"Dissociated optic nerve fiber layer appearance" after internal limiting membrane removal is inner retinal dimpling

THE ROLE OF GLIOSIS IN IDIOPATHIC EPIRETINAL MEMBRANES: New Insights

PURPOSE

To compare cloudy and clear epiretinal membranes (ERMs) using Multicolor Scanning Laser Ophthalmoscopy (MC-SLO) per stage and to assess gliotic components' impact on postoperative visual outcomes in patients undergoing surgery.

METHODS

Baseline and 6-month measurements included Snellen acuity (SA), central retinal thickness (CRT), the presence of microcystic macular edema (MME), outer retinal cysts (ORCs), and disruptions of the ellipsoid zone (EZ) and external limiting membrane (ELM). In addition, a quantitative analysis of gliosis using MC-SLO was performed. This study primarily evaluated postoperative SA improvement, CRT reduction, the prevalence of ERM remnants and inner retinal dimples. In addition, the relationship between gliotic components and postoperative outcomes was analyzed.

RESULTS

In Stage 2 ERMs, clear ERMs had a higher incidence of ERM remnants after surgery (81.8% vs. 30.8%, P = 0.037). Both groups experienced visual acuity improvement (clear ERMs: +25 ETDRS letter score, cloudy ERMs: +15 ETDRS letter score P = 0.013). In Stage 3 ERMs, no significant differences in SA or CRT changes were noted, but clear ERMs showed more inner retinal dimples ( P = 0.015). Gliosis area and EIFL thickness showed a significant correlation in cloudy Stage 3 ERMs ( P = 0.011).

CONCLUSION

Clear and cloudy ERMs differ in postoperative recovery. Cloudy Stage 2 ERMs have less functional recovery but fewer remnants than clear ERMs. In Stage 3, gliosis correlates with EIFL thickness, and clear ERMs exhibit more inner retinal dimples.

En face OCT: Breakthroughs in understanding the pathoanatomy of retinal disease and clinical applications

En face optical coherence tomography (OCT) is a practical and informative imaging modality to noninvasively visualize distinct retinal and choroidal layers by providing coronal images using boundary-specific segmentation. Ongoing research with this method is generating breakthroughs in the illustration of new perspectives of retinal disease. The clinical value of en face OCT as an advanced retinal imaging tool is growing steadily and it has unveiled many new insights into the pathoanatomy of retinal disorders. Moreover, this modality can capture various en face OCT biomarkers that correspond to different cell or tissue subtypes, which were previously only identified through histological or electron microscopy methods, underscoring the significance of this technique in providing valuable pathoanatomical information. In this comprehensive review, we will systematically summarize the en face OCT findings across a broad spectrum of retinal diseases, including disorders of the vitreoretinal interface and retinal vascular system (e.g. paracentral acute middle maculopathy or PAMM and diabetic retinopathy), in addition to the en face OCT features of other conditions such as age-related macular degeneration, pachychoroid disease spectrum, myopic degeneration, uveitis and inflammatory disorders, inherited retinal dystrophies, and drug toxicity. We will discuss and highlight the unique clinical and pathoanatomical findings uncovered with en face OCT of each these diseases mentioned above.

Assessment of clinical outcomes and prognostic factors following membrane peeling in idiopathic epiretinal membrane using EIFL staging system: an optical coherence tomography angiography analysis

BACKGROUND

To evaluate the associations between anatomical changes and visual outcomes after membrane peeling in eyes with different stages of idiopathic epiretinal membrane (iERM) using optical coherence tomography angiography (OCTA).

METHODS

All iERM eyes were graded into four stages based on the presence of ectopic inner foveal layers (EIFL) and underwent 23-gauge vitrectomy combined with ERM and internal limiting membrane (ILM) peeling, while their fellow eyes were treated as the control group. OCTA was used to measure retinal thickness(RT), foveal avascular zone (FAZ)-related parameters and superficial and deep capillary plexus (SCP and DCP) layers using 6 × 6 mm scans before, 1 month and 3 months after surgery. In addition, best corrected visual acuity (BCVA), metamorphopsia and macular features were assessed.

RESULTS

Forty-six subjects were included in this study. In comparison to the preoperative data, visual acuity and metamorphopsia improvement was statistically significant in four stages(P < 0.05) and the higher stage (3 and 4) achieved more pronounced improvements (P = 0.002). For higher stage, RT reduced with an increase in stage(P < 0.001), superficial and deep foveal vessel density (SFVD and DFVD) and parafoveal vessel density (PRVD) in SCP declined remarkably, FAZ area was enlarged obviously, FAZ perimeter (PERIM), foveal vessel density (FD) and PRVD in DCP increased significantly after surgery (P < 0.05). Similar to high-stage patients, those with stage 2 iERMs demonstrated a decreasing trend in central macular thickness (CMT), paraRT (parafoveal thickness), SFVD, and DFVD(P < 0.05). Nevertheless, no notable alterations were observed in other indicators. Distinct from other groups, only CMT and FD increased slightly in stage 1 iERMs (P < 0.05). Post-LogMAR BCVA and LogMAR BCVA-d (pre-LogMAR BCVA -3-month post-LogMAR BCVA) were positively correlated with preoperative stages, CMT, pre-LogMAR BCVA, SFVD, and vascular tortuosity(P < 0.05). but negatively correlated with FAZ area and DFVD (P < 0.05). Preoperative and postoperative metamorphopsia had a certain positive correlation with preoperative CMT (P < 0.05).

CONCLUSIONS

According to OCTA analysis, different EIFL stages of iERMs showed significantly functional and anatomic differences before and after membrane peeling. Low-stage patients have better post-op visual function, while high-stage patients benefit more from surgery. It also demonstrated EIFL staging system contribute doctors to manage iERMs.

Three-Dimensional Quantitative Analysis of Internal Limiting Membrane Peeling Related Structural Changes in Retinal Detachment Repair

PURPOSE

To assess macular microstructural changes associated with internal limiting membrane peeling (ILMP) using 3-dimensional optical coherence tomography (3D-OCT) in primary macula-off rhegmatogenous retinal detachment (RRD) repairs with vitrectomy and silicone oil (SO) tamponade.

DESIGN

Retrospective, consecutive, interventional case series.

METHODS

Setting: Institutional practice.

PATIENT POPULATION

Patients who received primary RRD repair by a single experienced surgeon between January 2017 and December 2021.

MAIN OUTCOME MEASURES

In the qualitative comparative analysis, the presence of macular changes among patients who underwent primary RRD repair with (21 eyes) or without ILMP (20 eyes) were observed. Subsequently, a detailed quantitative analysis of ILMP-related microstructural changes in 56 eyes using both 3D and 2D-OCT images were performed.

RESULTS

In the qualitative comparative analysis, macular microstructural changes were observed in 95% of ILMP eyes and 5% of non-ILMP eyes (p < .001). In the quantitative analysis, 4 major macular microstructural changes were detected: dimple (75%), dissociated nerve fiber layer (DONFL) (55%), ILM peeling edge thinning (IPET) (64%), and temporal macular groove (TMG) (23%). Dimples (n = 251, average 4.5 ± 5.8 per eye) could be further classified into type I (confined to the inner plexiform layer [IPL]; 73%) and type II (beyond IPL, 27%). The average depth of the deepest dimples was 58 ± 18 µm. The extent of IPET was 6.0 ± 3.7 clock hours. The average length of TMG was 1.8 ± 0.4 mm. Comparing to unoperated fellow eyes, the eyes after ILMP showed decreased inner temporal over nasal retinal thickness ratio (0.86 ± 0.07 versus 0.96 ± 0.03, p < .001), shorter disc-fovea distance (4.61 ± 0.32 µm versus 4.78 ± 0.37 µm, p = .041), and wider retinal vein trajectories (c' = 2.48 ± 0.84 vs 3.39 ± 1.61, p = .002).

CONCLUSIONS

Macular microstructural changes are common after ILMP in RRD repair, encompassing both focal changes (dimples, DONFL) and zonal changes (IPET, TMG). DONFL and dimples may be part of a continuum of findings stemming from the same mechanism. IPET and TMG are the results of macular tissue shift due to contracture of the optic disc and neurovascular bundle.

RANDOMIZED TRIAL COMPARING MICROSERRATED VERSUS CONVENTIONAL INTERNAL LIMITING MEMBRANE FORCEPS FOR INTERNAL LIMITING MEMBRANE PEELING

PURPOSE

To evaluate anatomic outcomes and surgeon response following the use of microserrated (Sharkskin, Alcon, Forth Worth, TX) internal limiting membrane (ILM) forceps compared with conventional (Grieshaber; Alcon) ILM forceps for peeling of the ILM.

METHODS

Patients were prospectively assigned in a 1:1 randomized fashion to undergo ILM peeling using microserrated forceps or conventional forceps. Rates of retinal hemorrhages, deep retinal grasps, ILM regrasping, time to ILM removal, and surgeon questionnaire comparing the use of microserrated and conventional ILM forceps were analyzed.

RESULTS

A total of 90 eyes of 90 patients were included in this study. The mean number of deep retinal grasps was higher in the conventional forceps group (1.51 ± 1.70 vs. 0.33 ± 0.56, respectively [P < 0.0001]). The mean number of failed ILM grasps was higher with conventional forceps (6.62 ± 3.51 vs. 5.18 ± 2.06 [P = 0.019]). Microserrated forceps provided more comfortability (lower number) in initiating the ILM flap (2.16 ± 0.85 vs. 1.56 ± 0.76, P < 0.001), comfortability in regrasping the ILM flap (2.51 ± 1.01 vs. 1.98 ± 0.89, P = 0.01), and comfortability in completing the ILM flap (2.42 ± 1.03 vs. 1.84 ± 1.02, P = 0.01).

CONCLUSION

Surgeons utilizing the microserrated forceps experienced fewer deep retina grasps and fewer failed ILM grasps compared with conventional ILM forceps. The microserrated forceps was also a more favorable experience subjectively among the surgeons.

Imaging the Area of Internal Limiting Membrane Peeling after Macular Hole Surgery

Background: The aim of this study was to compare en-face optical coherence tomography (OCT) imaging and confocal scanning laser ophthalmoscopy (cSLO) imaging at different wavelengths to identify the internal limiting membrane (ILM) peeling area after primary surgery with vitrectomy and ILM peeling for macular hole (MH). Methods: In total, 50 eyes of 50 consecutive patients who underwent primary surgery with vitrectomy and ILM peeling for MH were studied. The true ILM rhexis based on intraoperative color fundus photography was compared to the presumed ILM rhexis identified by a blinded examiner using en-face OCT imaging and cSLO images at various wavelengths. To calculate the fraction of overlap (FoO), the common intersecting area and the total of both areas were measured. Results: The FoO for the measured areas was 0.93 ± 0.03 for en-face OCT, 0.76 ± 0.06 for blue reflectance (BR; 488 nm), 0.71 ± 0.09 for green reflectance (GR; 514 nm), 0.56 ± 0.07 for infrared reflectance (IR; 815 nm) and 0.73 ± 0.06 for multispectral (MS). The FoO in the en-face OCT group was significantly higher than in all other groups, whereas the FoO in the IR group was significantly lower compared to all other groups. No significant differences were observed in FoO among the MS, BR, and GR groups. In en-face OCT, there was no significant change in the ILM peeled area measured intraoperatively and postoperatively (8.37 ± 3.01 vs. 8.24 ± 2.81 mm2; p = 0.8145). Nasal-inferior foveal displacement was observed in 38 eyes (76%). Conclusions: En-face OCT imaging demonstrates reliable postoperative visualization of the ILM peeled area. Although the size of the ILM peeling remains stable after one month, our findings indicate a notable inferior-nasal shift of the overall ILM peeling area towards the optic disc.

EFFICIENCY AND SAFETY OF INTERNAL LIMITING MEMBRANE PEELING WITH DIFFERENT FORCEPS FOR MACULAR DISEASE

PURPOSE

To compare the efficiency and safety of internal limiting membrane (ILM) peeling between the Sharkskin forceps and End-grasping forceps in various macular diseases.

METHODS

It is a prospective cohort block-randomized study conducted in a tertiary medical center. Seventy subjects with macular hole, epiretinal membrane, vitreomacular traction syndrome, or myopic foveoschisis, receiving pars plana vitrectomy and ILM peeling surgery were equally divided into Sharkskin forceps group and End-grasping forceps group. The duration of ILM peeling, the number of attempts to initiate peeling, and peeling-related retinal damage were evaluated by recorded video and optical coherence tomography.

RESULTS

In the Sharkskin group, the authors demonstrated significantly fewer attempts to initiate ILM peeling compared with End-grasping group, with an average of 1.9 and 3.1 attempts ( P = 0.0001) and a lower incidence of retinal microstructural damage (20% vs. 45%, P < 0.0001). Moreover, the mean depth of inner retinal injury at the initiating site exhibited distinct difference postoperatively at 3 months between the Sharkskin group then the End-grasping group (4.3 vs. 30.0 µ m, P = 0.001).

CONCLUSION

Sharkskin forceps provide better efficiency and outcome in ILM peeling in patients with various vitreomacular interface diseases, including reduced risk of retinal injury and fewer attempts to initiate ILM flap.

Internal limiting membrane peeling in rhegmatogenous retinal detachment: A meta-analysis

PURPOSE

To determine whether pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling for rhegmatogenous retinal detachment (RRD) could get better functional and anatomical outcomes.

METHODS

A comprehensive literature search was performed to find relevant studies. A meta-analysis was conducted by comparing the weighted mean differences (WMD) in the mean change of best corrected visual acuity (BCVA) from baseline and calculating the odd ratios (OR) for rates of epiretinal membrane (ERM) formation and recurrence of retinal detachment (RD).

RESULTS

Fourteen studies were selected, including 2259 eyes (825 eyes in the ILM peeling group and 1434 eyes in the non-ILM peeling group). There was no significant difference in terms of mean change in BCVA from baseline and the rate of RD recurrence (WMD = 0.02, 95% CI, -0.20 to 0.24, P = 0.86, and OR = 0.55, 95% CI, 0.24 to 1.26, P = 0.16), but ILM peeling was associated with a significantly lower frequency of postoperative ERM formation (OR = 0.13, 95% CI, 0.06 to 0.26, P<0.00001). Similar results were obtained in a sub-analysis based on macula-off RRD.

CONCLUSION

ILM peeling results in similar BCVA, with same rate of RD recurrence, but lower rate of postoperative ERM development. ILM peeling could be considered in selected cases with risk factors that are likely to develop an ERM.

Microperimetry-guided inverted internal limiting membrane flap site selection to preserve retinal sensitivity in macular hole with glaucoma

Purpose

In cases of macular hole (MH) that is difficult to close, including large, chronic, or highly myopic cases, the inverted internal limiting membrane (ILM) flap technique is often preferred and yields favorable surgical outcomes as compared to those yielded by conventional ILM peeling. However, no consensus exists on the optimal location and area for peeling and inverting the ILM, since multiple alternative methods have been reported alongside the original method. Several adverse effects associated with ILM peeling have been documented, including mechanical impairment of the retinal nerve fiber layer and decreased retinal sensitivity. Particularly, when glaucoma is concomitant, the retinal nerve fiber layer is fragile, raising concerns about a decrease in retinal sensitivity. Consequently, in patients with large MH alongside glaucoma, the goal is to select a procedure that maximizes the closure rate of the MH while minimizing any negative impact on glaucomatous visual field impairment. However, a technique for this purpose has not yet been validated.

Observations

A woman in her 60s presented with visual impairment (20/50), metamorphopsia, and central scotoma of unknown onset in the right eye. A full-thickness MH accompanied by epiretinal proliferation (EP) was identified, with a minimum diameter of 506 μm. Although a retinal nerve fiber layer defect was not evident on ophthalmoscopy, thinning of the ganglion cell complex (GCC), extending from the superotemporal aspect of the optic disc, was observed on optical coherence tomography. Both microperimetry and static visual field testing revealed reduced retinal sensitivity in the thinned GCC areas. A pars plana vitrectomy combined with cataract surgery was performed to address her condition. The EP was embedded into the foveal cavity. On the basis of the microperimetry results, the ILM within the absolute scotoma region was peeled on the superotemporal side of the fovea to create a flap, which was then placed over the MH. A gas tamponade was applied, and the patient was maintained in a prone position postoperatively. The MH was successfully closed after the surgery, resulting in visual improvement (20/25). No decline in retinal sensitivity after the surgery was observed.

Conclusions and importance

Determining the location and area of the inverted ILM flap on the basis of microperimetry results is a promising patient-tailored strategy for treating MH concomitant with glaucoma while preventing further ILM peeling-associated reduction in the retinal sensitivity.

Evaluation of OCTA-based Parameters in Full-thickness Macular Holes: A Prospective, Comparative, Interventional Study

PURPOSE

This study aims to correlate optical coherence tomography angiography (OCTA)-based retinal microvasculature changes in cases of full-thickness macular hole (FTMH) before and after vitreoretinal surgery and its relation to patient's visual recovery.

METHODS

Data of 31 eyes with FTMH were evaluated preoperatively and post-operatively at 6, 12, and 24 weeks for OCTA parameters and compared.

RESULTS

93.55% eyes (29 eyes) showed improvement in best-corrected visual acuity at 24 weeks. The mean foveal avascular zone (FAZ) significantly reduced from 0.41 ± 0.13 mm2 (preoperatively) to 0.25 ± 0.01 mm2 (postoperatively at 24 weeks). Mean preoperative vessel density (VD) in the superficial vascular plexus (SVP) progressively improved to 24.2% ± 2.2%, 25.2% ± 2.1% and 25.8% ± 2.3% at 6, 12, and 24 weeks respectively from 24.4% ± 2.1% preoperatively (P = 0.0, F = 5.1). The mean VD of foveal region in the SVP significantly improved (P < 0.0, F = 13.9) while that of the parafoveal region did not improve at 24 weeks (P = 0.3, F = 1.2) when compared with its preoperative status. The mean preoperative VD in the deep vascular plexus (DVP) was 20.2% ± 2.6%. It significantly improved at 6, 12, and 24 weeks (20.3% ± 2.4%, 21.8% ± 2.3% and 22.1% ± 2.2%, respectively; P = 0.0, F = 6.9). The mean VD of foveal region and parafoveal region in the DVP showed significant improvement when compared with its preoperative status (P < 0.0, F = 39.3, P < 0.0, F = 13.7).

CONCLUSION

This study showed reduction in mean FAZ area and improvement in mean VD at SVP and DVP in the macula postoperatively. Routine perioperative OCTA-based documentation of macular vascularity in FTMH may throw a light in cases with anatomico-functional postoperative disparities in future.

PORES OF THE INTERNAL LIMITING MEMBRANE: A Common Finding in Vitreomaculopathies

PURPOSE

To describe presence and distribution of pores of the inner limiting membrane (ILM) in eyes with vitreomaculopathies.

METHODS

Inner limiting membrane specimens were harvested from 117 eyes of 117 patients during vitrectomy with membrane peeling from eyes with vitreomacular traction syndrome, idiopathic and secondary epiretinal gliosis, and idiopathic full-thickness macular hole. All specimens were processed as flat-mounts for immunocytochemistry and examined by phase-contrast, interference, and fluorescence microscopy. Demographic and clinical data were correlated.

RESULTS

Inner limiting membrane pores were found in all vitreomaculopathies. They were identified in 47 (40.2%) of 117 eyes being most evident with antilaminin. In eyes with full-thickness macular hole >400 µ m, pores were seen in more than half of all eyes. They occur as numerous and uniformly distributed defects of the flat-mounted ILM with a mean diameter of 9.5 ± 2.4 µ m. Edges of ILM pores are round with an irregular contour and no specific cellular pattern. Pores were distinguished from retinal vessel thinning and iatrogenic artefacts.

CONCLUSION

Contrary to previous reports, ILM pores are a common finding in vitreomaculopathies easily visible with antilaminin staining. Further studies are needed to clarify whether their presence correlates with differences in disease progression or imaging before and after vitrectomy with ILM peeling.

THREE-DIMENSIONAL HEADS-UP VITRECTOMY VERSUS CONVENTIONAL MICROSCOPIC VITRECTOMY FOR PATIENTS WITH EPIRETINAL MEMBRANE

PURPOSE

To investigate the efficacy and safety of 3D heads-up display (3D-HUD) vitrectomy compared with conventional microscopy (CM) vitrectomy in epiretinal membrane (ERM) surgery.

METHODS

Epiretinal membrane removal with or without internal limiting membrane (ILM) peeling was performed using a 3D-HUD or CM system. The mean changes in best-corrected visual acuity (BCVA) and in central macular thickness (CMT) and postoperative complications were assessed.

RESULTS

Baseline demographics were comparable except for the follow-up period. Both BCVA and CMT improved at the final visit (all P < 0.05). The ERM recurrence and dissociated optic nerve fiber layer (DONFL) rates were lower in the 3D group (both P < 0.05). conventional microscopic vitrectomy (odds ratio [OR] = 12.86, P = 0.02) and absence of ILM peeling (OR = 45.25, P < 0.05) were associated with ERM recurrence. In the DONFL, CM vitrectomy (OR = 1.98, <0.05) and combined phacovitrectomy (OR = 2.33, P = 0.03) were analyzed as risk factors for DONFL.

CONCLUSION

The improvement in BCVA and CMT in ERM surgery using a 3D-HUD is comparable with that of CM vitrectomy, with a significantly low rate of ERM recurrence and DONFL occurrence. Therefore, 3D vitrectomy might have an advantage for ERM surgery.

Effect of Macular Internal Limiting Membrane Peeling on Single Surgery Success Rates of Vitrectomy for Uncomplicated, Primary Macula-Off Retinal Detachment

Purpose: To determine the anatomic and visual outcomes of pars plana vitrectomy for uncomplicated, primary macula-off rhegmatogenous retinal detachment (RRD) with and without internal limiting membrane (ILM) peeling. Methods: This retrospective chart review comprised 129 patients with uncomplicated, primary macula-off RRD presenting between January 1, 2016, and May 31, 2021. Thirty-six patients (27.9%) had ILM peeling and 93 (72.0%) did not. The primary outcome was the rate of recurrent RRD. Secondary outcomes included preoperative and postoperative best-corrected visual acuity (BCVA), epiretinal membrane (ERM) formation, and macular thickness. Results: No significant difference was found in the risk for recurrent RRD between patients who had ILM peeling and those who did not (2.8% [1/36] and 5.4% [5/93], respectively) (P = 1.00). The final postoperative BCVA was better in eyes that did not have ILM peeling (P< .001). No ERM occurred in the group with ILM peeling, whereas ERM occurred in 27 patients (29.0%) who did not have ILM peeling. The temporal macular retina was thinner in eyes in which ILM peeling was performed. Conclusions: The risk for recurrent RRD was not statistically lower in eyes having ILM peeling of the macula in uncomplicated, primary macula-off RRD. Despite a reduction in postoperative ERM formation, eyes having macular ILM peeling had worse postoperative VA.

Quantitative evaluation of dissociated optic nerve fibre layer (DONFL) following idiopathic macular hole surgery

OBJECTIVES

To quantitatively evaluate concentric macular dark spots (CMDS) on spectral-domain optical coherence tomography (SD-OCT) to determine the morphological characteristics of dissociated optic nerve fibre layer (DONFL) following the performance of internal limiting membrane (ILM) peeling in patients with full-thickness idiopathic macular hole (IMH) closure.

METHODS

Retrospective study on patients who underwent a vitrectomy with ILM peeling procedure. BCVA, cross-sectional OCT scans, and three-dimensional reconstructions of en face OCT scans were analysed preoperatively, at 2, 6, 12 months post-operatively. A novel image analysis technique was used to automatically measure DONFL logical properties through the radius, area, the nerve fibre layer dissociation index (NFLDI), and depth of the CMDS.

RESULTS

53 eyes of 51 patients were included, and the mean follow-up was 11.53 ± 6.26 months. CMDS was found in 46 (86.79%) eyes within 2 months after ILM peeling and 50 (94.34%) eyes within 6 months after ILM peeling. CMDS concentrated on the temporal side of the macula in all 50 eyes (100%) at first detection. The area, NFLDI, and depth of CMDS in four quadrants developed significantly during the postoperative 6 months (p < 0.05), and then these changes slowed down and remained unchanged 12 months post-operatively. The morphological changes in the temporal quadrant were significantly greater than those in other quadrants at 2, 6, 12 months (all p < 0.05) post-operatively.

CONCLUSIONS

CMDS mostly appeared and concentrated on the temporal side of the macula in IMHs within two months after ILM peeling and progressed within 6 months and remained unchanged after 12 months.

A factor for predicting simultaneous internal limiting membrane peeling during epiretinal membrane removal: swept-source optical coherence tomography-based evaluation of epiretinal membrane adhesion to the retina

PURPOSE

To investigate preoperative factors associated with simultaneous internal limiting membrane (ILM) peeling during epiretinal membrane (ERM) removal.

STUDY DESIGN

Observational cross-sectional study.

METHODS

We retrospectively reviewed 60 eyes with idiopathic ERM that underwent vitrectomy. The gap between the ERM and ILM was visualized using en face optical coherence tomography. The depth and width of the ERM-ILM gap at the initiation site of ERM removal were measured, and the relationship between preoperative factors including these parameters and simultaneous ILM peeling during ERM removal was investigated.

RESULTS

The ILM was simultaneously peeled during ERM removal in 30 eyes, but not in the other 30 eyes. Age was significantly higher (P = 0.017) and the width of the ERM-ILM gap was significantly smaller (P < 0.001) in the simultaneous ILM peeling (+) group than in the simultaneous ILM peeling (-) group. Multivariate logistic regression analysis confirmed the width of the ERM-ILM gap as a significant negative predictor for simultaneous ILM peeling (odds ratio, 0.992; 95% confidence interval, 0.986-0.997; P = 0.003). Receiver operating characteristic curve analysis of the width of the ERM-ILM gap revealed that the optimal cutoff for predicting simultaneous ILM peeling was 187.1 µm.

CONCLUSION

The small width of the ERM-ILM gap at the initiation site of ERM removal was significantly associated with simultaneous ILM peeling, indicating that the adhesion strength between the ERM and ILM at the initial ERM grasping site determines whether simultaneous ILM peeling will occur during ERM removal.

Long-term assessment of internal limiting membrane peeling for full-thickness macular hole using en face adaptive optics and conventional optical coherence tomography

OBJECTIVE

To evaluate the long-term structural and microvascular retinal effects of internal limiting membrane peeling for full-thickness macular hole (FTMH) using en face adaptive optics optical coherence tomography (AO-OCT), conventional OCT, and OCT angiography (OCTA).

DESIGN

Interventional case series.

PARTICIPANTS

Patients with FTMH treated with vitrectomy, internal limiting membrane peeling, and gas tamponade.

METHODS

Eleven eyes with FTMH that had at least 12 months of postoperative follow-up were enrolled in the study. En face AO-OCT was used to image the superficial retina in the peeled and nonpeeled areas. En face structural OCT was performed to image the inner retinal dimples (IRDs), macular thickness, and retinal nerve fibre layer (RNFL). En face OCTA was used to examine the integrity of the peripapillary nerve fibre layer (NFL) plexus.

RESULTS

AO-OCT showed RFNL wrapping around the IRDs, and no obvious peripapillary NFL plexus dropout was seen with OCTA. Scattered hyper-reflective dots were observed on the surface of the peeled retina in all patients imaged with AO-OCT. No significant differences were found in IRD number (91.5 ± 24.4 versus 77.2 ± 14.7; P = 2.07), IRD proportionate area (8.36 ± 3.34 versus 7.53 ± 2.60; P = 0.159), or macular thickness between the 6- and 12-month (or greater) postoperative visits.

CONCLUSION

IRDs do not to progress beyond 6 months postoperatively, and no obvious damage to RFNL and peripapillary NFL plexus was detected. Hyper-reflective dots on the surface of the retina suggestive of possible Müller cell reactive gliosis were identified with AO-OCT.

Dissociated Optic Nerve Fiber Layer Appearance after Macular Hole Surgery: A Randomized Controlled Trial Comparing the Temporal Inverted Internal Limiting Membrane Flap Technique with Conventional Peeling

PURPOSE

To evaluate the effect of the temporal inverted internal limiting membrane (ILM) flap technique compared with that of conventional ILM peeling on the extent of the dissociated optic nerve fiber layer (DONFL) and retinal sensitivity in patients undergoing macular hole (MH) surgery.

DESIGN

Single-center, prospective, open-label, randomized controlled clinical trial.

PARTICIPANTS

Patients requiring vitrectomy for MHs sized > 250 μm.

METHODS

Patients were randomly assigned (1:1) to 1 of the following 2 groups: (1) the control group undergoing standard ILM peeling and (2) the experimental group (flap group) undergoing the temporal inverted ILM flap technique.

MAIN OUTCOME MEASURES

The primary outcome measure was the total DONFL score at 3 months after surgery. Important secondary outcomes were microperimetry results, primary MH closure rate, external limiting membrane (ELM) and ellipsoid zone (EZ) recovery rates, and best-corrected visual acuity (BCVA).

RESULTS

Sixty-five patients were recruited between February 2018 and July 2020; primary outcome data were available for 60 patients. The median DONFL score was 7.0 (3.0-12.5) in the control group and 5.0 (1.5-8.5) in the flap group at 3 months after surgery (P = 0.145). The focal depressions characteristic of the DONFL were limited to the temporal side of the fovea in the flap group, whereas they were found all around the fovea in the control group on spectral-domain OCT images. The MH closure rate (P = 1), EZ and ELM recovery rates (P = 0.252), and BCVA (P = 0.450) were similar between the 2 groups. The 3-month overall median retinal sensitivity (MRS) (P = 0.142) and MRS improvement (P = 0.916) in the control group were comparable with those observed in the flap group. In addition, there was no significant difference between the 2 techniques when considering the temporal area (P = 0.105) or the nasal area (P = 0.468).

CONCLUSIONS

The temporal inverted ILM flap technique reduced the extent of the DONFL by preserving the nasal part of the fovea. However, the overall DONFL score was similar between the 2 techniques. In addition, the MRS and BCVA did not differ from those obtained after complete ILM peeling.

FINANCIAL DISCLOSURE(S)

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

Features of a well-timed macular hole closure related retinal regmatogenous detachment complicated by macular hole

The literature review deals with the analysis of the timing and surgical techniques of macular hole closure in patients with retinal detachment complicated by macular hole. Modern concepts of treatment tactics for this disease, its efficacy are analyzed. Benefits and drawbacks of each of the discussed surgical treatment methods are specified.

Effect of Internal Limiting Membrane Peeling or Not on Blood Flow Signal in Macular Area of Diabetic Patients with Preretinal Membrane

PURPOSE

To study the effect of intraoperative internal limiting membrane (ILM) peeling on the macular vascular structure in patients with diabetic epiretinal membrane (ERM).

METHODS

Patients with diabetic ERM were divided into an ERM + ILM peeling group (18 eyes) and an ERM peeling group (19 eyes), all of whom underwent standard vitrectomy and were followed up until 6 months postoperatively. Best-corrected visual acuity (BCVA), Central macular thickness (CMT), Vessel density (VD) and vessel length density (VLD) of the superficial as well as deep retinal capillary plexus were compared between the two groups.

RESULTS

There was no significant difference in BCVA (p = .188, .410, .901, .916) and CMT (p = .164, .128, .110, .105) between the two groups at the week 1, month 1, month 3 and month 6 after operation. In the superficial capillary plexus (SCP), the change in VD (p = .106) and VLD (p = .438) was not affected by ILM peeling, and there was no significant difference in VD (p = .154, .063, .100, .162) and VLD (p = .386, .263, .431, .391) between the two groups during the four follow-up after operation. For the deep capillary plexus (DCP), there was an effect of ILM peeling on the changes in VD (p = .024) and VLD (p = .012), ILM peeling delayed the recovery time of the VD and VLD; The VD (p = .026, .000, .003) and VLD (p = .005, .000, .000) of ERM + ILM peeling group were lower than those of ERM peeling group from the month 1 to the month 6 after operation.

CONCLUSION

Intraoperative peeling of the ILM in patients with diabetic ERM delayed the improvement of blood flow signal in the DCP but did not affect the recovery of postoperative BCVA and CMT.

PEELED INTERNAL LIMITING MEMBRANE REPOSITION FOR IDIOPATHIC MACULAR HOLES: A Pilot Randomized Controlled Trial

PURPOSE

To compare the functional and anatomical outcomes of peeled internal limiting membrane reposition and traditional internal limiting membrane peeling for the treatment of idiopathic macular hole.

METHODS

This is a randomized, single-center, and double-blinded, pilot, controlled trial.

RESULTS

Of the 30 patients enrolled, 27 (13 in Group 1 and 14 in Group 2) were included in the primary analysis (22 women [81.5%]; mean [SD] age, 61.7 [6.8] years). The BCVA was 0.23 ± 0.18 logMAR in the reposition group and 0.44 ± 0.24 logMAR in the peeling group at 6 months postoperatively (P = 0.02). The primary MH closure rate is 86.7% in the reposition group and 93.3% in the peeling group (P = 0.60). The range of the inner retinal dimpling was significantly lower in the reposition group at 6 months postoperatively (P < 0.0001). The thickness of the full parafovea (P = 0.0092), inner parafovea (P = 0.0007), inner perifovea (P = 0.0044), and outer fovea (P = 0.0392) was significantly greater in the reposition group than that in the peeling group at 6 months postoperatively. The sensitivity threshold and mfERG P1 wave amplitude density in rings one, four, and five were higher in the reposition group than in the peeling group at 6 months postoperatively.

CONCLUSION

Our findings suggest that the novel technique of peeled internal limiting membrane reposition has advantages over the traditional internal limiting membrane peeling in better microstructural outcomes of inner retina and functional recoveries. Furthermore, larger RCT studies are warranted.

Analysis of Retinal Microstructure in Eyes with Dissociated Optic Nerve Fiber Layer (DONFL) Appearance following Idiopathic Macular Hole Surgery: An Optical Coherence Tomography Study

(1) Purpose: This study aimed to evaluate morphological changes of the retina in eyes with dissociated optic nerve fiber layer (DONFL) appearance following internal limiting membrane (ILM) peeling for full-thickness idiopathic macular hole (IMH) on spectral-domain optical coherence tomography (SD-OCT). (2) Methods: We retrospectively analyzed 39 eyes of 39 patients with type 1 macular hole closure after a vitrectomy with ILM peeling procedure at a six-month minimum postoperative follow-up. The retinal thickness maps and cross-sectional OCT images were obtained from a clinical OCT device. The cross-sectional area of the retinal nerve fiber layer (RNFL) on cross-sectional OCT images was manually measured by ImageJ software. (3) Results: The inner retinal layers (IRLs) thickness thinned down much more in the temporal quadrant than in nasal quadrants at 2 and 6 months postoperatively (p < 0.001). However, the cross-sectional area of the RNFL did not change significantly at 2 and 6 months postoperatively (p > 0.05) when compared to preoperative data. In addition, the thinning of the IRL did not correlate with the best-corrected visual acuity (BCVA) at 6 months postoperatively. (4) Conclusions: The thickness of the IRL decreased in eyes with a DONFL appearance after ILM peeling for IMH. The thickness of the IRL decreased more in the temporal retina than in the nasal retina, but the change did not affect BCVA during the 6 months after surgery.

Displacement of the retina and changes in the foveal avascular zone area after internal limiting membrane peeling for epiretinal membrane

PURPOSE

We investigated the differences in displacement of the outer and inner macular retina toward the optic disc after vitrectomy with internal limiting membrane (ILM) peeling for epiretinal membrane (ERM). Foveal avascular zone (FAZ) area changes were also investigated.

STUDY DESIGN

Retrospective observational study METHODS: This retrospective observational case series included 45 eyes of 43 patients that underwent vitrectomy with ERM and ILM peeling for ERM and 38 normal eyes. The locations of the centroid of the FAZ (C-FAZ, center of the foveal inner retina) and foveal bulge (center of the foveal outer retina) were determined using 3×3mm superficial optical coherence tomography angiography. C-FAZ and foveal bulge displacements, and the pre- and postoperative FAZ areas and their associated factors, were investigated.

RESULTS

Postoperative C-FAZ dislocated significantly more toward the optic disc than in pre-operative or normal eyes (P<0.001). C-FAZ and foveal bulge displaced toward the optic disc after surgery; C-FAZ showed significantly greater displacement than foveal bulge (P<0.001). The pre- and postoperative FAZ areas were correlated (P=0.01). Preoperative FAZ areas ≧0.10mm² were reduced after surgery, and FAZ areas < 0.10mm² were increased, independent of foveal displacement.

CONCLUSION

ILM peeling during vitrectomy for ERM caused larger displacement of the inner and smaller displacement of the outer retinas, towards the optic disc. Postoperative changes in the FAZ area were dependent on the baseline FAZ area, but not on the foveal displacement. ILM may physiologically exert centrifugal tractional forces on the fovea.

A Comparison of Peel-Induced Maculopathy Following ILM Peeling Using a Microvacuum Pick Versus Forceps

OBJECTIVE

To compare peel-induced maculopathy (PIM) using surgical forceps versus the microvacuum pick (MVP).

METHODS

Consecutive eyes undergoing internal limiting membrane (ILM) peeling using either the MVP or forceps were assessed. En face optical coherence tomography (OCT) images at the level of the nerve fiber layer were generated for 6-month postoperative visit. The percentage of the imaged area showing PIM was termed the PIM index. PIM severity was additionally measured using a qualitative PIM severity scale.

RESULTS

Seventy-four consecutive eyes underwent ILM peeling with either the MVP (36/74; 49%) or forceps (38/74; 51%). At month-6 postoperatively, the mean PIM index for forceps was 7.7% vs 4.7% for the MVP (P < 0.001, R² = 0.15). At 6 months, 26/38 eyes (68.5%) in the forceps group had either moderate or severe PIM compared to 12/36 eyes (33.3%) in the MVP group (P = 0.001).

CONCLUSIONS

ILM peeling with the MVP resulted in lower PIM severity compared to forceps. [Ophthalmic Surg Lasers Imaging Retina 2023;54:37-42.].

Large Internal Limiting Membrane Tears: Prevalence, Clinical Characteristics, and Surgical Utility

PURPOSE

To describe the prevalence, clinical and imaging characteristics, and surgical utility of large internal limiting membrane (ILM) tears in eyes with epiretinal membrane (ERM).

DESIGN

Retrospective interventional case series.

METHODS

This was a single-institution study including 71 eyes of 70 consecutive patients that underwent ERM peeling by a single vitreoretinal surgeon between 2016 and 2019. Demographic and clinical data were collected from the medical record. ERMs and large ILM tears were identified and analyzed on multimodal imaging. The main outcome measures were the prevalence and characteristics of large ILM tears in eyes undergoing ERM peeling.

RESULTS

Large ILM tears were present in 23 of 71 eyes (32.4%) with ERM that underwent surgical management. A review of patients with ERM during the same period who did not undergo surgical management found large ILM tears in 8 of 100 eyes (8.0%). Large ILM tears were commonly associated with other signs of ERM-induced retinal traction, including retinal nerve fiber layer schisis in 20 of 23 eyes (87.0%), inner retinal dimpling in 8 of 23 eyes (34.8%), and discrete paravascular red lesions in 16 of 19 eyes (84.2%). In all eyes stained with brilliant blue G, the preoperative diagnosis of large ILM tear was confirmed and the scrolled ILM edge was used successfully to initiate ILM peeling.

CONCLUSIONS

Large ILM tears are often present in eyes undergoing surgery for ERM and are likely caused by ERM contracture. Careful preoperative identification of these tears is helpful for surgical planning because the scrolled flap of ILM provides a convenient and safe "handle" for initiating membrane peeling.

Extracellular Matrix: The Unexplored Aspects of Retinal Pathologies and Regeneration

Nearly a billion people worldwide are affected by vision-impairing conditions, with retinal degenerative diseases being a major cause of blindness. Unfortunately, such diseases are often permanent and progressive, resulting in further degeneration and loss of sight, due to the human retina possessing little, if any, regenerative capacity. Despite numerous efforts and great progress being made to understand the molecular mechanisms of these diseases and possible therapies, the majority of investigations focused on cell-intrinsic factors. However, the microenvironment surrounding retinal cells throughout these processes also plays an important role, though our current understanding of its involvement remains limited. Here we present a brief overview of the current state of the field of extracellular matrix studies within the retina and its potential roles in retinal diseases and potential therapeutic approaches.

Internal limiting membrane peeling in macular hole surgery

Since the era when macular hole was considered untreatable, macular hole surgery has come a long way to being one of the most successful surgeries. Internal limiting membrane (ILM) peeling has been an essential step of macular hole surgery since the establishment of the role of ILM in the aetiopathogenesis and progression of macular hole. However, the novel technique was not all virtuous. It had some vices which were not evident immediately. With the advent of spectral domain optical coherence tomography, short- and long-term effects of ILM peeling on macular structures were known; and with microperimetry, its effect on the function of macula could be evaluated. The technique has evolved with time from total peeling to inverted flap to just temporal peeling and temporal flap in an attempt to mitigate its adverse effects and to improve its surgical outcome. ILM abrasion technique and Ocriplasmin may eliminate the need of ILM peeling in selected cases, but they have their own limitations. We here discuss the role of ILM in the pathogenesis of macular hole, the benefits and adverse effects of ILM peeling, and the various modifications of the procedure, to then explore the alternatives.

Vitrectomy with internal limiting membrane peeling and gas tamponade for myopic foveoschisis

Background

We evaluated the effect of vitrectomy with internal limiting membrane (ILM) peeling and gas tamponade for myopic foveoschisis (MF), and analysed prognosis with different gas tamponade.

Methods

Retrospective, non-randomized study. The records of patients with MF treated by vitrectomy, were reviewed. Patients were followed up postoperatively mean 16.74 months, to record changes of Best-corrected visual acuity (BCVA) and central foveal thickness (CFT).

Results

Sixty-two eyes (59 patients) were analysed in total, with mean age of 55.29 ± 10.34 years, 49 females (83.1%). Foveoschisis completely resolved in all eyes at least 6 months post vitrectomy, except for two postoperative full-thickness macular holes (FTMH). Final BCVA improved significantly from 0.69 ± 0.39 to 0.44 ± 0.42 logMAR, and CFT from 502.47 ± 164.78 to 132.67 ± 52.26 μm. Patients were subdivided into three subgroups based on the different endotamponades used (C3F8, C2F6, and air). Baseline BCVA, baseline CFT and foveal detachment (FD) were not significantly different among the three groups. Eyes treated with air tamponade had better visual outcomes than eyes with C3F8 tamponade (P = 0.008). Baseline BCVA and FD were significant risk factors for postoperative BCVA (P < 0.001 and P = 0.013, respectively).

Conclusions

Vitrectomy with ILM peeling and gas tamponade results in good functional and anatomic outcomes in the treatment of most MF. Good vision and no-FD pre-surgery are related with good visual prognosis. Air tamponade can provide as good visual recovery as expansive gas, and reduce postoperative complications.

Spotlight on the Internal Limiting Membrane Technique for Macular Holes: Current Perspectives

Pars plana vitrectomy has become the standard procedure for primary macular holes (MHs) repair, including the removal of the posterior cortical vitreous, the stripping of eventual epiretinal membranes, and finally an intraocular gas tamponade. During this procedure, peeling the internal limiting membrane (ILM) has been proven to increase closure rates and avoid postoperative reopening in several researches. In fact, even in large MHs more than 400 µm, the advantage of peeling off the ILM was highlighted by better anatomical closure rates. Nevertheless, some authors suggested that ILM peeling is not always essential, because it generates various side effects in retinal structure and function. Furthermore, the ideal amount of ILM peeling and the most effective strategies for removing the ILM are still subject of research. Different surgical modifications have been reported as alternatives to traditional peeling in certain clinical settings, including ILM flaps, ILM scraping, and foveal sparing ILM peeling. As regards large MHs, the introduction of ILM inverted flap appeared as a game changer, offering a significantly higher >90% closure rate when compared to traditional ILM peeling. Modifications to inverted ILM flap procedures have been claimed in recent years, in order to define the best area and direction of ILM peeling and its correlation with functional outcomes. Moreover, several innovations saw the light in the setting of recurrent MHs, such as ILM free flap transposition, inverted ILM flap combined autologous blood clot technique, neurosensory retinal flap, and human amniotic membrane (HAM) plug, claiming higher anatomical success rate also in those complex settings. In conclusion, the aim of this review is to report how the success rate of contemporary macular surgery has grown since the turn of the century, especially for big and chronic MHs, analyzing in which way ILM management became a crucial point of this kind of surgery.

Epiretinal Membrane Surgery Using Intraoperative OCT-Guided Membrane Removal in the DISCOVER Study versus Conventional Membrane Removal

PURPOSE

To provide a comparative assessment of clinical outcomes between patients undergoing intraoperative OCT (iOCT) and conventional surgery for pars plana vitrectomy (PPV) with epiretinal membrane (ERM) peel.

DESIGN

Case-control retrospective, comparative assessment.

PARTICIPANTS

Patients undergoing PPV with membrane peel for ERM with eyes pooled from the prospective Determination of Feasibility of Intraoperative Spectral Domain Microscope Combined/Integrated OCT Visualization During En Face Retinal and Ophthalmic Surgery (DISCOVER) iOCT study and eyes undergoing conventional ERM surgery without iOCT.

METHODS

Visual acuity and OCT assessment before ERM surgery and at 1-, 3-, 6-, and 12-month follow-up after standard small-gauge PPV with iOCT feedback (iOCT DISCOVER group) or PPV with compulsory internal limiting membrane (ILM) peeling (conventional group). Visual acuity, central subfield thickness (CST), reoperation rate, and ERM recurrence were determined by record review and post hoc assessment of clinical OCTs after ERM peel.

MAIN OUTCOME MEASURES

Visual acuity and ERM recurrence.

RESULTS

A total of 262 eyes were included. Visual acuity (VA) improved 11.9 letters in the iOCT group (P < 0.0001) and 12.1 letters in the conventional group (P < 0.0001) at 12 months after ERM surgery. Visual acuity improvement did not differ between the iOCT and conventional groups at 1, 3, 6, or 12 months after surgery (P > 0.05 for each time point). Preoperative mean CST decreased in the iOCT group (P < 0.0001) and conventional group (P < 0.0001) with no difference between groups in CST reduction at 12 months (P = 0.36). No reoperations or visually significant recurrent ERMs occurred in either cohort.

CONCLUSIONS

Intraoperative OCT-guided ERM removal without mandated ILM peeling provided similar VA and anatomic results to conventional ILM peeling for ERM. Future randomized prospective studies are needed to assess fully the possible role of iOCT in ERM surgery and to evaluate the potential impact of nonfoveal ERM persistence or recurrence in comparison with conventional surgery.

Long-Term Observations of Thickness Changes of Each Retinal Layer following Macular Hole Surgery

Purpose

To determine the long-term changes of the thickness of each retinal layer following macular hole (MH) surgery combined with internal limiting membrane (ILM) peeling.

Method

The medical records of 42 eyes of 42 patients (41 to 86 years of age) who underwent MH surgery with ILM peeling between February 2016 and October 2018 were reviewed. A single surgeon operated on all patients, and all were followed for at least 24 months postoperatively. Spectral-domain optical coherence tomography (OCT) was performed to obtain retinal thickness maps of the parafoveal region corresponding approximately to the ILM peeled area. Each retinal layer was automatically segmented by the embedded software, and thickness maps were constructed for the total retinal layer (TRL), inner RL (IRL), middle RL (MRL), and outer RL (ORL). The averaged value of each retinal layer thickness was analyzed in the temporal/upper, temporal/lower, nasal/upper, and nasal lower quadrants.

Results

The TRL thickness was significantly decreased in the temporal areas postoperatively. The IRL thickness thinned progressively and significantly until 6 months without further thinning in the temporal quadrants. The MRL thickness of all areas was significantly thicker than the baseline values at 0.5 months and then gradually decreased in the temporal regions. However, the thickening in the nasal regions returned to the baseline values after 1.5 months. The ORL decreased transiently relative to the baseline values at 0.5 months in all areas.

Conclusions

The ILM peeling does not affect only the thickness of the inner retina but also the middle and outer retinae in the parafoveal region. The chronological changes of the thickness after surgeries varied among the retinal layers and macular regions.

Effect of internal limiting membrane peeling on postoperative visual acuity in macula-off rhegmatogenous retinal detachment

PURPOSE

To investigate the effects of internal limiting membrane (ILM) peeling on visual acuity (VA) after rhegmatogenous retinal detachment (RRD) surgery.

METHODS

This retrospective analysis examined the medical records of patients with RRD who underwent vitrectomy at 26 institutions. To detect prognostic factors of VA at 6 months postoperatively (post-VA), multivariate linear regression was performed with post-VA as the objective variable; ILM peeling, sex, age, preoperative VA (pre-VA), intraocular pressure, axial length, duration of RRD, and cataract surgery served as explanatory variables. Recurrence of RRD and epiretinal membrane formation within 6 months postoperatively were compared between groups of patients with and without ILM peeling, among patients with macula-on and macula-off RRD.

RESULTS

The inclusion criteria were met by 523 eyes with a macula-on RRD and 364 eyes with a macula-off RRD. ILM peeling was performed in 85 eyes with a macula-on RRD and 57 eyes with a macula-off RRD. In eyes with a macula-on RRD, ILM peeling did not affect post-VA (p = 0.72). Vitrectomy without cataract surgery and poor pre-VA were significantly associated with poor post-VA (p = 0.01 and p < 0.001, respectively). In eyes with a macula-off RRD, ILM peeling, long duration of RRD, and poor pre-VA were significantly associated with poor post-VA (p = 0.037, p = 0.007, and p < 0.001, respectively). Recurrence of RRD and epiretinal membrane formation were similar between groups of patients with and without ILM peeling, among patients with macula-on and macula-off RRD. Retina sensitivity was not evaluated by microperimetry.

CONCLUSION

ILM peeling did not affect post-VA in eyes with a macula-on RRD, whereas post-VA was worse in eyes with ILM peeling than in eyes without peeling, among eyes with a macula-off RRD.

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.

MACULAR SENSITIVITY IN THE AREA OF INTERNAL LIMITING MEMBRANE PEELING IN EYES AFTER PARS PLANA VITRECTOMY WITH THE TEMPORAL INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE FOR A FULL-THICKNESS MACULAR HOLE

PURPOSE

To examine the relationship between retinal sensitivity and the area of internal limiting membrane (ILM) peeling during pars plana vitrectomy for a full-thickness macular hole.

METHODS

Twenty-four eyes a minimum of 6 months after temporal inverted flap pars plana vitrectomy for a full-thickness macular hole were included in the study. En face spectral-domain optical coherence tomography images were used to assess margins of the peeled ILM area. Microperimetry was performed to examine retinal sensitivity within the central 10°. Areas of peeled ILM in en face optical coherence tomography images were correlated with the average sensitivity threshold. Retinal sensitivities at the location of each measurement point were compared with structural abnormalities observed in en face spectral-domain optical coherence tomography images.

RESULTS

The mean retinal sensitivity in the area of ILM removal was significantly lower compared with the area of preserved ILM (24.29 ± 3.96 dB vs. 26.19 ± 2.10 dB, P < 0.0001, respectively). The peeled ILM area showed a negative correlation with the average sensitivity threshold (r = -0.56, P < 0.01).

CONCLUSION

A larger area of ILM peeling during temporal inverted flap pars plana vitrectomy for a full-thickness macular hole is related to lower retinal sensitivity in the central macula.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS BEFORE AND AFTER VITRECTOMY FOR MACULAR HOLES: Useful or Useless?

PURPOSE

To investigate the vascular remodeling of optical coherence tomography angiography in full-thickness macular hole surgery.

METHODS

This retrospective, observational case series included 33 eyes of 33 patients with a full-thickness macular hole who underwent epiretinal membrane removal. Data were collected on best-corrected visual acuity, structural B-scan optical coherence tomography, and optical coherence tomography angiography preoperatively and at 1, 3, and 6 months postoperatively. Optical coherence tomography angiography was used to assess the retinal vascular density (VD) of the superficial vascular plexus and deep vascular plexus (DVP). Vascular density was assessed using the Early Treatment Diabetic Retinopathy Study grid for the whole, inner, and outer grids.

RESULTS

A statistically significant correlation was found between the VD (whole, inner, and outer grids) of the superficial vascular plexus alone from baseline to 1-month postoperatively (P < 0.001). Similarly, VD was correlated from baseline to 1, 3, and 6 months postoperatively to the whole (P < 0.0005, F = 23.22), inner (P < 0.0005, F = 28.23), and outer Early Treatment Diabetic Retinopathy Study grids of DVP (P = 0.033, F = 3.49). The best-corrected visual acuity and VD were significantly correlated with the superficial vascular plexus and DVP at baseline and 6 months (P < 0.05, all correlations). The most significant correlation was observed at 6 months between best-corrected visual acuity and DVP in the whole, inner, and outer Early Treatment Diabetic Retinopathy Study grids (P < 0.001).

CONCLUSION

Superficial vascular plexus and DVP are affected by full-thickness macular holes, with the most significant effects being on the DVP. Full-thickness macular hole surgery leads to an improvement in the best-corrected visual acuity in many eyes and the restoration of the VD, especially of the DVP.

Tomographic Structural Changes of the Inner Retina after Internal Limiting Membrane Peeling for Idiopathic Epiretinal Membrane

Purpose

To investigate the tomographic structural changes in the retinal layers after internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (ERM).

Methods

Sixty-nine eyes treated with vitrectomy and ILM peeling for idiopathic ERM were analyzed. Parafoveal retinal thickness was measured at baseline and 6 months after surgery.

Results

Total retinal thickness decreased significantly in the nasal and temporal subfields after surgery (p < 0.001), whereas the inner nuclear layer and outer nuclear layer showed nasal thickening (all, p < 0.001). The postoperative temporal/nasal subfield thickness ratio of each layer was significantly lower than that of fellow eyes. Eyes with larger ILM peeling showed a significantly lower temporal/nasal subfield thickness ratio (p = 0.033) than those with smaller sizes.

Conclusions

The retinal thickness of each layer showed anatomical changes from ILM peeling and ERM removal. Nasal parafoveal thickening and temporal thinning occurred in the inner retinal architecture, which might be affected by ILM peeling size.

FOVEA-SPARING VERSUS COMPLETE INTERNAL LIMITING MEMBRANE PEELING IN VITRECTOMY FOR THE TREATMENT OF MACULAR HOLES

PURPOSE

To compare the anatomical and functional outcomes of vitrectomy involving complete internal limiting membrane peeling (CP) with those of vitrectomy involving fovea-sparing internal limiting membrane peeling (FSP) for the treatment of macular holes measuring >250 µm.

METHODS

This prospective, randomized, comparative study included 46 eyes with a medium or large macular hole that was randomized to undergo complete (CP group) or fovea-sparing (FSP group) internal limiting membrane peeling during vitrectomy. The main outcome measures included the foveal retinal sensitivity, visual acuity, and central retinal thickness.

RESULTS

Both groups showed significantly improved foveal retinal sensitivity after surgery; the mean foveal retinal sensitivity change at 12 months after surgery was +2.8 ± 2.1 dB in the CP group and +7.2 ± 2.3 dB in the FSP group. The visual acuity also showed a significant improvement in both groups, with no significant differences in values at any time point. Regarding central retinal thickness, there was a significant decrease in the CP group and no change in the FSP group. Nicks or dimples in the inner retinal layers were visible in the fovea and perifovea of nine eyes in the CP group.

CONCLUSION

Our findings suggest that both CP and FSP are safe and effective treatments leading to functional and anatomical improvements in patients with all size macular holes. However, the fovea-sparing technique may provide better functional outcomes because of a greater improvement in foveal retinal sensitivity.

INTERNAL LIMITING MEMBRANE PEELING VERSUS NONPEELING TO PREVENT EPIRETINAL MEMBRANE DEVELOPMENT IN PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT: A Swept-Source Optical Coherence Tomography Study With a New Postoperative Classification System

PURPOSE

To determine whether internal limiting membrane peeling in primary rhegmatogenous retinal detachment prevents epiretinal membrane (ERM) development. Secondarily, we propose a classification system for postoperative ERMs.

METHODS

Retrospective, interventional, comparative case series. Consecutive eyes with primary rhegmatogenous retinal detachment (n = 140) treated by a single surgeon. The presence of postoperative ERMs was assessed with swept-source optical coherence tomography.

RESULTS

An ERM was detected in 26 eyes (46.4%) in the nonpeeling group and in one eye (1.8%) in the internal limiting membrane peeling group (P ≤ 0.001). The median visual acuity significantly improved in both groups (P ≤ 0.001). Inner retinal dimples were observed in 41.1% of eyes in the internal limiting membrane peeling group versus 0% in the nonpeeling group (P ≤ 0.001), and they were not correlated with visual acuity (r = 0.011; P = 0.941). Based on swept-source optical coherence tomography findings, we identified three different types of ERMs: 7 (26.9%) were classified as Type 1, 12 (46.1%) as Type 2, and 7 (26.9%) as Type 3. Superficial retinal plexus deformations observed on optical coherence tomography angiography and en face images were detected in 100% of Type 3 ERMs, 41.6% of Type 2, and 0% of Type 1 (χ = 14.3; P = 0.001). Interestingly, all of the patients who presented these alterations also had metamorphopsia.

CONCLUSION

Internal limiting membrane peeling in primary rhegmatogenous retinal detachment seems to prevent postoperative ERM development. Swept-source optical coherence tomography analysis is helpful to define and classify different types of ERMs and to establish the surgical indication for their removal.

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.

Changes in the Ganglion Cell Complex after Inner Limiting Membrane Peeling for Epiretinal Membrane in Glaucoma Patients

BACKGROUND

Epiretinal membrane (ERM) is a disease that affects the vitreoretinal interface and causes metamorphopsia, anorthopia, and decreased visual acuity. In this study, ERM patients who underwent internal limiting membrane (ILM) peeling were classified as those with glaucoma (Group G) and a control group (Group C). Changes in ganglion cell complex (GCC) thickness were compared between these groups to investigate whether such changes had an effect on progression of glaucoma from structural change.

METHODS

This was a retrospective, observational study that included 27 eyes of 27 patients. Group C included 22 eyes, and Group G included 5 eyes. Patients underwent ILM peeling, and cataract surgery was combined with vitrectomy for 16 phakic eyes; 2 phakic eyes and 9 aphakic eyes were treated only with vitrectomy. GCC thickness was measured preoperatively and at 2 weeks and 1, 3, and 6 months postoperatively, and these values and the rates of thinning were compared between the two groups.

RESULTS

The mean age of patients was 66.7±12.8 years (range 30-84 years). There was no significant difference between groups in the thickness of the GCC or its rate of thinning after ILM peeling.

CONCLUSIONS

The present results suggest that this procedure does not cause structural exacerbation of glaucoma in glaucoma patients. Although further studies of the functional effects of ILM peeling are required, the present results suggest that there is no significant difference between the two groups.

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.

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.

VALIDITY AND EFFICACY OF INTERNAL LIMITING MEMBRANE PEELING DURING INITIAL VITRECTOMY FOR RHEGMATOGENOUS RETINAL DETACHMENT: VISUAL OUTCOMES IN MACULA-SPARING CASES

PURPOSE

To compare the visual outcomes and prevalence of epiretinal membrane (ERM) growth postoperatively between eyes treated with and without internal limiting membrane peeling during vitrectomy for macula-sparing rhegmatogenous retinal detachment.

METHODS

Fifty-five consecutive cases who underwent vitrectomy for macula-sparing rhegmatogenous retinal detachment were reviewed retrospectively. The inclusion criteria were a minimal 6-month follow-up postoperatively and spectral domain optical coherence tomographic images available at follow-up. Cases with any pre-existing macular condition possibly affecting the visual prognosis were excluded. All cases were divided into two groups: 22 cases without internal limiting membrane peeling (Group 1) and 33 cases with internal limiting membrane peeling (Group 2). The two groups were compared using the Mann-Whitney U test and Fisher exact test in terms of the best-corrected visual acuity (BCVA) (logarithm of the minimum angle of resolution) before vitrectomy, postoperative BCVA, and the presence of postoperative ERM growth. Postoperative BCVA and ERM growth were determined at 6 months, 12 months, and the last visit. The visual outcomes were also analyzed between cases with and without postoperative symptomatic ERM growth, which caused visual impairment and required surgical removal.

RESULTS

The mean postoperative BCVAs were 0.00, -0.08, and -0.08 logarithm of the minimum angle of resolution in Group 1, and -0.08, -0.08, and -0.08 logarithm of the minimum angle of resolution in Group 2 at 6 months, 12 months, and the last visit, respectively, and did not differ significantly between the 2 groups at each time point except for at 12 months (P = 0.027). An ERM developed in 14 cases in Group 1, 7 of which were symptomatic. No cases in Group 2 had ERM growth. The prevalence of ERM growth was significantly (P < 0.001) higher in Group 1 than Group 2. The BCVA was significantly worse at 6 months (P = 0.011), 12 months (P = 0.003), and the last visit (P = 0.019) in 7 cases with symptomatic ERMs (median, 0.30, 0.15, and 0.10 logarithm of the minimum angle of resolution, respectively) than in 48 cases without symptomatic ERMs (median, -0.08, -0.08, and -0.08 logarithm of the minimum angle of resolution, respectively).

CONCLUSION

Internal limiting membrane peeling did not result in decreased visual acuity postoperatively in cases with a macula-sparing rhegmatogenous retinal detachment, and the procedure significantly prevented postsurgical ERM growth. Symptomatic ERMs led to decreased visual acuity even after surgical removal. These results support the validity and efficacy of internal limiting membrane peeling for preventing ERM growth after rhegmatogenous retinal detachment repair.

Involvement of Anoikis in Dissociated Optic Nerve Fiber Layer Appearance

Dissociated optic nerve fiber layer (DONFL) appearance is characterized by dimpling of the fundus when observed after vitrectomy with the internal limiting membrane (ILM) peeling in macular diseases. However, the cause of DONFL remains largely unknown. Optical coherence tomography (OCT) findings have indicated that the nerve fiber layer (NFL) and ganglion cells are likely to have been damaged in patients with DONFL appearance. Since DONFL appearance occurs at a certain postoperative period, it is unlikely to be retinal damage directly caused by ILM peeling because apoptosis occurs at a certain period after tissue damage and/or injury. However, it may be due to ILM peeling-induced apoptosis in the retinal tissue. Anoikis is a type of apoptosis that occurs in anchorage-dependent cells upon detachment of those cells from the surrounding extracellular matrix (i.e., the loss of cell anchorage). The anoikis-related proteins βA3/A1 crystallin and E-cadherin are reportedly expressed in retinal ganglion cells. Thus, we theorize that one possible cause of DONFL appearance is ILM peeling-induced anoikis in retinal ganglion cells.

Surgical Treatment of Idiopathic Macular Hole Using Different Types of Tamponades and Different Postoperative Positioning Regimens

Purpose

To compare the effect of different types of intraocular tamponade and different types of postoperative positioning on the closure of idiopathic macular hole (IMH).

Methods

Prospective randomized clinical trial enrolling 104 eyes of 100 patients (age, 57–87 years) undergoing MH surgery. All patients were operated on by an experienced surgeon using 25-gauge pars plana vitrectomy (PPV) and internal limiting membrane (ILM) peeling. Patients were randomized according to the type of intraocular tamponade and postoperative positioning into the following four groups: SF6 + nonsupine reading position (n = 26) (group 1), air + nonsupine reading position (n = 25) (group 2), air + prone position (n = 26) (group 3), or SF6 + prone position (n = 27) (group 4). The follow-up period was 6 months.

Results

MH closure was achieved in 87 eyes (83.7 %) in the overall sample after the first surgery, with closure rates of 100%, 56%, 84.6%, and 92.6% in groups 1, 2, 3, and 4, respectively. The group 2 was significantly less successful compared to the other three groups (p < 0.05). MH of sizes ≤400 µm was closed in 97.2% of cases after the first surgery, with no significant differences between groups (p = 0.219). MH with sizes over 400 µm was closed in 70.9% of cases after the first surgery, with both groups with air tamponade being significantly less successful than group 1. The nonsupine reading position was subjected to a better subjective evaluation in terms of postoperative comfort and quality of sleep, with no differences between air and SF6 tamponade tolerance.

Conclusion

PPV with ILM peeling, intraocular tamponade, and positioning remains the basic surgical approach in the treatment of IMH. For MH ≤ 400 µm, a high closure rate can be achieved by combining air tamponade and nonsupine reading position. For macular holes >400 µm, the greatest anatomical success can be achieved by using the SF6 tamponade in combination with the nonsupine reading position.

Long-term follow up of en face optical coherence tomography of the inner retinal surface following internal limiting membrane peeling for idiopathic macular holes

PURPOSE

To evaluate sequential changes in the inner retinal surface using en face spectral domain optical coherence tomography (SD-OCT) following internal limiting membrane (ILM) peeling for idiopathic full thickness macular holes.

METHODS

Retrospective, interventional study on 45 eyes of 42 patients with type 1 macular hole closure after a single procedure and a minimum post-operative follow up of 6 months. Best corrected visual acuity (BCVA), fundus photographs, B scan and en face SD-OCT scans were analysed pre-operatively, at 2, 6, 12 months post-operatively and then yearly. The presence or absence of concentric macular dark spots (CMDS) on the ILM slab of en face SD-OCT, their distribution pattern and course in terms of number and size of the dark spots was qualitatively assessed at each follow up.

RESULTS

CMDS was identified in a total of 26 eyes (57.78%). Of these, it was detected in 21 eyes at 2 months and the remaining by 6 months. At the time of first detection, the distribution was classified as type 1 in 9 eyes (35%), type 2 in 7 eyes (27%) and type 3 in 10 eyes (38%). There was apparent increase in the number and size of the CMDS in 16 eyes (62%) no later than 12 months follow up, while 10 eyes (38%) remained stable. There was no decrease or resolution noted in any patient. The mean post-operative follow up was 19.4 months (range 6-69 months).

CONCLUSION

Inner retinal defects in the form of CMDS can be picked up on en face SD-OCT between 2-6 months post-operatively. They remain stable or become more prominent upto 12 months follow up, but do not regress once present. En face SD-OCT is recommended in all cases where ILM is peeled to assess CMDS.

En Face Image-Based Analysis of Epiretinal Membrane Formation after Surgery for Idiopathic Epiretinal Membrane

PURPOSE

To analyze en face epiretinal membrane (ERM) images constructed using swept-source (SS) OCT and to determine the incidence of ERM formation after ERM surgery and its effects on visual function.

DESIGN

Retrospective, consecutive observational study.

PARTICIPANTS

Consecutive series of 73 eyes (71 patients) with idiopathic ERM that underwent vitrectomy with both ERM and internal limiting membrane (ILM) peeling.

METHODS

We retrospectively reviewed the data of the 73 eyes included in the study. During surgery, the ERM was removed as extensively as possible, and the ILM was removed such that the area of ILM peeling was at least larger than the parafoveal area. All patients underwent comprehensive ophthalmologic examinations, including assessments of best-corrected visual acuity and metamorphopsia, before and at 2 weeks and 6 months after the surgery. En face images constructed using SS OCT were used to investigate ERM formation.

MAIN OUTCOME MEASURES

The incidence of ERM formation at 6 months after the surgery, effects of ERM formation on visual function, and the relationship between ERM formation and the extent of ERM and ILM peeling.

RESULTS

At 6 months after ERM and ILM peeling, 8 eyes (11.0%) showed ERM formation (formation group). Twenty eyes (27.4%) exhibited remnant ERM without ERM formation (remnant group), whereas 45 eyes (61.6%) showed no ERM (no ERM group). In both the remnant and no ERM groups, best-corrected visual acuity and metamorphopsia showed significant improvements after ERM surgery (both P < 0.01); these improvements were not seen in the formation group (P = 0.067 and P = 0.053, respectively). However, no significant differences were found in preoperative and postoperative best-corrected visual acuities and metamorphopsia among the 3 groups. In the formation group, ERM formation occurred only in the area with residual ILM. Most patients who underwent ILM peeling in which the area of the peeling covered the ERM belonged to the no ERM group (97.7%; P < 0.01).

CONCLUSIONS

Epiretinal membrane formation does not affect visual function significantly when the area of ILM peeling is larger than the parafoveal area. When the ILM peeling area covers the ERM area, postoperative ERM formation can be prevented.

Rates of Reoperation in 10 114 Patients with Epiretinal Membranes Treated by Vitrectomy with or without Inner Limiting Membrane Peeling

PURPOSE

To compare rates of reoperation in patients with idiopathic epiretinal membrane (ERM) who received pars plana vitrectomy (PPV) with or without inner limiting membrane (ILM) peeling and to assess trends in the overall use of ILM peeling over time.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients included in the IBM Marketscan database between January 1, 2008, and December 31, 2016, who underwent surgery for idiopathic ERM.

METHODS

Procedure claims with laterality codes were used to determine patients with idiopathic ERM who received PPV with or without ILM peel between 2008 and 2016, and to identify cases of reoperation and subsequent retinal detachment within 1 year of index surgery.

MAIN OUTCOME MEASURES

The primary outcome was rate of reoperation for recurrent ERM according to whether or not patients receive an ILM peel during their index ERM surgery. We also assessed trends for index ERM surgery (ILM peel or no ILM peel) between 2008 and 2016, and the risk of developing retinal detachment within 1 year of the index ERM surgery.

RESULTS

A total of 10 114 patients received ERM surgery and met inclusion criteria (5310 without ILM peel and 4804 with ILM peel). The reoperation rate was significantly lower among patients who received PPV with ILM peel (0.88%) compared with patients without ILM peel (1.48%; P = 0.007). In 2008, PPV without ILM peel represented 70% of ERM procedures, but PPV with ILM peeling accounted for 52% and 70% of ERM procedures in 2013 (P < 0.001) and 2016 (P < 0.001), respectively. The rates of retinal detachment were similar between patients who received an ILM peel (0.79%) and patients who did not receive an ILM peel (0.92%) during their primary ERM surgery (P = 0.474).

CONCLUSIONS

The increasing use of PPV with ILM peeling to address ERM removal is associated with significantly reduced reoperation rates within 1 year. Future studies are needed to determine the cost-effectiveness of performing an ILM peel for initial idiopathic ERM repairs and evaluate long-term visual and structural changes related to ILM peeling.