAR) before and increased to 0.19 (logMAR) 8 weeks after vitrectomy (95% CI 0.20–0.28; p < 0.001). Patients who suffered from CB abnormalities had less increase in BCVA than patients who had no evidence of CB (0.28 vs. 0.14 logMAR; p < 0.001). Of all the patients with CB abnormalities at baseline, 68% had lower CB grading after the surgery (n = 28; 95% CI; p < 0.001). All patients showed an improvement of their ERM grading, with 98.7% reaching stage 0 (n = 151 vs. n = 149; 95% CI; p < 0.001).

Conclusions

The study indicates that the presence of CB abnormalities correlates with worse visual function. They are furthermore associated with worse visual outcomes after PPV with ERM and ILM peeling. These findings are valuable for deciding on PPV in patients with ERM.