Contractility of inverted internal limiting membrane flap after vitrectomy for macular hole

doi:10.21203/rs.3.rs-618406/v1

Download PDF

Research Article

Contractility of inverted internal limiting membrane flap after vitrectomy for macular hole

https://doi.org/10.21203/rs.3.rs-618406/v1

This work is licensed under a CC BY 4.0 License

You are reading this latest preprint version

We investigated the postoperative visual outcomes and morphological changes of the internal limiting membrane (ILM) flap, in patients who underwent the inverted ILM flap technique for macular hole (MH). Between August 2018 and February 2020, 22 eyes of 22 patients with idiopathic or myopic MH who underwent vitrectomy with ILM flap were included in this study and followed-up for more than six months. Postoperative MH status, comparison of best-corrected visual acuity (BCVA) before and six months after surgery, changes in the ILM flap area at one and six months postoperatively, and the factors related to changes in ILM flap size, were analyzed. MH closure was achieved in all of the patients. The BCVA at six months postoperatively (0.18 ± 0.15) was significantly better than the preoperative BCVA of 0.63 ± 0.37 (P = 0.000005, paired t-test). The area of the ILM flap decreased significantly from 3.25 ± 1.27 mm² at one month to 3.13 ± 1.23 mm² at six months (P = 0.024, Wilcoxon signed-rank test). Two eyes showed an ILM flap contraction of more than 20%, and one eye required re-operation due to an increase in metamorphopsia and decreased visual acuity. Among age, sex, ILM flap area at one month, preoperative BCVA, and axial length, ILM flap contraction was correlated with patient age and ILM flap area. Although vitrectomy with the inverted ILM flap technique confers a good visual outcome, the ILM flap may contract in younger patients.

Ophthalmology

Nuclear Medicine & Medical Imaging

macular hole

vitrectomy

internal limiting membrane

optical coherence tomography

FIB/SEM

Since the usefulness of vitrectomy for macular holes (MHs) was reported by Kelly and Wendel, surgical treatment for MH has become possible¹. Furthermore, with the introduction of internal limiting membrane (ILM) peeling, both postoperative anatomical MH closure and improvement of visual function have been achieved with good and stable results.² However, in some cases, such as large MH, long-term MH, and myopic MH, treatment was difficult.³ Michalewska et al. reported that the ILM flap technique can close refractory MH and continuously improve the foveal architecture.⁴ Subsequent papers also reported that the ILM flap technique is superior in closing refractory MH.^5–12

On the other hand, placing the ILM flap over the macula may create a scaffold for cell proliferation, which may lead not only to MH closure but also to epiretinal membrane-like proliferative tissue formation. In our previous report, we described a case of MH with macular pucker due to contraction of the ILM flap after vitrectomy with silicone oil injection.¹³ However, there are no other reports on the changes that occur in the ILM flap after vitrectomy with gas tamponade.

With the advancement of optical coherence tomography (OCT), it has become possible to capture changes in the fine structure of the retina, and to quantitatively observe changes in the vitreous-retinal interface, including the shape of the ILM flap. In this study, we investigated changes in postoperative MH status and visual acuity after vitrectomy for MH, using the inverted ILM flap technique. Furthermore, changes in the ILM flap were compared between one month and six months after vitrectomy, and the clinical factors affecting the changes in the ILM flap were examined.

This study included 22 eyes of 22 patients who underwent vitreous surgery for MH. The MHs were idiopathic in 13 eyes and myopic in nine eyes. The clinical characteristics of the patients are summarized in Table 1. Compared to the myopic MH group, the idiopathic MH group was significantly older, had a larger MH size, and had poor preoperative BCVA.

MH closure was observed in 73% of the eyes at one week after vitrectomy. In the remaining 27% of cases, although the MH was still open, the ILM flap covered the MH. Restoration of ELM continuity was seen in 18% of eyes at one week, 68% at one month, and 91% at six months. Recovery of ellipsoid zone continuity was seen in 0% of eyes at one week, 50% at one month and 73% at six months postoperatively (Fig. 1).

The mean BCVA (log MAR) at six months postoperatively was 0.18 ± 0.15, which was significantly better than the preoperative BCVA of 0.63 ± 0.37 (P = 0.000005, paired t-test; Fig. 2). Correlation analyses revealed that postoperative BCVA after six months was significantly correlated with MH size (r = 0.603, P = 0.003), preoperative BCVA (r = 0.727, P = 0.0001), and the size of the ILM flap at one month (r = 0.468, P = 0.028). Multivariate linear regression analyses with stepwise regression revealed that preoperative BCVA was a significant factor associated with postoperative BCVA (β = 0.727, P = 0.0001).

The ILM flap was clearly observed in the OCT en face image in the vitreoretinal interface region (Fig. 3). The area of the ILM flap decreased significantly from 3.25 ± 1.27 mm² at one month to 3.13 ± 1.23 mm² at six months (P = 0.024, Wilcoxon signed-rank test; Fig. 4). Two eyes with idiopathic MH and three eyes with myopic MH (a total of five eyes, 23%), showed ILM flap contraction of 5% or more. Two eyes out of the three eyes with myopic MH, had more than 20% contraction of the ILM flap. In one eye, BCVA decreased, and metamorphopsia was observed with the contraction of the ILM flap. As a result, ILM flap peeling was required (Fig. 5, supplemental video 1 and 2). Multiple regression analysis was performed using two factors related to ILM flap contraction: patient age and ILM flap area at one month postoperatively, which were selected by a stepwise method among the preoperative and early postoperative clinical findings including sex, patient age, MH size, preoperative BCVA, axial length, and ILM flap area at one month postoperatively. Patient age and the area of the ILM flap at one month postoperatively were found to be significant factors related to the contraction of the ILM flap (Table 2).

In this study, we examined the surgical outcomes and postoperative morphological changes of the ILM flap in patients who underwent MH coverage with a hinged ILM flap made on the temporal side after ILM peeling. In all cases, the MH was closed and postoperative BCVA significantly improved. However, in some cases, the ILM flap contracted after the surgery.

The mechanism of MH closure by the ILM flap technique is thought to be multifactorial. The ILM flap may serve as a scaffold for Müller cell proliferation and migration during the MH closure, and may promote Müller cell activation. Furthermore, neurotrophic factors and bFGF produced by activated Müller cells and present on the surface of the ILM, may contribute to MH closure.¹⁴ In this study, as in previous reports, flap closure was frequently seen in OCT images during the early postoperative period.⁵ Flap closure has been reported to allow closure of large MHs that would likely remain open without this technique, and to continuously improve the integrity of the foveal structure. In fact, in comparison with ILM peeling, the inverted ILM flap technique showed significantly higher closure rates than a conventional ILM peeling, in MHs greater than 400 µm,¹⁵; in patients with myopic MH, the inverted ILM flap technique has been shown to be more effective than ILM peeling in terms of closure rate, foveal structure, and postoperative BCVA.¹⁰ However, there have been reports of poor anatomical and visual results associated with inverted ILM flaps compared to ILM peeling, suggesting potential limitations of the ILM flap technique for repairing refractory MH.¹⁶ Between the method of covering the MH with ILM flap and the inverted ILM flap technique that plugs the MH, the cover group had better anatomical recovery and early postoperative visual acuity.¹⁷ In addition, the method of ILM insertion within the MH had inferior anatomical and visual results compared to the method of ILM flap covering over the MH. These findings suggest that insertion of the ILM into the MH during MH surgery may interfere with the reconstruction of the outer retinal layer and impede visual recovery.¹⁸

Michalewska et al. reported the original method of covering the MH with an internal limiting membrane around the MH, which was followed by the temporal ILM flap which covers the MH as a single sheet,¹⁹ the pedicle ILM transposition flap method,²⁰ a large semicircular inverted ILM flap,²¹ and multiple ILM flaps stacked on top of each other to resemble cabbage leaves.²² We have devised and used a method of ILM peeling and temporal side ILM flap over the MH. The advantages of this technique are that the ERM around the MH can be completely removed, the ILM flap is large enough to cover the MH, and it can be applied to cases in which ILM peeling was previously performed. As previously reported, it is also possible to create an ILM flap above the MH.²³

In contrast, the ILM flap may contract, as shown in this study and in previous reports.^13,24 Multiple regression analysis showed that the younger the age and the larger the ILM flap, the more it tends to contract, and the contraction of the ILM flap may lead to a decrease in postoperative visual function. Studies of epiretinal membrane (ERM) recurrence have shown that ILM peeling reduces ERM recurrence, possibly because of the presence of ERM fragments on the surface of the ILM and the fact that the ILM serves as the basis for cell proliferation and may induce cell proliferation and epiretinal membrane recurrence.^25–28 In this study, histopathological examination revealed that cells adhered to the surface of the ILM that faced the vitreous side after inversion, suggesting that cell proliferation occurred using the ILM flap as a scaffold by a mechanism similar to that of ERM recurrence, resulting in contraction of the ILM flap. As in the case of ERM recurrence, peeling of the ILM flap can be expected to improve visual function in patients with visual impairment.¹³ The limitations of this study are the small number of cases included and the relatively short observation period of six months. It has been considered that morphological changes of the ILM flap could occur and should be examined over a long period of time.

In conclusion, vitrectomy using the inverted ILM flap technique yielded good anatomical and functional results. However, there are cases in which ILM flap contraction is observed during the postoperative period. Especially in cases with younger individuals, cases with large flaps, cases where the degree of contraction of the ILM flap tends to be large, and when re-operation may be required. The ILM flap technique is a relatively new technique, and it is important to find a safe protocol that can be reliably performed, and can facilitate the maintenance of good visual function for a long period of time.

Patients

This study included patients who underwent vitreous surgery for MH at the Hayashi Eye Hospital between August 2018 and February 2020, in which the MH was treated by vitrectomy with coverage of a single ILM flap and had a follow-up period of at least six months after vitrectomy. We conducted this prospective observational case series study in accordance with the Declaration of Helsinki and received approval from the Ethics Committee of the Hayashi Eye Hospital. All patients who participated in the study gave written informed consent after receiving an explanation of the nature of the study before inclusion in the study. The ILM flap technique was indicated when the hole diameter was greater than 400 µm, in the case of idiopathic MHs and myopic MHs, with an axial length of ≥ 26 mm. Eyes with diabetic retinopathy, retinal vein occlusion, a history of pars plana vitrectomy, or uveitis, were excluded.

Surgical procedure

All patients underwent surgery by a single surgeon (A.H.) following induction of local sub-Tenon’s anesthesia, as previously reported.^13,29 Phacoemulsification and aspiration (PEA) and 3-piece hydrophobic acrylic intraocular lens (IOL) implantation were performed in 15 patients with cataracts. Three patients had a clear lens that did not require cataract surgery. The remaining five patients had already undergone cataract surgery. Subsequently, we performed a 25-gauge pars plana vitrectomy using a wide-angle viewing system (Fig. 6 and supplemental video 3). After core vitrectomy, a posterior vitreous detachment was created in cases where posterior vitreous detachment had not occurred. After staining the macula with Brilliant Blue G solution,³⁰ the ILM was peeled at the size of one disc diameter around the MH (Fig. 6A). Next, an ILM flap was created on the temporal side of the macula to sufficiently cover the hole (Fig. 6B), and the flap was stretched and covered over the hole using dispersive ophthalmic viscosurgical devices (Fig. 6C). Peripheral vitrectomy was then performed while monitoring for peripheral retinal tears. Finally, fluid-air exchange and air tamponade were performed (Fig. 6D). The patient was instructed to remain in the prone position for 1–3 days postoperatively.

Examination

Best-corrected visual acuity (BCVA) was measured using the Landolt chart at various time points including, before surgery, immediately after the disappearance of air in the eye, and at three post-operative points (one, three, and six months). BCVA measurements were converted to the logarithm of the minimum angle of resolution (logMAR) for analysis. All patients underwent retinal imaging using a sweeping light source OCT (Plex Elite 9000; Carl Zeiss Meditec Inc., Dublin, CA, USA). An image with a signal strength of 7 or higher (up to 10) was defined as a suitable. Horizontal and vertical HD scans (HD Spotlight 1 with a measurement width of 16 mm, 0°, and 90°) were used to measure the MH diameter and to analyze the continuity of the external limiting membrane (ELM) and ellipsoid zone. Cube scans (12 mm × 12 mm, 800 × 800 pixels) were used to measure the size of the ILM flap. En face structural slabs of the vitreoretinal interface were created from the cube scans by automated segmentation (133 µm above the ILM layer as the inner boundary and 33 µm below the ILM layer as the outer boundary) allowing visualization of the ILM flap boundary. The en face image obtained to measure the size of the ILM flap was saved as a TIFF file and imported with ImageJ software (https://imagej.nih.gov/ij/; provided in the public domain by the National Institutes of Health, Bethesda, MD) ³¹. The boundaries of the ILM flaps were manually traced and segmented using a graphics tablet (Wacom Cintiq 16; Wacom Co., Ltd., Kazo, Saitama, Japan), and the flap area was measured using the measurement features built into ImageJ.

Before the measurement of the ILM flap area, a reconstructed image of the retinal surface was created using 3D reconstruction software to verify whether the contour of the ILM flap, obtained from the en face image of OCT, was accurate. The captured data from the cube scan were exported as a movie file, processed, and saved as a stack image using ImageJ. The data were further transferred to the 3D visualization/analysis software (Amira v6.0.1; Thermo Fisher Scientific, Waltham, MA), and a 3D image of the macular retina was created. The obtained images showed the unevenness of the retinal surface from various directions, and the contour of the ILM was confirmed to be consistent with the contour of the ILM flap obtained from the en face image (supplemental video 1).

The following four issues were examined: postoperative MH status (presence or absence of MH closure and the continuity of external limiting membrane and ellipsoid zone), comparison of BCVA before and six months after surgery, comparison of the ILM flap area at one month and six months postoperatively, and analysis of preoperative clinical data related to changes in the ILM flap size.

Statistical analysis

In comparing the clinical characteristics of patients with idiopathic MH and myopic MH, we used an unpaired t-test for patient age, MH size, preoperative BCVA, and axial length, and a Fisher's exact probability test for sex. Comparison of pre-and postoperative BCVA was performed using the paired t-test, and the ILM flap area was compared using en face images at the vitreoretinal interface and tested using the Wilcoxon signed-rank test. The Spearman’s rank correlation coefficient was calculated for the correlation between postoperative BCVA after six months and preoperative factors including patients age, sex, MH size, preoperative BCVA and axial length, and the size of the ILM flap at one month. The factors related to ILM flap contraction were analyzed by multiple linear regression analysis with the objective variables being the contraction rate of the ILM flap and the preoperative clinical data selected by the stepwise method as explanatory variables. All statistical analyses were performed using JMP® Pro 15 statistical software (SAS Institute, Inc., Cary, NC, USA) or Prism 7 for Mac OS X (version 7.0b, GraphPad Software, Inc., San Diego, CA, USA), and statistical significance was set at P < 0.05.

Acknowledgements: The authors thank Editage (www. editage. jp) for English language editing.

Author contributions: A.H. designed the study and wrote the main manuscript text. K.M. contributed to data collection and interpretation. K.H. contributed to analysis and interpretation of data, and assisted in the preparation of the manuscript. All authors approved the final version of the manuscript.

Competing interests: The authors (AH, KM and KH) declare that they have no competing interests

Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Funding: This work was supported by JSPS KAKENHI, Grant Number JP 19K10003.

Author information

Affiliations:

Hayashi Eye Hospital

4-23-35, Hakataekimae, Fukuoka-City, Fukuoka 812-0011, Japan

Department of Anatomy, Kurume University School of Medicine

67 Asahi-machi, Kurume-City, Fukuoka 830-0011, Japan

Corresponding author: Akira Hirata

Funding: This work was supported by JSPS KAKENHI, Grant Number JP 19K10003.

1 Kelly, N. E. & Wendel, R. T. Vitreous surgery for idiopathic macular holes. Results of a pilot study. Arch Ophthalmol 109, 654-659, doi:10.1001/archopht.1991.01080050068031 (1991).

2 Eckardt, C., Eckardt, U., Groos, S., Luciano, L. & Reale, E. Removal of the internal limiting membrane in macular holes. Clinical and morphological findings. Ophthalmologe 94, 545-551, doi:10.1007/s003470050156 (1997).

3 Kumagai, K. et al. Vitreous surgery with and without internal limiting membrane peeling for macular hole repair. Retina 24, 721-727, doi:10.1097/00006982-200410000-00006 (2004).

4 Michalewska, Z., Michalewski, J., Adelman, R. A. & Nawrocki, J. Inverted internal limiting membrane flap technique for large macular holes. Ophthalmology 117, 2018-2025, doi:10.1016/j.ophtha.2010.02.011 (2010).

5 Boninska, K., Nawrocki, J. & Michalewska, Z. Mechanism of "Flap Closure" after the Inverted Internal Limiting Membrane Flap Technique. Retina 38, 2184-2189, doi:10.1097/IAE.0000000000001861 (2018).

6 Matsumura, T. et al. Comparison of the Inverted Internal Limiting Membrane Flap Technique and the Internal Limiting Membrane Peeling for Macular Hole with Retinal Detachment. PLoS One 11, e0165068, doi:10.1371/journal.pone.0165068 (2016).

7 Takahashi, H. et al. Inverted internal limiting membrane flap technique for treatment of macular hole retinal detachment in highly myopic eyes. Retina 38, 2317-2326, doi:10.1097/IAE.0000000000001898 (2018).

8 Kuriyama, S. et al. Efficacy of inverted internal limiting membrane flap technique for the treatment of macular hole in high myopia. Am J Ophthalmol 156, 125-131 e121, doi:10.1016/j.ajo.2013.02.014 (2013).

9 Baba, R. et al. Efficacy of the Inverted Internal Limiting Membrane Flap Technique with Vitrectomy for Retinal Detachment Associated with Myopic Macular Holes. Retina 37, 466-471, doi:10.1097/IAE.0000000000001211 (2017).

10 Hu, X. T., Pan, Q. T., Zheng, J. W. & Zhang, Z. D. Foveal microstructure and visual outcomes of myopic macular hole surgery with or without the inverted internal limiting membrane flap technique. Br J Ophthalmol 103, 1495-1502, doi:10.1136/bjophthalmol-2018-313311 (2019).

11 Chen, S. N., Hsieh, Y. T. & Yang, C. M. Multiple free internal limiting membrane flap insertion in the treatment of macular hole-associated retinal detachment in high myopia. Ophthalmologica 240, 143-149, doi:10.1159/000487337 (2018).

12 Michalewska, Z., Michalewski, J., Dulczewska-Cichecka, K. & Nawrocki, J. Inverted internal limiting membrane flap technique for surgical repair of myopic macular holes. Retina 34, 664-669, doi:10.1097/IAE.0000000000000042 (2014).

13 Hirata, A., Takano, A., Kawaji, T. & Nakamura, K. I. Macular pucker formation after macular hole surgery with inverted internal limiting membrane flap technique and silicone oil tamponade. Am J Ophthalmol Case Rep 19, 100847, doi:10.1016/j.ajoc.2020.100847 (2020).

14 Shiode, Y. et al. The role of inverted internal limiting membrane flap in macular hole closure. Invest Ophthalmol Vis Sci 58, 4847-4855, doi:10.1167/iovs.17-21756 (2017).

15 Baumann, C. et al. Effect of Inverted Internal Limiting Membrane Flap on Closure Rate, Postoperative Visual Acuity, and Restoration of Outer Retinal Layers in Primary Idiopathic Macular Hole Surgery. Retina, doi:10.1097/IAE.0000000000002707 (2019).

16 Iwasaki, M., Kinoshita, T., Miyamoto, H. & Imaizumi, H. Influence of inverted internal limiting membrane flap technique on the outer retinal layer structures after a large macular hole surgery. Retina 39, 1470-1477, doi:10.1097/IAE.0000000000002209 (2019).

17 Rossi, T. et al. Macular hole closure patterns associated with different internal limiting membrane flap techniques. Graefes Arch Clin Exp Ophthalmol 255, 1073-1078, doi:10.1007/s00417-017-3598-9 (2017).

18 Faria, M. Y. et al. Inverted Internal Limiting Membrane Flap Techniques and Outer Retinal Layer Structures. Retina, doi:10.1097/IAE.0000000000002607 (2019).

19 Michalewska, Z., Michalewski, J., Dulczewska-Cichecka, K., Adelman, R. A. & Nawrocki, J. Temporal inverted internal limiting membrane flap technique versus classic inverted internal limiting membrane flap technique: a comparative study. Retina 35, 1844-1850, doi:10.1097/IAE.0000000000000555 (2015).

20 Gekka, T. et al. Pedicle Internal Limiting Membrane Transposition Flap Technique for Refractory Macular Hole. Ophthalmic Surg Lasers Imaging Retina 46, 1045-1046, doi:10.3928/23258160-20151027-10 (2015).

21 Chen, S. N. Large semicircular inverted internal limiting membrane flap in the treatment of macular hole in high myopia. Graefes Arch Clin Exp Ophthalmol 255, 2337-2345, doi:10.1007/s00417-017-3808-5 (2017).

22 Aurora, A., Seth, A. & Sanduja, N. Cabbage leaf inverted flap ILM peeling for macular hole: A novel technique. Ophthalmic Surg Lasers Imaging Retina 48, 830-832, doi:10.3928/23258160-20170928-08 (2017).

23 Tabandeh, H., Morozov, A., Rezaei, K. A. & Boyer, D. S. Superior wide-base internal limiting membrane flap transposition for macular holes: flap status and outcomes. Ophthalmol Retina 5, 317-323, doi:10.1016/j.oret.2020.12.003 (2021).

24 Takai, Y., Tanito, M., Sugihara, K. & Ohira, A. The role of single-layered flap in temporal inverted internal limiting membrane flap technique for macular holes: pros and cons. J Ophthalmol 2019, 5737083, doi:10.1155/2019/5737083 (2019).

25 De Novelli, F. J. et al. Recurrence rate and need for reoperation after surgery with or without internal limiting membrane removal for the treatment of the epiretinal membrane. Int J Retina Vitreous 3, 48, doi:10.1186/s40942-017-0101-z (2017).

26 Sandali, O. et al. Epiretinal membrane recurrence: incidence, characteristics, evolution, and preventive and risk factors. Retina 33, 2032-2038, doi:10.1097/IAE.0b013e31828d2fd6 (2013).

27 Kwok, A., Lai, T. Y. & Yuen, K. S. Epiretinal membrane surgery with or without internal limiting membrane peeling. Clin Exp Ophthalmol 33, 379-385, doi:10.1111/j.1442-9071.2005.01015.x (2005).

28 Gandorfer, A. et al. Residual cellular proliferation on the internal limiting membrane in macular pucker surgery. Retina 32, 477-485, doi:10.1097/IAE.0b013e3182246e2a (2012).

29 Hirata, A., Hayashi, K., Murata, K. & Nakamura, K. I. Removal of choroidal neovascular membrane in a case of macular hole after anti-VEGF therapy for age-related macular degeneration. Am J Ophthalmol Case Rep 9, 14-17, doi:10.1016/j.ajoc.2017.12.003 (2018).

30 Enaida, H. et al. Preclinical investigation of internal limiting membrane staining and peeling using intravitreal brilliant blue G. Retina 26, 623-630, doi:10.1097/01.iae.0000236470.71443.7c (2006).

31 Schneider, C. A., Rasband, W. S. & Eliceiri, K. W. NIH Image to ImageJ: 25 years of image analysis. Nat Methods 9, 671-675, doi:10.1038/nmeth.2089 (2012).

32 Hirata, A., Murata, K., Hayashi, K. & Nakamura, K. I. Three-dimensional analysis of peeled internal limiting membrane using focused ion beam/scanning electron microscopy. Transl Vis Sci Technol 7, 15, doi:10.1167/tvst.7.1.15 (2018).

No competing interests reported.

Supplementalvideo1.mp4
Supplemental video 1 OCT En Face images and corresponding 3-dimentional reconstructed images at 1 and 6 months postoperatively. The contours of the internal limiting membrane (ILM) obtained from the en face image were consistent with the contours of the ILM flap images created by 3D reconstruction software from the stacked images of the cube scan.
Supplementalvideo2.mp4
Supplemental video 2 3D reconstructed image of the peeled internal limiting membrane (ILM) flap The upper part of the image obtained by focused ion beam-equipped scanning electron microscopy shows the original retinal side of the ILM, which has been inverted after surgery and is facing the vitreous side; multiple cells (purple, pink, and light blue) are attached to the surface of the ILM (green), and cell-cell adhesion is also observed; the fibrous component (yellow) is also seen on the surface of the ILM.
Supplementalvideo3.mp4
Supplemental video 3 Intraoperative findings demonstrating surgical technique After staining the macula with Brilliant Blue G solution, the internal limiting membrane (ILM) peeling around the macular hole (MH) was performed. Then, an ILM flap was created on the temporal side of the macula and covered over the hole using dispersive ophthalmic viscosurgical devices. Finally, fluid-air exchange and air tamponade were performed.

Download PDF

Editorial decision: Major revision
02 Aug, 2021
Reviewers agreed at journal
31 Jul, 2021
Reviews received at journal
29 Jul, 2021
Reviewers agreed at journal
24 Jul, 2021
Reviewers invited by journal
22 Jul, 2021
Editor assigned by journal
22 Jul, 2021
Editor invited by journal
20 Jun, 2021
Submission checks completed at journal
16 Jun, 2021
First submitted to journal
12 Jun, 2021

You are reading this latest preprint version

Contractility of inverted internal limiting membrane flap after vitrectomy for macular hole

Status:

Version 1

Abstract

Figures

Introduction

Results

Discussion

Patients And Methods

Patients

Surgical procedure

Examination

Statistical analysis

Declarations

References

Additional Declarations

Supplementary Files

Status:

Version 1