Macular hole surgery with triamcinolone acetonide-assisted internal limiting membrane peeling: one-year results

Proof-of-Concept Analysis of a Deep Learning Model to Conduct Automated Segmentation of OCT Images for Macular Hole Volume

BACKGROUND AND OBJECTIVE

To determine whether an automated artificial intelligence (AI) model could assess macular hole (MH) volume on swept-source optical coherence tomography (OCT) images.

PATIENTS AND METHODS

This was a proof-of-concept consecutive case series. Patients with an idiopathic full-thickness MH undergoing pars plana vitrectomy surgery with 1 year of follow-up were considered for inclusion. MHs were manually graded by a vitreoretinal surgeon from preoperative OCT images to delineate MH volume. This information was used to train a fully three-dimensional convolutional neural network for automatic segmentation. The main outcome was the correlation of manual MH volume to automated volume segmentation.

RESULTS

The correlation between manual and automated MH volume was R² = 0.94 (n = 24). Automated MH volume demonstrated a higher correlation to change in visual acuity from preoperative to the postoperative 1-year time point compared with the minimum linear diameter (volume: R² = 0.53; minimum linear diameter: R² = 0.39).

CONCLUSION

MH automated volume segmentation on OCT imaging demonstrated high correlation to manual MH volume measurements. [Ophthalmic Surg Lasers Imaging Retina. 2022;53(4):208-214.].

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

Purpose

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

Method

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

Results

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

Conclusions

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

Long-Term Outcomes of Macular Hole Repair with Triamcinolone Acetonide Visualization

Purpose

To evaluate the long-term anatomic and visual outcomes of macular hole (MH) repair utilizing triamcinolone acetonide (TA) visualization of the internal limiting membrane (ILM) treated at a tertiary care retina practice.

Methods

Retrospective chart review of eyes undergoing MH repair with ILM peel utilizing TA visualization followed by gas tamponade and facedown positioning between 2014 and 2020. Pre- and post-operative visual acuity (VA), IOP, and anatomic closure based on optical coherence tomography were documented.

Results

Seventy-eight eyes were followed for 2.3±0.2 years after primary repair with anatomic closure in 73 (94%) eyes at their final visit and excluding eyes with pathologic myopia, 97%, and for stage 2 and small MHs, 100%. In all eyes, VA significantly improved from 0.97±0.04 (Snellen: 20/187) to 0.66±0.06 (20/91) logMAR (p < 0.0001). There were 16 eyes with 4 years of follow-up, 10 (63%) eyes achieving a VA ≥20/30 at that follow-up visit. Stage 2 and 3 MHs had significantly greater improvements in VA than Stage 4 MHs, −0.46 ± 0.06 versus −0.11 ± 0.11 logMAR (p = 0.021). Of the 13 (17%) eyes with recurrent MHs, 6 (46%) had pathologic myopia and 8 (61.5%) had associated cystoid macular edema. Cataract progression was reported in 52 (96%) phakic eyes and 2 eyes required Ahmed valve placement for management of pre-existing glaucoma.

Conclusion

Long-term results of MH repair with TA for ILM visualization demonstrate that it is safe and effective. Visual acuity continued to improve throughout the follow-up. Pre-existing glaucoma may progress and recurrence is associated with pathologic myopia and macular edema.

Outcomes of 4 surgical adjuvants used for internal limiting membrane peeling in macular hole surgery: a systematic review and network Meta-analysis

AIM

To compare the outcomes of four adjuvants used for internal limiting membrane (ILM) peeling in macular hole surgery, including indocyanine green (ICG), brilliant blue G (BBG), triamcinolone (TA) and trypan blue (TB), through systematic review and random-effects Bayesian network Meta-analysis.

METHODS

PubMed, Cochrane library databases and Web of Science were searched until August 2018 for clinical trials comparing the above four adjuvants. ORs for postoperative best corrected visual acuity (BCVA) improvement and primary macular hole closure rates were compared between the different adjuvants.

RESULTS

Twenty-seven eligible articles were included. For postoperative BCVA improvement, results of BBG-assisted peeling were significantly more favorable than those of ICG (WMD 0.08, 95% credible interval 0.01-0.16) and TA ranked highest. No significant differences were found between any other two groups in postoperative BCVA improvement. For postoperative primary macular hole closure rates, BBG ranked highest. However, no significant differences were shown between any two groups.

CONCLUSION

TA and BBG are the optimum adjuvants for achieving postoperative BCVA improvement macular hole surgery with adjuvant-assisted ILM peeling. Among all adjuvants, the use of BBG is associated with the highest postoperative macular hole closure rate.

Internal limiting membrane peeling with different dyes in the surgery of idiopathic macular hole: a systematic review of literature and network Meta-analysis

AIM

To evaluate the effect of internal limiting membrane (ILM) peeling with indocyanine green (ICG), brilliant blue G (BBG), triamcinolone acetonide (TA), trypan blue (TB), or without dye for the treatment of idiopathic macular hole (IMH).

METHODS

A search was conducted using PubMed, EMBASE, and CENTRAL (Cochrane Central Register of Controlled Trials) for related studies published before October 2018.

RESULTS

A total of 29 studies and 2514 eyes were included in this network Meta-analysis. For IMH closure, the rank from the best to the worse treatment was: BBG, TB, TA, ICG, and no dye. There was a significant difference in postoperative IMH closure rate between BBG and no dye. The rank of the best to the worse treatment to improve visual acuity was: BBG, TB, no dye, TA, and ICG. The improvement rate of visual acuity after using BBG was significantly higher than ICG. The improvement rate of visual acuity was more favorable with TB than ICG, TA, and no dye.

CONCLUSION

BBG can contribute to better anatomical and functional outcomes compared to other dyes for ILM peeling in patients with IMH. The results show that the best treatment of ILM peeling with dyes is BBG.

Vital Dyes in Vitreomacular Surgery

Vital dyes contain complex molecules with chromophores that stain living tissues and have greatly enhanced identification and removal of transparent vitreoretinal tissues during surgery. Several "chromovitrectomy" dyes are frequently used by vitreoretinal specialists, including indocyanine green, trypan blue, brilliant blue G, and triamcinolone acetonide; other dyes are also under investigation. Trypan Blue was approved by the U.S. Food and Drug Administration (FDA) for epiretinal membrane removal, and preservative-free triamcinolone acetonide was approved by the FDA for intraocular use. However, currently available chromovitrectomy dyes have their limitations, and of particular concern for some of them is the possibility for acute and chronic toxicity to the neurosensory retina and retinal pigmented epithelium. The potentially irreversible acute toxicity and other limitations, such as lack of long-term safety profiles, highlight the need for further advancements. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:788-798.].

Anatomical Changes of Full-Thickness Macular Hole Documented by Microscope-Integrated Spectral-Domain Optical Coherence Tomography

BACKGROUND AND OBJECTIVE

To evaluate anatomical changes of idiopathic macular hole (MH) after internal limiting membrane removal and after passive suction at the hole's borders using microscope-integrated intraoperative optical coherence tomography (iOCT).

PATIENTS AND METHODS

Five eyes of five subjects with full-thickness idiopathic MH underwent phacoemulsification, intraocular lens implantation, pars plana vitrectomy, and internal limiting membrane (ILM) removal. iOCT was performed after ILM removal and after passive suction at the hole's borders.

RESULTS

iOCT showed decreased MH diameter after ILM removal in all cases. Passive suction achieved complete apposition of borders. All cases presented successful postsurgical closure.

CONCLUSIONS

iOCT provides anatomical information during MH surgery that may impact surgical decision-making by allowing a real-time evaluation of structures. iOCT with preservative-free triamcinolone acetonide enhanced ILM visualization. Its use is superior to iOCT alone for the identification of vitreomacular interface structures. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e105-e111.].

A Review of Surgical Outcomes and Advances for Macular Holes

The surgical outcomes of macular holes (MHs) have improved greatly in recent years. The closure rate is as high as 90-100%, but the outcomes of some special types of MHs remain unsatisfactory. Internal limiting membrane (ILM) peeling dramatically improves the anatomic success rate, but recent studies have found that it could also cause mechanical and subclinical traumatic changes to the retina. Dyes are widely used, and apart from indocyanine green (ICG), the toxicities of other dyes require further research. Face-down posturing is necessary for MHs larger than 400 μm, and the duration of this posture is determined by the type of tamponade and the case. The ellipsoid zone has been shown to be highly correlated with visual outcome and recovery. New surgical methods include the inverted ILM flap technique and the ILM abrasion technique. However, they require further research to determine their effectiveness.

Comparisons of retinal nerve fiber layer thickness after indocyanine green, brilliant blue g, or triamcinolone acetonide-assisted macular hole surgery

Purpose. To compare the postoperative changes of the retinal nerve fiber layer (RNFL) thickness in patients with macular holes (MHs) treated with vitrectomy with indocyanine green- (ICG-), brilliant blue G- (BBG-), or triamcinolone acetonide- (TA-)assisted internal limiting membrane (ILM) peeling. Methods. Sixty-one eyes of 61 consecutive patients with MHs were studied. Each eye was randomly selected to undergo either ICG- (n = 18), BBG- (n = 21), or TA-assisted (n = 22) ILM peeling. The circumferential retinal nerve fiber layer (RNFL) thickness was determined by spectral-domain optical coherence tomography (SD-OCT) before and 1, 3, 6, 9, and 12 months postoperatively. The mean overall and the sectoral thicknesses of the RNFL were obtained for each group. Results. A transient increase of the RNFL thickness was seen in the mean overall and sectoral thicknesses except for the nasal/inferior sector at 1 month after surgery for the three groups. Then, the thickness gradually decreased and returned to the baseline level in all sectors except for the nasal/inferior sector. The differences in the RNFL thickness among the groups were not significant for at least 12 months postoperatively. Conclusions. The degree of change of the RNFL thickness was not significantly related to the type of vital stain used during MH surgery.

Effect of optical coherence tomography scan pattern and density on the detection of full-thickness macular holes

PURPOSE

To evaluate the impact of different scan patterns and scan densities on small full-thickness macular hole (MH) detection.

DESIGN

Retrospective cross-sectional analysis.

METHODS

Analysis was performed on 25 eyes from 24 patients with full-thickness MHs imaged with the Heidelberg Spectralis HRA+OCT. Included eyes underwent concurrent imaging with a standard (61-line) raster volume and a 24-line radial pattern. A 6-line radial scan pattern was extrapolated from the higher-density radial pattern. Comparisons of the missed hole rate as well as the proportion of individual B-scans demonstrating a full-thickness defect (termed "full-thickness detection index") were carried out for the 3 scan patterns. Additionally, qualitative and quantitative hole parameters were evaluated to identify factors associated with "missed" holes.

RESULTS

Full-thickness defects were missed at substantially higher rates using both standard raster volume (20.0%, 90% confidence interval [CI] 8.2%-37.5%) and 6-line radial scanning (12.0%, 90% CI 3.7%-30.4%) when compared to 24-line radial scanning (0% for both comparisons). Full-thickness detection indices were significantly higher for both radial scan patterns when compared to raster scanning (P < .001 for both comparisons). Missed holes were smaller and commonly associated with prehole flaps.

CONCLUSION

High-density radial scanning demonstrated superior detection rates of small full-thickness MHs compared to standard raster volume scanning. This finding may be attributable to the greater foveolar scan density attained with radial scan patterns. Failure to utilize radial scanning in the setting of suspected macular holes may lead to a delay in surgical treatment, with attendant worse anatomic and visual outcomes.

Comparisons of cone electroretinograms after indocyanine green-, brilliant blue G-, or triamcinolone acetonide-assisted macular hole surgery

PURPOSE

To compare the function of retinal ganglion cells (RGCs) using the photopic negative response (PhNR) in patients who had undergone indocyaine green (ICG)-assisted, brilliant blue G (BBG)-assisted, or triamcinolone acetonide (TA)-assisted internal limiting membrane (ILM) peeling during macular hole (MH) surgery.

METHODS

Forty-eight eyes of 48 patients with a macular hole were randomly divided into those undergoing ICG-assisted, BBG-assisted, or TA-assisted vitrectomy (n = 16 for each group). Full-field cone ERGs were recorded before and 1, 3, 6, 9, and 12 months postoperatively. The amplitudes and implicit times of the a-waves and b-waves and the amplitudes of the oscillatory potentials (OPs) and PhNRs were measured. The mean deviations (MDs) of standard automated perimetry and the best-corrected visual acuity (BCVA) were measured. The circumferential retinal nerve fiber layer (RNFL) thickness was evaluated by SD-OCT.

RESULTS

All macular holes were closed with a significant improvement of the BCVA and MD without differences among the groups. There was no significant difference between the preoperative and postoperative RNFL thickness. The implicit times of the a-waves and b-waves were significantly prolonged, and the ΣOPs amplitude was significantly decreased postoperatively in all groups. These ERG changes were not significantly different among the groups. The postoperative PhNR amplitudes were significantly lower in the ICG group than in the BBG or TA group.

CONCLUSIONS

The results indicate that the PhNR may detect subclinical impairments of RGCs caused by the possible toxic effect of ICG. This finding adds to the data that BBG and TA may be safer than ICG for use during MH surgery.

Predicting visual outcome following surgery for idiopathic macular holes

Since Kelly and Wendel [Arch Ophthalmol 1991;109:654-659] first reported successfully treating macular holes (MHs) using pars plana vitrectomy in 1991, MH surgery has been constantly improved. For example, introducing the removal of the internal limiting membrane considerably increased the closure rate of MHs, and the advent of microincision vitrectomy surgery reduced surgical trauma and decreased patient discomfort after surgery. As modern MH surgery can achieve a higher anatomical success rate and alleviate patients' postoperative distress, postoperative visual outcomes have lately become the primary concern. Informing patients of the expected visual acuity and visual improvement before surgery is ideal, but predicting postoperative visual outcomes is difficult because a large number of factors are associated with them. In this paper, we review previous studies and provide accumulating evidence for the relationship between individual prognostic factors and visual outcomes after MH surgery.

Indocyanine green-assisted internal limiting membrane peeling in macular hole surgery: a meta-analysis

Background

The opinion of application of indocyanine green (ICG) in the macular hole surgery was contradictory. Here we conducted a meta-analysis to evaluate the effect of in internal limiting membrane (ILM) peeling for macular hole surgery.

Methods and Findings

We searched electronic databases for comparative studies published before July 2012 of ILM peeling with and without ICG. Twenty-two studies including 1585 eyes were included. Visual acuity (VA) improvement, including the postoperative rate of ≥20/40 VA gained (OR, 0.65; 95% CI, 0.43 to 0.97; P = 0.033) and increased LogMAR (WMD, −0.09; 95% CI, −0.16 to −0.02; P = 0.011), was less in the ICG group. The risk of visual field defects was greater in the ICG group than in the non-ICG group. There was no significant difference in the rate of anatomical outcomes between ILM peeling procedures performed with and without ICG. RPE changes and other postoperative complications were not significantly different between the ICG and non-ICG groups. An additional analysis showed that the VA improvement of the ICG group was less than the non-ICG group only within the first year of follow up. A subgroup analysis showed that the rate of VA improvement was lower in the ICG group than in other adjuncts group. A higher rate of secondary closure and less VA improvement were observed in a high proportion (>0.1%) of the ICG group. A sensitivity analysis after the randomized-controlled trials were excluded from the meta-analysis demonstrated no differences compared with the overall results.

Conclusions

This meta-analysis demonstrated that there is no evidence of clinical superiority in outcomes for ICG-assisted ILM peeling procedure over the non-ICG one. The toxicity of ICG should be considered when choosing the various staining methods.

Techniques, rationale, and outcomes of internal limiting membrane peeling

BACKGROUND

The internal limiting membrane represents the structural interface between the retina and the vitreous and has been postulated to serve several essential functions. Recently, internal limiting membrane peeling has been used in the treatment of a variety of retinal disorders. We review the history, techniques, rationale, and outcomes of internal limiting membrane peeling.

METHODS

A review of the literature.

RESULTS

Internal limiting membrane peeling has been used to successfully treat a variety of retinal disorders including macular hole, epiretinal membrane, diabetic macular edema, retinal vein occlusion, and others.

CONCLUSION

Internal limiting membrane peeling may serve as an important component in the armamentarium of retinal surgery.

Unanticipated vision loss after pars plana vitrectomy

Although advances in vitreoretinal surgical techniques and technology have helped to minimize the risks associated with surgical manipulation of the retina, retinal pigment epithelium, and optic nerve, unanticipated or unexplained visual loss still occurs. We review causes of vision loss encountered after pars plana vitrectomy, including retinal toxicities, vascular events, and optic neuropathies, and we suggest strategies to limit or prevent them.

Toxicity profiles of subretinal indocyanine green, Brilliant Blue G, and triamcinolone acetonide: a comparative study

BACKGROUND

This study introduces a novel porcine model to examine the histopathological and electrophysiological consequences of retinotoxicity exerted by dyes commonly used for internal limiting membrane (ILM) staining.

METHODS

Indocyanine green (ICG) 0.5 mg/ml, Brilliant Blue G (BBG) 0.25 mg/ml and triamcinolone acetonide (TA) 13 mg/ml was injected subretinally in 12 vitrectomized pig eyes. At 6 weeks, retinas were examined by multifocal electroretinography (mfERG), ophthalmoscopy, fluorescein angiograpy, histopathology, and apoptosis assay.

RESULTS

mfERG responses were significantly lower in ICG-injected eyes than in healthy fellow eyes (p = 0.039). The ratio between injected eyes and healthy fellow eyes was lower in the ICG group than in the BBG (p = 0.009) and TA group (p = 0.025). No difference between BBG and TA existed. All retinas were reattached, and fluorescein angiographies showed a window defect corresponding to the injected areas but no blood-retina barrier break-down. Histopathology confirmed damage to the outer retina after ICG, but not after BBG and TA. No apoptosis was found at 6 weeks.

CONCLUSIONS

Subretinal ICG induces histological and functional damage to the retina, suggesting that ICG should be used with caution in macular hole surgery, where subretinal migration can occur. In contrast, BBG and TA appear safe after subretinal injection.

Outcomes of 23-gauge pars plana vitrectomy and internal limiting membrane peeling with brilliant blue in macular hole

Purpose:

The evaluation of anatomic and visual outcomes in macular hole cases treated with internal limiting membrane (ILM) peeling, brilliant blue (BB), and 23-gauge pars plana vitrectomy (PPV).

Materials and methods:

Fifty eyes of 48 patients who presented between July 2007 and December 2009 with the diagnosis of stage 2, 3, or 4 macular holes according to Gass Classification who had undergone PPV and ILM peeling were included in this study. Pre- and postoperative macular examinations were assessed with spectral-domain optical coherence tomography. 23 G sutureless PPV and ILM peeling with BB was performed on all patients.

Results:

The mean age of patients was 63.34 ± 9.6 years. Stage 2 macular hole was determined in 17 eyes (34%), stage 3 in 24 eyes (48%), and stage 4 in 9 eyes (18%). The mean follow-up time was 13.6 ± 1.09 months. Anatomic closure was detected in 46/50 eyes (92%), whereas, in four cases, macular hole persisted and a second operation was not required due to subretinal fluid drainage. At follow-up after 2 months, persistant macular hole was detected in one case and it was closed with reoperation. At 12 months, an increase in visual acuity in 41 eyes was observed, while it remained at the same level in six eyes. In three eyes visual acuity decreased. There was a postoperative statistically significant increase in visual acuity in stage 2 and 3 cases (P < 0.05), however, no increase in visual acuity in stage 4 cases was observed.

Conclusion:

PPV and ILM peeling in stage 2, 3, and 4 macular hole cases provide successful anatomic outcomes, however, in delayed cases, due to photoreceptor loss, it has no effect on functional recovery. BB, used for clarity of ILM, may be beneficial due to its low retinal toxicity.

Comparative evaluation of anatomical and functional outcomes using brilliant blue G versus triamcinolone assisted ILM peeling in macular hole surgery in Indian population

PURPOSE

To compare anatomical and functional outcomes using brilliant blue G (BBG) vs triamcinolone acetonide (TA)-assisted ILM peeling in macular hole surgery (MHS).

STUDY DESIGN

Simple, comparative, retrospective, non-randomised, interventional single-centre study.

METHODS

Ninety-four eyes of 94 patients with idiopathic macular holes (≥ stage 2) who underwent MHS at our centre were included. Patients with failed macular holes, post-traumatic macular holes, history of previous vitreoretinal surgery, high myopia (6 dioptres or more) or any other macular pathology potentially limiting visual acuity, such as diabetic retinopathy or age-related macular degeneration, were excluded. An OCT evaluation of hole status was followed by pars plana vitrectomy for each of these eyes. Those who underwent TA-assisted ILM peeling were considered as group 1 and those with BBG-assisted ILM peeling were considered as group 2. Primary outcome measures included anatomical hole closure and functional success in terms of change in visual acuity of ≥2 LogMAR lines. Various preoperative factors were also evaluated.

RESULTS

Anatomical hole closure was achieved in 85 eyes (90.43%) and visual gain in 78 eyes (82.9%). Mean postoperative follow-up duration was 16.14 ± 1.95 months. No significant difference was found in anatomical and functional success between the two groups. Group 1 had a significantly higher incidence of postoperative glaucoma. Duration of symptoms of <12 months (p = 0.004) and preoperative visual acuity ≤1.0 LogMAR were related to anatomical success. However, greater visual gain was found in patients with chronic holes (≥12 months) (p = 0.046) and poor preoperative visual acuity (>1.0 LogMAR) (p = 0.001).

CONCLUSION

BBG-assisted ILM peeling offers an effective alternative to triamcinolone, with the added advantage of marked enhancement of vitreoretinal interface contrast with comparable hole closure rates and visual outcomes.

Value of internal limiting membrane peeling in surgery for idiopathic macular hole and the correlation between function and retinal morphology

Idiopathic macular hole is characterized by a full thickness anatomic defect in the foveal retina leading to loss of central vision, metamorphopsia and a central scotoma. Classic macular hole surgery consists of vitrectomy, posterior vitreous cortex separation and intraocular gas tamponade, but during the past decade focus has especially been on internal limiting membrane (ILM) peeling as adjuvant therapy for increasing closure rates. With increasing use of ILM peeling and indocyanine green (ICG) staining, which is used for specific visualization of the ILM, concerns about the safety of the procedure have arisen. At present, it is not known whether ICG-assisted ILM peeling potentially reduces the functional outcome after macular hole surgery. The purpose of the present PhD thesis was to examine whether ICG-assisted ILM peeling offers surgical and functional benefit in macular hole surgery. We conducted a randomized clinical trial including 78 pseudophakic patients with idiopathic macular hole stages 2 and 3. Patients were randomly assigned to macular hole surgery consisting of (i) vitrectomy alone without instrumental retinal surface contact (non-peeling), (ii) vitrectomy plus 0.05% isotonic ICG-assisted ILM peeling or (iii) vitrectomy plus 0.15% trypan blue (TB)-assisted ILM peeling. Morphologic and functional outcomes were assessed 3, 6 and 12 months after surgery. The results show that surgery with ILM peeling, for both stages 2 and 3 macular holes, is associated with a significantly higher closure rate than surgery without ILM peeling (95% versus 45%). The overall functional results confirm that surgery for macular hole generally leads to favourable visual results, with two-thirds of eyes regaining reading vision (>or=20/40). Macular hole surgery can be considered a safe procedure with a low incidence of sight-threatening adverse events; the retinal detachment rate was 2.2%. Visual outcomes in eyes with primary hole closure were not significantly different between the intervention groups; however, for the stage 2 subgroup with primary macular hole closure, there was a trend towards a better mean visual acuity in the non-peeling group (78.2 letters) compared to the ICG-peeling group (70.9 letters), p = 0.06. Performing repeated macular hole surgery was associated with a significant reduction in functional outcome indicating that primary focus should be on closing the macular hole in one procedure. Morphological studies of closed macular holes with contrast-enhanced optical coherence tomography (OCT) found thinning and discontinuity of the central photoreceptor layer matrix that were highly specific for predicting the likelihood of an eye having regained reading vision 12 months after macular hole surgery. Additionally, healing after macular hole surgery appeared to begin with the contraction of the inner aspect of the retina, forming a roof over a subfoveal fluid-filled cavity, and to end with a gradual restoration of the anatomy in the outer layers of the retina at the junction of the photoreceptor inner and outer segments. We found the more intact this structure was on contrast-enhanced OCT 3 months after macular hole surgery, the better the visual acuity after 12 months, whereas late rather than early resolution of subfoveal fluid had no impact on final visual outcome. The use ILM peeling and intraoperative dyes did not have any functionally important effects on postoperative macular structure. Based on the above findings, we conclude that ILM peeling should be performed in all cases of full thickness macular hole surgery. The use of 0.05% intraoperative isotonic ICG with short exposure time appears to be a safe alternative in stage 3 macular hole surgery, whereas a slight reduction in functional potential not can be excluded when performing 0.05% isotonic ICG-assisted ILM peeling in stage 2 macular hole surgery.

Visualizing vitreous in vitrectomy by triamcinolone

BACKGROUND

Visualizing vitreous and retinal surface during vitrectomy, choromovitrectomy, is a novel approach in vitrectomy.

METHODS

Triamcinolone acetonide (TA) is now most commonly used as an adjunct to vitrectomy for this purpose. Intraoperative use of TA can visualize posterior hyaloid, preretinal membrane, internal limiting membrane (ILM) during pars plana vitrectomy, and prolapsed vitreous during cataract surgery, which can make the procedure very safe and effective. TA-assisted vitrectomy is favorably applied to surgery for macular hole, proliferative vitreoretinopathy, diabetic retinopathy, uveitis, and others. In addition, this technique can disclose the residual hyaloid cortex pattern after surgical posterior vitreous detachment. Diffuse posterior hyaloids cortex is frequently seen in diabetic retinopathy and high myopia, and an island-like cortex is often left on the macula, which can be a scaffold of future macular pucker.

RESULTS

The prospective controlled clinical trial showed that TA-assisted vitrectomy reduced the incidence of intraoperative retinal break and retinal detachment more significantly than conventional vitrectomy, although post-operative visual acuity after 1 year was almost the same with each method. Adverse events related to TA-assisted vitrectomy included transient intraocular pressure elevation (approximately 5.0%); most of these events are manageable with topical treatment. The incidence of acute endophthalmitis was 0.03-0.05% , which was at a level comparable to conventional vitrectomy.

CONCLUSIONS

In this article, current status and the possible problems of TA-assisted vitrectomy are reviewed.