INTERNAL LIMITING MEMBRANE PEELING-DEPENDENT RETINAL STRUCTURAL CHANGES AFTER VITRECTOMY IN RHEGMATOGENOUS RETINAL DETACHMENT

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.

Intraocular kinetics of pathological ATP after photoreceptor damage in rhegmatogenous retinal detachment

PURPOSE

Extracellular Adenosine triphosphate (ATP) released by dying cells may cause a secondary cell death in neighboring cells in retinal degeneration. We investigated intraocular ATP kinetics to gain mechanical insights into the pathology in rhegmatogenous retinal detachment (RRD).

STUDY DESIGN

Retrospective clinical study.

METHODS

Vitreous or subretinal fluids (SRF) were obtained from patients with RRD (n=75), macular hole (MH; n=20), and epiretinal membrane (ERM; n=35) during vitrectomy. ATP levels in those samples were measured by luciferase assay.

RESULTS

Mean ATP levels in the vitreous from RRD patients were significantly higher compared to those from MH and ERM patients (2.3 and 0.3 nM, respectively. P<0.01). Mean ATP levels in the SRF from RRD (11.7 nM) were higher than those in the vitreous from RRD (P<0.01). Mean ATP levels in the vitreous with short durations (1-8 days) of RRD were higher compared to those with long durations (>8 days) (3.2 and 1.4 nM, respectively. P<0.05). Similarly, ATP in SRF with short durations were higher than those with long durations (23.8 and 3.6 nM, respectively. P<0.05). Furthermore, the concentrations of ectonucleoside triphosphate diphosphohydrolase-1 (ENTPD1), a major ATP degradative enzyme, in the vitreous from RRD were higher than those from MH/ERM (1.2 and 0.2 ng/ml, respectively. P<0.01). ENTPD1 expression was localized in the cytoplasm of CD11b-positive infiltrating cells in the vitreous and retinal cells.

CONCLUSION

ATP increased in the vitreous and SRF in RRD and decreased over time with an upregulation of ENTPD1. The kinetics indicate the pathological mechanism of the excessive extracellular ATP after RRD.

Selective internal limiting membrane peeling for prevention of secondary epiretinal membrane after vitrectomy for rhegmatogenous retinal detachment

PURPOSE

We introduce selective internal limiting membrane (ILM) peeling, a guideline procedure to determine whether to remove the ILM during vitrectomy for rhegmatogenous retinal detachment (RRD).

STUDY DESIGN

Retrospective case series METHODS: Patients who underwent pars plana vitrectomy for RRD and were followed up for 12 months or longer were included. When vitreous cortex remnants (VCRs) were detected with triamcinolone acetonide, the ILM was removed; otherwise, the ILM was preserved ("selective ILM peeling"). The factors associated with the presence of VCRs and incidence of secondary epiretinal membrane (ERM) were analyzed.

RESULTS

VCRs were detected in 87 of 133 eyes (65.4%) in which the ILM was removed. Younger age, better preoperative visual acuity, and vitreous hemorrhage were negatively correlated with the presence of VCRs. No ERM occurred in the eyes after ILM peeling. Among the eyes with ILM preservation, subclinical ERM was noticed in 4 eyes (8.7%), and 1 eye (2.1%) required additional surgery owing to ERM. ERM occurred more commonly in eyes with the ILM preserved (P = .004). However, no differences in the rate of additional surgeries were found between the 2 groups.

CONCLUSION

Selective ILM peeling offers an alternative option to reduce the burden of ILM peeling or additional surgery.

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.

Injectable in situ cross-linking hyaluronan hydrogel for easier removal of posterior vitreous cortex in vitrectomy

PURPOSE

Removing transparent vitreous tissues, such as a residual vitreous cortex (VC) or proliferative membrane, without damaging the retina is often problematic in vitrectomy. We examined the feasibility of an injectable in situ cross-linking hyaluronan hydrogel (XL-HA) for vitrectomy.

STUDY DESIGN

Experiments using ex vivo and in vivo animal models.

METHODS

HA-dibenzocyclooctyne and HA-azidoethylamine solutions were mixed to form XL-HA, which then gradually formed a hydrogel. We tested the function of XL-HA in ex vivo porcine eyes. We then examined the performance of XL-HA in in vivo rabbit models of posterior vitreous detachment, posterior VC removal, and proliferative vitreoretinopathy.

RESULTS

The ex vivo study showed that XL-HA rapidly embedded triamcinolone acetonide, mimicking VC attached to the retina, and became hard enough to be pinched with tweezers within 3 minutes, allowing us to remove only the triamcinolone acetonide without impairing the internal limiting membrane. In the in vivo rabbit models, XL-HA injection improved posterior vitreous detachment, and the thin and fragile posterior VC or fibrous proliferative membrane was readily peeled off without any damage to the underlying retina as compared with untreated controls. A short-term intraocular biocompatibility test demonstrated that the intraocular pressure remained normal with XL-HA injected into the eye. In addition, transmission electron microscopy showed no obvious abnormalities in the cornea or in the inner and outer retina.

CONCLUSION

The results indicate that XL-HA is a potential adjunctive device to help make vitrectomy safe, effective, and successful.

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.

Primary ILM peeling during retinal detachment repair: a systematic review and meta-analysis

Epiretinal membrane (ERM) formation is a known postoperative complication following retinal detachment (RD) repair surgery. Prophylactic peeling of the internal limiting membrane (ILM) during surgery has been shown to reduce the risk of developing postoperative ERM formation. Some baseline characteristics and degrees of surgical complexity may act as risk factors for ERM development. In this review we aimed to investigate the benefit of ILM peeling in patients without significant proliferative vitreoretinopathy (PVR) who underwent pars plana vitrectomy for RD repair. A literature search using PubMed and various keywords retrieved relevant papers from which data were extracted and analyzed. Finally, the results of 12 observational studies (3420 eyes) were summarized. ILM peeling significantly reduced the risk of postoperative ERM formation (RR = 0.12, 95% CI 0.05-0.28). The groups did not differ in final visual acuity (SMD 0.14 logMAR (95% CI - 0.03-0.31)). The risk of RD recurrence (RR = 0.51, 95% CI 0.28-0.94) and the need for secondary ERM surgery (RR = 0.05, 95% CI 0.02-0.17) were also higher in the non-ILM peeling groups. In summary, although prophylactic ILM peeling appears to reduce the rate of postoperative ERM, this benefit does not translate into consistent visual recovery across studies and potential complications must be considered.

Optical Coherence Tomography Findings in Rhegmatogenous Retinal Detachment: A Systematic Review

Rhegmatogenous retinal detachment is a sight-threatening condition that may lead to blindness if left untreated. Surgical treatments may vary and are tailored to a single patient. Anatomical and functional results may vary, due to factors that are currently under study. Optical coherence tomography (OCT) allows a detailed visualization of the retinal structure. Some studies have been performed using OCT on eyes with retinal detachment. We performed a review on the subject. Several data have been obtained using different OCT applications. Some alterations may represent potential biomarkers since they are associated with visual and anatomical prognoses. Increased knowledge on the subject may be helpful to choose among different surgical strategies and endotamponades. More research on the topic is needed.

Temporal retinal thinning might be an early diagnostic indicator in male pediatric X-linked Alport syndrome

AIM

To evaluate temporal retinal thinning changes in retinal layers using spectral-domain optical coherence tomography (SD-OCT) in pediatric X-linked Alport syndrome (XLAS) patients.

METHODS

A retrospective case-control study. SD-OCT scans of pediatric patients diagnosed with XLAS and age- and sex-matched healthy control participants were reviewed. Automated segmentation of SD-OCT scans was induced to analyze the retinal thickness (RT) of different layers. The temporal thinning index (TTI) was calculated for each layer and compared between the patients and the control group.

RESULTS

Forty-three pediatric XLAS patients and 60 healthy controls were included. Temporal retinal thinning was present in 33 patients (76.74%), while 28 patients (65.11%) had severe pathological temporal retinal thinning and 5 patients (11.63%) had moderate thinning. The temporal inner sector RT (P<0.0001), the temporal outer sector RT (P<0.0001), and the nasal outer sector RT (P=0.0211) were significantly thinner in the XLAS male patients. The TTI of the total retina was significantly higher in the XLAS group than in the control group (P<0.0001). The TTI of the inner retina layers (P<0.0001), ganglion cell layer (P<0.0001), inner plexiform layer (P<0.0001), inner nuclear layer (P<0.0001), and outer nuclear layer (P<0.0001) were significantly higher in the XLAS group. The central RT of the XLAS group was significantly thinner than that of the control group (P<0.0001).

CONCLUSION

Temporal retinal thinning appears early in XLAS patients, especially in male patients. The thinning is mainly caused by structural abnormalities of the inner retina. This suggests that temporal retinal thinning could be helpful for the early diagnosis and follow-up of XLAS with noninvasive SD-OCT examination.

Outer retinal features in OCT predict visual recovery after primary macula-involving retinal detachment repair

Purpose

To find predictive markers for the visual potential in optical coherence tomography (OCT) one month after surgical repair of macula-involving rhegmatogenous retinal detachment (miRD) with and without internal limiting membrane (ILM) peeling.

Methods

This retrospective single-center, single-surgeon cohort study included 74 patients who underwent pars plana vitrectomy (PPV) for primary miRD between January 2013 and August 2020 with follow-up examinations for at least 6 months. Patients developing recurrent detachments, media opacities, or with an axial length over 27 mm were excluded from the analysis. LogMAR visual (VA) and LogRAD reading acuity (RA) ± standard deviation (SD), and OCT measurements 6 months after surgery were compared to OCT and VA measurements one month after surgery using multiple linear regression analysis for predictions.

Results

VA increased from 0.34 ± 0.25 at one month to 0.22 ± 0.21 after 6 months [p < 0.001; effect size = -0.662, 95% confidence interval (CI): -(0.99–0.33)]. The continuity of the external limiting membrane (ELM) and ellipsoid zone (EZ) increased between 1 and 6 months. Subfoveal ELM integrity after one month predicted VA [adjusted R² of 8.0%, F(2, 71) = 4.17, p = 0.018] and RA [adjusted R² of 29%, F(2, 27) = 6.81, p = 0.002] after 6 months. EZ integrity had a less pronounced predictive effect on VA and RA. ELM integrity after 1 month correlated with better reading acuity after 6 months (p = 0.016).

Conclusion

VA and morphological OCT parameters improve between 1 and 6 months after surgery for miRD. The grade of ELM is a better predictor for RA than for VA, explaining more variance.

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.

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.

Effect of silicone oil on peripapillary capillary density in patients with rhegmatogenous retinal detachment

Purpose

To evaluate the effect of silicone oil (SO) on peripapillary blood flow using OCT angiography.

Methods

This prospective case series recruited patients with unilateral rhegmatogenous retinal detachment (RRD) who underwent vitrectomy and SO tamponade. Patients were examined before SO removal and at 10 days, 1 month, and 3 months after SO removal on a spectral domain OCT angiography device (RTVue XR Avanti, Optovue Inc., CA, USA) for the measurement of radial peripapillary capillaries (RPC) vessel density (VD) in global field, superior hemifield, and inferior hemifield. Changes in RPC VD following SO removal were compared between affected eyes and contralateral eyes.

Results

Twenty-two patients were analyzed. The average duration of SO tamponade was 101.3 days (range, 90 to 119 days). After SO removal, global RPC VD increased by 1.3% (95%CI, 0.3 to 2.3%), compared with a − 0.4% (95%CI, − 1.4 to 0.7%) change in contralateral eyes (P = 0.007). The increase in RPC VD after SO removal mainly occurred in the superior hemifield, which was 1.6% (95%CI, 0.6 to 2.7%). The increase in RPC VD in the inferior hemifield was 1.0% (95%CI, − 0.2 to 2.1%) after SO removal.

Conclusions

We detected a mild increase in peripapillary capillary density after SO removal, mainly in the superior hemifield. Our results suggested that SO tamponade could have negative effect on peripapillary blood flow, possibly by capillary compression.

Evaluation of primary internal limiting membrane peeling in cases with rhegmatogenous retinal detachment

Background

Epiretinal membranes (ERMs) have been reported after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). Peeling of the internal limiting membrane (ILM) can prevent post-PPV ERM formation but has a potential negative impact on macular structure and function.

Purpose

To investigate the anatomical and functional outcomes of ILM peeling during PPV for primary RRD.

Methods

This was a prospective nonrandomized study that included 60 eyes of 60 patients with a primary macula-off RRD and less than grade C proliferative vitreoretinopathy (PVR). Eyes were allocated into 2 groups; Group A underwent PPV without ILM peeling and Group B had ILM peeling. At postoperative month 6, all patients underwent retinal imaging using spectral domain optical coherence tomography (OCT) and OCT angiography and macular function was assessed using multifocal electroretinogram (mfERG). Baseline characteristics and postoperative anatomical and visual outcomes were recorded and statistically analyzed.

Results

We enrolled 30 eyes of 30 patients in each group. In Group A, mean age was 44.6 years, while the mean age of Group B patients was 49.9 years. Postoperative LogMAR visual acuity was significantly better in Group A than in Group B (p < 0.001). ERMs were demonstrated on OCT in 13.3% of Group A and none of Group B patients (p = 0.04). Retinal dimples were found in 53.3% of Group B and none of Group A eyes (p < 0.001). OCTA showed a greater vessel density of the superficial capillary plexus (SCP) in Group A compared to Group B eyes (p = 0.046), while no difference was found regarding deep capillary vessel density (p = 0.7). Mean amplitude of mfERG P1 wave was significantly higher in Group A eyes than in Group B (p = 0.002). Both the SCP vessel density and P1 amplitude were positively correlated with visual acuity (p < 0.001).

Conclusion

This study suggests that ILM peeling prevents ERM development in eyes undergoing PPV for uncomplicated macula-off RRD, but potential damage to macular structure and function were found.

Trial registration Retrospectively registered on 09/24/2019 on ClinicalTrials.gov with an ID of NCT04139811.

Internal limiting membrane peeling versus no peeling during primary vitrectomy for rhegmatogenous retinal detachment: A systematic review and meta-analysis

BACKGROUND

Internal limiting membrane (ILM) peeling during primary vitrectomy for rhegmatogenous retinal detachment (RRD) prevents the formation of postoperative macular epiretinal membrane (ERM). However, studies that compared vitrectomy with and without ILM peeling for RRD, have reported controversial outcomes.

OBJECTIVE

To assess the efficacy of ILM peeling versus non-ILM peeling during vitrectomy for RRD by a systematic review and meta-analysis of published studies.

METHODS

PubMed, Medline, Web of Science, Embase databases, and the Cochrane Library were searched up to April 2018 to identify studies that compared primary vitrectomy with and without ILM peeling for RRD with at least six months follow-up. Primary outcomes were the rate of postoperative ERM formation and mean best corrected visual acuity (BCVA) change after vitrectomy. Rate of recurrence of retinal detachment (RD) was assessed as secondary outcome. Risk ratios (RRs) with 95% confidence intervals (CIs) expressed pooled results for rate of ERM formation and rate of RD recurrence in ILM peeling and non-ILM peeling groups. Pooled results for BCVA change in the two groups were expressed as Weighted Mean Difference (WMD) with 95% CIs.

RESULTS

Nine studies, one of which was a randomized controlled trial (RCT), with a total number of 404 eyes in the ILM peeling group and 365 eyes in the non-ILM peeling group, were included. The analysis from pooled data indicated a significant lower rate of postoperative ERM formation in the ILM peeling group compared to the non-ILM peeling group (9 studies, 769 eyes, RR = 0.14; CI: 0.07 to 0.28; P < 0.001). There was no statistical difference in mean BCVA change (9 studies, 769 eyes, WMD = 0.02; CI: -0.11 to 0.16; P = 0.75). Rate of recurrence of RD was lower in the ILM peeling group (6 studies, 603 eyes, RR = 0.32; CI = 0.17 to 0.61; P< 0.001).

CONCLUSION

ILM peeling during vitrectomy for RRD prevents the formation of macular epiretinal membrane postoperatively and reduces the incidence of RD recurrence, but better visual outcome was not found compared to non-ILM peeling vitrectomy.

Internal Limiting Membrane Peeling in Macula-off Retinal Detachment Complicated by Grade B Proliferative Vitreoretinopathy

PURPOSE

To investigate the clinical benefit of internal limiting membrane (ILM) peeling as a surgical adjunct in the repair of primary retinal detachment (RD) complicated by grade B proliferative vitreoretinopathy (PVR).

DESIGN

Retrospective, interventional, comparative case series.

METHODS

Setting, study population, observationalprocedures and Main outcome measures.

SETTING

Institutional.

STUDY POPULATION

Seventy-five consecutive patients who underwent vitrectomy for primary macula-off RD complicated by grade B PVR.

OBSERVATIONAL PROCEDURES

Patients were divided into an ILM peeling (Group P) and a no ILM peeling group (Group NP).

MAIN OUTCOME MEASURES

Anatomic success rate, best-corrected visual acuity, and spectral-domain optical coherence tomography (SD-OCT) characteristics were collected at 1 and 6 months.

RESULTS

In all, 37 eyes with ILM peeling were included in Group P and 38 eyes without ILM peeling were included in Group NP. The anatomic success rate after single surgery was higher in Group P (89%) than in Group NP (66%, P = .03). Mean final visual acuity was 0.41 ± 0.40 logMAR in Group P vs 0.43 ± 0.22 logMAR in Group NP (P = .82). We found no epiretinal membrane (ERM) formation in Group P, whereas 5 cases of ERM (20%) were detected in Group NP (P = .012). The 2 groups did not differ in terms of cystoid macular edema occurrence, macular thickness, or photoreceptor damage.

CONCLUSIONS

ILM peeling during vitrectomy in macula-off RD complicated by grade B PVR reduces the need for a second surgery for redetachment or macular pucker.

Functional and structural outcomes of ILM peeling in uncomplicated macula-off RRD using microperimetry & en-face OCT

PURPOSE

To investigate functional and structural outcomes of internal limiting membrane (ILM) peeling during primary vitrectomy for uncomplicated macula-off rhegmatogenous retinal detachment (RRD).

METHODS

In this prospective interventional randomized comparative study, 43 eyes (43 patients) were randomly divided into group A (20), and group B (23), with and without ILM peeling respectively. Patients were evaluated clinically, and by spectral-domain optical coherence tomography (SD-OCT) and microperimetry (MP) following silicone oil removal. Main outcome measures were functional-MP (mean and foveal retinal sensitivity; MRS, FRS) and best-corrected visual acuity (BCVA)-and anatomical-en-face image analysis (retinal dimples), and SD-OCT changes [epiretinal membrane (ERM), subretinal fluid (SRF), ellipsoid zone disruption, central subfoveal thickness (CSFT), and foveal contour].

RESULTS

All eyes achieved complete postoperative attachment with mean BCVA 1.0 ± 0.4 logMAR (6/60) in group A, and 0.4 ± 0.4 logMAR (6/15) in group B (p < 0.001). MRS and FRS were significantly higher in group B (p = 0.037 and 0.036 respectively). En-face OCT showed retinal dimples in all patients in group A (29.17 ± 7.67 dimples), compared to none in group B (p = 0.007). ERM did not develop in any eye in group A, while it developed in 17.4% of eyes in group B (p = 0.05).

CONCLUSION

Although ILM peeling prevented ERM, it resulted in poorer visual outcome in these uncomplicated RRD cases, and might be better reserved only for complicated cases.