Internal limiting membrane insertion technique combined with nerve growth factor injection for large macular hole

Effect of internal limiting membrane surgical techniques on the idiopathic and refractory management of macular holes: a systematic review and meta-analysis

Macular holes (MHs), including atraumatic idiopathic and refractory MHs, affect central vision acuity due to full-thickness defects in the retinal tissue. The existing controversy regarding the pathophysiology and management of MHs has significantly improved with the implementation of internal limiting membrane (ILM) surgical techniques and improved MH closure rates. Thus, to determine the effect of ILM techniques on large idiopathic and refractory MH management, the present study systematically reviewed 5910 original research articles extracted from online literature databases, including PubMed, Cochrane, Google Scholar, and Embase, following the PRISMA guidelines. The primary outcome measures were MH closure rate and postoperative visual acuity. A total of 23 randomized controlled trials (RCTs) with adequate patient information and information on the effect of ILM peeling, inverted ILM flaps, autologous retinal transplantation (ART), and ILM insertion techniques on large idiopathic and refractory MH patients were retrieved and analyzed using RevMan software (version 5.3) provided by the Cochrane Collaboration. Statistical risk of bias analysis was also conducted on the selected sources using RoB2, which showed a low risk of bias in the included studies. A meta-analysis indicated that the inverted ILM flap technique had a significantly greater MH closure rate for primary MH than the other treatment methods (OR = 3. 22, 95% CI 1.34-7.43; p = 0.01). Furthermore, the findings showed that the inverted ILM flap group had significantly better postoperative visual acuity than did the other treatment options for patients with idiopathic MH (WMD = - 0.13; 95% CI = 0.22-0.09; p = 0.0002). The ILM peeling technique had the second highest statistical significance for MH closure rates in patients with idiopathic MH (OR = 2. 72, 95% CI: 1.26-6.32; p = 0.016). In refractory MHs, autologous retinal transplant (ART) and multilayer ILM plug (MIP) techniques improve the closure rate and visual function; human amniotic membrane grafting (hAMG) provides a high degree of anatomical outcomes but disappointing visual results. This study demonstrated the reliability and effectiveness of ILM techniques in improving the functional and anatomical outcomes of large idiopathic and refractory MH surgery. These findings will help clinicians choose the appropriate treatment technique for patients with idiopathic and refractory MH.

Inverted Internal Limiting Membrane Flap versus Internal Limiting Membrane Insertion Technique for Large Macular Holes: A Meta-Analysis

PURPOSES

This meta-analysis aimed to compare and evaluate the morphological and functional outcomes between the inverted internal limiting membrane (ILM) flap and ILM insertion techniques in the treatment of large macular holes (MHs).

METHODS

The PubMed, Embase, and Cochrane Library databases were searched for relevant studies comparing the two techniques for the treatment of large MHs. The primary outcome measures included the MH closure rate, preoperative and postoperative best-corrected visual acuity (BCVA), MH closure patterns, and external limiting membrane (ELM) and ellipsoid zone (EZ) recovery. Statistical analyses were performed using RevMan 5.3 software.

RESULTS

Two randomized controlled trials and four retrospective studies were included in this meta-analysis. The MH closure rate did not significantly differ between the two groups (P = .93). Postoperative BCVA was not significantly different between the two groups at 3 months (P = .20) or 6 months (P = .51). ELM and EZ recovery were also similar between the two groups. However, the results for postoperative BCVA and outer retinal structure recovery tended to favor the ILM flap group based on the forest plot. There was no significant difference between the two groups for the U-shape (P = .26), V-shape (P = .65), and W-shape closure types (P = .38).

CONCLUSIONS

Our meta-analysis provides evidence that the MH closure rate and visual function outcomes are similar between the ILM flap and ILM insertion techniques in large MHs. However, based on the forest plot, postoperative BCVA and outer retinal layer reconstruction tended to favor the ILM flap technique. Further studies with larger sample sizes are required to confirm the superiority of the ILM flap to the ILM insertion technique.

Internal limiting membrane peeling combined with mouse nerve growth factor injection for idiopathic macular hole

BACKGROUND

The study was intended to confirm whether Pars Plana Vitrectomy (PPV) with Internal Limiting Membrane (ILM) peeling and intravitreal injection mouse Nerve Growth Factor(mNGF) was effective for the treatment of Idiopathic Macular Hole(IMH) by Optical Coherence Tomography Angiography(OCTA) and microperimetry.

METHODS

A retrospective study was performed in adults' patients. A total of 44 eyes (March 2021-October 2021) with IMH who received surgical treatment in the Affiliated Eye Hospital of Nanchang University in Nanchang City, Jiangxi Province were selected. The subjects were treated using PPV combined with ILM peeling and intravitreal mNGF (combined group) or PPV combined with ILM peeling (placebo group). The Best Corrected Visual Acuity (BCVA), Optical Coherence Tomography Angiography (OCTA) and MP-3 microperimetry were carried out and observed at baseline, 1 week(1W), 1,3 and 6 months (1 M,3 M,6 M) postoperatively.

RESULTS

The minimum diameter of MH were (568.650 ± 215.862)μm and (533.348 ± 228.836)μm in the Placebo and Combine group pre-operative. During the observation, the macular hole closure rate in the placebo group and combined group were 90% and 95.8% respectively and the difference was not statistically significant(p = 0.583). Compared to pre-surgery, the perimeter and circularity of Foveal Avascular Zone (FAZ) in the placebo group decreased at 1,3,6 M (p = 0.001, < 0.001, < 0.001) and 1W,1,6 M (p = 0.045,0.010, < 0.001) post-surgery respectively. And the perimeter and circularity of FAZ showed significant reduction in the combined group at 1,3,6 M (p = 0.005,0.004, < 0.001) and at each follow-up time point (all values of p < 0.001). The vascular density of SCP increased at 1W(p = 0.031) and 6 M(p = 0.007), the perfusion density of SCP was significantly improved at each follow-up time point (p = 0.028, 0.011, 0.046, 0.004) in the combined group. The BCVA in the combined group was more obvious than that in the placebo group at 1 M, 3 M and 6 M after operation (t₁ = 2.248, p₁ = 0.030; t₃ = 3.546, p₃ = 0.001; t₆ = 3.054, p₆ = 0.004). The changes of BCVA in the combined group was more conspicuous than that in the placebo group at each follow-up time point, and the difference was statistically significant (t₁ = 2.206,p₁ = 0.033;t₂ = 2.54,p₂ = 0.015;t₃ = 3.546,p₃ = 0.001;t₆ = 3.124,p₆ = 0.003).At 1 M, 3 M and 6 M, the MRS of 2° and 4° in the combined group was better than that in the placebo group(t = -2.429,-2.650,-3.510,-2.134,-2.820,-3.099 p = 0.020,0.011,0.001,0.039,0.007,0.004). During various time points, the MRS of 12°in the combined group was better than that in the placebo group, the difference was statistically significant (t = -3.151, -3.912, -4.521, -4.948, p₁ = 0.003, < 0.001, < 0.001 < 0.001). The integrity of External Limiting Membrane (ELM) in combination group was better than that in placebo group at 6 M postoperative(p = 0.022) and that of Ellipsoid Zone(EZ) was preferable in the combined group at 3 M and 6 M after surgery(p = 0.012,0.004). Correlation analysis showed that the integrity of EZ was correlated with 12°MRS at 1 M, 3 M and 6 M after surgery(r = -0.318, -0.343,-0.322;p = 0.023,0.033, < 0.001). There was no correlation between postoperative ELM integrity and postoperative BCVA and 12°MRS(p > 0.05).

CONCLUSIONS

Our results manifested that PPV combined with ILM peeling and intravitreal injection mNGF might be more effective for initial IMH. This method increased the blood flow, MRS and promoted the recovery of ELM and EZ in the macular and might improve the visual function of patients postoperatively.

Comparative Study of Conventional Inverted ILM Flap Covering and ILM Flap Filling Technique in Idiopathic Macular Hole Treatment: A Meta-Analysis and Systematic Review

Objective

This meta-analysis was performed to evaluate the anatomical efficacy and functional improvement of the conventional inverted internal limiting membrane (ILM), flap covering technique, and ILM flap filling technique for patients with idiopathic macular hole (MH).

Methods

Literature from Pubmed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science were comprehensively retrieved. The primary outcomes included the MH closure rate and postoperative best-corrected visual acuity (BCVA). The secondary outcomes were the proportion of external limiting membrane (ELM) and ellipsoid zone (EZ) defect recovery. Pooled odds ratios (ORs), weighted mean differences (WMDs), and 95% confidence intervals (CIs) were calculated using STATA 17.0 software.

Results

7 studies that contained 139 eyes in the inverted ILM flap covering group and 121 eyes in the ILM flap filling group were selected. Pooled data suggested that the surgical treatment resulted in an overall MH closure rate of up to 97.12% (135/139 eyes) in the inverted ILM flap covering group and 99.17% (120/121 eyes) in the filling group, with no significant difference between the 2 groups (OR = 1.98, 95% CI: 0.55 to 7.09, and P=0.29). Similarly, the 2 techniques demonstrated equal effectiveness on the anatomical closure in MH with the average diameter smaller than 650 μm (OR = 2.17, 95% CI: 0.48 to 9.77, and P=0.31) and larger than 650 μm (OR = 1.58, 95% CI: 0.14 to 17.37, and P=0.71). However, compared with the filling technique, the inverted ILM flap covering technique was superior in postoperative BCVA (WMD = 0.11, 95% CI: 0.04 to 0.18, and P=0.0017) and presented a significantly higher proportion of reconstitution of ELM (OR = 0.02, 95% CI: 0.00 to 0.08, and P < 0.0001) and EZ (OR = 0.11, 95% CI: 0.04 to 0.32, and P=0.0001).

Conclusion

The inverted ILM flap covering technique was associated with the superior reconstitution of outer layers of the retina, including ELM and EZ, and more improvement in postoperative BCVA than the ILM flap filling technique.

Update on surgical management of complex macular holes: a review

Modern surgical interventions effectively treat macular holes (MHs) more than 90%. Current surgical treatment for MHs is pars plana vitrectomy with epiretinal membrane, internal limiting membrane (ILM) peeling, gas endotamponade, and prone posturing postoperatively. However, a small subset of MHs imposes challenges to surgeons and frustrations on patients. A narrative review was performed on the surgical treatment of challenging MHs including large and extra-large MHs, myopic MHs with or without retinal detachment, and chronic and refractory MHs. There are robust data supporting inverted ILM flap as the first-line treatment for large idiopathic MHs and certain secondary MHs including myopic MHs. In addition, several studies had shown that ILM flap manipulations in combination with surgical adjuncts increase surgical success, especially in difficult MHs. Even in eyes with limited ILM, surgical options included autologous retinal graft, human amniotic membrane, and creation of a distal ILM flap that can assist in MH closure even though the functional outcome may be affected by the MH chronicity. Despite relative success anatomically and visually after each technique, most techniques require a long-term study to analyze their safety profile and to establish any morphological changes of the MH plug in the closed MHs.

MANAGEMENT OF LARGE OR RECURRENT MACULAR HOLES

Purpose of Review

To review and critically appraise the recent literature about new surgical techniques for the management of large or recurrent macular holes.

Recent Findings

A variety of surgical approaches have recently been developed ranging from autologous retinal grafts to amniotic membrane transplant with varying levels of anatomical and visual success.

Summary

More data is needed to determine if one technique is superior to others. However, with a variety of grafts, adhesives, and tamponades at their disposal, vitreoretinal surgeons have an extensive array of options to approach complex macular holes.

Premacular Cells as Source of Neurotrophic Factors in Idiopathic Macular Holes

Purpose: To describe the presence of neurotrophic growth factors and histopathologic characteristics of internal limiting membrane (ILM) specimens obtained from large idiopathic full-thickness macular holes (FTMH). Methods: In 24 eyes of 24 patients with FTMH of diameter >400 µm, ILM specimens were harvested directly at the edge surrounding the macular hole during vitrectomy with peeling. We performed interference and phase contrast microscopy of flat mounts followed by immunostaining and transmission electron microscopy. Primary antigens directed against neurotrophic growth factors as well as antigens to glial and ganglion cells were used. Topographic relationship of cells and collagen was demonstrated by serial ultrathin sectioning. Results: Immunofluorescence microscopy demonstrated the presence of glial-derived neurotrophic factor and ciliary neurotrophic factor. Expression of vimentin, glial fibrillary acidic protein (GFAP), neurofilament, calretinin, and melanopsin was seen positive too. Cellular retinaldehyde-binding protein was seen positive in half of the specimens. Co-localisation of anti-GFAP as well as anti-vimentin with neurotrophic factors was found. Electron microscopy revealed cells exclusively on the vitreal side of the ILM. Cell fragments on the retinal side were rarely seen. Conclusion: In large FTMH, ILM specimens present positive immunolabelling of neurotrophic factors. The co-localization with macroglial cell markers suggests a premacular cell composition as a source of the neurotrophic factors. Ultrastructurally, premacular cells were found on the vitreal side of the ILM and not within the collagen network of the ILM itself.