The relationship between a dissociated optic nerve fibre layer appearance after macular hole surgery and Muller cell debris on peeled internal limiting membrane

Internal Limiting Membrane Peeling for Large Macular Holes Induces Only Structural Remodeling without Functional Impairment Over 12 Years

PURPOSE

To evaluate the very long-term functional and structural outcomes of internal limiting membrane (ILM) peeling for full-thickness macular holes (FTMH).

DESIGN

Observational case series nested within a multicenter, randomized, controlled clinical trial (RCT) (ClinicalTrials.gov: NCT00190190).

SUBJECTS

Patients who underwent vitrectomy with or without ILM peeling for an idiopathic large FTMH in a tertiary ophthalmology center, with a minimum follow-up of 10 years after surgery.

METHODS

Review of charts, spectral-domain OCT (SD-OCT) scans, OCT angiography (OCTA) scans, and microperimetry of patients originally enrolled in the RCT.

MAIN OUTCOME MEASURES

Primary outcome was functional assessment in both groups (ILM peeling or not) including the retinal sensitivity (RS), distance and near best-corrected visual acuity (BCVA), and number of eyes achieving ≥0.3 logarithm of the minimum angle of resolution >10 years after surgery. Secondary outcomes were structural assessment in the entire 3 × 3-mm and 6 × 6-mm areas, and regionally in the different areas of the ETDRS grid: OCT and OCTA biomarkers in both groups and fellow eyes.

RESULTS

Thirteen eyes of 13 patients with a mean follow-up of 12 ± 0.73 years were included. The mean RS and BCVA, or visual improvement did not differ between ILM peeling (n = 8) and no peeling (n = 5) (all P > 0.05). The dissociated optic nerve fiber layers on en face OCT were only observed in eyes with ILM peeling, predominantly in temporal parafoveal (20%) and perifoveal (19%) rings. The mean total retinal thickness and inner retinal thickness in the parafoveal ring were significantly lower in peeled eyes (309 ± 11 μm and 94 ± 9 μm respectively) versus nonpeeled eyes (330 ± 21 μm and 108 ± 11 μm respectively; P = 0.037 and P = 0.040), without significant difference in ganglion cell or retinal nerve fiber layers. Accordingly, the mean superficial capillary plexus density in the parafoveal ring was significantly lower in eyes with peeling versus without (39.65 ± 3.76 % versus 47.22 ± 4.00; P = 0.005). The mean foveal avascular zone area was smaller in eyes with peeling versus without (0.24 ± 0.05 mm2 vs. 0.42 ± 0.13 mm2, respectively, P = 0.005).

CONCLUSIONS

Despite persistent structural changes especially in the parafoveal ring, ILM peeling for idiopathic large FTMH did not seem to impact long-term RS or BCVA over 12 years.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Long-Term Quantitative Analysis of Inner Retinal Dimples and Visual Function Post Internal Limiting Membrane Peeling in Macular Diseases

INTRODUCTION

Inner retinal dimples (IRDs) are frequently detected after internal limiting membrane (ILM) peeling. However, the distribution of IRDs and its effect on postoperative visual function remain unclear. We aim to quantify the distribution of IRDs after ILM peeling in different macular diseases and analyze its influence on postoperative visual function.

METHODS

We retrospectively reviewed patients undergoing vitrectomy with ILM peeling and followed up until 12 months in our center. The distribution of IRDs were quantitatively determined using optical coherence tomography (OCT) and OCT angiography in a different sector of Early Treatment Diabetic Retinopathy Study grid. Visual function was evaluated by retinal sensitivity (RS) using microperimetry. Spearman correlation was performed between RS and IRDs within the same sectors. Multivariate linear regression analysis was performed to analyze the association between baseline characteristics and IRDs.

RESULTS

A total of 43 idiopathic macular hole (iMH) cases, 56 idiopathic epiretinal membrane (iERM) cases and 42 myopic foveoschisis (mFS) cases were included. IRDs increased gradually at ILM-peeled area, interrupting ganglion cell layer. Most IRDs were observed in temporal sector. A negative correlation was depicted between the increase of IRDs and the progress of RS at both perifovea and parafovea in iERM, but only at perifovea in iMH. No significant correlation between the change of IRDs and RS was found in mFS. Multivariable linear regression model showed that preoperative axial length was significantly associated with postoperative IRDs in all patients.

CONCLUSIONS

IRDs distributed mostly at temporal sector after ILM peeling, interrupting ganglion cell layer. IRD progression may influence postoperative RS only in iMH and iERM. Ophthalmologists may avoid temporal sector especially in eyes with normal axial length or strong ILM-ERM adherence.

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.

A randomised controlled trial evaluating internal limiting membrane peeling forceps in macular hole surgery

Purpose

To assess study design and a range of anatomical and functional changes after internal limiting membrane (ILM) peeling using forceps developed for atraumatic ILM pick-up compared to standard forceps.

Methods

We conducted a masked proof-of concept randomised controlled trial (RCT) on 65 patients who underwent ILM peeling for idiopathic full-thickness macular hole (FTMH) using etched-tip forceps (etched-tip group, 33 eyes) compared to standard ILM forceps (smooth-tip group, 32 eyes). Patients were assessed preoperatively, 3 weeks, 3 and 6 months postoperatively.

Results

The primary closure rate was 95.4%. There was no statistically significant difference between the groups in terms of final visual acuity (66.9 vs 70.9 ETDRS letters, p = 0.13), difference of visual field mean deviation (1.32 vs 1.14 decibels), and number of eyes with pick-up-related retinal haemorrhages (16% vs 16%, p = 0.96), swelling of arcuate nerve fibre layer lesions (63% vs 55%, p = 0.54), number of dissociated optic nerve fibre layer lesions (31.4 vs 41.0, p = 0.16), nor inner retina defects (37% vs 22%, p = 0.17). Similar changes in inner retinal volumes were detected in all 9 sectors of an ETDRS grid except for a trend (p = 0.06) towards a lower reduction in the inferior inner sector in the etched-tip group.

Conclusions

The study was successfully completed with masking maintained and a low risk of bias. Multiple endpoints relating to ILM peeling were assessed, and estimates were provided that can be used for future studies. Although the study was not powered to assess any specific endpoint, the anatomical and functional outcomes assessed did not significantly differ.

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.

Quantifying surgical skill in macular surgery

PURPOSE

To evaluate the relationship between patient outcome and surgical experience by developing an objective quality measure of macular hole surgery based on forceps damage to the inner retina.

METHODS

We retrospectively examined 3 macular hole case series >1 year after pars plana vitrectomy, internal limiting membrane peeling and gas tamponade. The patients were operated by (1) a novice surgeon (<20 cases), (2) an intermediate (150+ cases) and (3) an experienced surgeon (2000+ cases). Primary outcome was inner retinal volume defect as segmented from optical coherence tomography (GCL++: thickness from internal limiting membrane to inner plexiform layer). Secondary outcome was retinal function measured by confocal microperimetry using a custom scanning protocol.

RESULTS

Thirty-two patients were examined: 11, 10 and 11 patients in the novice, intermediate and experienced surgeon group, respectively. Median GCL++ volume defect was 23.68 × 10⁶  μm³ (IQR: 22.77 × 10⁶ -44.81 × 10⁶ μm³ ), 8.42 × 10⁶ μm³ (IQR: 4.86 × 10⁶ -10.03 × 10⁶ μm³ ) and 3.55 × 10⁶ μm³ (IQR: 1.44 × 10³ -7.94 × 10⁶ μm³ ) in the novice, intermediate and experienced surgeon group, respectively (p = 0.0004). The novice surgeon volume defect differed significantly from the intermediate and experienced surgeon (p = 0.016 and p = 0.0002, respectively). A subset of 12 patients underwent microperimetry measurements demonstrating correlation between inner retinal volume defect and reduced retinal sensitivity (p = 0.02).

CONCLUSIONS

Forceps induced inner retinal damage commonly occurs during initiation of internal limiting membrane peeling in macular hole surgery. Damage to the structure and function of the inner retina seems to correlate to surgical experience.

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 IN PATIENTS WITH MULTIFOCAL VERSUS MONOFOCAL INTRAOCULAR LENSES

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Efficacy of Pars Plana Vitrectomy with Internal Limiting Membrane Peeling for Treatment of Large Idiopathic Full-Thickness Macular Holes

Purpose

To evaluate anatomical and visual outcomes of pars plana vitrectomy (PPV) with internal limiting membrane peeling (ILMP) in large idiopathic full-thickness macular holes (FTMH). Predictive factors also formed part of the study.

Patients and Methods

A retrospective review of medical charts and optical coherence tomography images of patients with large idiopathic FTMH (≥400 µm) was conducted.

Results

One hundred and fifty-eight eyes of 155 patients with a mean age of 62.94±7.50 years were included in the study. Mean preoperative visual acuity (VA) was 1.26±0.36 logMAR. Mean preoperative minimum linear diameter (MLD) and basal linear diameter (BLD) were 644.89±136.85 µm and 1208.11±307.14 µm, respectively. At 12 weeks postoperative follow-up, FTMH closure rate was 61.39% and mean postoperative BCVA was 0.92±0.36 logMAR. Multivariate logistic regression analyses showed the anatomical outcome was significantly associated with BLD ≤1200 µm, preoperative vitreomacular interface (VMI) disorder and extended ILMP (a radius of 2 disc diameters), whereas only postoperative ellipsoid loss ≤500 µm was significantly associated with visual outcome. In subgroup analyses, the large FTMH group (400–600 µm) had significantly better results in closure rate (70.97% vs 55.21%, P = 0.047) and visual results (P = 0.031) than the extra-large FTMH group (>600 µm).

Conclusion

PPV with conventional ILMP provided relatively low closure rate in large FTMH. Surgical success was significantly associated with BLD ≤1200 µm, no preoperative VMI abnormality, extended ILMP and postoperative ellipsoid defect ≤500 µm. Therefore, we suggest the extended ILMP if conventional ILMP technique is used. The large FTMH group had significantly better surgical outcomes than the extra-large group, so there is a need for reclassification of large FTMH.

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.

Evaluation of Vision-Related Quality of Life after Autologous Internal Limiting-Membrane Transplantation for Refractory Macular Holes

Purpose

To evaluate the vision-related quality of life of vitrectomy combined with autologous internal limiting membrane (ILM) transplantation for refractory macular holes (MHs).

Methods

There were 40 eyes with refractory MHs included, and all eyes received 23 G vitrectomy and ILM peeling with autologous ILM transplantation. Preoperative and postoperative basic conditions were recorded. The Chinese version of the vision-related quality-of-life scale was used to evaluate patients after operation. Quality of life, postoperative visual acuity, and size of MHs before operation were assessed with Spearman rank correlations.

Results

All patients were followed up for 3 months after surgery. Mean postoperative best-corrected visual acuity had significantly improved after surgery. Vision-related quality of life of patients after surgery was closely related to the MH index, but negatively correlated with best-corrected visual acuity before and after surgery.

Conclusion

The anatomical structure of refractory MHs with ILM peeling combined with autologous ILM transplantation was largely reduced, and the visual acuity of patients improved significantly.

FACTORS ASSOCIATED WITH DEVELOPMENT OF DISSOCIATED OPTIC NERVE FIBER LAYER APPEARANCE IN THE PIONEER INTRAOPERATIVE OPTICAL COHERENCE TOMOGRAPHY STUDY

PURPOSE

To assess the relationship of dissociated optic nerve fiber layer (DONFL) and intraoperative membrane-peeling dynamics as visualized using intraoperative optical coherence tomography (OCT), and to evaluate the functional implications of DONFL.

METHODS

This was a post hoc analysis of eyes undergoing membrane peeling for vitreomacular interface disorders in the prospective PIONEER intraoperative OCT study. Retinal layer measurements in preincision and postpeel intraoperative OCT images were obtained. The primary outcome was development of DONFL appearance on spectral domain OCT at 6-month follow-up. Secondary outcomes included correlation of DONFL with surgical technique, surgical indication, intraoperative OCT findings, and retinal sensitivity.

RESULTS

Ninety-five eyes were included. The prevalence of DONFL at 6 months was 36%. Increased inner retinal layer thickness on intraoperative OCT immediately after membrane peeling was associated with development of DONFL (P < 0.01). Macular hole repair was significantly associated with DONFL appearance. Peel technique (forceps vs. diamond-dusted membrane scraper) was not associated with DONFL. There was no difference in retinal sensitivity or visual acuity between eyes with or without DONFL.

CONCLUSION

Acute postpeel increase in inner retinal thickness and macular hole repair were associated with development of DONFL appearance. However, it is unclear whether the surgical indication (e.g., macular hole) or the surgical manipulations performed (e.g., internal limiting membrane peeling) is the major factor that has an impact on DONFL appearance. Overall, these findings suggest that one mechanism in the development of DONFL appearance may be intraoperative trauma to the inner retina, potentially during internal limiting membrane peeling (e.g., macular hole repair).

Non-inverted pedicle internal limiting membrane transposition for large macular holes

PURPOSE

The purpose of this study is to investigate the effectiveness of a new surgical technique of non-inverted pedicle internal limiting membrane (ILM) transposition for the treatment of eyes with large macular hole.

METHODS

This is a retrospective, consecutive, interventional case series. Twelve eyes of 12 consecutive patients who underwent vitrectomy for the treatment of a large macular hole (MH size > 400 µm) were treated. ILM was peeled and left with a pedicle attached to the superior temporal retina. The macular hole was covered by transposition of the pedicle ILM in a non-inverted way. Preoperative and postoperative best-corrected visual acuity (BCVA), SD-OCT image, macular sensitivity by microperimetry, and multifocal electroretinogram (mERG) response were evaluated. All of the patients were followed for more than 3 months.

RESULTS

Postoperative OCT examination confirmed 11 of 12 macular hole closed (91.7%). Six macular hole filled with silicone oil closed as early as the next day. The postoperative BCVA significantly increased compared with preoperative BCVA (P = 0.002). The improvement of macular sensitivity within 2° and 8° circle was also statistical significant (P = 0.018 and P = 0.017, respectively). Fixation stability, shown as the percentage of fixation point within the 2° circle and 4° circle, was remarkably improved (P = 0.017 and P = 0.018, respectively). The R1/R2 and R1/R4 ring ratios also increased significantly as compared with that of baseline.

CONCLUSION

These findings indicate that the non-inverted pedicle ILM transposition results in a high incidence of anatomic closure with good visual outcome for the treatment of large macular hole.

Vitrectomy with a modified temporal inverted limiting membrane flap to reconstruct the foveolar architecture for macular hole retinal detachment in highly myopic eyes

PURPOSE

We investigated the surgical results of macular hole retinal detachment (MHRD) with a modified C-shaped temporal inverted internal limiting membrane (ILM) flap to reconstruct the foveolar architecture in highly myopic eyes.

METHODS

Eighteen highly myopic eyes with MHRD in 17 patients who underwent a vitrectomy with a modified C-shaped temporal inverted ILM flap were followed for 12 months. Anatomic outcomes were evaluated by fundus examinations and optical coherence tomography. The preoperative and postoperative best-corrected visual acuities (BCVAs) were compared as functional outcomes.

RESULTS

Women accounted for 88% of the MHRD patients. The mean age was 60.2 ± 8.2 years. The mean axial length was 29.25 ± 2.10 mm. Type 1 and type 2 MHRD was present in four eyes and 14 eyes, respectively. After a single surgery, the hole was closed in 18 eyes (100%). Retinal attachment was achieved in 95%. Persistent shallow subretinal fluid (SRF) was noted in one case, which was resolved at follow-up. The surgery significantly improved BCVAs (from 1.7 ± 0.6 to 0.72 ± 0.4 logarithm of the minimum angle of resolution units [p < 0.001]) at the last visit. In total, 94.4% of the eyes had restored foveolar architecture. Ellipsoid zone recovery within the foveola was found in 77.8% of the eyes.

CONCLUSION

A vitrectomy and modified C-shaped inverted temporal ILM flap is effective for closing MHs, reattaching the retina, restoring the foveolar architecture and significantly improving the postoperative BCVA in MHRD patients. This technique is feasible, and we propose 'presumed' Müller cell cone repair in MHRD surgery.