Long-term outcomes of needle revision of trabeculectomy blebs with mitomycin C and 5-fluorouracil: a comparative safety and efficacy report

Usefulness of eye deformation in the Corvis ST measurement to predict postoperative hypotony complications in glaucoma

PURPOSE

This study aimed to investigate the usefulness of measuring biomechanical parameters using the Corvis ST to predict the occurrence of hypotony maculopathy and choroidal detachment (CD) following trabeculectomy or bleb needling revision with mitomycin C (MMC).

DESING

Clinical cohort study METHODS: This study included 100 eyes of 100 patients who underwent trabeculectomy (88 eyes of 88 patients) or bleb needling (12 eyes of 12 patients) with MMC. A significant predictor of hypotony complications was identified from 1) operation (trabeculectomy or bleb needling), 2) age, 3) sex, 4) disease type (primary open angle glaucoma [POAG], exfoliation glaucoma [EG] or other), 5) lens status (phakia or pseudophakia), 6) preoperative Goldmann applanation tonometry (GAT) intraocular pressure (IOP), 7) preoperative central corneal thickness (CCT), 8) preoperative axial length (AL), 9) preoperative anterior chamber (AC) depth, 10) "Min IOP" (IOP value when hypotony complications occurred, otherwise the minimum IOP during 3 months from trabeculectomy or bleb needling), 11) preoperative corneal curvature, and 12- 24) 12 Corvis ST parameters using multivariate logistic regression.

RESULTS

There were 13 and 21 eyes developed hypotony maculopathy and CD, respectively. Male gender, greater preoperative GAT IOP and greater HC deflection Amplitude were significant predictors of the occurrence of hypotony maculopathy (p <0.05). On the other hand, shorter axial length, thinner CCT, greater preoperative GAT IOP and pseudophakia were significant predictors of the occurrence of CD (p <0.05).

CONCLUSIONS

A careful attention should be paid to the occurrence of hypotony maculopathy with male gender and greater HC deflection Amplitude despite higher preoperative GAT IOP. Different risk factors were identified; shorter axial length, thinner CCT, greater preoperative GAT IOP and pseudophakia.

Wound modulation in glaucoma surgery: The role of anti-scarring agents

Filtration surgery is one of the most frequently performed surgeries in the management of glaucoma, and trabeculectomy is considered the gold standard surgical technique for the same. Though trabeculectomy has been reported to have an excellent initial success rate, about 30% of them fail in 3 years, and nearly 50% of them fail in 5 years. The most significant risk of failure still seems to be wound scarring, especially episcleral fibrosis, leading to bleb failure. As a result, it is essential to explore the role of anti-scarring agents, including mitomycin C, and 5-fluorouracil in wound modulation and improving the bleb survival rate. Since these agents are widely used in trabeculectomy, it is crucial to understand the various modes of application, advantages, and adverse effects of these agents. On an evidence-based approach, all these points have been highlighted in this review article. In addition, the newer agents available for wound modulation and their scope for practical application are discussed.

Safety and Efficacy of the Rho-Kinase Inhibitor (Ripasudil) in Bleb Needling after Trabeculectomy: A Prospective Multicenter Study

Ripasudil, a rho-associated protein kinase inhibitor ophthalmic solution, shows a protective effect in preventing excessive scarring in vitro. This study aims to evaluate the safety and efficacy of ripasudil for glaucoma patients submitted to the needling procedure. In this prospective, multicenter, single-arm study, we included 20 eyes of 20 patients with glaucoma who underwent the needling procedure without antimetabolites. All patients administered ripasudil after needling for three months. The primary endpoint of this study was the safety of ripasudil in patients, and the secondary endpoint was the change in IOP at 12 weeks after the needling procedure. No serious complications were found in the patients. One eye experienced pruritus and conjunctival follicle, while another eye had conjunctival follicle. These complications were transient and resolved quickly after discontinuation of ripasudil. The mean preoperative IOP was 14.6 ± 4.6 mmHg, which decreased to 11.0 ± 4.7 mmHg (p = 0.0062) at 1 week postoperatively. The IOP reduction effect continued to 12 weeks (11.8 ± 3.1 mmHg; p = 0.0448). The administration of the ROCK inhibitor, ripasudil, after the needling procedure is safe and effective in maintaining IOP for 12 weeks.

A Degradable Sustained-Release Drug Delivery System for Bleb-Forming Glaucoma Surgery

Fibrosis of the filtering bleb is one of the main causes of failure after bleb-forming glaucoma surgery. Intraoperative application of mitomycin C (MMC) is the current gold standard to reduce the fibrotic response. However, MMC is cytotoxic and one-time application is often insufficient. A sustained-release drug delivery system (DDS), loaded with MMC, may be less cytotoxic and equally or more effective. Two degradable (polycaprolactone (PCL) and polylactic-co-glycolic acid (PLGA)) MMC-loaded DDSs are developed. Release kinetics are first assessed in vitro followed by rabbit implants in conjunction with the PRESERFLO MicroShunt. As a control, the MicroShunt is implanted with adjunctive use of a MMC solution. Rabbits are euthanized at postoperative day (POD) 28 and 90. The PLGA and PCL DDSs release (on average) 99% and 75% of MMC, respectively. All groups show functioning blebs until POD 90. Rabbits implanted with a DDS show more inflammation with avascular thin-walled blebs when compared to the control. However, collagen is more loosely arranged. The PLGA DDS shows less inflammation, less foreign body response (FBR), and more complete degradation at POD 90 when compared to the PCL DDS. Further optimization with regard to dosage is required to reduce side effects to the conjunctiva.

A multicenter phase II study on the safety of rho-kinase inhibitor (ripasudil) with needling for the patients after trabeculectomy

Background

There is no established method of maintaining or reducing intra ocular pressure after the needling procedure for failing blebs post trabeculectomy. Regarding newer antihypertensive medications, ripasudil, which is a rho-associated protein kinase inhibitor ophthalmic solution, was able to prevent excessive scarring in vitro. This study aims to evaluate the safety of glaucoma patients submitted to the needling procedure and administered ripasudil for preventing scarring after the procedure. We also investigate the efficacy of ripasudil after needling for bleb failure through suppression of fibrosis to the bleb.

Methods

This study is a multicenter, open-label, single-arm, phase II trial to evaluate the safety and efficacy of ripasudil in glaucoma patients after the needling procedure. Forty patients who will undergo needling at least 3 months after trabeculectomy will be recruited in Hiroshima university hospital and Hiroshima eye clinic. All the patients will instill ripasudil two times per day for three months after the needling procedure. The primary endpoint is the safety of ripasudil.

Conclusions

We plan to establish the safety of ripasudil and to collect information involving the efficacy of ripasudil widely in this study.

Complications and post-operative interventions in XEN45 gel stent implantation in the treatment of open angle glaucoma-a systematic review and meta-analysis

BACKGROUND

The XEN45 Gel Stent is a subconjunctival filtering device that has demonstrated promising efficacy. This meta-analysis quantitatively evaluates reported complications and interventions after XEN45 implantation in the treatment of open angle glaucoma (OAG).

METHODS

Pilot, cohort, observational studies, and randomised controlled trials that included at least ten patients undergoing ab interno or externo XEN45 surgery, with or without phacoemulsification were deemed eligible for inclusion. A meta-analysis of proportions with random-effect models was performed using the meta routine in R version 3.2.1. Outcomes included the rate of complications and post-operative interventions.

RESULTS

One hundred and fifty-two studies were identified on initial literature search and 33 were included in final analysis. Numerical hypotony was the most common post-operative complication, involving 20% of patients (95% CI: 10-31%). Post-operative gross hyphema occurred in 14% (95% CI: 7-22%) and transient intra-ocular pressure (IOP) spikes (>30 mmHg) in 13% (95% CI: 4-27%). Stent exposure occurred in 1% (95% CI: 0-2%). Stent migration occurred in 1% (95% CI: 0-3%). XEN45 revision and/or a second XEN45 implantation was performed in 5% of patients (95% CI: 3-7%). Stent relocation was performed in 3% (95% CI: 1-7%). A second glaucoma procedure was performed in 11% (95% CI: 8-15%). 26% underwent one (95% CI: 17-36%), 13% underwent two (95% CI: 5-24%) while 4% underwent three (95% CI: 2-6%) bleb needling procedures. 35% of patients (95% CI: 29-40%) required at least one needling. The average rate of needling per patient was 0.38 (95% CI: 0.20-0.59). However, there is a lack of high-quality data, with 8 of the 33 studies assessed to have a moderate to high risk of bias.

CONCLUSIONS

While literature suggests that XEN45 Gel Stent implantation is safe in the treatment of OAG, the overall current level of evidence is low and further studies are needed. More than a third of patients require at least one post-operative bleb needling procedure.

5-Fluorouracil in primary, impending recurrent and recurrent pterygium: Systematic review of the efficacy and safety of a surgical adjuvant and intralesional antimetabolite

Pterygium is an ultraviolet-related disease characterized by an aberrant, wing-shaped and active wound-healing process. There is nothing quite as disheartening for the surgeon or patient as the recurrence of pterygium, and various adjuvants have been studied to ameliorate this. This systematic review provides a comprehensive summary of the efficacy and safety of 5-Fluorouracil (5-FU) as an antimetabolite agent for pterygium management. An appraisal of electronic searches of six databases identified 34 clinical studies reporting recurrence outcomes of 5-FU use in primary, impending recurrent and recurrent pterygia. In vitro and in vivo studies of 5-FU showed dose- and duration-dependent cytostatic and cytotoxic effects in human cells. 5-FU is relatively inexpensive, available, and easy to administer, making it attractive for resource-limited scenarios. However, the published evidence demonstrates a recurrence rate of 11.4-60% with the bare scleral technique, 3.5-35.8% with conjunctival rotational flaps, 3.7-9.6% with conjunctival autografts for intraoperative topical 5-FU, and 14-35.8% for preoperative and intraoperative injections. This suboptimal efficacy brings the role of 5-FU as an adjuvant for pterygium surgery into question and the authors do not recommend its use. In contrast, postoperative intralesional injections of 5-FU to arrest progression in impending recurrent pterygium and true recurrent pterygia were more promising, with success rates of 87.2-100% and 75-100%, respectively. Furthermore, 5-FU as a treatment modality, without surgery, effectively arrested progression in 81.3-96% of primary and recurrent pterygia. Other treatments such as topical and intralesional corticosteroids, cyclosporine and anti-VEGF agents are discussed. Complications of 5-FU increase with higher doses and range from transient and reversible to severe and sight-threatening. For pterygium, 5-FU has a predilection for causing scleral thinning, corneal toxicity, and graft-related complications. Additional study with extended follow-up is needed to elucidate the optimal dose, frequency, duration, and long-term safety of 5-FU injections. If 5-FU is used in the management of pterygium, it should be with caution, in selected patients and with vigilant long-term monitoring.

Comparison of Outcomes Following Glaucoma Drainage Tube Surgery Between Primary and Secondary Glaucomas, and Between Phakic and Pseudophakic eyes

PURPOSE

To report outcomes of glaucoma drainage device (GDD) surgery based on primary or secondary glaucoma diagnosis and lens status.

DESIGN

Single-center, retrospective, consecutive cohort study.

METHODS

University of Florida patients aged 18 to 93 years who underwent nonvalved GDD surgery between 1996 and 2015 with a minimum of 1-year follow-up were examined. Of the 186 eyes of 186 patients enrolled, 108 had a primary glaucoma and 78 a secondary glaucoma diagnosis. Excluding 13 aphakic patients, 57 eyes were phakic and 116 pseudophakic. Mean intraocular pressure (IOP), mean number of medications, visual acuity (VA), surgical complications, and failure (IOP ≥18 mm Hg, IOP <6 mm Hg, reoperation for glaucoma, or loss of light perception) were the main outcome measures.

RESULTS

No significant difference was noted in mean IOP and mean medication use (12.8 ± 4.5 and 13.0 ± 6.6 mm Hg on 2.0 ± 1.2 and 1.5 ± 1.1 medication classes, respectively), mean VA (1.08 ± 0.98 and 0.94 ± 0.89, respectively), failure, or numbers of complications and reoperations (P > 0.05) between eyes with primary and secondary glaucomas at up to 5 years postoperatively. Comparison of phakic and pseudophakic eyes showed a statistically significant higher success rate for the pseudophakic patient group at the ≥18 mm Hg upper limit and <6 mm Hg lower limit (P = 0.01), and significantly fewer eyes required reoperation to lower IOP (6.9% vs 23%).

CONCLUSIONS

GDD surgery appears equally effective for secondary glaucomas as for primary glaucomas, and has a better outcome for pseudophakic eyes than phakic eyes.

Factors affecting the early and mid-term success of needling for early failure of filtering bleb

Purpose:

The purpose of this study is to evaluate the factors affecting the success of needling surgery for early filtering bleb failure after trabeculectomy.

Methods:

Patients who underwent a single needling surgery within 3 months after trabeculectomy were retrospectively evaluated. Glaucoma type, intraocular pressure (IOP), and medical treatments before trabeculectomy; the presence of hypotony after trabeculectomy; bleb type; IOP before needling; lens status; complications; IOP after 1, 6, and 12 months; and medical treatments after needling were recorded. Risk factors were evaluated for complete success at 1, 6, and 12 months after needling.

Results:

Thirty-three eyes of 33 patients were analyzed. The mean IOP after needling at 1, 6, and 12 months was 16.09 ± 3.70, 15.64 ± 2.68, and 15.79 ± 2.61 mmHg, respectively. The mean age of the patients was 53.97 (25–79) years. The mean IOP after needling at 1, 6, and 12 months was 16.09 ± 3.70, 15.64 ± 2.68, and 15.79 ± 2.61 mmHg, respectively. The pre-needling IOP and IOP decrease on the first day affected the complete and qualified success at 1, 6, and 12 months, but the glaucoma type, presence of hypotony after trabeculectomy, lens status, interval between trabeculectomy and needling, and bleb type were not found to affect success. In the receiver operating curve analysis, the pre-needling IOP value was found to be significant in determining complete success. Complete success at 1 month was more likely when the pre-needling IOP cutoff value was <24.5 mmHg.

Conclusion:

According to the results of single needling surgery performed within 3 months after trabeculectomy, the pre-needling IOP and IOP decrease with needling were found to be factors affecting success. Regardless of the time between the primary trabeculectomy and needling, effective needling will be successful before the IOP rises to high levels. Keeping the IOP at low values with medical treatment until the needling process is performed will have a positive effect on success.

History, presence, and future of mitomycin C in glaucoma filtration surgery

PURPOSE OF REVIEW

Mitomycin C (MMC) is an alkylating agent with extraordinary ability to crosslink DNA, preventing DNA synthesis. By this virtue, MMC is an important antitumor drug. In addition, MMC has become the gold standard medication for glaucoma filtration surgery (GFS). This eye surgery creates a passage for drainage of aqueous humor (AqH) out of the eye into the sub-Tenon's space with the aim of lowering the intraocular pressure. A major cause of failure of this operation is fibrosis and scarring in the sub-Tenon's space, which will restrict AqH outflow. Intraoperative application of MMC during GFS has increased GFS success rate, presumably mainly by reducing fibrosis after GFS. However, still 10% of glaucoma surgeries fail within the first year.

RECENT FINDINGS

In this review, we evaluate risks and benefits of MMC as an adjuvant for GFS. In addition, we discuss possible improvements of its use by adjusting dose and method of administration.

SUMMARY

One way of improving GFS outcome is to prolong MMC delivery by using a drug delivery system.

Safety and Efficacy of Bleb Needling with Antimetabolite after Trabeculectomy Failure in Glaucoma Patients: A Systemic Review and Meta-Analysis

Background

Bleb needling with subconjunctival injection of antimetabolites had become a widely accepted approach for trabeculectomy failure. However, IOP reduction effects, success rates, and complications occurrence for this procedure showed great inconsistency among the different studies.

Methods

We conducted a literature search on PubMed, Embase, Cochrane Library, and ClinicalTrials.gov. A random-effects model was performed on the extracted data based on the included studies. The intraocular pressure (IOP) and number of antiglaucomatous medications before and after the surgery were pooled for meta-analysis. The success and complication rates were estimated based on the results. Subgroup analysis, sensitivity analysis, and metaregression were applied to explore the origination of heterogeneity.

Results

Thirty-seven studies with a total of 2182 patients were finally included in our review. For the present meta-analysis, the overall effects of bleb needling at the last visit revealed a reduction in IOP of 9.74 mmHg (95% confidence interval (CI) [8.85, 10.63]), 45.9% (95% CI [39.0%, 53.0%]) for complete success rate, and 70.4% (95% CI [63.5%, 77.0%]) for qualified success rate. Application of mitomycin C (MMC) and 5-fluorouracil (5-Fu) during the procedure were efficacious for IOP control during the follow-up. Metaregression revealed that possible origination of heterogeneity was baseline IOP before bleb needling, revealing a trend that higher baseline IOP correlated with a greater IOP reduction results (p < 0.001). For safety profile, conjunctival haemorrhage (5.7%, 95% CI [2.5%, 10.1%]), hyphema (5.5%, 95% CI [3.0%, 8.7%]), and bleb leakage (5.0%, 95% CI [3.2%, 7.3%]) had the highest estimate of incidence. An increasing number of needling was the main risk factor for needling failure.

Conclusion

Bleb needling with antimetabolites could be considered an effective and safe procedure after trabeculectomy failure. After the process, patients will gain IOP control and reduce antiglaucomatous medications for at least six months with 5-Fu or MMC. Meanwhile, the overall estimates for complications were relatively low in the whole process.

Needling after XEN gel implant: What's the efficacy? A 1-year analysis

PURPOSE

To analyse the long-term efficacy and safety of bleb needling in glaucoma patients previously submitted to XEN implantation.

METHODS

Retrospective, observational study. Charts from patients who underwent XEN gel implant surgery between October 2015 and December 2017 were reviewed. Needling protocol involves use of Mitomycin C 0.2 mg/mL in an operating room. Primary outcome was defined as intraocular pressure (IOP) lowering efficacy at 12 months post-operative. Complete success was defined as a decrease in IOP > 20% and overall value <18 mmHg. Secondary outcomes included safety parameters (both intra and post-operative). Exploratory analysis of predictive factors for success were performed. Statistical analysis was performed using SPSS version 24.

RESULTS

About 94 charts were reviewed, with 18 patients (19%) having undergone needle revision. This salvage procedure was performed after 3.3 ± 3.4 months, achieving a mean IOP reduction of 8.3 ± 8.4 mmHg at 12 months after the procedure (pre-needling: 24.0 ± 5.2 mmHg vs 12th month: 13.5 ± 5.9 mmHg, p < 0.0001). Accordingly, success was achieved in 72% (complete success in 61% of cases). Among predictive factors, there was a higher tendency for success in patients on two types of medications or fewer pre-operatively, cases of standalone XEN surgery and patients with a higher IOP difference pre-needling - day 1. No vision-threatening complications were recorded.

CONCLUSION

XEN salvage procedure with mitomycin C is a valid option in early bleb failure. This single intervention had a long-lasting effect on bleb survival, with almost two-thirds achieving long term significant drop-free IOP reduction.

Needling after trabeculectomy - does augmentation by anti-metabolites provide better outcomes and is Mitomycin C better than 5-Fluoruracil? A systematic review with network meta-analyses

PURPOSE

Favourable outcome after glaucoma surgery depends on proper control of the inflammatory response. Failing filtration bleb and consequently increased intraocular pressure is an important cause of continuous visual field deterioration after uncomplicated glaucoma surgery. The present systematic review and meta-analysis aimed to compare the effects of employing either Mitomycin C (MMC), 5-Fluoruracil (5-FU) or no anti-metabolite in needling revision of trabeculectomies.

METHODS

We performed a systematic literature search in PubMed, Cochrane and EMBASE to identify randomized and non-randomized trials published between year 2000 and March 2019 comparing the efficacy of needling filtering blebs when using no anti-fibrotic agent, MMC or 5-FU in patients with glaucoma. Efficacy was defined as intraocular pressure at 12 months or latest follow-up, rate of complications, rates of success and the number of re-needling cases. Comparisons were made using network meta-analyses.

RESULTS

We identified one randomized trial and five retrospective trials. Twelve months after needling revision of trabeculectomy, no significant difference was observed when comparing the effect of the use of MMC with 5-FU or without any use of anti-metabolite on intraocular pressure, complication rates, qualified success, complete success or number of re-needling cases.

CONCLUSION

We found no significant difference in the efficacy of using either MMC, 5-FU or no anti-metabolite in needling revision of trabeculectomies. The number of studies meeting our inclusion criteria was limited. Considering the design of studies, only one was randomized leading to an overall low quality of evidence on the subject matter. Further research is warranted.

Measures to prevent the risks associated with exposure to cytostatic drugs in glaucoma filtering surgery

INTRODUCTION

The use of cytostatic drugs such as Mitomycin C and 5-Fluorouracil is well-known in glaucoma filtering surgery, as well as the management of its complications. However, there is a lack of information regarding the preventive measures to be taken by the professional that handles these types of substances.

OBJECTIVE

Raise awareness among professionals of the risks associated with the use of cytostatic drugs without adequate prevention measures.

RESULTS

Review of the available literature and legislation on preventive measures in the management of cytostatic drugs in the medical and ophthalmological field.

CONCLUSIONS

The prevention and awareness of the risks of the qualified professionals that handle these substances is the most important measure to prevent the possible risks. Coordination is necessary with the Occupational Health teams of the Hospital, as well as the professionals and staff involved in the different phases of the process, from the preparation in Hospital Pharmacy to its elimination.

Comparison of Efficacy and Safety of Bleb Needle Revision With and Without 5-Fluorouracil for Failing Trabeculectomy Bleb

PRéCIS:: Bleb needle revision with and without 5-FU showed similar success rates over the course of a long-term follow-up. A greater total number of needle revisions was identified as a risk factor for procedural failure.

PURPOSE

The purpose of the study was to investigate the efficacy and safety of bleb needle revision with adjunctive 5-fluorouracil (5-FU) subconjunctival injection in large-scaled patients with failing trabeculectomy bleb.

MATERIALS AND METHODS

A retrospective chart review was performed on a total of 113 eyes of 106 subjects who had undergone trabeculectomy followed by needle revision and been followed up for at least 6 months. The subjects were divided into 2 groups according to whether they had also undergone concurrent adjunctive 5-FU subconjunctival injection. Two definitions of failure were derived irrespective of IOP-lowering medication use and were assessed at each follow-up visit: (1) IOP>21 mm Hg or >85% of preoperative IOP or reoperation for glaucoma, (2) IOP>18 mm Hg or >80% of preoperative IOP or reoperation for glaucoma.

RESULTS

A total of 78 eyes of 73 subjects underwent the simple needle revision procedure and 35 eyes of 33 subjects underwent needle revision with subconjunctival 5-FU injection. There was no significant adverse event for either group and no significant IOP difference in any of the observational periods between them (P=0.867). There was also no statistically significant difference in the total number of IOP-lowering medications between the groups (P=0.199). The success rate at 24 months after the first needle revision was 45.6% (95% CI: 33.7, 56.7) in simple revision group and 44.6% (95% CI: 27.7, 60.2) in 5-FU needle revision group by failure 1, 36.3% (95% CI: 25.4, 47.2) and 32.9% (95% CI: 18.0, 48.6) by failure 2, respectively. A greater total number of needle revisions was the significant risk factors for needle revision failure (HR=2.25 and P=0.001 according to failure 2).

CONCLUSIONS

Bleb needle revision with 5-FU subconjunctival injection is a safe procedure for failing trabeculectomy bleb. Bleb needle revision with and without 5-FU were equally likely to succeed.

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.

Effects of rosiglitazone/PHBV drug delivery system on postoperative fibrosis in rabbit glaucoma filtration surgery model

The aim of this study is to investigate the effects and toxicities of poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV)-loading rosiglitazone on preventing scar formation after glaucoma filtration surgery (GFS) in the rabbit model. Rosiglitazone/PHBV drug delivery system was prepared via electrospinning. Release behavior of RSG/PHBV membrane was evaluated by high-performance liquid chromatography. The different concentration membranes were implanted under the conjunctiva of the rabbit’s eyes (RSG/PHBV groups). Also, MMC-soaked sponges were placed under the conjunctiva of the eyes (positive group) for 3 min. Intraocular pressures and bleb features were then assessed for 4 weeks postoperative. Bleb sections were stained with HE, Masson’s trichrome and α smooth muscle action (αSMA) immunohistochemistry. The protein expression of collagen I, αSMA, and connective tissue growth factor in the bleb area were then quantified. The following results were observed: (1) the concentration of rosiglitazone would not affect the morphology of RSG/PHBV membrane. (2) RSG/PHBV membrane would effective and safety prevent the formation of fibrosis after GFS in the rabbit model. Implantation of RSG/PHBV membrane prevents scar formation after GFS. What’s more, it ameliorated toxicity to conjunctiva and cornea compared with the placement of MMC. The RSG/PHBV membrane would be a more effectivity and safer strategy than MMC.

Needling With 5-Fluorouracil (5-FU) After XEN Gel Stent Implantation: 6-Month Outcomes

PURPOSE

The purpose of this study was to evaluate frequency, safety, and efficacy of needling in patients that underwent XEN Gel Stent implantation.

METHODS

Retrospective case review of 19 eyes of 57 consecutive patients (61 eyes) with primary open-angle glaucoma or pseudoexfoliative glaucoma that previously underwent implantation of XEN45 alone or in combination with cataract surgery followed by needling procedure with 5-FU. Success was defined at 2 IOP levels: ≤21 mm Hg and ≤15 mm Hg, with or without additional glaucoma medications. Treatment failure was defined as IOP>21 mm Hg or <5 mm Hg, need for additional glaucoma surgery or loss of light perception.

RESULTS

Totally 19 of 61 eyes that underwent XEN gel implantation had subsequent needling and were included. Preneedling IOP was 26.2±9.5 and postneedling IOP at last follow-up 15.4±3.7 mm Hg (P=0.0001). Overall success rates of 17 (90%) and 13 eyes (69%) were observed at the ≤21 mm Hg and ≤15 mm Hg level, respectively. Preneedling and postneedling visual acuity and number of medications remained unchanged (P>0.05). Two eyes (10%) were categorized as treatment failures. No major complications occurred. Mean follow-up was 203.8±142.2 (range, 22 to 456) days.

CONCLUSIONS

Needling revision following XEN gel stent implantation showed a good IOP-lowering effect without significant increase in number of antiglaucoma medications, decrease in visual acuity, nor any major complications. Further studies with long-term follow-up and a larger number of patients are needed to fully assess the safety and efficacy of this procedure.

Outcomes of Wider Area Bleb Revision Using Bleb Knife With Adjunctive Mitomycin C

PRECIS

Wider area bleb revision using bleb knife with adjunctive mitomycin C (MMC) had a good success rate, according to strict success criteria, except in patients with neovascular glaucoma (NVG).

PURPOSE

We determined the efficacy of wider area bleb revision after filtering surgery using bleb knife with adjunctive MMC.

PATIENTS AND METHODS

In this retrospective single-center study, we analyzed 86 patients with glaucoma (46 primary open-angle, 18 exfoliations, 13 secondary, and 9 neovascular) after bleb revision using bleb knife with adjunctive MMC after a minimum follow-up of 6 months. A Kaplan-Meier survival analysis with log-rank tests and Cox proportional hazards regression analyses were performed. The main outcome measure was a successful initial bleb revision using bleb knife with adjunctive MMC, arbitrarily defined as intraocular pressure (IOP) control <15 mm Hg without any IOP-lowering medication, additional bleb revision, or glaucoma surgery.

RESULTS

The mean time since the initial filtering surgery was 243.8 days, and the mean prebleb revision IOP was 22.0±4.8 mm Hg. The total cumulative success rate of the bleb revision using bleb knife with MMC was 49% at 6 months and 30% at 1 year. Patients with primary open-angle glaucoma had the best success rate (64% at 6 mo and 40% at 1 y). Log-rank tests revealed that patients with NVG had the worst prognosis (P<0.01). NVG was the only significant risk factor identified for short survival time (odds ratio, 167.10; 95% confidence interval, 1.78-15620.44; P=0.027).

CONCLUSION

Wider area bleb revision using bleb knife with adjunctive MMC had a good success rate, according to strict success criteria, except in patients with NVG.

Recommendations for the management of elevated intraocular pressure due to bleb fibrosis after XEN gel stent implantation

Surgical management of glaucoma offers a means of effective disease control. A gel stent that facilitates drainage to the subconjunctival space offers intraocular pressure (IOP) reduction similar to traditional glaucoma filtering surgeries in a less invasive manner. However, like all subconjunctival filtering procedures that result in a bleb, fibrosis can present as a cause of elevated IOP. The following proposed techniques and recommendations for managing elevated IOP due to bleb fibrosis after gel stent implantation are based on the clinical experience of the authors. The goal of this paper is to improve outcomes following gel stent surgery by providing guidance on assessment of bleb function and strategies for bleb enhancement.

Needle revision outcomes after glaucoma filtering surgery: survival analysis and predictive factors

Purpose:

To evaluate the efficacy and safety of needle revision and examine factors predictive of failure.

Methods:

In total, 157 eyes of 131 patients that underwent needle revision augmented with either 5-fluorouracil or betamethasone for trabeculectomy failure were included in this retrospective study. Complete failure was defined as additional glaucoma surgery, ciliodestructive procedures, loss of light perception, sight-threatening complications, hypotony maculopathy, and surgical bleb revision. Success was defined as intraocular pressure ⩽ 18 (criterion A), ⩽15 (criterion B), and ⩽12 mmHg (criterion C) reached with (qualified) or without (complete) medications, and absence of any criteria of complete failure.

Results:

The median (interquartile range) follow-up was 25.0 (41.0) months. Complete failure rates were 19%, 26%, and 31% at 1, 2, and 3 years, respectively. For criterion A, qualified and complete success rates were, respectively, 77% and 69% at 1 year, 66% and 51% at 2 years, and 60% and 47% at 3 years. For criterion B, qualified and complete success rates were, respectively, 67% and 61% at 1 year, 48% and 42% at 2 years, and 44% and 39% at 3 years. For criterion C, qualified and complete success rates were, respectively, 43% and 41% at 1 year, 27% and 25% at 2 years, and 24% and 23% at 3 years. High baseline intraocular pressure and primary surgery were associated with higher and lower risks of complete failure, respectively.

Conclusion:

Needle revision is an effective and safe procedure to rescue failing trabeculectomy postponing or avoiding further glaucoma surgery. Eyes with low target intraocular pressure may have poor long-term outcomes.

Smaller-incision Revision of Trabeculectomy With Mitomycin: Long-term Outcomes and Complications

PURPOSE

The purpose of this study was to assess long-term outcomes and complications of smaller-incision trabeculectomy revision with mitomycin (MMC) in glaucoma patients.

METHODS

Review of patients undergoing trabeculectomy revision with MMC for inadequate intraocular pressure (IOP) control. After dissection of subconjunctival fibrosis through a smaller (median, 5 mm) incision, MMC was topically applied and episcleral fibrosis was incised. Failure was defined as reoperation for glaucoma, or IOP reduction < 20% over 3 follow up visits.

RESULTS

Forty eyes (40 patients; mean age, 67±13 y) underwent revision; 9 revisions were combined with other surgery. Mean baseline IOP was 20.6±6.2 mm Hg on 2.6±1.4 glaucoma medications after 2.4±1.3 incisional ocular surgeries. At final follow-up (70±34 mo), 27 successful eyes (67.5%) had IOP of 9.2±2.4 mm Hg on 0.6±0.9 medications. Eleven eyes (27.5%) required reoperation for glaucoma, 7 (63%) within 7 months after revision. The Kaplan-Meier estimate of success at years 1, 2, 3, and 5 postoperatively was 77.5%, 72.2%, 69.5%, and 69.5%, respectively. Recovery of visual acuity to within 2 lines of baseline was 1.7±2.4 weeks (median 1). Complications included sustained hypotony (IOP, ≤5 mm Hg) in 2 eyes (1 also with corneal decompensation), 1 eye with wound leak, and 2 eyes with bleb leak (1 requiring surgical repair).

CONCLUSIONS

Smaller-incision trabeculectomy revision with MMC resulted in substantial, sustained IOP reduction in most eyes with poorly functioning filtering blebs, with few serious complications and rapid recovery of baseline visual acuity in most eyes.

Long-term outcome of mitomycin C-augmented needle revision of trabeculectomy blebs for late trabeculectomy failure

OBJECTIVES

To describe the 3-year outcomes of mitomycin C (MMC)-augmented bleb needling procedures following late trabeculectomy failure.

METHODS

A retrospective, observational chart review of 44 eyes that underwent MMC-augmented bleb needling following late trabeculectomy failure. The primary outcome measure was IOP at 3 years post-operatively. Secondary outcome measures were the number of topical glaucoma medications and success rate at 3 years. Success was defined on the basis of IOP (≤21 mmHg and ≥5 mmHg with a reduction of ≥ 20% from pre-operative baseline), need for ocular hypotensive medications, and need for further laser or surgical intervention.

RESULTS

Mean IOP was reduced from 19.8 mmHg preoperatively to 13.9 mmHg (29.5% reduction) at 3 years. By the 3-year time point, 26 eyes (59.1%) had met one or more of the criteria for failure. A lower immediate post-operative IOP was found to be associated with greater likelihood of success.

CONCLUSIONS

Bleb needling augmented with MMC can achieve a significant reduction in IOP in eyes with late trabeculectomy failure. By 3 years however, 59% of eyes were classified as failures, with half requiring further glaucoma surgery or laser. Patients undergoing this procedure should therefore be warned of the likelihood of requiring further intervention, and a repeat antimetabolite-augmented trabeculectomy or glaucoma tube shunt surgery in the first instance can be considered instead.

Rescue of failing or failed trabeculectomy blebs with slit-lamp needling and adjunctive mitomycin C in Indian eyes

Purpose:

The aim of this study is to investigate the efficacy and safety of needling-revision augmented with a high dose of mitomycin C (MMC) in failing or failed blebs after trabeculectomy in Indian eyes.

Methods:

Prospective, noncomparative, interventional study. All patients (>18 years) who had raised intraocular pressure (IOP) following trabeculectomy (>6 weeks and <2 years), who had a flat bleb, bleb encapsulation, and/or required antiglaucoma medication (AGM) for IOP control were eligible for inclusion. MMC was injected subconjunctivally at least ½ hour before the needling procedure was carried out at the slit lamp in the outpatient's clinic.

Results:

Thirty-nine eyes of 38 patients were included. The median follow-up was 20 months and time interval between trabeculectomy and needle revision was 113 days. Initially, in all cases, aqueous flow was re-established with a raised bleb; 7 eyes required repeat needling. IOP decreased from median 24 mmHg (Q1 21, Q3 27, interquartile range [IQR] 6, range 18–35) preneedling to median 14 mmHg (Q1 10, Q3 16, IQR 6, range 6–18) postneedling at last follow-up (P < 0.0001, 95% confidence interval [CI]: 8.2–13.0). The use of AGM reduced from median 1 (Q1 0, Q3 3, IQR 3, range 0–4) preneedling to median 0 postneedling (P < 0.0001, 95% CI: 1–2). Complete success was seen in 28 eyes (71.8%, 95% CI: 71.1%–96.4%); another 5 eyes (12.8%) were controlled with AGM (qualified success) with overall success of 84.6%. Most complications were transient in nature with resolution within 1 week. One patient developed hypotony, and another developed a late bleb leak.

Conclusion:

Needling revision augmented with high-dose MMC, at the slit lamp, effectively rescues failing or failed filtration, and appears to be safe.

Predictive value of early postoperative IOP and bleb morphology in Mitomycin-C augmented trabeculectomy

Background: To determine the predictive value of postoperative bleb morphological features and intraocular pressure (IOP) on the success rate of trabeculectomy.

Methods: In this prospective interventional case series, we analyzed for one year 80 consecutive primary open angle glaucoma patients who underwent mitomycin-augmented trabeculectomy. Bleb morphology was scored using the Indiana bleb appearance grading scale (IBAGS). Success was defined as IOP ≤15 mmHg at 12 months. We applied a multivariable regression analysis and determined the area under the receiver operating characteristic curve (AUC).

Results: The mean age of participants was 62±12.3 years in the success and 63.2±16.3 years in the failure group (P= 0.430) with equal gender distribution (P=0.911). IOPs on day 1, 7 and 30 were similar in both (P= 0.193, 0.639, and 0.238, respectively.) The AUC of IOP at day 1, day 7 and 30 for predicting a successful outcome was 0.355, 0.452, and 0.80, respectively. The AUC for bleb morphology parameters of bleb height, extension, and vascularization, on day 14 were 0.368, 0.408, and 0.549, respectively. Values for day 30 were 0.428, 0.563, and 0.654. IOP change from day 1 to day 30 was a good predictor of failure (AUC=0.838, 95% CI: 0.704 to 0.971) with a change of more than 3 mmHg predicting failure with a sensitivity of 82.5% (95% CI: 68 to 91%) and a specificity of 87.5% (95% CI: 53 to 98%).

Conclusions: IOP on day 30 had a fair to good accuracy while bleb features failed to predict success except bleb vascularity that had a poor to fair accuracy.  An IOP increase more than 3 mmHg during the first 30 days was a good predictor of failure.

Predictive value of early postoperative IOP and bleb morphology in Mitomycin-C augmented trabeculectomy

Background: To determine the predictive value of postoperative bleb morphological features and intraocular pressure (IOP) on the success rate of trabeculectomy. Methods: In this prospective interventional case series, we analyzed for one year 80 consecutive primary open angle glaucoma patients who underwent mitomycin-augmented trabeculectomy. Bleb morphology was scored using the Indiana bleb appearance grading scale (IBAGS). Success was defined as IOP ≤15 mmHg at 12 months. We applied a multivariable regression analysis and determined the area under the receiver operating characteristic curve (AUC). Results: The mean age of participants was 62±12.3 years in the success and 63.2±16.3 years in the failure group (P= 0.430) with equal gender distribution (P=0.911). IOPs on day 1, 7 and 30 were similar in both (P= 0.193, 0.639, and 0.238, respectively.) The AUC of IOP at day 1, day 7 and 30 for predicting a successful outcome was 0.355, 0.452, and 0.80, respectively. The AUC for bleb morphology parameters of bleb height, extension, and vascularization, on day 14 were 0.368, 0.408, and 0.549, respectively. Values for day 30 were 0.428, 0.563, and 0.654. IOP change from day 1 to day 30 was a good predictor of failure (AUC=0.838, 95% CI: 0.704 to 0.971) with a change of more than 3 mmHg predicting failure with a sensitivity of 82.5% (95% CI: 68 to 91%) and a specificity of 87.5% (95% CI: 53 to 98%). Conclusions: IOP on day 30 had a fair to good accuracy while bleb features failed to predict success except bleb vascularity that had a poor to fair accuracy.  An IOP increase more than 3 mmHg during the first 30 days was a good predictor of failure.

Ab Interno Trabeculectomy With the Trabectome as a Valuable Therapeutic Option for Failed Filtering Blebs

PURPOSE

Uncontrolled intraocular pressure (IOP) after glaucoma filtration surgery is a challenging problem in the management of glaucoma patients. The Trabectome is a device for selective electroablation of the trabecular meshwork through a clear cornea incision without affecting the conjunctiva. Minimally invasive glaucoma surgery using the Trabectome is safe and effective as primary glaucoma surgery. Here we investigate the results of ab interno trabeculectomy with the Trabectome for IOP control in patients with a failed filtering bleb.

METHODS

A total of 60 eyes of 60 consecutive patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PXG) were enrolled in this single center observational study. Trabectome surgery was performed alone or in combination with phacoemulsification by 2 experienced surgeons. IOP readings and number of IOP lowering medication as primary outcome parameters were taken by an independent examiner. Intraoperative and postoperative medication were recorded systematically.

RESULTS

Mean IOP before surgery was 24.5±3.5 mm Hg and decreased to 15.7±3.4 (-36%) after mean follow-up of 415 days. The number of necessary IOP lowering medication dropped from 2.1±1.3 to 1.8±1.2 (14% reduction from baseline). A total of 25% (n=15) of cases reported here needed additional surgery after 517 days (range: 6 to 1563 d). No major complications were observed. After mean follow-up, we found a qualified success rate for PXG of 87% and 50% for POAG as revealed by the Kaplan-Meier analysis according to the definitions for success in advanced glaucoma cases according to the World Glaucoma Association (40% reduction from baseline IOP and maximum IOP of 15 mm Hg).

DISCUSSION

Trabectome surgery for uncontrolled IOP after trabeculectomy is safe and effective especially in PXG patients. Given the demanding subgroup of patients studied here, it is not surprising that success rates are lower compared with previous studies investigating the Trabectome for primary glaucoma surgery. The number of necessary IOP lowering medication drops at first, but seems to reach preoperative values after 20 months of follow-up. Trabectome surgery should be considered as a valuable escape procedure for patients with failed filtering blebs and uncontrolled IOP.

Same-site surgical revision of failed trabeculectomy blebs with mitomycin C augmentation: long-term follow-up

PurposeTo determine the long-term outcomes of same-site revision of failed filtering blebs with mitomycin C application.Patients and methodsNoncomparative retrospective case series of 45 eyes of 39 patients. Main outcome measures were surgical success (≤21, ≤18, and ≤16 mm Hg reduction in intraocular pressure (IOP)). Other outcome measures included best-corrected visual acuity (VA), visual field loss, number of glaucoma medications, need for further interventions, time from surgery to recommencement of medications or interventions, and complications.ResultsMean follow-up was 126±59.6 months (range 16-227 months). The overall success proportion at last follow-up was 96% for IOP ≤21 mm Hg (criterion 1), 91% for IOP ≤18 mm Hg (criterion 2), and 84% for IOP ≤16 mm Hg (criterion 3). Absolute success at last follow-up was 64%, 38%, and 33% for criteria 1, 2, and 3, respectively. Mean baseline IOP was reduced from 24.2±5.5 to 12.4±5.5 mm Hg at last follow-up. Ten eyes (22%) had early and 3 (7%) eyes had late complications. None of these complications resulted in visual loss or surgery failure. Nine eyes (20%) required further glaucoma surgery. Nine eyes (20%) required further glaucoma laser.ConclusionsSame-site, augmented, bleb revision is a safe and effective technique to control IOP and prevent further visual loss in patients with failed trabeculectomies.

Posterior Surgical Revision of Failed Fornix-based Trabeculectomy

PURPOSE

To evaluate outcomes after revision of failed fornix-based trabeculectomy using a posterior conjunctival incision and mitomycin C.

METHODS

Cases were identified using Current Procedural Terminology codes. Information from clinical records was analyzed retrospectively. Complete success was defined as intraocular pressure (IOP) ≤16 mm Hg with no glaucoma medications and IOP reduction of >20% from preoperative levels. Qualified success was defined as IOP≤16 with or without medications and IOP reduction of >20%. Secondary outcomes included IOP, number of glaucoma medications used, visual acuity, and complications.

RESULTS

Sixty eyes of 56 patients underwent surgical revision of failed trabeculectomy. The complete success rate at 1 year was 43.7%, declining to 41.7% at 2 years and all time points up to 5 years; qualified success rates were 68.9% at 1 year and at all subsequent time points. Mean IOP declined from 21.2±7.7 (SD) mm Hg preoperatively to 10.9±4.3 mm Hg at 1 year, to 10.5±3.8 mm Hg at 2 years, and to 9.9±4.6 mm Hg at 3 years. The mean number of glaucoma medications used fell from 2.5±0.5 preoperatively to 1.0±0.4 at 1 year, 0.9±0.4 at 2 years, and 0.9±0.4 at 3 years. Complications included bleb leak in 3 eyes (5.0%), hypotony with choroidal detachment in 3 eyes (5.0%) and hyphema in 1 eye (1.7%). Eight eyes required additional glaucoma surgery.

CONCLUSIONS

Surgical bleb revision with mitomycin C using a posterior incision in cases of failed fornix-based trabeculectomy can provide effective control of IOP. This conjunctiva-sparing procedure should be considered as a viable alternative to a tube shunt or repeat trabeculectomy.

Revision of trabeculectomy filtering blebs with mitomycin C: Long term results

Aim:

The aim of the study is to assess the outcomes of transconjunctival mitomycin C (MMC)-augmented revision in eyes with failed trabeculectomy.

Materials and Methods:

This is a retrospective, noncomparative case series. One hundred and twenty-one eyes of 113 consecutive glaucoma patients with previously failed trabeculectomy who underwent transconjunctival revision with at least 12 months of follow-up were initially included in the study. The success was determined on the basis of intraocular pressure (IOP) alone. The main outcome measures were IOP, best-corrected distance visual acuity, complications, bleb appearance, lens status, visual field progression, and time between primary trabeculectomy and MMC revision. The main purpose of the study was to determine the efficacy of a single MMC-augmented needle revision.

Results:

Mean follow-up was 2.3 years. Twelve months after revision, IOP had declined from 26.1 ± 8.4 mmHg to 14.1 ± 4.8 mmHg (P < 0.05) and remained 16.0 ± 5.6 mmHg at 24 months, 15.7 ± 5.8 mmHg at 48 months, and 15.2 ± 4.0 mmHg at 60 months. Complete success was achieved in 53% of cases, 84% achieved qualified success, and 16% were classified as failures 12 months after revision. Early complications developed in 45 of the initial 121 eyes (37.2%).

Conclusions:

Transconjunctival MMC-augmented revision appears to be a safe and useful tool in reducing IOP and re-establishing filtration after trabeculectomy failure. This simple procedure has a high rate of success and helps avoid other surgical interventions which are more destructive for the conjunctiva.

Revision of encapsulated blebs after trabeculectomy: Long-term comparison of standard bleb needling and modified needling procedure combined with transconjunctival scleral flap sutures

PURPOSE

To compare two surgical approaches for treating encapsulated blebs after trabeculectomy with mitomycin C, in terms of the development of intraocular pressure and progression of glaucoma in a long-term follow up: 1. bleb needling alone vs. 2. a combined approach of needling with additional transconjunctival scleral flap sutures, to prevent early ocular hypotony.

METHODS

Forty-six patients with failing blebs after trabeculectomy with mitomycin C were enrolled in this study. Patients received either needling revision alone (group 1; n = 23) or a combined needling with additional transconjuctival flap sutures, if intraoperatively the intraocular pressure was estimated to be low (group 2; n = 23). Intraocular pressure (IOP), visual acuity, visual fields, and optic nerve head configuration by means of Heidelberg Retina Tomograph (HRT®) were analysed over time. Results from both groups were compared using Mann-Whitney U-test for single timepoints.

RESULTS

IOP did not differ significantly between the two groups during follow-up at three months (P = 0.13), six months (P = 0.12), one year (P = 0.92) and two years (P = 0.57) after surgery. Furthermore, there was no significant difference in the course of glaucoma concerning the optic nerve anatomy between the two groups (Rim Area Change in the Moorfields Regression Analysis of HRT®) till two years after surgery (P = 0.289). No functional impairment in visual acuity and visual fields was found in the groups of the study.

CONCLUSIONS

Single needling procedure is a standard successful method for restoring the function of encapsulated blebs. Postoperative hypotony represents a possible hazard, which can be minimized by additional transconjunctival flap sutures. Long-term results suggest that this modification is equally effective in lowering the IOP and preventing the progression of glaucoma as the standard needling procedure. To our knowledge this is the first study to investigate the long-term effect of tranconjunctival sutures for the prevention of hypotony.

Outcomes of Bleb Revision With Mitomycin C After Ex-PRESS Shunt Surgery

PURPOSE

Investigate efficacy and safety of bleb revision using mitomycin C after Ex-PRESS shunt surgery.

PATIENTS AND METHODS

We performed chart reviews of 36 consecutive eyes from 34 patients with previous Ex-PRESS shunt surgery who underwent subsequent bleb revision with mitomycin C. The mean follow-up time was 13.5 months. The primary outcome measure was surgical success. Secondary outcomes included visual acuity, intraocular pressure, number of medications, and complications.

RESULTS

Twenty-four eyes had open-angle glaucoma (61.1%). Mean time from Ex-PRESS to bleb revision was 8.8 months. Complete success rate for the immediate 3-month postoperative period was 94.4% and qualified success rate was 97.2%. Complete and qualified success rates for the entire follow-up period were 40% and 65.7%, respectively. Visual acuity remained stable throughout the study period, and at 1 year, average intraocular pressure was 14.7 mm Hg on an average of 1.7 medications. No major complications were reported.

CONCLUSIONS

Bleb revision in eyes with an Ex-PRESS shunt is a safe and efficacious procedure. The surgical outcomes are within the range of published outcomes for bleb needling after trabeculectomy. Further research with larger sample size and longer follow-up is needed to confirm these results.

Results From a Modified Bleb Needling Procedure With Continuous Infusion Performed in the Operating Room

PURPOSE

Needling of a scarred trabeculectomy bleb is often performed in the office using a slit-lamp microscope as an alternative to additional surgery to lower intraocular pressure (IOP). However, the success rate in an office setting is highly variable, with reported success rates as low as 13%. We report a retrospective assessment of an intraoperative needling technique for reviving failed blebs.

DESIGN

A retrospective chart review.

PARTICIPANTS

Patients undergoing the intraoperative modified bleb revision technique in the setting of a failed trabeculectomy due to scarring at the Wilmer Eye Institute, Johns Hopkins Hospital between August 16, 2010 and August 29, 2012.

METHODS

Patients with uncontrolled IOP were operated on using a modified bleb needling technique. In this technique, a 25-G infusion cannula is placed in the anterior chamber and fibrotic adhesions within the bleb are lysed with a 25-G needle. The continuous infusion of balanced salt solution from the anterior chamber causes bleb elevation, which helps to guide the endpoint of lysis for the procedure. A subconjunctival injection of 5-fluorouracil is given at the conclusion of each case.

MAIN OUTCOME MEASURES

IOP reduction and number of glaucoma medications at postoperative day 1, week 1, month 1, month 3, month 6, and month 12.

RESULTS

A total of 33 eyes of 30 patients were included. At the visit before the procedure, the mean (±SD) IOP was 22.1±9.2 (range, 11 to 58) and subjects were using an average of 2.3±1.4 (range, 0 to 4) glaucoma medications. The mean IOP reduction was 8.7 mm Hg [95% confidence interval (CI), 5.6-11.8] at postoperative day 1, 8.1 mm Hg (95% CI, 4.0-12.3) at week 1, 8.9 mm Hg (95% CI, 5.3-12.5) at month 1, 8.1 mm Hg (95% CI, 4.2-12.0) at month 3, 8.2 mm Hg (95% CI, 3.9-12.5) at month 6, and 6.2 mm Hg (95% CI, 3.6-8.7) at month 12. IOP was reduced about 30% to 40% compared with baseline at each time point (P<0.05). The average reduction in medications used was 1.7 at day 1, 1.0 at month 1, 1.2 at month 3, 1.5 at month 6, and 0.5 at month 12. Seven patients underwent repeat needling. Overall, 64% of subjects maintained IOP at or below their target after 12 months.

CONCLUSIONS

A modified bleb needling procedure performed in the operating room can successfully lower IOP in the setting of a previous trabeculectomy in over 60% of subjects a year after the procedure.

Outcomes: Trabeculectomy Bleb Needle Revision With 5-Fluorouracil

PURPOSE

To evaluate outcomes of trabeculectomy bleb needle revision with 5-fluorouracil augmentation performed in the operating theater.

METHODS

Retrospective study of all patients undergoing trabeculectomy bleb needle revisions in the operating theater performed by a single surgeon in a metropolitan hospital in Australia. A total of 51 needle revisions were performed on 33 eyes over a mean follow-up time of 1.81±1.56 years.

RESULTS

A total of 29% achieved intraocular pressure (IOP) ≤20 mm Hg off all glaucoma medications, and an additional 39% achieved qualified success with the addition of glaucoma medications, giving overall success of 68%. Analyzing success rate for target IOP≤16 mm Hg, 24% achieved target off all glaucoma medications, 35% achieved qualified success with the addition of glaucoma medications, giving an overall success rate of 59%. There was a statistically significant improvement in IOP, as compared with preoperative levels, at all timepoints postoperatively (P<0.05). However, number of glaucoma medications remained unchanged (P>0.05) contributing to the high percentage of qualified successes. Visual acuity remained unchanged and there were no major postoperative complications. The Kaplan-Meier survival shows a survival rate of 60% with IOP≤20 mm Hg and 40% for IOP≤16 mm Hg at 5 years.

CONCLUSIONS

Trabeculectomy needle revision is a useful option for the management of elevated IOP in the presence of a failed or failing trabeculectomy bleb. However, as with trabeculectomy, there tends to be a failure rate over time. This often leads to reinstitution of glaucoma medications and/or further needle revisions to maintain IOPs at target level. The procedure itself is minimally invasive with an acceptable safety profile.

A New Method for Revision of Encapsulated Blebs after Trabeculectomy: Combination of Standard Bleb Needling with Transconjunctival Scleral Flap Sutures Prevents Early Postoperative Hypotony

Purpose

A simple needling procedure is the standard method for restoring the function of an encapsulated bleb after trabeculectomy. However, postoperative hypotony represents a possible hazard. This study describes a new surgical approach for treating encapsulated blebs with reduced risk of early postoperative hypotony: bleb needling combined with transconjunctival sutures tightening the scleral flap directly.

Methods

The study included two groups of 23 patients with failing bleb following trabeculectomy: “Group 1” underwent simple needling revision of the filtering bleb and served as a control group, while “Group 2” received needling revision with additional transconjunctival scleral flap sutures, if intraoperatively the intraocular pressure was estimated to be very low. Intraocular pressure (IOP), postoperative management and complications were analyzed over a follow-up period of 4 weeks postoperatively. Results were compared using t-test or Mann-Whitney U-tests.

Results

Adverse effects occurred with a higher frequency after sole needling of the bleb (5 cases of choroidal effusion and 1 case of choroidal hemorrhage) than after the combined method with additional scleral sutures (1 case of choroidal effusion). The IOP on the first postoperative day was significantly lower in group 1, with 9.43 ± 9.01 mm Hg vs. 16.43 ± 8.35 mm Hg in group 2 (P = 0.01). Ten patients with ocular hypotony (IOD of 5 mmHg or lower) were found in group 1 and only two in group 2. One week and one month after surgery the intraocular pressure was similar in both groups (P>0.05).

Conclusions

This new needling technique with additional transconjunctival scleral flap sutures appears to reduce postoperative hypotony, and may thus protect from further complications, such as subchoroidal hemorrhage.

Comparison of Subconjunctival Mitomycin C and 5-Fluorouracil Injection for Needle Revision of Early Failed Trabeculectomy Blebs

Background. To compare the efficacy of needle revision with 5-fluorouracil (5-FU) and mitomycin C (MMC) on dysfunctional filtration blebs shortly after trabeculectomy. Methods. It is a prospective randomized study comparing needle revision augmented with MMC or 5-FU for failed trabeculectomy blebs. Results. To date 71 patients (75 eyes) have been enrolled, 40 eyes in the MMC group and 35 in the 5-FU group. 68 patients (72 eyes) have completed 12-month follow-up, 38 eyes in the MMC group and 34 in the 5-FU group. The mean IOP before and that after needle revision in the MMC group were 26.5 ± 4.3 mmHg and 11.3 ± 3.4 mmHg, respectively (P < 0.05), and in the 5-FU group were 27.1 ± 3.8 mmHg and 10.9 ± 3.4 mmHg, respectively (P < 0.05). At 12-month follow-up, complete success rates were 57.5% for MMC group and 34.3% for 5-FU group (P = 0.042; log-rank test) and 75% and 60% (P = 0.145; log-rank test), respectively, for the qualified success. Complication rates between the two groups were not statistically different (P > 0.05). Conclusions. Needle revision and subconjunctival MMC injection were more effective than needling and subconjunctival 5-FU injection for early dysfunctional filtration blebs after trabeculectomies.

Prospective study comparing mitomycin C or bevacizumab as adjuvant in trabeculectomy revision by needling

PURPOSE

To compare the use of mitomycin C (MMC) or bevacizumab (BEV) as adjunctive in the needling revision of failed trabeculectomy blebs.

METHODS

Glaucoma patients with failed trabeculectomy were included. Cystic blebs were excluded. All procedures were performed by the same surgeon at the operating room under peribulbar blockade. Rate of success, intraocular pressure (IOP), and number of antiglaucoma drugs in use were compared before and after the procedures. The IOP was measured postoperatively at days 1, 30, 90, and 180. Absolute success was defined as IOP ≤18 mm Hg, without any complication or use of any antiglaucomatous drugs. Qualified success was the same criteria, but with the use of any antiglaucomatous drugs.

RESULTS

Twenty-nine eyes of 29 patients were included: 15 eyes with MMC and 14 eyes with BEV. There was no statistical difference in the IOP reduction between the groups (MMC 32.6 ± 16.1% vs BEV 30.1 ± 12.0%, p = 0.6). The BEV group showed similar reduction in the number of antiglaucoma drugs compared to the MMC group (p = 0.6). Absolute success was found in 28.5% of the BEV group and in 6.6% of patients with MMC. Qualified success was found in 64.3% and 73.4%, respectively, both limited to 180 days.

CONCLUSIONS

In this selected and limited group of patients, bevacizumab can be considered as an alternative to MMC in the needling revision of failed trabeculectomy. Studies with a larger number of patients and longer follow-up are needed to confirm the hypothesis suggested here.

Bleb needling outcomes for failed trabeculectomy blebs in Asian eyes: a 2-year follow up

AIM

To describe the outcomes of bleb needling in primary glaucoma in an Asian tertiary eye centre over a 2y period. To compare the success rates between primary angle-closure glaucoma (PACG) and primary open angle glaucoma (POAG). Lastly, to identify factors associated with success of bleb needling.

METHODS

This was a retrospective review of 227 patients who underwent bleb needling between June 2009 and June 2011 in Singapore National Eye Centre. The 5-fluorouracil (5-FU) augmented bleb needling was performed either at the slit lamp or in the operating theatre. Repeat bleb needlings were performed as necessary. Complete success was defined as maintenance of intraocular pressure (IOP) ≥6 mm Hg and ≤21 mm Hg, in the absence of further surgery or use of antiglaucoma medication. Qualified success met the above criteria with or without use of antiglaucoma medications.

RESULTS

One hundred and seventy-five eyes completed the two-year follow up. Sixty-nine percent of participants had POAG and 31% had PACG. The mean interval between filtering surgery and bleb needling was 299.9±616.4d for POAG and 167.1±272.2d for PACG. Mean needling attempts were 1.9±1.4 and 2±1.6 for POAG and PACG respectively. In general, there was a statistically significant reduction of IOP ranging from 21.9% to 26.8% from month 1 through to month 24. The complete success rates at month 6 were 70.0% for POAG and 65.7% for PACG. At month 12, this decreased to 62.2% for POAG and PACG and at month 24, 57.9% for POAG and 63.0% for PACG respectively. The qualified success rates at month 6 for POAG and PACG were 23.8% and 29.9% respectively, 32.2% and 29.2% at month 12, and 34.7% and 29.6% at month 24. The success rates between POAG and PACG were not significantly different (P>0.05 for complete and qualified success at months 6, 12 and 24). An increased number of needlings and higher pre-needling IOP were associated with failure.

CONCLUSION

The 5-FU augmented bleb needling within one year of trabeculectomy in Asian eyes can provide clinically significant IOP lowering of more than 20% for 2y. POAG and PACG had similar complete success rates (58% and 63% respectively). Factors associated with greater risk of procedure failure included increased number of needlings and higher pre-needling IOP. Asian eyes have a greater propensity for scarring but bleb needling, if performed in a timely manner can rescue bleb function.

Time Heals All Wounds: Obstacles in Glaucoma Surgery from an Asian Perspective

Glaucoma is the leading cause of irreversible blindness worldwide and is a particular burden on the Asian population. Glaucoma surgeries such as trabeculectomy and glaucoma drainage implants are routinely performed to lower intraocular pressure (IOP) to prevent disease progression. However, scarring of the filtering bleb limits their long-term success and Asian eyes are more at risk. Although this is so, many existing studies have been done on Caucasian patients, but few have focused solely on Asian patients. Intraoperative anti-metabolites such as Mitomycin-C (MMC) and 5-Fluorouracil (5-FU) are the current mainstay of adjunctive treatments to reduce scarring, and in this review, we evaluate the evolution, benefits and side effects of these agents. Recently, newer methods of wound modulation including anti-vascular endothelial growth factor (VEGF) agents and collagen implants are also being investigated as part of a multi-pronged approach to tackle this problem. Some opportunities exist to limit scarring post-operatively, but it is an ongoing battle.

Needle bleb revision with bevacizumab and mitomycin C compared with mitomycin C alone for failing filtration blebs

PURPOSE

To report the 6-month comparative outcomes and bleb morphology for needle revision with bevacizumab and mitomycin C (MMC) versus MMC alone of failed trabeculectomy and ExPRESS shunt blebs.

METHODS

Patients undergoing bleb needle revision procedures were enrolled in this study. All patients received a subconjunctival injection of 0.1 mL MMC (0.4 mg/mL) mixed with 0.1 mL preservative-free lidocaine (1%) at the beginning of the procedure. The patients were randomized into 2 cohorts assigned to receive either 1.0 mg (0.04 mL of 25 mg/mL) subconjunctival bevacizumab (treatment group) or 0.04 mL of balanced salt solution (control group) injected in an identical manner posterior to the bleb after the bleb needling. Success was defined as ≥20% reduction in intraocular pressure (IOP) without any IOP-lowering medications. Qualified success was defined as ≥20% reduction of IOP with IOP-lowering medications. Failure was defined as IOP>21 mm Hg, IOP reduction <20%, or need for additional surgery. Bleb morphology was classified using the Indiana Bleb Appearance Grading Scale.

RESULTS

Six months postoperatively, in treatment group (n=29), 57% of patients achieved complete success, and 43% failed. In control group (n=29), 41% of patients achieved complete success, 7% achieved qualified success, and 52% failed. The difference in success rates between the 2 groups was not statistically significant (P=0.35). At 6 months, the mean IOP was 11.52 in treatment group and 12.83 in control group (P=0.45); patients in treatment group were on a mean of 0.16 medications as compared with 0.58 medications in control group (P=0.058). For bleb morphology of treatment group compared with control group, the blebs had less vascularity (0.76 vs. 1.20, respectively, on a scale of 0 to 4, P<0.05) and greater extent (2.68 vs. 2.36, on a scale of 0 to 3, P=0.022) in treatment group.

CONCLUSIONS

There was no significant difference between the success rates and IOPs at postoperative month 6 between treatment and control groups. Postoperative blebs in the treatment group were less vascular and had greater extent.

Current concepts in the treatment of vitreous block, also known as aqueous misdirection

Vitreous block (VB), a rare secondary angle-closure caused by anterior rotation of the ciliary body, occurs in a variety of settings, but most frequently after glaucoma filtering surgery. The etiology remains unclear, but choroidal expansion and anterior vitreous abnormalities have been proposed. In the past, treatment of VB has yielded high rates of failure and recurrence. Advancements in surgical techniques, however, have led to improved visual outcomes. We review the history of this condition and present a stepwise approach to its diagnosis and treatment using modern imaging modalities and surgical techniques.

Retrobulbar diversion of aqueous humor: clinical feasibility studies

INTRODUCTION

The purpose of this study is to clinically evaluate a new form of glaucoma tube shunt drainage system. Tube shunts play an important role in management of advanced glaucoma, but eventually many blebs may become encapsulated and impervious to aqueous humor. This pilot study analyzed clinical efficacy of retrobulbar diversion of aqueous, either directly from anterior chamber (AC) or existing encapsulated blebs (EB), into the retrobulbar space (RS).

METHODS

Nineteen patients with intractable glaucoma underwent retrobulbar fenestrated implant surgery (16 with EB-to-RS and 3 AC-to-RS). Intraocular pressure, glaucoma medications, and acuity were assessed relative to preoperative baseline values by paired t test preoperatively and bimonthly up to 2 years. Preoperative and postoperative values were compared by paired t test.

RESULTS

Surgical patients (7 male, 12 female; mean, 62±3.3 y; progressive study entry; mean follow-up, 18.2 mo) maintained substantial intraocular pressure reduction, from preoperative mean 33.1±2.0 mm Hg to a sustained bimonthly mean of 14.6±1.6 mm Hg (14.6±1.1, 16.4±1.7, 13.9±1.2, 13.0±1.1, 13.3±2.0, 14.0±1.1, 12.2±2.2, 13.9±2.0, 15.1±1.4, 17.6±1.6, 15.6±2.0, and 16.0±1.6 at months 2 to 24, respectively; all P<0.00001). Acuity remained stable. Glaucoma medications were reduced from 2.8±0.3 to a bimonthly mean of 0.56±0.26 medications through 24 months (P<0.0001).

CONCLUSIONS

Retrobulbar shunts can divert aqueous from the AC into the RS, overcoming (through secondary EB-RS) and potentially obviating (through primary AC-RS) the ocular hypertension resulting from fibrotic plate encapsulation.

Wound Healing Modulation in Glaucoma Filtration Surgery-Conventional Practices and New Perspectives: The Role of Antifibrotic Agents (Part I)

Glaucoma filtration surgery is regularly performed for the treatment of glaucoma and trabeculectomy is often regarded as the ‘gold standard' glaucoma operation. The biggest risk of failure of the operation is bleb scarring. The advent of anti-fibrotic agents, such as mitomycin C (MMC) and 5-fluorouracil (5FU) has vastly prolonged the longevity of the bleb, but concerns remain regarding the potential increase in postoperative complications. More selective therapeutic targets have therefore been explored. One of these is vascular endothelial growth factor (VEGF) inhibition. Vascular endothelial growth factor inhi bition has a role not only in sub conjunctival angiogenesis inhi bition but also it has direct anti-fibrotic properties. Newer phar macological compounds and materials have also been developed in recent years in attempt to modulate the wound healing in different ways after glaucoma surgery. These include physical barriers to scarring and vehicles for sustained release of pharmacological agents, and early promising results have been demonstrated. This two-part review will provide a discussion of the application of anti-fibrotic agents in glaucoma filtration surgery and evaluate the newer agents that have been developed.

How to cite this article: Fan Gaskin JC, Nguyen DQ, Ang GS, O'Connor J, Crowston JG. Wound Healing Modulation in Glaucoma Filtration Surgery–Conventional Practices and New Pers pectives: The Role of Antifibrotic Agents (Part I). J Curr Glaucoma Pract 2014;8(2):37-45.

[Modern filtration surgery. An update]

Preoperative treatment with steroids and nonsteroidal anti-inflammatory drugs increases the success of filtration surgery. Surgery with the patient under subconjunctival anesthesia is safe. Intraoperative application of mitomycin C is state of the art and enhances success rates. Perioperative use of bevacizumab seems to attenuate postoperative fibrosis. Postoperative hypotension is avoided by stable fixation of the scleral flap followed by stepwise controlled suturelysis or release. Transconjunctival flap suturing allows fast and simple treatment of overfiltration. The shorter the time lag between trabeculectomy and subsequent cataract surgery the higher the probability of bleb failure will be. The number of antiglaucomatous drugs and severity of glaucomatous damage before surgery correlate with the probability of failure and blindness.