Victorian trabeculectomy audit

TGFβ1-Induced Fibrotic Responses of Conjunctival Fibroblasts through the Wnt/β-Catenin/CRYAB Signaling Pathway

Conjunctival fibrosis is a common postoperative complication of glaucoma filtration surgery, resulting in uncontrolled intraocular pressure and surgery failure. Therefore, there is an urgent need to understand the molecular mechanisms underlying conjunctival fibrosis and to explore novel pharmacologic anti-fibrosis therapies for glaucoma filtration surgery. Herein, the 4-dimensional data-independent acquisition (4D-DIA) quantitative proteomic results, coupled with experimental data, revealed the activation of the Wnt/β-catenin pathway in transforming growth factor (TGF)-β1-induced human conjunctival fibroblasts (HConFs). Treatment with ICG-001, a Wnt/β-catenin inhibitor, effectively inhibited cell proliferation and migration in TGFβ1-treated HConFs. ICG-001 treatment alleviated the increased generation of extracellular matrix proteins induced by TGFβ1. In addition, ICG-001 reduced the expression level of α smooth muscle actin (α-SMA) and inhibited cell contractility in TGFβ1-treated HConFs. Proteomics data further suggested that αB-crystallin (CRYAB) was a downstream target of Wnt/β-catenin, which was up-regulated by TGFβ1 and down-regulated by ICG-001. Immunoblotting assay also indicated that ICG-001 reduced the expressions of ubiquitin and β-catenin in TGFβ1-treated HConFs, implying that CRYAB stabilized β-catenin by inhibiting its ubiquitination degradation. Exogenous CRYAB promoted cell viability, increased extracellular matrix protein levels, and up-regulated α-SMA expression of HConFs under TGFβ1 stimulation. CRYAB rescued TGFβ1-induced fibrotic responses that were suppressed by ICG-001. In conclusion, this study elucidates the regulatory mechanism of the Wnt/β-catenin/CRYAB pathway in conjunctival fibrosis, offering promising therapeutic targets for mitigating bleb scarring after glaucoma filtration surgery.

12-month Safety and Efficacy Outcomes of a Standalone Trabecular Bypass Device

Purpose

To analyze the outcomes of the iStent inject in a real-world clinical setting as a standalone procedure to lower intraocular pressure (IOP) in open-angle glaucoma.

Materials and methods

Patients with open-angle glaucoma having undergone iStent inject insertion without concurrent cataract extraction were included in this multicenter observational real-world study in Australia. Patient data was entered into the Fight Glaucoma Blindness! Registry. Assessments through 12 months included glaucoma subtype, IOP, medications, best-corrected visual acuity (BCVA), secondary surgical procedures, and adverse events. Kaplan-Meier survival curves for outcomes were reported according to the World Glaucoma Association (WGA).

Results

Sixty-one eyes from 44 patients with a mean age of 76 ± 11.4 underwent standalone iStent inject implantation. The mean ± SD preoperative IOP was 17.5 ± 7.5 mm Hg, and the mean preoperative number of topical medications was 2.5 ± 1.5. At 12 months postoperatively, there was no statistically significant IOP reduction, while the number of glaucoma medications used was reduced to 1.4 ± 1.5 (p < 0.001). Fourteen point one percent of eyes required a secondary pressure-lowering procedure within the 12-month follow-up window.

Conclusion

This assessment of standalone iStent inject implantation did not show any significant reduction in IOP, but there was a significant decrease in medication use in the real-world clinical setting. The procedure is safe with minimal adverse outcomes; however, a subset of patients required secondary procedures within 12 months of follow-up.

How to cite this article

Huynh B, Clement C, Nguyen V, et al. 12-month Safety and Efficacy Outcomes of a Standalone Trabecular Bypass Device. J Curr Glaucoma Pract 2024;18(3):103-109.

Long-Term Safety and Outcomes of β-radiation for Trabeculectomy

PRCIS

β-radiation is a neglected antiscarring therapy with past concerns for safety. This report found it safe and efficacious when used as an adjuvant to trabeculectomy surgery in 101 people (135 eyes) over 20 years.

PURPOSE

β-radiation has been used as an adjunct to prevent scarring in trabeculectomy surgery for many decades. Safety concerns were raised with the use of high doses on the bare sclera. Moorfields Eye Hospital has a large cohort of patients who have received β-radiation therapy. We report a review of the long-term safety and efficacy.

METHODS

Cases undertaken between August 1992 and August 1996 were reviewed. Those with records available for postoperative review of more than 5 years were included. Failure (reintervention/>21 mm Hg on 2 successive occasions) and any complication previously reported in association with β-radiation were the primary outcomes.

RESULTS

In total, 292 operations using β-radiation were recorded and 101 people (135 eyes) with trabeculectomy surgery and postoperative follow-up for over 4.5 years were included. The median follow-up period was 22.5 years. At the final follow-up, 48 (48%) single eyes per person had failed and 20/51 (51%) eyes with primary open angle glaucoma had cataract surgery. Other complications were rare and associated with copathology.

CONCLUSION

In glaucoma patients at risk of scarring and failure after trabeculectomy, as an antiscarring adjuvant, a 750 cGY dose of β-radiation was found to be safe and efficacious in the long term.

Current management of glaucoma

Glaucoma is an irreversible progressive optic neuropathy, for which the major proven treatment is to lower the intraocular pressure (IOP). Five groups of IOP-lowering eye drops have varying mechanisms of action. Some drops, such as β-blockers and α-2 agonists, have potentially serious systemic side effects. Acetazolamide is the only available oral agent; it is effective at lowering IOP, but significant side effects relegate its use usually to refractory glaucoma. Two new eye drops, netarsudil and latanoprostene bunod, have recently been approved by the United States Food and Drug Administration. Both have novel IOP-lowering mechanisms and target the conventional aqueous outflow system. Selective laser trabeculoplasty is a gentle treatment that enhances conventional aqueous outflow. It may be used as an initial treatment, as a substitute for eye drops, or to delay glaucoma drainage surgery. Recent advancements in glaucoma surgery have seen an influx of minimally invasive glaucoma surgery devices, which are being used more frequently and earlier on in the treatment paradigm. As limited long term data are available, trabeculectomy remains the gold standard IOP-lowering procedure. Improvements in drug delivery are on the horizon. Drug-eluting devices and implants are able to deliver the drug closer to the receptors for an extended period of time. This will improve treatment adherence and efficacy, which are major limitations with current medical therapy.

Success of trabeculectomy surgery in relation to cataract surgery: 5-year outcomes

AIMS

To compare success proportions at 5 years in three surgical groups: group 1, trabeculectomy alone; group 2, trabeculectomy followed by cataract surgery within 2 years; and group 3, trabeculectomy performed on a pseudophakic eye.

METHODS

A retrospective cohort study. 194 eyes of 194 patients were identified with at least 5 years' follow-up post trabeculectomy (N=85, 60 and 49 in groups 1, 2 and 3, respectively).

MAIN OUTCOME MEASURES

1.

PRIMARY OUTCOME MEASURE

intraocular pressure (IOP) at 5 years post-trabeculectomy surgery, 2.Secondary outcome measure: change in visual acuity at 5 years.

RESULTS

At 5 years, the mean IOP (SD) was 12.9 (3.5), 12.5 (4.8) and 12.7 (4.8) mm Hg in groups 1, 2 and 3, respectively. Overall success was almost identical, 58%, 57% and 59% in groups 1, 2 and 3, respectively. There was no significant difference between the groups in terms of percentage IOP reduction, number of medications, proportion restarting medication and reoperation rates at 5 years. Logistic regression for an outcome of failure showed men to be at increased risk of failure OR 1.97 (95% CI 1.10 to 3.52, p=0.02). Nearly 80% of patients retained or improved their vision following their initial trabeculectomy.

CONCLUSIONS

The sequence in which surgery is carried out does not appear to affect trabeculectomy function at 5 years, success being similar to trabeculectomy alone. In our study, men may be at increased risk of failure.