Long-term Outcomes of Intraoperative 5-Fluorouracil versus Intraoperative Mitomycin C in Primary Trabeculectomy Surgery

Managing the ocular surface after glaucoma filtration surgery: an orphan topic

BACKGROUND

Ocular surface (OS) disorders before glaucoma filtration surgery (GFS) have been considered to play a crucial role influencing the surgical outcome. Conversely, the impact of surgery itself on the OS is almost completely overlooked, though evidence suggest that ocular surface disease (OSD) may be induced in patients by GFS. This review analyzes the determinants involved in the OSD development after GFS, the clinical features and related consequences, the main diagnostic hallmarks, as well as the therapeutic strategies for its management.

METHODS

The PubMed database was utilized for the literature examination. Keywords that were searched included ocular surface disease, glaucoma filtration surgery, filtration bleb, post-surgical management, and quality of life.

RESULTS

After GFS, OSD is promoted by peri- and post-operative factors, such as the filtration bleb (FB) development, combined surgical approach with phacoemulsification, the use of antifibrotic agents and the reintroduction of antiglaucoma medications. This particular form of OSD that present similar clinical features to mild to moderate dry eye, can be named as post-glaucoma surgery-OSD (PGS-OSD). PGS-OSD may negatively affect the FB functionality, thus potentially hindering the disease control, and significantly worsen the patient quality of life (QOL).

CONCLUSIONS

Clinicians are encouraged to routinely include the OS evaluation after GFS and to consider proper management when the occurrence of PGS-OSD worsen the patient's QOL or exert negative effects to the FB functionality. An outline summarizing the main risk factors and the most appropriate therapeutic options to mitigate the PGS-OSD was proposed to support the routine practice.

Effect of mitomycin C and 5-fluorouracil on wound healing in patients undergoing glaucoma surgery: A meta-analysis

Increased intraocular pressure (IOP) is a risk factor for glaucoma. One treatment option is trabeculectomy. Antimetabolic agents are used in the operation to decrease the post-operative scarring of the wound. The two most common medicines are Mitomycin C (MMC) and 5-Fluorouracil (5-FU). The aim of this research is to assess the effect of MMC on post-operation wound healing in comparison with 5-FU in addition to trabeculectomy. Well, we went through four common databases. Our language was limited to English during the study. The last time we looked at the e-databases was August 2023. Case control studies were performed where MMC resulted in better wound healing than 5-FU. Researchers selected a total of 1023 trials and eventually selected six trials for data analysis. Four hundred and ninety one cases of glaucoma were treated with trabeculectomy. Among them, 246 were given MMC and 245 were given 5-FU during operation. Six trials showed that there was no statistical difference between MMC and 5-FU in the incidence of post-operative wound leak in glaucoma patients who received trabeculectomy (OR, 1.21; 95% CI, 0.63-2.30 p = 0.57); Five trials demonstrated that MMC was associated with a reduced risk of post-operative corneal damage compared to 5-FU injection (OR, 0.18; 95% CI, 0.06-0.56 p = 0.003); In both trials, the incidence of post-operative bleeding was not significantly different from that of 5-FU injected in the MMC group (OR, 0.33; 95% CI, 0.05-2.16 p = 0.25). Our results indicate that MMC is superior to 5-FU in the reduction of post-operative corneal injury. Additional comparisons between MMC and 5-FU are required in order to increase the reliability and effectiveness of these findings.

Treatment Outcomes for Juvenile Open Angle Glaucoma in Thailand

PRCIS

Juvenile open angle glaucoma (JOAG) patients with thick central corneas and negative family history were more likely to undergo surgery, mainly trabeculectomy with half requiring additional surgery within 10 years.

PURPOSE

To assess the characteristics and treatment outcomes of patients with JOAG in Thailand.

PATIENTS AND METHODS

This retrospective, multicenter study included all patients diagnosed with JOAG over 12 years from 2 tertiary hospitals in Bangkok, Thailand.

RESULTS

A total of 200 eyes from 104 patients were included in this study. The mean age of onset was 24.0±10.1 years (range: 5-40 y), with male predominance (60.5%). Over 90% of patients had bilateral JOAG and 25% had a positive family history. Negative family history (adjusted odds ratio=4.59, P =0.02) and thick central corneal thickness were surgical predictors (every 10 µm adjusted odds ratio=1.29, P =0.01). Over 70% of cases needed glaucoma surgery. Trabeculectomy with Mitomycin-C was performed on 131 eyes (65.5%) with a cumulative probability of complete success of 71.0%, 57.8%, 39.2%, and 26.9% and qualified success of 86.3%, 73.6%, 64.8%, and 45.7% at 1, 3, 5, and 10 years, respectively. The mean follow-up after surgery was 94.9 ± 69.8 months (range: 13-153 mo). There were no serious postoperative complications. Myopia and the number of baseline glaucoma medications were significantly associated with surgical failure.

CONCLUSIONS

Trabeculectomy with mitomycin C was the most common primary surgery performed in Thai patients with JOAG, and successfully reduced intraocular pressure without significant complications. Patients with thicker corneas were more likely to undergo surgery. By 10 years, half of the patients required additional surgery and risk factors for failure included myopia and the number of medications.

Multi-Quantitative Assessment of AS-OCTA Complemented AS-OCT for Monitoring Filtering Bleb Function After Trabeculectomy

Purpose

The purpose of this study was to explore a quantitative grading system of the filtering bleb combined anterior segment optical coherence tomography angiography (AS-OCTA) vascular features and optical coherence tomography (OCT) morphological features.

Methods

One hundred three eyes of 103 patients diagnosed with primary open-angle glaucoma and undergone trabeculectomy over 6 months were divided into success and failure groups according to postoperative intraocular pressure (IOP) level. Vessel density (VD) and vessel diameter index (VDI) were examined by AS-OCTA. Bleb's morphology, including bleb height (BH), and microcyst-structure (MCS) were detected by AS-OCT. Multi-vascular model score (MVMS) was calculated by comprehensive factor analysis, and the comprehensive grading system (MVMS-MCS-BH) was analyzed by linear regression. The efficiency our method was verified by receiver operating characteristic (ROC) analysis.

Results

The VD and VDI were higher in the failure group and closely related to post-trabeculectomy IOP (all P = 0.000). The MVMS was mostly consisted of VD in all regions, and VDIs of nasal, central, and temporal positions in sequence. MVMS ≥0, BH <1.33, and non-MCS were significantly associated with IOP increasing (coefficient = -3.23, -3.69, and 8.10, all P = 0.000). MVMS-BH-MCS got a higher area under curve (AUC), sensitivity, and specificity (0.92, 100%, and 80.30%) than the slit-lamp method (0.62, 72.20%, and 46.43%, respectively).

Conclusions

The quantitative vascular characteristics detected by AS-OCTA were significant for the bleb monitor. The MVMS-BH-MCS grading system had achieved outstanding accuracy in reflecting the surgical results.

Translational Relevance

The multi-vascular biomarker and comprehensive evaluation combined vascular and morphological parameters yield useful information on surgical outcomes, and help ophthalmologists to monitor patients effectively.

Mitomycin C-loaded PTMC15-F127-PTMC15 hydrogel maintained better bleb function after filtering glaucoma surgery in monkeys with intraocular hypertension

There is an unmet need for a safer and more effective approach for antimetabolite application to prevent bleb fibrosis after glaucoma filtering surgery. Here, we utilized our previously developed thermosensitive sustained-release agent, mitomycin C-loaded poly(trimethylene carbonate)15-F127-poly(trimethylene carbonate)15 (MMC-hydrogel), aiming to further evaluate the efficacy and safety of MMC-hydrogel in high intraocular pressure (IOP) primate eyes. Twelve primate eyes after high IOP induction were randomly divided into three groups, which respectively received phosphate-buffered saline (PBS)-hydrogel, MMC-hydrogel, and MMC treatment during trabeculectomy. IOP and bleb volume were measured using a Tonopen and anterior segment optical coherence tomography over 28 days. At the end of the experiment, all experimental primate eyes were enucleated. Histopathology and immunohistochemistry were performed to reveal myofibroblast cells and collagen deposition of filtering blebs. The MMC-hydrogel group had satisfactory IOP control (9.25 ± 4.80 mmHg) and maintained well-functioning blebs for a longer time. Fibrosis and scarring were significantly alleviated in this MMC-hydrogel group. There was no obvious toxicity to ocular surfaces or intraocular structures. Taken together, these data suggest that PTMC15-F127-PTMC15-loaded MMC-hydrogel plays a role in functional maintenance and scarring inhibition, showing high efficacy in reducing post-filtering surgery bleb fibrosis. This MMC-hydrogel may offer a new solution for filtering bleb management after glaucoma surgery.

Comparison of tube shunt implantation and trabeculectomy for glaucoma: a systematic review and meta-analysis

OBJECTIVE

To compare the efficacy and safety of tube shunt implantation with trabeculectomy in the treatment of patients with glaucoma.

METHODS

A systematic literature search was performed for studies comparing tube with trabeculectomy in patients with glaucoma (final search date: 27 February 2022). Comparisons between tube and trabeculectomy were grouped by the type of tube (Ahmed, Baerveldt, Ex-PRESS and XEN). The primary endpoints included intraocular pressure (IOP), IOP reduction (IOPR), IOPR percentage (IOPR%), complete success rate (CSR), qualified success rate (QSR) and adverse events (AEs).

RESULTS

Forty-nine studies were included in this meta-analysis and presented data for 3795 eyes (Ahmed: 670, Baerveldt: 561, Ex-PRESS: 473, XEN: 199, trabeculectomy: 1892). Ahmed and Ex-PRESS were similar to trabeculectomy in terms of IOP outcomes and success rate (Ahmed vs trabeculectomy: IOPR%: mean difference (MD)=1.34 (-5.35, 8.02), p=0.69; Ex-PRESS vs trabeculectomy: IOPR%: MD=0.12 (-3.07, 3.31), p=0.94). The IOP outcomes for Baerveldt were worse than those for trabeculectomy (IOPR%: MD=-7.51 (-10.68, -4.35), p<0.00001), but the QSR was higher. No significant difference was shown for the CSR. XEN was worse than trabeculectomy in terms of IOP outcomes (IOPR%: MD=-7.87 (-13.55, -2.18), p=0.007), while the success rate was similar. Ahmed and Ex-PRESS had a lower incidence of AEs than trabeculectomy. Baerveldt had a lower incidence of bleb leakage/wound leakage, hyphaema and hypotonic maculopathy than trabeculectomy but a higher incidence of concurrent cataracts, diplopia/strabismus and tube erosion. The incidence of AEs was similar for the XEN and trabeculectomy procedures.

CONCLUSION

Compared with trabeculectomy, both Ahmed and Ex-PRESS appear to be associated with similar ocular hypotensive effects and lower incidences of AEs. However, Baerveldt and XEN cannot achieve sufficient reductions in IOP outcomes similar to those of trabeculectomy.

PROSPERO REGISTRATION NUMBER

CRD42021257852.

Differences in the Surgical Outcomes of Glaucoma Surgery in Patients of African Caribbean Descent

PURPOSE

People of African Caribbean Descent (ACD) have a higher prevalence of glaucoma compared to people of European Descent (ED) and there is uncertainty if treatment outcomes are equivalent between the two groups. To assess surgical failure rates comparing ACD with ED focusing on trabeculectomy, aqueous shunt implantation, non-penetrating filtering surgery (NPFS), and minimally invasive glaucoma surgery (MIGS) by performing a systematic review in accordance with the PRISMA guidelines and to determine whether there is any evidence in to show a difference in success rates based on race.

METHODS

A systematic review of articles using the CENTRAL, Ovid MEDLINE, PubMed, EMBASE, and ClinicalTrials.gov databases was completed. Additional studies were identified by contacting clinical experts and searching bibliographies. All retrospective and prospective studies on trabeculectomy, aqueous shunt implantation, NPFS, and MIGS that included at least 20% ACD were included. Two review authors independently screened search results for eligibility and inclusion and extracted the data using pre-determined fields.

RESULTS

A total of 76 studies were identified for inclusion in the review. Glaucoma surgical outcomes in ACD appear to be poorer compared to ED overall, particularly for trabeculectomy. Data on NPFS are limited, but the studies completed thus far demonstrate surprisingly good results for ACD, particularly when compared to ED, who have significantly lower pre-operative IOPs. Evidence from studies investigating aqueous shunts does not suggest that ACD have poorer outcomes than ED. There is not enough data on MIGS to provide a significant conclusion.

CONCLUSION

In a population where trabeculectomy may no longer be the gold standard, sufficiently powered studies assessing surgical outcomes in aqueous shunts, NPFS, and MIGS are needed to guide clinicians.

High-Frequency Deep Sclerotomy as Adjunctive Therapy in Open-Angle Glaucoma Patients

INTRODUCTION

Glaucoma is a chronic, progressive disease of the optic nerve that can cause vision loss and blindness. High-frequency deep sclerotomy (HFDS) is a novel ab interno procedure used to lower intraocular pressure (IOP). This study aims at examining hypotensive effects of HFDS in patients with medically uncontrolled primary open-angle glaucoma (POAG).

METHODS

23 patients (23 eyes) participated in this study. They were all affected by POAG and used maximum prescribed medical therapy. It is important to note that the target IOP was not detected in any study participant. The target IOP is the highest IOP value at which no new damages of the optic nerve occur. The procedure was performed with a custom-made, high-frequency dissection probe by applying bipolar current of 500 kHz. Six pockets (1 mm deep, 0.3 mm high, and 6 mm wide) were made ab interno in nasal sclera (through trabecular meshwork and Schlemm's canal). Tobramycin/dexamethasone and pilocarpine eye drops were administered postoperatively for a month.

RESULTS

The mean value of the base IOP had been 25.6 mm Hg before the procedure. Significant complications were not recorded either during the surgery or in a postoperative follow-up period. The average IOP for our patients reduced by 8.6 mm Hg (33.6%) after a year. The mean value of the instilled anti-glaucoma eye drops had been 2.78 (SD = 0.45) before the HFDS and 0.61 (SD = 1.04) at the end of the research. The target IOP was not achieved in five cases (21.7% of our sample).

DISCUSSION/CONCLUSION

This study presents the data on our first surgical experience with HFDS that was conducted on 23 patients who had medically uncontrolled POAG. The results indicate that HFDS is safe and efficient in reducing IOP.

Subconjunctival Lymphatics Respond to VEGFC and Anti-Metabolites in Rabbit and Mouse Eyes

Purpose

To characterize and pharmacologically influence subconjunctival lymphatics in rabbit and mouse eyes.

Methods

Rabbits received subconjunctival injections of trypan blue or fixable fluorescent dextrans. Bleb-related outflow pathways were quantified. Immunofluorescence for vessel-specific markers (lymphatics [podoplanin and LYVE-1] and blood vessels [CD31]) were performed in native rabbit conjunctiva and after fixable fluorescent dextran injection. Vascular endothelial cell growth factor-C (VEGFC) was injected subconjunctivally in rabbits. mRNA and protein were assessed for the above markers using RT-PCR and Western blot. Alternatively, mouse studies used Prox1-tdTomato transgenic reporter mice. Subconjunctival injection conditions included: no injection, balanced salt solution (BSS), VEGFC, 5-fluorouracil (5FU) and two concentrations of mitomycin-C (MMC). Two mouse injection protocols (short and long) with different follow-up times and number of injections were performed. Mouse eyes were enucleated, flat mounts created, and subconjunctival branching and length assessed.

Results

Rabbit eyes demonstrated clear bleb-related subconjunctival outflow pathways that were distinct from blood vessels and were without nasal/temporal predilection. Immunofluorescence against vessel-specific markers showed lymphatics and blood vessels in rabbit conjunctiva, and these lymphatics overlapped with bleb-related subconjunctival outflow pathways. Subconjunctival VEGFC increased lymphatic (P = 0.004-0.04) but not blood vessel (P = 0.77-0.84) mRNA or protein in rabbits. Prox1-tdTomato transgenic reporter mice demonstrated natively fluorescent lymphatics. Subconjunctival VEGFC increased murine lymphatic branching and length (P ≤ 0.001-0.004) while antimetabolites (P ≤ 0.001-0.043) did the opposite for the long protocol.

Discussion

Subconjunctival lymphatics are pharmacologically responsive to both VEGFC and antimetabolites in two animal models studied using different methodologies. These results may be important for bleb-forming glaucoma surgeries or ocular drug delivery.

The Efficacy of Atelocollagen to Inhibit Fibrotic Proliferation in Tenon Tissue: In vitro Study

INTRODUCTION

The aim of the study was to evaluate the safety and efficacy of atelocollagen in preventing the fibrotic change of human tenon tissue induced by transforming growth factor β1 (TGFβ1).

METHODS

Primary cultured human Tenon's fibroblasts (HTFs) were incubated with TGFβ1 alone and with various concentrations of atelocollagen, respectively. Cell viability was measured by Cell Counting Kit-8 (CCK-8). The mRNA levels of α-smooth muscle actin (α-SMA), vimentin, fibronectin, zonular occludens scaffolding protein (ZO-1), cellular communication network factor 2 (CCN2), and interleukin 6 (IL-6) were measured by quantitative reverse transcription polymerase chain reaction, Western blot, and immunofluorescence analysis. Wound healing assay and collagen contraction assay were additionally evaluated for identifying the inhibitory effect of atelocollagen in HTFs. To elucidate the mechanism by which atelocollagen affects HTF proliferation, the phospho-extracellular-signal-regulated kinases (pERK)/total-extracellular-signal-regulated kinases (tERK), phospho-focal adhesion kinase (pFAK)/total-focal adhesion kinase (tFAK), and pSmad3/tSmad3 protein expression ratios were measured by Western blot.

RESULTS

The safety of atelocollagen in HTF was identified by CCK-8 analysis. The expression of α-SMA and vimentin in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased at both mRNA and protein levels, while that of ZO-1 in 0.046% atelocollagen increased compared with TGFβ1-treated cells. The protein expression of fibronectin, CCN2, and IL-6 in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased. The immunofluorescence microscopy of α-SMA and ZO-1 showed results similar to those of the Western blot. In the wound-scratch assays, cell migration was significantly attenuated in HTFs treated with 0.005% atelocollagen. Atelocollagen at 0.005, 0.011, and 0.023% significantly inhibited the gel contraction induced by TGFβ1 at both 24 h and 48 h. The increase in pERK/tERK and pSmad3/tSmad3 protein expression ratios in TGFβ1-treated HTFs significantly decreased after treatment with 0.023 and 0.046% atelocollagen.

CONCLUSION

Since atelocollagen gel effectively suppresses the proliferation of HTFs in TGFβ1-induced transdifferentiation, it may be a potential therapeutic agent in glaucoma surgery.

Reintervention rate in glaucoma filtering surgery: A systematic review and meta-analysis

PURPOSE

Reintervention rate is an important factor impacting on patients, surgeons, and society. To date, only a few studies have focused on this topic. For this reason, a systematic review and meta-analysis was undertaken to assess the reintervention rate after glaucoma filtering surgery.

MATERIALS AND METHODS

Prospective studies reporting the reintervention rate after glaucoma filtering surgery and with at least 12 months of follow-up were systematically searched on PubMed, Medline and Embase databases. The primary outcome was the total reintervention rate following surgery. Secondary outcomes were: the rate of manipulation, in-clinic and in-operating room reintervention; the reintervention rate for intraocular pressure (IOP) control and for complications; demographic, clinical and surgical variables associated with reintervention rate.

RESULTS

Ninety-three studies with a total of 8345 eyes were eligible. The total reintervention rate was 1.84 (95% CI 1.57-2.13), with a lower rate for Baerveldt (0.53, 95% CI 0.29-0.83) and Preserflo (0.60, 95% CI 0.15-1.29), and a higher rate for Xen (4.26, 95% CI 2.59-6.31). The manipulation rate was 0.99 (95% CI 0.77-1.23), the in-clinic reintervention rate was 0.08 (95% CI 0.05-0.12) and the in-operating room reintervention rate was 0.28 (95% CI 0.22-0.35). The reintervention rate for IOP control was 1.26 (95% CI 1.04-1.51) and the reintervention rate for complications was 0.27 (95% CI 0.21-0.35).

CONCLUSIONS

All types of surgery presented a total reintervention rate similar to the overall findings, except studies on Baerveldt and Preserflo Microshunt, with a lower rate, and Xen, with a higher rate. None of the variables evaluated were found to be directly associated with the explored outcomes.

Characteristic Assessment of Angiographies at Different Depths with AS-OCTA: Implication for Functions of Post-Trabeculectomy Filtering Bleb

This study aimed to analyze the quantitative vascular biomarkers of filtering bleb function at different depths using anterior segment optical coherence tomography angiography (AS-OCTA). This cross-sectional study is registered on Clinicaltrails.gov (NCT 04515017). Forty-six eyes with primary open-angle glaucoma that had undergone trabeculectomy with mitomycin-C for more than six months were included. Vessel density (VD) and vessel diameter index (VDI) in the superficial layer (SL), Tenon’s layer (TL), and deep layer (DL) of the bleb were obtained. The VD and VDI were higher in the failure group (both p = 0.000). Significant correlations were found between the SL, TL, DL’s VDI, and IOP in the success group (p = 0.013, 0.016, 0.031, respectively). The VD of the TL and DL were related to IOP in the failure group (p = 0.012, 0.009). Tenon’s VD (TVD) and Tenon’s VDI (TVDI) correlated with IOP adjusting for TVD, TVDI, and the Indiana Bleb Appearance Grading Scale (IBAGS) (p = 0.009, 0.043) or Kenfeld grading system (KGS) (p = 0.011, 0.016). The area under curve (AUC) of the TVD, TVDI, IBAGS, and KGS to predict surgery failure were 0.960, 0.925, 0.770, and 0.850. AS-OCTA realized the quantitative evaluation of vessels, especially the invisible vascularity beneath the conjunctiva. TVD and TVDI as detected by AS-OCTA better reflected bleb function than conventional grading systems.

[Pharmacological modulation of wound healing in glaucoma surgery]

Despite the well-known effectiveness of pharmacological glaucoma therapy, surgical approach remains one of the main treatment options for some forms and stages of the disease. The long-term success of glaucoma surgery depends on the intensity of local wound healing processes at the surgical site. The most common way to influence healing processes in surgical treatment of glaucoma is the use of antimetabolites. However, given the high risk of serious complications associated with their use, the search for new drugs devoid of these disadvantages continues. The aim of this review is to describe the efficacy and safety of both currently used and upcoming pharmacological ways to influence the wound healing process after glaucoma surgery in order to improve the stability of hypotensive effect.

Evaluation of Topical Mitomycin-C Eye Drops After Reconstructive Surgery for Anophthalmic Contracted Socket

Purpose

To report the outcomes of using topical mitomycin-C (MMC) after reconstructive surgery for contracted socket and to compare the results with those of the conventional postoperative treatment.

Patients and Methods

The medical records of patients who underwent reconstructive surgery for contracted anophthalmic socket were retrospectively reviewed. Based on the postoperative treatment protocol, two groups of patients were identified; group I (15 patients) who received topical MMC drops (0.02%) 4 times daily for 6 weeks and group II (15 patients) who received the conventional treatment (topical antibiotic-steroid combination). Preoperative data were extracted for age, gender, cause and timing of anophthalmia, history of previous surgeries, preoperative forniceal depth and socket volume (SV). The main postoperative outcome measures were superior fornix depth (SFD), inferior fornix depth (IFD) and SV at the end of 6th postoperative month. Prosthesis fitting and complications were also considered for analysis.

Results

The mean preoperative IFD was 1.67±0.04 mm in group I and 1.58±0.37 mm in group II, by the end of the 6th postoperative month it increased to 6.1 ±0.27 mm and 5.12 ±0.25mm, respectively. The mean preoperative SFD in group I was 8.3±0.9 mm and 8.9±1.1 mm in group II, by the end of the 6th postoperative month SFD became 13.4±1.2 mm and 10.2±1.4 mm in groups I and II, respectively. The mean SV measured six months postoperatively was 1.9±0.2 mL and 1.3±0.09 mL in groups I and II, respectively. These differences in the postoperative SFD, IFD and SV between both groups were statistically significant. More cases reported successful fitting in group I than in group II but this difference was not statistically significant.

Conclusion

Postoperative use of topical MMC is associated with higher forniceal depth and greater SV when compared to the conventional treatment in socket reconstructive surgeries with amniotic membrane graft (AMG).

Mechanisms of reducing joint stiffness by blocking collagen fibrillogenesis in a rabbit model of posttraumatic arthrofibrosis

Posttraumatic fibrotic scarring is a significant medical problem that alters the proper functioning of injured tissues. Current methods to reduce posttraumatic fibrosis rely on anti-inflammatory and anti-proliferative agents with broad intracellular targets. As a result, their use is not fully effective and may cause unwanted side effects. Our group previously demonstrated that extracellular collagen fibrillogenesis is a valid and specific target to reduce collagen-rich scar buildup. Our previous studies showed that a rationally designed antibody that binds the C-terminal telopeptide of the α2(I) chain involved in the aggregation of collagen molecules limits fibril assembly in vitro and reduces scar formation in vivo. Here, we have utilized a clinically relevant arthrofibrosis model to study the broad mechanisms of the anti-scarring activity of this antibody. Moreover, we analyzed the effects of targeting collagen fibril formation on the quality of healed joint tissues, including the posterior capsule, patellar tendon, and subchondral bone. Our results show that blocking collagen fibrillogenesis not only reduces collagen content in the scar, but also accelerates the remodeling of healing tissues and changes the collagen fibrils’ cross-linking. In total, this study demonstrated that targeting collagen fibrillogenesis to limit arthrofibrosis affects neither the quality of healing of the joint tissues nor disturbs vital tissues and organs.

Combined Trabeculotomy-Trabeculectomy Versus Trabeculectomy for Treatment of Silicone Oil-induced Ocular Hypertension

PRCIS

Combined trabeculotomy-trabeculectomy (CTT) has a significantly better hypotensive effect than trabeculectomy and a higher success rate in cases of silicone oil-induced ocular hypertension.

PURPOSE

To compare the ocular hypotensive effect of CTT with mitomycin-C (MMC) to that of trabeculectomy with MMC in cases of silicone oil-induced ocular hypertension.

PATIENTS AND METHODS

Thirty eyes of 30 patients with high intraocular pressure (IOP) after vitrectomy and silicone oil injection (followed by silicone oil removal) were randomly allocated to 2 groups in this randomized trial. Group A was composed of 15 cases who underwent combined CTT with MMC while group B cases contained 15 cases undergoing trabeculectomy with MMC. Patients were followed up for 12 months. We included patients above 18 years old, having performed vitrectomy and silicone oil injection followed by oil removal, and having IOP >21 mm Hg uncontrollable by antiglaucoma medications.

RESULTS

The postoperative IOP drop was significantly greater in group A than in group B at all follow up visits (P<0.05). Compared with preoperative IOP, both surgeries produced a significantly lower postoperative IOP at all follow-up visits (P<0.05). For group A, complete success rates (IOP≤21 mm Hg without ocular hypotensive medications) and qualified success rates (IOP≤21 mm Hg with or without ocular hypotensive medications) were both higher than for group B.

CONCLUSION

Both surgeries effectively reduce IOP in cases of silicone oil-induced ocular hypertension, but CTT has a significantly better hypotensive effect and a higher success rate on the long-term.

Trabeculectomy with OloGen versus Mitomycin C for the Treatment of Silicone Oil-Induced Glaucoma

AIM

To compare the intraocular pressure-lowering effect and success rate of trabeculectomy with OloGen to that of trabeculectomy with mitomycin C (MMC) in cases of silicone oil-induced glaucoma.

MATERIALS AND METHODS

Forty eyes of forty patients with elevated intraocular pressure (IOP) after vitrectomy and silicone oil injection (followed by silicone oil removal) were assigned to two groups. Group A included 20 cases who underwent trabeculectomy with OloGen, while group B cases contained 20 cases undergoing trabeculectomy with MMC. The follow-up period was 24 months. Patients enrolled had IOP > 21 mmHg despite being on antiglaucoma medications.

RESULTS

The mean postoperative IOP reduction was lower in group A than in group B at all follow-up visits, but this difference was not statistically significant (p > 0.05). Moreover, group A and B patients were found to be similar as regards the need for postoperative antiglaucoma medications on all follow-up visits. The Kaplan-Meier survival analysis curves for the two groups revealed slightly higher success rates in group B than in group A. However, these differences were not statistically significant for both qualified success (IOP ≤ 21 mmHg with or without antiglaucoma medications) and complete success (IOP ≤ 21 mmHg without antiglaucoma medications). There was no significant difference in the postoperative complication rate between the two groups.

CONCLUSION

OloGen implant lowers IOP to a similar extent as MMC when combined with trabeculectomy for the treatment of silicone oil-induced glaucoma, and with comparable success rates. The rate of postoperative complications is similar for OloGen implantation and MMC.

Deep sclerectomy and trabeculectomy augmented with Mitomycin C: 2-year post-operative outcomes

Purpose

Two-year post-operative outcomes of both deep sclerectomy (DS) and trabeculectomy surgery (Trab) augmented with Mitomycin C (MMC) at a single tertiary eye centre.

Methods

Retrospective review of DS + MMC and trabeculectomy + MMC at a single centre between February 2015 and March 2018. Patients with a minimum of 12-month follow-up were included. Post-operative follow-up: day 1, week 1, months 1/3/6/12/18/24. Primary outcomes: changes in intraocular pressure (IOP) and changes in LogMAR visual acuity (BCVA) pre- and post-procedure. Secondary outcomes: changes in number of eye drops, number of follow-up clinic visits, post-operative complications and further surgical interventions. Complete success: IOP ≤ 21 mmHg off all IOP-lowering medications. Qualified success: IOP ≤ 21 mmHg on medication. Failure: IOP > 21 mmHg at 24 months or ≤ 5 mmHg on 2 consecutive follow-up visits after 3 months +/− additional incisional glaucoma surgery +/− loss of light perception. Statistical analysis performed using Microsoft Excel + SPSS.

Results

90 eyes: DS + MMC = 46 eyes, Trab + MMC = 44 eyes. DS + MMC v Trab + MMC: mean pre-op IOP = 19.57 mmHg v 18.89 mmHg, significantly reduced at all post-operative time-points for both groups (p < 0.001). Mean IOP reduction from baseline = 33.94% v 38.39%; > 30% IOP reduction = 54.35% v 68.18%. IOP ≤ 16 mmHg = 82.61% (38/46) v 95.46% (42/44), IOP ≤ 12 mmHg = 52.17% (24/46) v 72.72% (32/44). Complete success = 67.39% v 61.36%, qualified success = 26.09% v 29.55%, failure = 6.52% v 9.09%. Post-op BCVA: no statistically significant differences between two groups (p = 0.09). Mean pre-op drops v post-op drops = 2.98 v 0.38 (DS + MMC; p < 0.001); 2.68 v 0.39 (Trab + MMC; p < 0.001). Further surgical intervention = 13% v 29.55%. Mean number of post-op clinic visits DS + MMC v Trab + MMC = 10.09 v 13.02 (p = 0.005).

Conclusion

Both procedures achieve sustained intraocular pressure and drop reduction at 2 years post-op. DS + MMC has lower complication rates requiring less intervention and significantly fewer clinic visits, which may be an important factor for deciding surgical management of glaucoma patients in the era of Covid-19 to reduce patient/clinician exposure to the virus.

Common and rare complications following filtering surgery for children with congenital glaucoma; a5 years study

PURPOSE

To determine the incidence of postoperative complications following combined trabeculotomy trabeculectomy with mitomycin C (CTTM) for congenital glaucoma (CG), in addition to documentation of some unusual complications and possible ways to manage these complications safely with minimal morbidity.

METHODS

A retrospective observational study was performed on 190 eyes with CG had a CTTM procedure.Included eyes were operated upon between February 2015 and February 2020 in Sohag University Hospitals. Medical records were reviewed and postoperative complications were reported. Incidence of postoperative complications and their management were the main outcome measures.

RESULTS

Early complications developed the form of shallow anterior chamber (AC) (16.3%), hyphema (10.5%), serous choroidal detachment (2%), hemorrhagic choroidal detachment (2%). Unusual and rare complications occurred in the form of iatrogenic Cushing syndrome, unilateral toxic keratopathy developed, vitreous hemorrhage (VH), intercalary staphyloma and decompression retinopathyLate complications included: high postoperative intraocular pressure (IOP) (16.5%), thin cystic blebs (13.1%), hypotony disc edema (2%), cataract (3.2%), one eye developed blebitis and one eye developed endophthalmitis.

CONCLUSION

Surgical management of CG is full of complications in early and late postoperative periods such as shallow AC, hyphema and thin cystic blebs. Some unusual and rare complications developed such as iatrogenic Cushing syndrome, unilateral toxic keratopathy, vitreous hemorrhage, intercalary staphyloma and decompression retinopathy. If identified early; all these complications could be managed properly leading to a successful and favorable outcome.

Novel combination therapy reduces subconjunctival fibrosis after glaucoma filtration surgery in the rabbit model

BACKGROUND

Glaucoma filtration surgery (GFS) is limited by subconjunctival, episcleral and scleral fibrosis sealing the trabeculectomy and scarring the filtering bleb. Mitomycin-C (MMC) is commonly applied intraoperatively to the subconjunctival and/or intrascleral space to reduce scarring and promotes GFS success but is associated with postoperative scleral melting and bleb leaks. IP-10 peptide (IP-10p), an ELR-negative CXC chemokine mimetic and inhibitor of fibroblast function, may be an alternative or adjunct to current postoperative GFS treatments. This study sought to determine if IP-10p produces histological changes in tissue remodelling, vascularity and fibrosis that enhance bleb survival after GFS.

METHODS

Rabbits underwent tube-assisted filtration surgery on the right eye with either: (a) IP-10p injected into bleb at time of surgery and postoperative days 2, 4 and 7, (b) intraoperative MMC or (c) intraoperative MMC plus IP-10p injected into bleb at time of surgery and postoperative days 2, 4 and 7. Left contralateral eyes were treated with balanced salt solution (BSS).

RESULTS

IP-10p-treated blebs demonstrated reduced collagen deposition, cellularity and overall reduction of scar formation compared to BSS-control. Bleb vascularity was reduced compared to BSS-control and MMC treatment groups. Additionally, IP-10p/MMC treated eyes demonstrated an increased number of conjunctival goblet cells in bleb histology compared to the dramatic loss seen with MMC treatment alone.

CONCLUSIONS

This study demonstrates that IP-10p significantly reduces histological scarring compared to BSS or MMC alone, does not damage the conjunctiva to the extent of current standards, and may be an alternative or adjunct to MMC for those undergoing GFS.

Pluripotent epigenetic regulator OBP-801 maintains filtering blebs in glaucoma filtration surgery model

Inhibition of fibrosis is indispensable for maintaining filtering blebs after glaucoma filtration surgery (GFS). The purpose of this study was to investigate the ability of a pluripotent epigenetic regulator OBP-801 (OBP) to ameliorate extracellular matrix formation in a rabbit model of GFS. Rabbits that underwent GFS were treated with OBP. The gene expression profiles and intraocular pressure (IOP) were monitored until 30 postoperative days. The bleb tissues were evaluated for tissue fibrosis at 30 postoperative days. In in vitro models, OBP interfered the functions of diverse genes during the wound-healing process. In in vivo GFS models, the expressions of TGF-β3, MMP-2, TIMP-2 and 3, LOX, COL1A and SERPINH1 were significantly inhibited at 30 postoperative days in the OBP group compared with those in the vehicle control group. OBP treatment involving subconjunctival injection or eye drops showed no adverse effects, and reduced levels of α-SMA and collagen deposition at the surgical wound site. OBP maintained the long-lived bleb without scar formation, and IOP was lower at 30 postoperative days compared with the vehicle control group. These findings suggest that OBP is an effective and useful candidate low-molecular-weight agent for improving wound healing and surgical outcomes in a rabbit model of GFS.

Results of fluorouracil-augmented Xen45 implantation in primary open-angle and pseudoexfoliation glaucoma

PURPOSE

To report the effectiveness and safety of 5-fluorouracil (5-FU)-augmented Xen45 implantation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PEXG).

METHODS

This single-center, retrospective chart review study included 29 eyes that underwent 5-FU-augmented Xen45 implantation. Main outcome measures were intraocular pressure (IOP) levels and number of glaucoma medications. Surgical success was defined as IOP ≤ 21 mmHg and ≥ 20% reduction from preoperative levels without (complete success) or with (qualified success) glaucoma medications and without further glaucoma surgery at last follow-up. All postoperative interventions and complications were also noted.

RESULTS

The mean age of the patients was 67.5 ± 10.3 years, and the mean follow-up time was 23.2 ± 12.6 months. Mean IOP was 24.5 ± 8.7 mmHg and decreased by 30.2% at 12 months, 24.9% at 24 months, and 31.7% at final visit (p < 0.001, p = 0.006, p > 0.001, respectively). Mean number of glaucoma medications decreased from 2.83 preoperatively to 0.71 at 12 months, 0.87 at 24 months, and 0.86 at final visit (p < 0.001). At final visit, the complete success rate was 48.3%, qualified success rate was 69%, and 62.1% of the eyes were free of glaucoma medications. Needling was performed in 7 eyes (24%). Adverse events included choroidal detachment in 5 eyes, hyphema in 2 eyes, and endophthalmitis in 1 eye.

CONCLUSION

5-FU-augmented Xen45 implantation in POAG and PEXG patients provided safe and effective IOP lowering with significant reduction of glaucoma medications up to 3 years.

Does adjuvant intracameral triamcinolone acetonide increase the effectiveness of phacotrabeculectomy? A Case-Control Study

AIMS

To investigate the effect of intracameral triamcinolone acetonide (TA) on surgical success in 5-fluorouracil (5-FU) supported primary phacotrabeculectomy (PT) cases.

MATERIAL AND METHODS

This retrospective study included 23 eyes (study group) of 23 patients who underwent TA during PT and 26 eyes (control group) of 26 patients without TA. PT patients in the study group received 1 mg TA intraoperatively at the end of surgery. Pre- and postoperative visual acuity, intraocular pressure (IOP), and number of antiglaucoma drugs used were compared. Postoperative complications and need for 5-FU injection were evaluated for both groups.

RESULTS

Mean age was 64.1 2 ± 1.91 (48-86) years in the control group and 66.52 ± 2.02 (52-86) years in the study group (p = 0.824). Comparison of pre- and postoperative IOP values showed significant decreases in postoperative IOP levels at all-time points in both the control and study groups (p &lt; 0.001). The only significant difference between groups was on postoperative first day (study group: 9.22 ± 1.41 mmHg; control group: 6.35 ± 2.17 mmHg, p &lt; 0.001). Need for postoperative 5-FU injection was significantly more common in the control group (p = 0.023).

CONCLUSION

Intracameral injection of 1 mg TA at the end of PT surgery did not yield superior results in postoperative IOP compared to PT alone, and the two groups showed similar IOP reduction. When given as an adjunct to PT, 1 mg TA suppresses anterior segment inflammation and reduces the need for 5-FU injection.

Minimally Invasive Surgery in Mild-to-Moderate Glaucoma Patients in Italy: Is It Time to Change?

Medical therapy is the first treatment choice for most patients with glaucoma; however, in a relevant proportion of patients, intraocular pressure (IOP) reduction is achieved with multi-therapy and/or high therapeutic doses. Conventional surgery is the standard alternative to medical therapy when this is not effective or not tolerated. Recently, selective laser trabeculoplasty (SLT) has been advocated as first-line therapy, and "minimally invasive glaucoma surgery" (MIGS) has been developed as safer and less traumatic surgical intervention for patients with glaucoma. Schlemm's canal surgery has emerged as one of the approaches with the most favorable risk-benefit profile for glaucoma patients in need of cataract surgery. However, despite the promising results, use of MIGS in Italy has been extremely low. We aimed to investigate the reasons of the lower-than-expected use of Schlemm's canal-based MIGS devices in Italy, share our perspective on their potential place in therapy, and give practical suggestions to improve the management of glaucoma patients.

Improving Visual Field Trend Analysis with OCT and Deeply Regularized Latent-Space Linear Regression

PURPOSE

To investigate whether OCT measurements can improve visual field (VF) trend analyses in glaucoma patients using the deeply regularized latent-space linear regression (DLLR) model.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Training and testing datasets included 7984 VF results from 998 eyes of 592 patients and 1184 VF results from 148 eyes of 84 patients with open-angle glaucoma, respectively. Each eye underwent a series of 8 VF tests with the Humphrey Field Analyzer OCT series obtained within the same observation period.

METHODS

Using pointwise linear regression (PLR), the threshold values of a patient's eighth VF results were predicted using values from shorter VF series (first to second VF tests [VF1-2], first to third VF tests, . . . , to first to seventh VF tests [VF1-7]), and the root mean square error (RMSE) was calculated. With DLLR, OCT measurements (macular retinal nerve fiber layer thickness, the thickness of macular ganglion cell layer and inner plexiform layer, and the thickness of the outer segment and retinal pigment epithelium) that were obtained within the period of shorter VF series were incorporated into the model to predict the eighth VF.

MAIN OUTCOME MEASURES

Prediction accuracy of VF trend analyses.

RESULTS

The mean ± standard deviation RMSE resulting from PLR averaged 27.48 ± 16.14 dB for VF1-2 and 3.98 ± 2.25 dB for VF1-7. Significantly (P < 0.001) smaller RMSEs were obtained from DLLR: 4.57 ± 2.71 dB (VF1-2) and 3.65 ± 2.27 dB (VF1-7).

CONCLUSIONS

It is useful to include OCT measurements when predicting future VF progression in glaucoma patients, especially with short VF series.

Differential Effects of TGF-β2 on the Low-Density Lipoprotein Receptor Expression in Three Types of Human Subconjunctival Fibroblasts

Purpose: To investigate whether TGF-β2 had a different effect on the expression levels of low-density lipoprotein receptor (LDLr) in the subconjunctival fibroblasts from glaucoma patients who underwent a reoperation (RGSFs) compared with those from glaucoma patients who underwent first filtering surgery (GSFs) and control patients with cataracts (HSFs). Methods: Human subconjunctival fibroblasts were obtained from the three groups of patients. Different concentrations of TGF-β2 were added to the fibroblasts for 1, 3, and 5 days. The proliferation of the fibroblasts was determined by CCK-8 assays. Real-time PCR and western blotting were performed to analyze the mRNA and protein levels of LDLr. The uptake of DiI-labeled LDL was determined by confocal microscopy. Results: The results revealed that under TGF-β2 exposure, fibroblast proliferation was positively correlated with LDLr expression (all p < .001). The LDLr mRNA and protein levels were affected by TGF-β2 in a concentration-dependent and time-dependent manner in the RGSFs, GSFs and HSFs. The maximal expression of LDLr after TGF-β2 stimulation was consistent with the peak uptake of DiI-LDL, which was obviously highest in the RGSFs, followed by the GSFs, and then the HSFs (all p < .05). All 3 groups took up DiI-LDL in a similar time-dependent manner, with maximal uptake at 6 h following DiI-LDL incubation (all p < .05). In addition, there were significant differences in the LDLr protein levels in the subconjunctival tissues isolated from the glaucoma patients during reoperation, the glaucoma patients during first filtering surgery and the control patients at day 3 (p < .05). The highest protein expression of LDLr was observed in the RG group. Conclusion: These data suggested that the RGSFs had the highest LDLr expression and the highest peak uptake of LDL among three groups. The LDLr-drug-LDL delivery system could potentially be used for targeted delivery of antimetabolite agents in anti-scarring therapy for glaucoma patients after filtering surgery.

Functional, structural, and molecular identification of lymphatic outflow from subconjunctival blebs

The purpose of this study is to evaluate outflow pathways from subconjunctival blebs and to identify their identity. Post-mortem porcine (n = 20), human (n = 1), and bovine (n = 1) eyes were acquired, and tracers (fluorescein, indocyanine green, or fixable/fluorescent dextrans) were injected into the subconjunctival space to create raised blebs where outflow pathways were visualized qualitatively and quantitatively. Rodents with fluorescent reporter transgenes were imaged for structural comparison. Concurrent optical coherence tomography (OCT) was obtained to study the structural nature of these pathways. Using fixable/fluorescent dextrans, tracers were trapped to the bleb outflow pathway lumen walls for histological visualization and molecular identification using immunofluorescence against lymphatic and blood vessel markers. Bleb outflow pathways could be observed using all tracers in all species. Quantitative analysis showed that the nasal quadrant had more bleb-related outflow pathways compared to the temporal quadrant (nasal: 1.9±0.3 pathways vs. temporal: 0.7±0.2 pathways; p = 0.003). However, not all blebs resulted in an outflow pathway (0-pathways = 18.2%; 1-pathway = 36.4%; 2-pathways = 38.6%; and 3-pathways = 6.8%). Outflow signal was validated as true luminal pathways using optical coherence tomography and histology. Bicuspid valves were identified in the direction of flow in porcine eyes. Immunofluorescence of labeled pathways demonstrated a lymphatic (Prox-1 and podoplanin) but not a blood vessel (CD31) identity. Therefore, subconjunctival bleb outflow occurs in discrete luminal pathways. They are lymphatic as assessed by structural identification of valves and molecular identification of lymphatic markers. Better understanding of lymphatic outflow may lead to improved eye care for glaucoma surgery and ocular drug delivery.

SPARC Levels Modulate the Capacity of Mitomycin to Inhibit the Proliferation of Human Tenon's Capsule Fibroblasts

Purpose

To evaluate the role of SPARC in the antiproliferation effect of MMC on human Tenon's fibroblasts (HTF).

Method

Sixteen PACG patients aged 59 ± 10 years (31-72 years), including 6 males and 10 females, were recruited. Tenon tissue was harvested during filtering surgery. Cell density was evaluated after MMC application with different concentrations and application times, by which the optimized MMC application modality was determined. MMC, si-SPARC, or SPARC protein was used when needed to evaluate the cell densities under different conditions, by which the role of SPARC in MMC-mediated antifibrotic process was identified.

Results

Considering that the cell densities, as well as SPARC expression on mRNA and protein levels, are relatively stable when the MMC concentration is higher than 0.02% and exposure time longer than 90 s, we chose the MMC application pattern with 0.02% and 90 s as an optimized pattern for the downstream work. Compared to control, the si-SPARC and MMC downregulated the SPARC protein by 91% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (.

Conclusion

This study demonstrates that in HTF, (1) MMC downregulates the expression of SPARC in protein and mRNA levels; (2) SPARC depletion has synergistic effect on the antifibrotic effect of MMC; and (3) reactive oxygen species are the possible mediator in the antifibrotic effect of MMC and si-SPARC.

Silicone Tube Miniature Drainage Device Implanted under Scleral Flap for the Surgical Treatment of Glaucoma

PURPOSE

To evaluate the safety and efficacy of a silicone tube miniature drainage device implanted under scleral flap for the surgical treatment of primary open-angle glaucoma (POAG).

METHODS

This is a non-randomized prospective study. Patients with a minimum follow-up of 12 months were analyzed. Demographic information, preoperative and postoperative data including intraocular pressure (IOP), number of medications and complications were recorded.

RESULTS

A total of 33 eyes of 33 patients were included in the analysis. Mean postoperative follow-up was 29.5 ± 6.9 months (range 18-50 months). The mean preoperative IOP was 25.8 ± 7.3 mmHg and decreased to 14.9 ± 4.3, 14.2 ± 3.4 and 14.9 ± 3.3 mmHg at 1 year, 2 years and last follow-up after surgery. The number of medications was decreased from 3.1 ± 1.3 preoperatively to 0.2 ± 0.7, 0.4 ± 0.9 and 0.4 ± 1.0 at 1 year, 2 years and last follow-up, respectively, after surgery. Only six (18.2%) patients used glaucoma medications at last visit. The complete success rates were 87.9% and 78.6%, respectively, at 1 and 2 years postoperatively. The operation-related complications were rare.

CONCLUSIONS

The silicone tube miniature drainage device implanted under the scleral flap was found to be a relatively safe and effective surgery for the treatment of POAG. Longer follow-up periods and larger sample sizes are expected.

Inhibitive effect of TAK-242 on Tenon's capsule fibroblasts proliferation in rat eyes

AIM

To study the inhibition effect of TAK-242 on the proliferation of rat eye Tenon's capsule fibroblasts via the toll-like receptor 4 (TLR4) signaling pathway.

METHODS

SD rat Tenon's capsule fibroblasts were extracted and cultured, then the cells were divided into normal control group, lipopolysaccharide (LPS) group (10 g/mL LPS) and TAK-242 group (1 µmol/L TAK-242, and 10 µg/mL LPS after 30min). The expressions of TLR4, transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6) in each group were detected by Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Cell proliferation was detected by cell counting kit-8 (CCK-8).

RESULTS

Double immunofluorescent labeling in the extracted cells showed negative keratin staining and positive vimentin staining. Western blot showed that the LPS group had the highest expression of TLR4 and TGF-β1 (P<0.01). Enzyme linked immunosorbent assay (ELISA) also showed that the secretion of IL-6 was the highest in LPS group (P<0.01). But there was no significant difference in TLR4 and TGF-1, as well as IL-6 expressions between the TAK-242 group and the normal control group (P>0.05). RT-PCR showed that the IL-6 mRNA expression in LPS group was the highest in the three groups (P<0.01).

CONCLUSION

TAK-242 inhibits the proliferation of LPS-induced Tenon's capsule fibroblasts and the release of inflammatory factors by regulating the TLR4 signaling pathway, providing a new idea for reducing the scarring of the filter passage after glaucoma filtration surgery.

Semi-permanent transcorneal filter support and in vivo surgical implantation technique for open-angle glaucoma treatment

Primary open-angle glaucoma is a progressive disease affecting nearly 60 million people worldwide which, if left untreated, can lead to optic nerve head damage and complete loss of sight. Current interventions include: pharmaceutical drops, laser surgery, shunts, and bleb; however, these methods provide insufficient long-term efficacy in intraocular pressure management. We developed a semi-permanent, implantable transcorneal duct as a new aid in the treatment of this disease. The duct, composed of an intracorneal stabilizing washer and hollow screw, creates an interface between the anterior chamber and the external environment, allowing for the outflow of excess aqueous humor. We discuss the fluid mechanics behind designing and implementing a filter material capable of preventing the ingress of bacteria and viruses while modifying aqueous humor outflow resistances to pre-glaucomatous levels, finding the effective radius of such a material to be 10.44 μm. After performing surgical implantation in four rabbit eyes, subsequent testing showed successful integration between the screw and washer. Colored saline injections highlighted fluid flow progression out of the eye through the duct, suggesting that the device may be a viable approach to treating high intraocular pressure created by open-angle glaucoma.

Anterior Chamber Sulfur Hexafluoride (SF6) Injection for the Management of Postsurgery Hypotony in Glaucoma Patients

PURPOSE

The purpose of this article was to describe a new technique involving the injection of sulfur hexafluoride (SF6) gas in the anterior chamber (A/C) for the management of hypotony in patients with previous glaucoma surgery.

MATERIALS AND METHODS

Seven patients were included in this prospective case series. All patients had advanced glaucoma that was managed surgically either by trabeculectomy (6 patients) or Ahmed valve (1 patient). All patients presented with intraocular pressure (IOP) <7 mm Ηg, shallow A/C, and ultrasound images of choroidal detachment and ciliary body detachment. Patients' hypotony was treated by 0.4 to 0.6 mL of 100% pure SF6 injection in the A/C followed by supine posture. The purpose of this injection was dual: to displace the ciliary body to its normal position and restore aqueous humor normal production, and to block aqueous humor outflow through bubble formation, causing an increase in IOP.

RESULTS

Surgical technique was successful in all 7 patients with IOP normalization (>10 mm Hg) and A/C depth increase within the first week after surgery.

CONCLUSION

A new surgical technique of SF6 injection in the A/C for patients with choroidal detachment and hypotony shows promising results.

Ologen implant versus mitomycin-C for trabeculectomy: A meta-analysis

AIM

To evaluate the efficacy and safety of trabeculectomy (Trab) with mitomycin-C (MMC) versus Trab with implant.

METHODS

Studies published in different languages were retrieved by systematically searching Embase, PubMed, Cochrane library, China Biology Medicine disc, and Google Scholar from 1966 to April 2018, as well as manually examining the references of the original articles. The outcome measures of efficacy covered intraocular pressure, glaucoma medications reductions, and success rate. Safety evaluation was measured by relative ratio of complications.

RESULTS

A total of 11 studies involving 443 participants were covered in this meta-analysis. The weighted mean difference (WMD) in the percentage of intraocular pressure (IOP) reduction (IOPR%) comparing Ologen group with MMC group was -3.69 (95% CI: -6.70 to -0.68) at 1 month, -2.69 (-5.17 to -0.21) at 3 months, -3.67 (-6.09 to -1.25)at 6 months, -3.24 (-6.08 to -0.41) at 12 months, 1.24 (-9.43 to 11.90) at 24 months, and 1.10 (-10.11 to 12.31) at 60 months, which showed that there was statistically significant difference at 1,3, 6, and12 months after the surgery. A significantly higher incidence of postsurgery hypotony (0.64 (95% Cl: 0.42 to 0.98)) and suture lysis (0.30 (95% CI: 0.10-0.93)) was observed in MMC group. However, there was no significant difference in the reduction in glaucoma medications, success rate, and incidence of other complications.Trab with 0.2 mg/mL MMC presented higher rates of complete success compared with Trab with 0.4 mg/mL MMC (P = .01).

CONCLUSION

Trab with MMC was associated with a higher IOP-lowering efficacy and a higher incidence of postsurgery hypotony and suture lysis in contrast to that of Trab with Ologen.

HDAC Inhibitors: Therapeutic Potential in Fibrosis-Associated Human Diseases

Fibrosis is characterized by excessive deposition of the extracellular matrix and develops because of fibroblast differentiation during the process of inflammation. Various cytokines stimulate resident fibroblasts, which differentiate into myofibroblasts. Myofibroblasts actively synthesize an excessive amount of extracellular matrix, which indicates pathologic fibrosis. Although initial fibrosis is a physiologic response, the accumulated fibrous material causes failure of normal organ function. Cardiac fibrosis interferes with proper diastole, whereas pulmonary fibrosis results in chronic hypoxia; liver cirrhosis induces portal hypertension, and overgrowth of fibroblasts in the conjunctiva is a major cause of glaucoma surgical failure. Recently, several reports have clearly demonstrated the functional relevance of certain types of histone deacetylases (HDACs) in various kinds of fibrosis and the successful alleviation of the condition in animal models using HDAC inhibitors. In this review, we discuss the therapeutic potential of HDAC inhibitors in fibrosis-associated human diseases using results obtained from animal models.

Early Detection of Glaucomatous Visual Field Progression Using Pointwise Linear Regression With Binomial Test in the Central 10 Degrees

PURPOSE

We previously reported that it was beneficial to apply binomial pointwise linear regression (PLR) to detect 24-2 glaucomatous visual field (VF) progression, compared to mean deviation (MD) trend analysis and permutation analysis of PLR (PoPLR). The purpose of the current study was to validate the usefulness of the binomial PLR method to detect VF progression in the central 10 degrees in glaucoma patients.

DESIGN

Reliability assessment.

METHODS

A series of 15 VFs (Humphrey Field Analyzer 10-2 SITA-standard) from 97 eyes in 69 primary open-angle glaucoma patients, obtained over 8.5 ± 1.3 years (mean ± SD), were investigated. PLR was performed by regressing the total deviation of all test points on the series of 15 VFs. VF progression was determined from the analyses of VF test points using the binomial test (1-sided, P < .025). The time needed to detect VF progression was also investigated. The results were compared with PoPLR and MD trend analyses.

RESULTS

The binomial PLR was comparable to PoPLR and MD trend analyses in the positive predictive value (0.19 to 0.80), the negative predictive value (0.86 to 1.0), and the false positive rate (0.0 to 0.13) to evaluate glaucomatous VF progression. The time needed to detect VF progression (4.2 ± 1.8 years) was significantly shorter with the binomial PLR method compared with PoPLR and MD trend analysis (P = .04, P = .012, respectively).

CONCLUSIONS

The binomial PLR method detected glaucomatous VF progression in the central 10 degrees significantly earlier than PoPLR and MD trend analyses.

Canaloplasty in the Treatment of Open-Angle Glaucoma: A Review of Patient Selection and Outcomes

Canaloplasty is a relatively new non-penetrating surgery for the reduction of intraocular pressure in patients affected by glaucoma. The technique uses a microcatheter to perform a 360 º cannulation of Schlemm’s canal and leaves in place a tension suture providing an inward distension. It aims to restore the physiological outflow pathways of the aqueous humour and is independent of external wound healing. Several studies have shown that canaloplasty is effective in reducing intraocular pressure and has a low rate of complications, especially compared with trabeculectomy, the gold standard for glaucoma surgery. Currently, canaloplasty is indicated in patients with open-angle glaucoma, having a mild to moderate disease, and the combination with cataract phacoemulsification may provide further intraocular pressure reduction. This article reviews canaloplasty indications, results and complications and analyses its outcomes compared with traditional penetrating and non-penetrating techniques.

The effect on wound healing of pazopanib and bevacizumab compared with corticosteroid in experimental glaucoma filtration surgery

AIM

To compare the effects of bevacizumab and pazopanib with corticosteroids on wound healing after trabeculectomy.

METHODS

In the study, 35 New Zealand white rabbits were randomly divided into five groups. Apart from the first group, limbus-based trabeculectomy was performed for the eyes of rabbits. No postoperative treatment was administered for group I. Topically administered saline, prednisolone acetate (1%), bevacizumab 5 mg/mL, pazopanib 5 mg/mL for group II, III, IV and V respectively were applied for groups 6h daily for 28d. On day 28 of the experiment, eyes were enucleated and histologically and immunohistochemically analyzed.

RESULTS

The fibroblast counts of groups IV and V were determined to be lower than those of groups II and III (P<0.05). In the mononuclear cell (MNC) count evaluation, no statistically significant difference was determined between the treatment groups (P>0.05). The immunohistochemical staining intensity of fibroblast growth factor β (FGF-β) and vascular endothelial growth factor (VEGF) was determined to be lower in groups IV and V than in groups II and III (P<0.05). No statistically significant difference was determined between groups IV and V in respect of fibroblast count, MNC count, FGF-β and VEGF staining intensity (P>0.05). The platelet derived growth factor β (PDGF-β) intensity was lower in group V than in groups II, III and IV (P<0.05). While the PDGF-β staining intensity was significantly lower in group IV than in group II, the difference compared with group III was not statistically significant (P>0.05).

CONCLUSION

Bevacizumab and pazopanib might be good alternatives of corticosteroid treatment on delaying wound healing in glaucoma surgery.

[Glaucoma surgery: from traditional filtration techniques to modern principles of bioengineering]

The article reviews the history of glaucoma surgery and analyses the connection between the accumulation of knowledge on glaucoma progression and the emergence of effective surgical treatment methods based on glaucoma pathogenesis. It also describes modern principles of preventing filtering bleb scarring. Particular attention is devoted to biodegradable collagen matrix implants.

Cataract extraction after deep sclerectomy and its effect on intraocular pressure control

PURPOSE

To estimate the incidence and predisposing factors for cataract extraction (CE) after Deep Sclerectomy (DS) with Mitomycin-C (MMC) and its effect on intraocular pressure (IOP) control.

METHODS

Retrospective study of phakic eyes which had DS with MMC performed over a 5-year period. 179 eyes of 179 patients were included.

RESULTS

Mean age at time of DS was 68.6 ± 9.7 years and mean follow-up was 89.4 ± 29.4 months. 63 eyes had CE and the probability of CE following DS was 0% at 1, 11.6% at 3, 21.0% at 5 and 33.2% at 7 years, with a 50% probability (median survival time) of 10 years. Age was association with increased risk for CE (Hazard ratio 1.05, 95% CI: 1.03-1.08, p < 0.0001). Mean IOP had increased from 11 mmHg to 15 mmHg in the first 3 months and remained higher up to a year (p < 0.001). There was no difference in the probability of maintaining an IOP < 16 mmHg without additional medications or needle revision (p = 0.05,Log-rank test). 20/47 eyes that failed were from the CE group, of which 14 (22.2%) failed prior to CE. Number of eyes on glaucoma medications before CE was 6 (mean edications 0.2 ± 0.5 m) and by last follow-up, 9 eyes were on medications (mean medications 0.2 ± 0.7). Post-CE needle revision was performed on 4 eyes.

CONCLUSIONS

The probability of CE after DS is low, with a gradual increase with time. Increasing age was found to be a statistically significant risk factor. There was a modest increase in IOP after CE and increase use of glaucoma medications.

Relationship between filtering bleb vascularization and surgical outcomes after trabeculectomy: an optical coherence tomography angiography study

PURPOSE

To explore the relationship between the bleb vasculature and surgical outcome after trabeculectomy (TRAB) using optical coherence tomography angiography (OCT-A).

METHODS

A prospective study was conducted, which included 26 eyes of 26 primary glaucoma patients in the final analysis. Thereinto, six patients underwent TRAB combined 5-FU and 12 patients received subconjunctival 5-FU injection postoperation. The bleb vessel was evaluated using OCT-A 1 week, 2 weeks, 1 month, 3 months, and 6 months after TRAB. Intraocular pressure (IOP), filtering bleb height, and bleb wall thickness were recorded at the same time. Pearson's correlation analysis and linear regression analysis were performed to determine the correlation of the vessel area data with other parameters.

RESULTS

Compared with vessel area 1 week after surgery, there was significant increase of the vessel area (△vessel area) 2 weeks (11.13 ± 11.91%, p < 0.05) and 1 month (16.91 ± 14.85%, p < 0.0001) after surgery in all patients. The △vessel area was significantly greater in acute angle closure (AAC) and primary angle closure glaucoma (PACG) 1-month post-TRAB as compared with that 1 week (p < 0.05). The results indicated that the △vessel area 1-month post-TRAB was positive correlated with IOP 6-month post-TRAB (β = 3.88, p = 0.042).

CONCLUSIONS

Filtering bleb vascularization evaluation using OCT-A could potentially predict IOP 6-month post-TRAB. Surgery effect predicted by filtering bleb vascularization detection is conducive to the select specific postoperative intervention to improve the success rate of TRAB.

Treatment Outcomes of Mitomycin C-Augmented Trabeculectomy, Sub-Tenon Injection versus Soaked Sponges, after 3 Years of Follow-up: A Randomized Clinical Trial

PURPOSE

To report the 3-year outcome of trabeculectomy with mitomycin C (MMC)-soaked sponges versus intra-Tenon injection of MMC in eyes with uncontrolled primary open-angle glaucoma.

DESIGN

Randomized clinical trial.

PARTICIPANTS

Eighty-two consecutive patients with uncontrolled primary open-angle glaucoma.

METHODS

Participants were randomized either to intra-Tenon injection of 0.1 ml of 0.01% MMC (TI group) or 0.02% subconjunctival application of MMC-soaked sponges (TS group). Patients were followed up for 3 years after surgery. The data for 73 eyes were included in the final analysis.

MAIN OUTCOME MEASURES

The primary outcome measure was the surgical success, defined as intraocular pressure (IOP) more than 5 mmHg and <21 mmHg, and IOP reduction of 20% or more from baseline, no reoperation for glaucoma, and no loss of light perception vision. Secondary outcome measures were IOP, glaucoma medications, best-corrected visual acuity (VA), bleb morphologic features according to the Indiana Bleb Appearance Grading Scale, complications, and endothelial cell count changes.

RESULTS

The cumulative probability of success at 3-year follow-up was 72.2% in the TI group and 65.1% in the TS group (P = 0.30). Uncontrolled IOP was the most common reason for failure. The mean preoperative IOP was 22.4±4.6 mmHg with an average of 3.1±1.0 medications. At 3 years, final IOP was 15.3±3.7 mmHg in the TI group and 16.4±3.5 mmHg in the TS group (P = 0.55). Mean glaucoma number of medications was 0.9±1.1 and 1.1±1.1 in the TI and TS groups, respectively (P = 0.54). Blebs tended to be more diffuse (P = 0.032), less vascularized (P = 0.013), and more shallow (P = 0.012) after intra-Tenon injection. Visual outcomes and endothelial cell changes were similar in both groups (P = 0.47 and P = 0.94, respectively).

CONCLUSIONS

Although the success rate and IOP reduction were comparable with both techniques, bleb morphologic parameters were more favorable after intra-Tenon injection of 0.1 ml of 0.01% MMC.

Exploring literature-based definitions of hypotony following glaucoma filtration surgery and the impact on clinical outcomes

PURPOSE

To highlight the variations in published definitions of hypotony and their impact on reported clinical outcomes. To propose a revised definition, focusing on clinically significant hypotony (CH).

METHODS

Literature review of hypotony definitions published between January 2010 and December 2015 was carried out. Numerical definitions for hypotony, its onset, duration and associated clinical signs were recorded. Each definition was applied to surgical outcomes data collected prospectively from a cohort of 300 glaucoma patients treated at a single centre. The sensitivity and specificity of each definition in identifying CH [defined as low intraocular pressure (IOP) with signs of maculopathy hypotony and choroidal detachment] were calculated.

RESULTS

A total of 128 eligible papers were identified, and 14 different definitions for hypotony were extracted. In 53 (41.4%), hypotony was not defined. In the remaining 75 (58.6%), the numerical definitions varied between 4 and 8 mmHg, and of these, 24 (32%) included the onset and duration of hypotony as part of the definition. Definition-dependent hypotony rates within the cohort varied between 1% and 59.3%. No statistical differences were found between the groups based on corneal thickness or axial length. Clinically significant hypotony (CH) was identified in 37 (12.3%), with large differences in the sensitivity and specificity among published definition.

CONCLUSION

Variations in defining postoperative hypotony can have a large impact on the reported success and failure rates among studies. There is a need for a more robust universal definition, focusing on clinically important signs, to allow better comparison between different treatment modalities.

Stegmann Canal Expander for canaloplasty: A novel technique

Introduction:

The concept of canaloplasty is to increase aqueous egress through all structures that control the aqueous outflow, such as the trabecular meshwork, Schlemm’s canal, and collector channels, by viscomodulation and by placing of a suture stent into the canal. Clinical studies show canaloplasty to be safe and efficient in lowering the intraocular pressure; however, proper knotting of the tensioning suture is technically challenging and even impossible if circumferential cannulation cannot be achieved; furthermore, protrusion of the suture stent is a potential lifelong risk.

Methods:

The specific design of the Stegmann Canal Expander allows a permanent expansion of the canal and distension of the trabecular meshwork. Two expanders are implanted on either side of the surgically created ostium of Schlemm’s canal to treat half of the circumferential outflow system. This article describes the technique step by step, provides the clinician with surgical pearls, and highlights the management of adverse events.

Results:

Technically, implantation of the Stegmann Canal Expander is simple and does not require a long learning curve, compared to placing and knotting a tensioning suture. Most issues are related to the two-flap dissection technique (deep sclerectomy technique) and not to implantation of the Stegmann Canal Expander. Intraocular pressure reduction without medications to the low teens can be achieved.

Conclusions:

The Stegmann Canal Expander is a novel micro-device that has the potential to make canaloplasty a simplified, more controlled, and reproducible surgical procedure.