Australia and New Zealand Survey of Antimetabolite and Steroid Use in Trabeculectomy Surgery

The Effect of CHIR 99021, a Glycogen Synthase Kinase-3β Inhibitor, on Transforming Growth Factor β-Induced Tenon Fibrosis

Purpose

This study investigated the effect of glycogen synthase kinase-3β (GSK-3β) inhibition on the fibrosis of human Tenon's fibroblasts (HTFs) induced by transforming growth factor-β (TGF-β).

Methods

Quantitative real-time PCR and Western blot analyses were performed to determine the expression levels of molecules associated with the fibrosis of HTFs by TGF-β (fibronectin, collagen Iα, and α-smooth muscle actin) and GSK-3β. The levels of phosphorylated Smad2 and Smad3 were also analyzed in the presence of the GSK-3β inhibitor CHIR 99021. The wound healing assay was performed to determine the effect of CHIR 99021 on the migration of HTFs. All experiments were conducted using primary cultured HTFs or human tenon tissues obtained from normal subjects and patients with glaucoma.

Results

Treatment with TGF-β resulted in an increase in the levels of molecules associated with the fibrosis of HTFs. The expression levels of these molecules were higher in the tenon tissues obtained from patients with glaucoma than those from normal subjects. When the HTFs were treated with TGF-β, a significant increase in the active form of GSK-3β (Y216) was observed. A significant decrease in the active form of GSK-3β and molecules associated with fibrosis by TGF-β was noted in HTFs treated with CHIR 99021. CHIR 99021 treatment reduced the phosphorylated Smad2/Smad2 and phosphorylated Smad3/Smad3 ratios in HTFs and attenuated HTF migration.

Conclusions

Our results demonstrated the effect of GSK-3β inhibition on the regulation of TGF-β–mediated fibrosis of HTFs, suggesting GSK-3β to be a potential target for maintaining bleb function after glaucoma filtration surgery.

Learning from the past: Mitomycin C use in trabeculectomy and its application in bleb-forming minimally invasive glaucoma surgery

Trabeculectomy has been performed since the mid-1960s and remains the gold standard for glaucoma surgery. Newer surgical options have evolved, collectively referred to as minimally invasive glaucoma surgeries. Despite producing large intraocular pressure decreases, full-thickness procedures into the subconjunctival space may be limited by fibrosis. Mitomycin C (MMC) and 5-fluorouracil have been in use with trabeculectomy with good evidence of significantly increased success at the cost, however, of an increased risk of complications. Off-label MMC application can be found in almost all clinical trials, including in combination with minimally invasive glaucoma surgeries. We explore current evidence for MMC use in trabeculectomy and how this may differ for minimally invasive glaucoma surgery devices and analyze the range of agents and doses that are used. Although we found that most studies could not show any correlation between MMC dosage and the surgical outcome, the success rates with the Xen® microshunt seemed to be higher when using 20 mcg of MMC than when using 10 mcg. Certain important methodological considerations make this hard to confirm definitively, and other factors such as placement of the device may play a more substantial role. For the PreserFlo® microshunt, preliminary data suggest higher success rates with higher MMC dosage at the cost of higher device-related adverse events and reoperations. Although the ideal dose still needs to be established, it seems very likely that MMC provides significant improvement in outcomes in bleb-forming minimally invasive glaucoma procedures.

Bleb-associated endophthalmitis: Proportion, presentation, management and outcomes in Victoria, Australia

IMPORTANCE

Bleb-associated endophthalmitis is a potentially vision-threatening complication of trabeculectomy. With improvements in surgical technique and changing patterns of intraoperative antimetabolite use, a re-evaluation of the incidence of bleb-associated endophthalmitis is warranted.

BACKGROUND

To investigate changes in the incidence, presentation, management and outcomes of bleb-associated endophthalmitis between 1997 and 2015 in Victoria, Australia.

DESIGN

A retrospective cohort analysis.

PARTICIPANTS

Consecutive cases of bleb-associated endophthalmitis managed at the Royal Victorian Eye and Ear Hospital (RVEEH) between 1997 and 2015.

METHODS

Medical record review of consecutive cases of bleb-associated endophthalmitis and statistical analysis were performed.

MAIN OUTCOME MEASURES

Visual acuity, including loss of light perception, intraocular pressure, and need for further surgery.

RESULTS

Sixty-seven eyes with bleb-associated endophthalmitis (BAE) were identified. Of these, 41 had trabeculectomy performed in Victoria during the study period, over which time 11 129 trabeculectomies were performed. The proportion of BAE was stable over time (0.4%). The mean age at presentation was 73.7 ± 12.1 years old and the majority of patients were Caucasian (79.1%). The mean duration between glaucoma filtration surgery and the development of bleb-associated endophthalmitis was 3 years (Interquartile Range = 0.4-6.0 years). The cultures were positive in 71.6% of cases. Approximately 1 in 8 patients required enucleation. The final visual acuity was poor with a Snellen Visual Acuity (VA) of 6/60 or worse in two-thirds of patients.

CONCLUSIONS AND RELEVANCE

Bleb-associated endophthalmitis is an uncommon complication following glaucoma filtration surgery. The proportion has remained stable over time. Visual outcomes remain poor.

Impact of Topically Administered Steroids, Antibiotics, and Sodium Hyaluronate on Bleb-Related Infection Onset: The Japan Glaucoma Society Survey of Bleb-Related Infection Report 4

Purpose

To investigate the impact of topically administered ophthalmic medications on the onset and severity of bleb-related infections.

Methods

Data obtained from 104 eyes of 104 patients with bleb-related infections were analyzed. We assigned an infection stage to each eye (stage 1-4) and analyzed the onset severity.

Results

Steroids and antibiotics were routinely administered to 13 (12.5%) and 42 (40.4%) eyes, respectively. The median stage of steroid-administered eyes was 3 versus 1 for eyes without steroid administration (P = 0.012). The median duration from surgery to infection for the steroid-administered eyes was 2.0 years versus 5.8 years for eyes without steroid administration (P = 0.030). The median duration from surgery to infection for the antibiotic-administered eyes was 6.4 years versus 3.9 years for eyes without antibiotic administration (P = 0.025). Multiple logistic regression analysis revealed that infections were severe in the steroid-administered eyes (odds ratio: 4.57). No infections developed within 16 weeks postoperatively. No relationship was detected between sodium hyaluronate and the analyzed factors.

Conclusions

Topical steroid administration beyond the immediate postoperative period may affect severe and earlier onset bleb-related infections. Conversely, topical antibiotic administration may be effective in suppressing earlier onset bleb-related infections.

[Revision after filtration surgery]

BACKGROUND

In contrast to all other glaucoma surgeries, filtration surgery is associated with biomicroscopically visible wound healing, which enables the surgeon to perform revision surgeries if necessary.

OBJECTIVES

The aim of this review is to provide general considerations and to give a structured overview about bleb revisions after trabeculectomy.

MATERIALS AND METHODS

The different revision techniques are explained in detail and in the context of perioperative management.

RESULTS

Preoperative preparation and modifications of the surgical techniques reduce the incidence of postoperative revisions. The site of the fibrosis defines the revision technique (bleb needling, needle revision, bleb revision with reopening). The increased percolation rate of aqueous humor in postoperative hypotony contributes to fibrosis and may lead to maculopathy, choroidal effusion, and suprachoroidal hemorrhage.

DISCUSSION

Discontinuing administration of local medication and pretreatment with steroids without preservative for at least one week prior to surgery increase surgical success of trabeculectomy and reduce the incidence of postoperative revisions. Postoperative management after filtration surgery should be performed after consulting the surgeon. The primary endpoint of trabeculectomy is an intraocular pressure between 8 and 12 mm Hg without local antiglaucomatous medication. In postoperative hypotony revisions should be done earlier and based on the pathological findings.

Prevalent practice patterns in glaucoma: Poll of Indian ophthalmologists at a national conference

Purpose:

The aim of this study is to explore and compare the prevailing practice patterns in the diagnosis and management of glaucoma among subspecialists and general ophthalmologists in India.

Materials and Methods:

This is an interactive audience response system (ARS) based poll of ophthalmologists attending the annual conference of the Glaucoma Society of India in 2013.

Results:

The information was obtained from 379 ophthalmologists (146 glaucoma specialists, 54 nonglaucoma subspecialists, and 179 general ophthalmologists). The majority of polled ophthalmologists (236; 62%) had 10 or more years of experience in ophthalmology. The glaucoma specialists differed from nonglaucomatologists in their preference for Goldmann applanation tonometer (P < 0.01), four-mirror gonioscope (P < 0.01), Humphrey perimeter (P < 0.01), laser peripheral iridotomy in primary angle closure disease (P = 0.03), postiridotomy gonioscopy (P < 0.01), and usage of antifibrotic agents during filtering surgery (P < 0.01). Optical coherence tomography was the most preferred imaging modality and was utilized more often by the subspecialists than general ophthalmologists. The ophthalmologists also differed in their choice of antiglaucoma medications. More glaucoma specialists were performing surgery on children with congenital glaucoma (P < 0.01), implanting glaucoma drainage devices (P < 0.01), and using scientific journals to upgrade knowledge (P = 0.03) than the other ophthalmologists.

Conclusions:

This poll is the first of its kind in India, in its usage of the ARS, and in comparing the practice patterns of care for glaucoma among subspecialists and general ophthalmologists. It has revealed substantial diversity in a few areas among those who did and did not receive specialty training in glaucoma.

Conjunctival fibrosis following filtering glaucoma surgery

Despite advances in surgical technique and postoperative care, fibrosis remains the major impediment to a marked reduction of intraocular pressure without the need of additional medication (complete success) following filtering glaucoma surgery. Several aspects specific to filtering surgery may contribute to enhanced fibrosis. Changes in conjunctival tissue structure and composition due to preceding treatments as well as alterations in interstitial fluid flow and content due to aqueous humor efflux may act as important drivers of fibrosis. In light of these pathophysiological considerations, current and possible future strategies to control fibrosis following filtering glaucoma surgery are discussed.

Perioperative pharmacological management in patients with glaucoma

REVIEẂS AIM: When a phacoemulsification, a filtration surgery or a combined surgery are necessary, questions about the convenience of continuing certain antiglaucomatous drugs could appear. The aim of this review article is to unify criteria that will guide daily clinical practice and including the developing algorithms of action in the preoperative and postoperative periods of filtration surgery and/or cataract surgery.

PROPOSED PROTOCOLS

In the preoperative period of cataract surgery, the use of non-steroidal anti-inflammatory drugs is at the discretion of the surgeon, with the monodose presentation being recommended. The suspension of prostaglandines a fewdays before the surgery should be considered. Preservative-free drugs ensure a better recovery of the ocular surface (OS) after cataract surgery. Once all modifying factors of the intraocular pressure (IOP) have been removed, baseline IOP should be evaluated again, choosing preservative-free antiglaucomatous drugs when needed. The use of preservative-free ocular antihypertensive drugs and steroids in the preoperative period of glaucoma surgery reduces the risk of surgical failure. The interruption of prostaglandines is recommended. In the postoperative period of glaucoma surgery, steroids are the anti-inflammatory treatment of choice, the preservative-free ones being preferred. When reintroducing antiglaucomatous treatment, preservatives should be avoided to prevent scarring. The appropriate perioperative management of patients with glaucoma is essential to obtain a correct control of IOP, improve the situation of the OS, prevent complications and improve the result of the filtration surgery and cataract surgery.

CONCLUSIONS

this protocol aims to unify the different lines of action in order to decrease the incidence of adverse events and maximize the surgical outcome.

Trabeculectomy in the 21st century: a multicenter analysis

OBJECTIVE

To evaluate the efficacy and safety of current trabeculectomy surgery in the United Kingdom.

DESIGN

Cross-sectional, multicenter, retrospective follow-up.

PARTICIPANTS

A total of 428 eyes of 395 patients.

METHODS

Consecutive trabeculectomy cases with open-angle glaucoma and no previous incisional glaucoma surgery from 9 glaucoma units were evaluated retrospectively. Follow-up was a minimum of 2 years.

MAIN OUTCOME MEASURES

Surgical success, intraocular pressure (IOP), visual acuity, complications, and interventions. Success was stratified according to IOP, use of hypotensive medications, bleb needling, and resuturing/revision for hypotony. Reoperation for glaucoma and loss of perception of light were classified as failures.

RESULTS

Antifibrotics were used in 400 cases (93%): mitomycin C (MMC) in 271 (63%), 5-fluorouracil (5-FU) in 129 (30%), and no antifibrotic in 28 (7%). At 2 years, IOP (mean ± standard deviation) was 12.4 ± 4 mmHg, and 342 patients (80%) achieved an IOP ≤ 21 mmHg and 20% reduction of preoperative IOP without IOP-lowering medication, whereas 374 patients (87%) achieved an IOP ≤ 21 mmHg and 20% reduction of preoperative IOP overall. An IOP ≤18 mmHg and 20% reduction of preoperative IOP were achieved by 337 trabeculectomies (78%) without IOP-lowering treatment and by 367 trabeculectomies (86%) including hypotensive medication. Postoperative treatments included suture manipulation in 184 patients (43%), resuturing or revision for hypotony in 30 patients (7%), bleb needling in 71 patients (17%), and cataract extraction in 111 of 363 patients (31%). Subconjunctival 5-FU injection was performed postoperatively in 119 patients (28%). Visual loss of >2 Snellen lines occurred in 24 of 428 patients (5.6%). A total of 31 of the 428 patients (7.2%) had late-onset hypotony (IOP <6 mmHg after 6 months). In 3 of these, visual acuity decreased by >2 Snellen lines. Bleb leaks were observed in 59 cases (14%), 56 (95%) of which occurred within 3 months. Two patients developed blebitis. Bleb-related endophthalmitis developed in 1 patient within 1 month postoperatively and in 1 patient at 3 years. There was an endophthalmitis associated with subsequent cataract surgery.

CONCLUSIONS

This survey shows that good trabeculectomy outcomes with low rates of surgical complications can be achieved, but intensive proactive postoperative care is required.

The singapore 5-Fluorouracil trabeculectomy study: effects on intraocular pressure control and disease progression at 3 years

PURPOSE

To report 3-year results of a randomized, controlled trial comparing the use of a single application of 5-fluorouracil (5-FU) with placebo in trabeculectomy surgery.

DESIGN

Prospective, randomized, double-blinded treatment trial.

PARTICIPANTS

Two hundred forty-three Asian patients with primary open-angle or primary angle-closure glaucoma undergoing primary trabeculectomy.

METHODS

One eye of each patient was randomized to receive either intraoperative 5-FU or normal saline (placebo) during trabeculectomy.

MAIN OUTCOME MEASURES

Primary outcome measure was the level of intraocular pressure (IOP). Secondary outcomes were progression of visual field loss, rates of adverse events, and interventions after surgery.

RESULTS

Of the 288 eligible patients, 243 were enrolled and 228 completed 3 years follow-up; 120 patients received 5-FU and 123 received placebo. Trial failure, according to predefined IOP criteria, was lower in the 5-FU group compared with the placebo group, although the difference was only significant with a failure criterion of IOP >17 mmHg (P = 0.0154). There was no significant difference in progression of optic disc and/or visual field loss over 36 months between 5-FU and placebo (relative risk [RR], 0.67; 95% confidence interval [CI], 0.34-1.31; P = 0.239). Uveitis occurred more often in the 5-FU-treated group (14/115 [12%] vs 5/120 [4%]; P = 0.032).

CONCLUSIONS

This is the first masked, prospective, randomized trial reporting the effect of adjunctive 5-FU in trabeculectomy surgery in an East Asian population. The trial shows that an increased success rate can be achieved for several years after a single intraoperative treatment with 5-FU. We conclude that 5-FU is relatively safe and can be routinely used in low-risk East Asian patients.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.