Four-year results of a minimally invasive transscleral glaucoma gel stent implantation in a prospective multi-centre study

Long-term effectiveness and safety of XEN45 in open-angle glaucoma patients

BACKGROUND

To investigate the long-term effectiveness and safety of XEN45 implant, either alone or in combination with phacoemulsification, in eyes with open-angle glaucoma (OAG).

METHODS

Retrospective and single center study conducted on consecutive OAG patients who underwent a XEN45 implant between February-2017 and December-2021. The primary endpoint was the mean intraocular pressure (IOP) lowering from preoperative values. Surgical success was defined as an IOP-lowering from preoperative values ≥ 20% and an IOP absolute value between 6 and 13 mm Hg, without (Complete-success) or with (Qualified-success) antiglaucoma medications.

RESULTS

A total of 158 eyes (34 (21.5%) eyes XEN-solo and 124 (78.5%) XEN + Phaco) were included. The median follow-up time was 28.5 months. In the overall study population, the mean preoperative IOP was significantly lowered from 19.4 ± 6.5 mm Hg to 12.4 ± 5.0 mm Hg. The mean preoperative (95% confidence interval) IOP was significantly lowered from 21.3 (19.3-23.2) mm Hg and 18.8 (17.7-20.0) mm Hg to 12.0 (10.4-13.6) mm Hg and 12.5 (11.6-13.5) mm Hg in the XEN-Solo and XEN + Phaco groups, respectively (p < 0.0001 each, respectively). The mean number of ocular-hypotensive medications was significantly reduced in the overall study sample (from 3.4 ± 0.9 to 0.9 ± 1.3, p < 0.0001), XEN-Solo (from 3.5 ± 1.1 to 0.6 ± 1.0, p < 0.0001, and XEN + Phaco (from 3.4 ± 1.1 to 0.9 ± 1.3, p < 0.0001) groups. Eighty-four (53.2%) eyes were categorized as success, with 49 (58.3%) classified as complete success. Eighty-one (51.3%) eyes underwent needling and 15 (9.5%) eyes required an additional surgical procedure. One (0.6%) eye had endophthalmitis.

CONCLUSION

XEN implant, either alone or in combination with phacoemulsification significantly lowered IOP and reduced the need of ocular-hypotensive medication, while maintaining a good safety profile.

Three-year clinical outcome of XEN45 Gel Stent implantation versus trabeculectomy in patients with open angle glaucoma

OBJECTIVE

To reliably compare the three-year clinical outcome and safety of XEN45 Gel Stent implantation (XEN) vs. trabeculectomy (TRAB) in patients with glaucoma.

SUBJECT/METHODS

We conducted a retrospective cohort study with patients with primary open angle or pseudoexfoliation glaucoma with uncontrolled intraocular pressure (IOP) undergoing XEN or TRAB at the Innsbruck University Clinic of Ophthalmology and Optometry, Austria and analysed changes in IOP, numbers of IOP-lowering medications, and complete surgical success (i.e., IOP ≤ 18 mmHg, ≥20% IOP reduction and not requiring IOP-lowering medication) up to 36 months postoperatively.

RESULTS

Between 2013 and 2019, we performed XEN Gel Stent implantation in 58 eyes and trabeculectomy in 84 eyes. From baseline to 36 months, mean IOP decreased from 23.4 to 13.8 mmHg (mean reduction 35%, 95% confidence interval 23-48%, p < 0.001) in the XEN group and from 25.1 to 11.2 mmHg (mean reduction 50%, 41-60%, p < 0.001) in the TRAB group. TRAB provided higher IOP reduction than XEN Gel Stent implantation at 12, 24, and 36 months (all p < 0.05). In XEN versus TRAB, IOP-lowering medication was required by 98.3% vs. 97.6% before surgery (p = 0.781), differed significantly at month 12 (43.2% vs. 2.0%, p < 0.001)but not at month 24 or 36. Complete surgical success was achieved in 40.0% vs. 62.8% at month 24 (adjusted odds ratio 2.70; 1.04-7.00, p = 0.040) and 27.3% vs. 56.8% at month 36 (4.36; 1.25-15.18, p = 0.021).

CONCLUSION

Compared to XEN, TRAB was associated with lower intraocular pressure, less IOP-lowering medication, and higher probability of achieving complete surgical success over a 36-month follow-up period.

XEN45 gel stent in the treatment of pigmentary glaucoma: A two-year follow-up

PURPOSE

To investigate safety and efficacy of the XEN gel stent in patients with pigmentary glaucoma (PG).

METHODS

A retrospective analysis of 26 eyes of 19 patients with PG undergoing XEN gel stent implantation was performed. Best-corrected visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were analyzed preoperatively, and at 2 weeks and 3, 6, 12, and 24 months after surgery. Success, needling, and complications were analyzed. Complete success was defined as an IOP reduction of >20% and achieving a target IOP of ≤18, ≤15, or ≤12 mmHg without antiglaucoma medication. Qualified success was indicated if the IOP target was reached with or without medication.

RESULTS

Mean IOP decreased significantly from 27.6 ± 14.3 (standard deviation, SD) mmHg to 14.3 ± 4.6 mmHg after one year (p < 0.001) and 15.1 ± 2.7 mmHg (p < 0.001) after two years. The median number of hypotensive drugs declined significantly from 4 (range: 3-5) to 0 (0-2) and 0 (0-3) after one and two years, respectively. After two years, complete success with an IOP of ≤18 mmHg and ≤15 mmHg was achieved in 73.1% and 61.5%, respectively. Half of the eyes required needling after a median time of 8 months (0.5-34 months). No sight-threatening complications were observed.

CONCLUSION

The XEN gel stent is a safe and effective surgical treatment option for PG. Needling is an important part of the procedure and should be communicated preoperatively to the patients.

Swiss Multicenter Ab Interno XEN45 Gel Stent Study: 2-Year Real-World Data

INTRODUCTION

The aim of this study was to investigate the 2-year postoperative efficacy of the XEN45 Gel Stent by evaluating the reduction of intraocular pressure (IOP) and the need for eye pressure-lowering medications in a multicenter setting in Switzerland.

METHODS

Patients with various types of glaucoma who received a XEN45 Gel Stent with or without combined phacoemulsification cataract surgery at five hospitals in Switzerland were retrospectively enrolled. Pre- and postoperative IOP, the number of antiglaucoma medications, and the need of subsequent interventions to control IOP were assessed. The success rate was defined as a ≥ 20% reduction of IOP 2 years postoperatively without the need for subsequent glaucoma surgery.

RESULTS

A total of 345 eyes were included: 44.3% with primary open-angle, 42.0% pseudoexfoliation, and 13.7% with other types of glaucoma. Of these, 206 patients were followed for 2 years. Preoperatively, the mean IOP was 26.3 ± 8.9 mmHg and the mean number of antiglaucoma medications administered was 3.0 ± 1.3. Two years postoperatively, the success rate was 66.0% (95% confidence interval 59.3-72.1%), the IOP had dropped by 43.8% to 14.8 ± 5.7 mmHg, and the number of medications was reduced by a mean of 2.0 ± 1.7 per day. Postoperative complications and the need for interventions remained low.

CONCLUSION

The XEN45 Gel Stent successfully reduced IOP and the number of antiglaucoma drugs in most patients at 2 years postoperatively.

Xen-DS: a novel technique of ab externo Xen implantation augmented with a modified deep sclerectomy for surgical treatment of glaucoma

PURPOSE

The Xen gel stent is a surgical glaucoma device which creates a subconjunctival filtering bleb, which has demonstrated good intraocular pressure (IOP) lowering and safety. Nonetheless, bleb-related problems have been reported. We present a case series of ab externo Xen procedures augmented with a deep intra-scleral lake, aiming to improve both IOP-lowering and post-operative management.

METHODS

A retrospective review of 20 patients who underwent combined Xen gel stent implantation with modified deep sclerectomy at our institution from June to November 2022, with a 6-month follow-up period. We reviewed demographics, past ocular history, visual acuity (VA), IOP, visual fields, glaucoma medication use, complications, and perioperative information.

RESULTS

20 eyes of 20 patients, with a mean age of 67.45 ± 14.38 underwent surgery. Pre-operative initial IOP was 24.5 ± 7.96 mmHg, improving to 11.50 ± 2.96 mmHg at 6 months; a change of -12.89 ± 8.34 mmHg and a mean decrease of 51.13 ± 20.15% (p < 0.0001) Patients were on 3.1 ± 0.72 glaucoma medications pre-operatively, improving to 0.72 ± 1.27 at 6 months (p < 0.0001). Visual field mean deviation was -13.99 ± 9.98 dB pre-operatively and -10.27 ± 9.06 dB at 6 months, with VA of 0.287 ± 0.69 pre-operatively and 0.31 ± 0.76 LogMAR post-operatively. No patients required bleb needling. 2 patients underwent subsequent bleb revision surgery. 2 patients developed choroidal effusions, which were managed conservatively with good visual outcomes.

CONCLUSION

In this preliminary study, we have found the modification of Xen gel stent implant surgery with a modified deep sclerectomy to offer good IOP lowering, with low rates of bleb needling and a good safety profile.

Navigating hypotony challenges with XEN gel implantation

INTRODUCTION

The XEN Gel, a hydrophilic tube meticulously crafted to adhere to the principles of the Hagen - Poiseuille law, is designed to facilitate efficient aqueous shunting without inducing hypotony. Implantable ab interno or ab externo, with or without conjunctival opening, the device shows no significant outcome differences. Despite numerical hypotony signaling failure, patients may fare well below 6 mmHg.

AREAS COVERED

This review provides insights into device variability, challenges related to hypotony, associated risk factors, and hypotony management.

EXPERT OPINION

The progressive evolution of the XEN Gel constitutes a significant advancement in the field of glaucoma management. Comparative studies investigating diverse implantation methodologies, particularly the ab interno and closed conjunctival approaches, highlight the device versatility in addressing individual patient needs. Exploring hypotony from both statistical and clinical perspectives challenges the traditional view of intraocular pressure as a straightforward success or failure indicator. The incidence of hypotony-related issues varies between device models, emphasizes the need for an individualized approach during device selection. Overall, understanding the dynamics of hypotony is crucial for optimizing the outcomes of XEN Gel implantation.

XEN®-45 implantation for refractory uveitic glaucoma

PURPOSE

To evaluate the efficacy of XEN®-45 gel stent ab interno implantation for medically uncontrolled uveitic glaucoma.

METHODS

Retrospective analysis of 25 eyes receiving XEN® gel stent for medically uncontrolled uveitic glaucoma from February 2019 to February 2023 with recording of intraocular pressure (IOP) values, ocular hypotensive medication, requirement for revision or secondary surgery and complications. Prerequisites for XEN® implantation were a clear cornea, an open iridocorneal angle and an unscarred, mobile conjunctiva at the implantation site. Minimum follow-up required for inclusion was 3 months. The primary outcome measure was IOP compared to baseline. Complete and qualified success were defined as final IOP of ≤ 18 mmHg without or with topical antiglaucomatous treatment, respectively. Failure was defined as IOP > 18 mmHg on two consecutive visits, IOP reduction < 20%, persisting complications from hypotony and open conjunctival bleb revision. Further glaucoma surgical intervention was defined as complete failure.

RESULTS

Mean preoperative IOP was 35.3 ± 10.9 mmHg on 2.9 ± 0.9 topical antiglaucomatous agents. 19 of 25 patients (76%) received additional oral acetazolamide. 19 eyes were pseudophakic, 5 eyes phakic and 1 aphakic. Early postoperatively, mean IOP reduced to 7.7 ± 3.0 mmHg (75.8% reduction). At final follow-up (mean 17.7 months) mean IOP was 12.0 ± 3.8 mmHg (62.5% reduction) on 0.2 ± 0.6 medications. Six eyes (24%) required bleb revision at mean 28 weeks and therefore were categorized as failure. One eye failed despite bleb revision and restart of topical ocular hypotensive medication. Three other eyes (12%) had IOP spikes with uveitis flare-ups. Transient hypotony complications occurred in 32%. At final follow-up, 18 eyes (72%) achieved complete success and one eye (4%) qualified success.

CONCLUSION

The XEN® gel stent effectively reduced IOP in uncontrolled uveitic glaucoma, with 72% complete success. Bleb revision was required in 24%. IOP spikes occurred in 12% despite functioning blebs. Further follow-up is needed to determine long-term outcomes.

Effectiveness and safety of XEN63 in patients with primary-open-angle glaucoma

This paper evaluates the effectiveness and safety of XEN63 stent, either standalone or in combination with phacoemulsification, in patients with primary open-angle glaucoma (POAG). Eighty eyes from 80 patients with medically uncontrolled POAG were assigned to undergo XEN63 implant. The primary outcome was the surgical success, defined as an intraocular pressure (IOP) lowering from preoperative values ≥ 20% and an IOP absolute value between 6 and 18 mmHg, with or without antiglaucoma medications. Forty-three (53.7%) eyes underwent XEN63-standalone and 37(46.2%) eyes a XEN63 + Phacoemulsification procedure. Success rate was 68.8% (55/80) eyes in the overall study sample, 69.8% (30/43) eyes in the XEN63-standalone group; and 67.6% (25/37) eyes in the XEN63 + Phaco group (p = 0.6133). Preoperative IOP was significantly lowered from 22.1 ± 4.9 mmHg and 19.8 ± 3.7 mmHg to 14.7 ± 5.3 mmHg and 13.8 ± 3.4 mmHg in the XEN63-standalone and XEN63 + Phaco groups, respectively (p < 0.0001 each, respectively); without significant differences between them at any of the time-points measured. Preoperative number of ocular-hypotensive drugs was significantly reduced from 2.3 ± 0.8 to 0.3 ± 0.7 drugs, from 2.5 ± 0.7 to 0.3 ± 0.7 drugs; and from 2.0 ± 0.8 to 0.3 ± 0.7 drugs, in the overall, XEN63-standalone, and XEN63 + Phaco groups, respectively. Regarding safety, 3(42.5%) eyes had transient hypotony at some point during the study, although only in one (1.2%) eye was clinically significant. Four (5.0%) eyes underwent a needling, 4 (5.0%) eyes underwent surgical-bleb-revision, 1 (1.2%) eye required a device replacement and 1 (1.2%) eye a device removal due to maculopathy. XEN63, either alone or in combination with phacoemulsification, significantly lowered IOP and reduced the number of ocular hypotensive medications. The rate of ocular hypotony was relatively high, although it was clinically relevant only in one eye.

Short-Term Outcomes of XEN45 Standalone versus Combined with Phacoemulsification in Open-Angle Glaucoma Patients: A Retrospective Study

The XEN45 is a minimally invasive glaucoma surgery device commonly used in clinical practice. This retrospective study included consecutive patients with open-angle glaucoma who underwent a XEN45 implant with mitomycin C, either alone or in combination with phacoemulsification, between June 2015 and March 2021. The primary end point was the mean change in intraocular pressure (IOP) from the baseline to month 6. A total of 677 eyes, 395 (58.3%) in the XEN alone group and 282 (41.7%) in the XEN+Phaco group, were included in this study. The preoperative IOP was significantly lowered from 28.7 ± 8.6 mmHg and 25.4 ± 6.9 mmHg to 13.5 ± 5.0 mmHg and 13.5 ± 4.1 mmHg at month 6 in the XEN solo and XEN+Phaco groups, respectively, with p < 0.0001 each. The mean (95% confidence interval) number of ocular hypotensive medications was significantly reduced from 3.3 (3.2-3.4) to 0.2 (0.1-0.2) and from 3.1 (2.9-3.2) to 0.2 (0.1-0.2) in the XEN solo and XEN+Phaco groups, respectively, with p < 0.0001 each. Needling was performed in 228 (33.7%) eyes. Conclusions: the XEN implant significantly reduces both IOP and the number of ocular hypotensive medications. IOP lowering was higher in the XEN solo group than in the XEN+Phaco one, although such a difference was only evident during the first month after surgery.

Minimally Invasive Glaucoma Surgery: Latest Developments and Future Challenges

The development of minimally invasive glaucoma surgeries (MIGSs) was intended to provide safe and modestly efficacious modalities for early intervention of mild-to-moderate glaucoma, with minimal trauma and rapid recovery. They were mainly ab interno procedures that reduce intraocular pressure by facilitating the aqueous outflow by bypassing the trabecular meshwork resistance, reinforcing the uveoscleral flow via the supraciliary space, and reducing aqueous production by the ciliary body. While the cumulating evidence helps shape the role of the available MIGS, the exponential new development and advancement in this field has expanded the territory of MIGS. Apart from developing subconjunctival MIGS filtration devices (Xen gel stent and PRESERFLO MicroShunt), there is a tendency to revisit the "traditional" MIGS for alternative use and to modify the procedures with consideration of the fundamental aqueous outflow physiology. Combined MIGS has also been suggested, based on the theory that their different mechanisms may provide additive or synergistic effects. The advancement of laser procedures is also promising and could supplement unmet needs along the glaucoma treatment algorithm. This review examines the broad array of MIGS, updates the recent findings, discusses their potential alternative applications, and explores future challenges.

Results of open bleb revision as management of primary bleb failure following XEN 45 gel stent and Preserflo™ Microshunt

PURPOSE

The success of filtering surgery as in XEN-Gel-Stent (XEN) and Preserflo-Microshunt (PF) depends mainly on a functioning bleb. Primary bleb failure (PBF) is not uncommon and can be treated with needling or open bleb revision (OBR). The aim of the study is to compare surgical outcomes of OBR after XEN and PF.

METHODS

Eyes which received OBR as management of PBF following implantation of XEN or PF were retrospectively included. Intraocular pressure (IOP), number of IOP lowering medications (NoM), and success rates (SR) were compared between groups. Complete and qualified success were defined as IOP ≤18mmHg and a reduction of >20%, without and with medications, respectively.

RESULTS

29 eyes after XEN and 23 eyes after PF were included. Six months following OBR, IOP reduced from 24.2±4.7 to 13.5±4.6 after XEN and from 27.3±8.7 to 15.9±5.8mmHg after PF (both p<0.001). NoM did not change (0.7±1.3 to 0.4±0.8 after XEN and 1.2±1.3 to 1.0±1.5 after PF, p>0.05 for both). Complete SR were higher after XEN than after PF (58.6% vs. 30.4%, p=0.04). Complications were mild and managed mainly conservatively. Additional glaucoma surgery was needed in 17% and 30% of eyes after XEN and PF, respectively (p=0.26).

CONCLUSION

Although OBR was effective as management of PBF following XEN and PF, SR were higher after XEN than after PF along with comparable safety profile. The change of the surgical approach from ab interno during XEN-Implantation to ab externo during OBR seems to enhance SR compared to PF, where both interventions are done ab externo.

Intermediate Outcomes of the Novel 63-μm Gelatin Microstent versus the Conventional 45-μm Gelatin Microstent

PURPOSE

To determine intermediate intraocular pressure (IOP)-lowering and adverse event profile of the 63-μm gelatin microstent (Xen63) with mitomycin C (MMC) compared with the 45-μm gelatin microstent (Xen45) with MMC.

DESIGN

Single center, consecutive, retrospective cohort study.

PARTICIPANTS

Eighty-four glaucomatous eyes (42 63-μm gelatin microstent and 42 45-μm gelatin microstent) with or without previous subconjunctival glaucoma surgery.

METHODS

Consecutive eyes that underwent 63-μm gelatin microstent implantation with MMC from February 2020 to June 2021 were compared with eyes that underwent 45-μm gelatin microstent implantation with MMC. Standalone and combined cases with phacoemulsification were included.

MAIN OUTCOME MEASURES

Primary outcome was the hazard ratio of failure of 45-μm gelatin microstent vs. 63-μm gelatin microstent eyes at 12 months, with failure defined as 2 consecutive IOPs, (1) >17 mmHg, (2) <6 mmHg with 2 lines of vision loss, or (3) <20% reduction from baseline IOP, without (complete) or with (qualified) glaucoma medications. Secondary outcomes included IOP thresholds of 14 mmHg and 21 mmHg, postoperative IOP, medications, adverse events, interventions, and reoperations.

RESULTS

The complete success rate was higher in the 63-μm gelatin microstent group (59.5% vs. 28.6%, P = 0.009) at the primary IOP threshold of 6 to 17 mmHg but did not differ significantly for qualified success (66.7% vs. 45.2%, P = 0.08). The crude hazard ratio of failure of 45-μm gelatin microstent relative to 63-μm gelatin microstent was 2.28 (95% confidence interval [CI], 1.21-4.32), and the adjusted hazard ratio was 7.90 (95% CI, 2.12-29.43). 63-μm gelatin microstent eyes had significantly lower mean IOP (12.7 ± 4.8 vs. 15.5 ± 5.1 mmHg, P = 0.001) and fewer medication classes (0.6 ± 1.1 vs. 1.7 ± 1.6 medications, P = 0.0005), with the degree of reduction in IOP and medication count being significantly greater in 63-μm gelatin microstent eyes. There were 28 and 21 distinct interventions in 63-μm gelatin microstent and 45-μm gelatin microstent eyes respectively, with 11.9% of eyes undergoing needling in each group. There were 34 and 19 distinct adverse events, in 63-μm gelatin microstent and 45-μm gelatin microstent eyes, respectively, most of which were early and transient. Nine Xen63 eyes (21.4%) and 6 45-μm gelatin microstent eyes (14.3%) underwent reoperation.

CONCLUSIONS

63-μm gelatin microstent resulted in higher surgical success rates and fewer medications compared with 45-μm gelatin microstent. This was tempered by more postoperative interventions and adverse events, although most were transient.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

[Real-world outcomes of glaucoma surgical procedures for open-angle glaucoma]

This article provides an overview of real-world outcomes in glaucoma surgical procedures. While randomized clinical trials provide valuable insights, they do not fully reflect real-world clinical practice. Real-world studies enable the evaluation of outcomes in uncontrolled settings and play a crucial role in counselling and decision-making for glaucoma treatment. By examining real-world data the article aims to identify rare adverse events that may go unnoticed in controlled clinical trials. The focus is on assessing the effectiveness and safety of glaucoma surgical procedures beyond the controlled trial setting.

Efficacy and safety of the XEN45 implant in glaucoma surgery: Retrospective study of our first 73 cases

OBJECTIVE

To analyze the results of the Xen45 implant in our hospital center, both in terms of efficacy and safety.

METHODS

Observational, retrospective, single-center study of patients undergoing Xen45 surgery at the University Hospital of Jaén between January 1, 2018 and June 31, 2021.

RESULTS

A total of 73 patients were implanted with the Xen45 device (48 with in combined surgery with phacoemulsification of the crystalline lens and 25 standalone Xen45 surgery). IOP decreased from 19.9 ± 4.9 mmHg at the first visit to a mean of 17.1 ± 5.3 (P = .001) at the sixth month. Drug use required between the first visit and Xen implantation was reduced from 2.1 ± 0.9 to 0.6 (P < .000). A second surgery was necessary in 18 patients (26.6%) in the first 6 months.

CONCLUSIONS

Glaucoma surgery by Xen45 implant, alone or combined with cataract surgery, is an effective and safe procedure for IOP lowering.

Outcomes of XEN Stent in Patients With Glaucoma and Previous Corneal Transplantation

PRCIS

The XEN stent safely and effectively controls intraocular pressure in select patients with history of corneal transplantation.

PURPOSE

Glaucoma is a common complication after corneal transplantation and can be difficult to manage in these patients. This study reports outcomes of XEN stent implantation in eyes with glaucoma in the setting of previous corneal transplantation.

PATIENTS AND METHODS

Noncomparative retrospective case series including eyes with a history of corneal transplantation and subsequent XEN stent implantation by a single glaucoma surgeon in Surrey, British Columbia, between 2017 and 2022. The analysis included patient demographics, pre and postoperative intraocular pressure (IOP), pre and postoperative glaucoma medications, peri and postoperative complications and interventions, and incidence of repeat corneal transplantation and additional glaucoma procedures to control IOP.

RESULTS

Fourteen eyes with previous cornea transplantation underwent XEN stent implantation. Mean age was 70.1 years (range: 47-85 y). Mean follow-up was 18.2 months (range: 1.5-52 mo). The most common glaucoma diagnosis was secondary open angle glaucoma (50.0%). There was a significant reduction in IOP and the number of glaucoma agents at all postoperative time points ( P < 0.05). IOP decreased from 32.7 ± 10.0 mm Hg at baseline to 12.5 ± 4.7 mm Hg at the most recent follow-up. Glaucoma agents decreased from 4.0 ± 0.7 to 0.4 ± 1.0. Two eyes required additional glaucoma surgery to control IOP, with an average time to reoperation of 7 weeks. Two eyes underwent repeat corneal transplantation, with an average time to reoperation of 23.5 months.

CONCLUSIONS

In selected patients with previous corneal transplants and refractory glaucoma, the XEN stent was safely implanted and effectively reduced IOP in the short term.

Effectiveness and Safety of Xen Gel Stent in Glaucoma Surgery: A Systematic Review of the Literature

Although topical medical therapy and selective-laser-trabeculoplasty represent the treatments of choice to reduce intraocular pressure, many patients do not achieve adequate glaucoma control; therefore, they require further options and eventually surgery. Trabeculectomy is still considered the gold standard, but the surgical management of glaucoma has undergone continuous advances in recent years, XEN-gel-stent has been introduced as a safer and less traumatic means of lowering intraocular pressure (IOP) in patients with open-angle glaucoma (OAG). This study aimed to review the effectiveness and safety of clinical data on XEN-stent in OAG patients with a Synthesis-Without-Meta-analysis (SWiM) methodology. A total of 339 studies were identified following a literature search adhering to PRISMA guidelines and, after evaluation, 96 studies are discussed. XEN63 and XEN45 device data were collected both short and long term. In addition, this document has evaluated different aspects related to the XEN implant, including: its role compared to trabeculectomy; the impact of mitomycin-C dose on clinical outcomes; postoperative management of the device; and the identification of potential factors that might predict its clinical outcomes. Finally, current challenges and future perspectives of XEN stent, such as its use in fragile or high myopia patients, were discussed.

New XEN63 Gel Stent Implantation in Open-Angle Glaucoma: A Two-Year Follow-Up Pilot Study

Purpose

The XEN gel stent was developed to reduce the risks of filtration surgery by standardizing the outflow of aqueous humor into the subconjunctival space. Recently, a modified version of the XEN63 gel stent was introduced. The goal of this study was to assess its efficacy and safety.

Methods

This is a prospective, nonrandomized, observational, consecutive case series study at a single tertiary centre. Patients with open-angle glaucoma with above target intraocular pressure (IOP) despite maximal tolerated medication were included. The primary outcome was a change of median IOP. Secondary outcomes included a change in the number of medications, complete success, needling and complication rates. Success was defined as a lowering of IOP > 20% from baseline and IOP ≤ 14 mmHg. Complete success indicated that the target IOP was reached without medications.

Results

Six patients were included. The median IOP decreased from 35.5 mmHg (25.0-40.0 mmHg) at baseline to 11.5 mmHg (4.0-15.0 mmHg, p = 0.03), and median IOP-lowering medication was reduced from 4.0 (3.0-4.0) at baseline to 0 (0-1.0, p = 0.03) after two years. Five patients (83.0%) had a complete success after two years. Two patients (33.0%) required a needling procedure. Three patients (50.0%) required an intervention due to symptomatic hypotony within the first three weeks postoperatively. Hypotony resolved completely or was asymptomatic after three months.

Conclusion

Our study demonstrated a statistically significant reduction in both IOP and number of IOP-lowering medications. Complications were well manageable and had no long-term sequelae.

Outcomes of Open Bleb Revision After PreserFlo MicroShunt Failure in Patients With Glaucoma

PRCIS

After the open bleb revision following PreserFlo, the mean postoperative intraocular pressure (IOP) was lowered from 26.4 ± 9.9 mm Hg to 12.9 ± 5.6 mm Hg at 1 month and 15.9 ± 4.1 mm Hg at 12 months.

PURPOSE

The purpose of this study was to evaluate the effectiveness and safety of an open bleb revision with mitomycin- C (MMC) for bleb fibrosis after PreserFlo MicroShunt implantation.

PATIENTS AND METHODS

We performed a retrospective analysis of 27 consecutive patients with bleb fibrosis after PreserFlo MicroShunt Implantation that underwent an open revision with MMC 0.2 mg/mL applied for 3 minutes at the Department of Ophthalmology of the Mainz, University Medical Center, Mainz, Germany. Demographic data, such as age, sex, glaucoma type, number of glaucoma medications, IOP before and after PreserFlo implantation and revision, complications, and reoperations within 12 months, were analyzed.

RESULTS

Twenty-seven patients (27 eyes) received an open revision after previous PreserFlo Microshunt implantation and consecutive bleb fibrosis. The mean preoperative IOP was 26.4 ± 9.9 mm Hg before revision, 7.0 ± 2.7 mm Hg ( P < 0.001) in the first week after the revision, and 15.9 ± 4.1 mm Hg at 12 months ( P = 0.02). Four patients needed IOP-lowering medication after 12 months. One patient had a positive Seidel test and needed a conjunctival suture. Four patients required a second procedure due to recurring bleb fibrosis.

CONCLUSIONS

At 12 months, open revision with MMC for bleb fibrosis after failed PreserFlo implantation effectively and safely reduced IOP with a similar medication burden.

XEN®-63 Compared to XEN®-45 Gel Stents to Reduce Intraocular Pressure in Glaucoma

The XEN® gel stent reduces intraocular pressure (IOP) in glaucoma. XEN®-45 is widely used; the newer XEN®-63 has a larger lumen targeting potentially lower IOP outcomes. We retrospectively compared the first 15 XEN®-63 cases to 15 matched XEN®-45 controls. With a preoperative IOP of 18.1 ± 3.9 mmHg (mean ± SD) and a final IOP of 9.1 ± 2.0 mmHg, XEN®-63 implantation resulted in an IOP reduction of 44.6 ± 16.5%. Similarly, with a preoperative IOP of 18.3 ± 4.5 mmHg and a final IOP of 10.3 ± 2.1 mmHg, XEN®-45 implantation resulted in an IOP reduction of 40.1 ± 17.2%. The median follow-up period was 204 days (range 78-338 days) for the XEN®-63 group and 386 days (range 99-1688 days) for the XEN®-45 group. In total, 5/15 eyes of each group underwent open conjunctival bleb revision within the period of observation. Three eyes of the XEN®-63 group had secondary glaucoma surgery. One eye in the XEN®-63 group and three eyes in the XEN®-45 group required a restart of antiglaucomatous medication. In conclusion, both stents effectively lower IOP and medication. XEN®-63 achieved a slightly lower IOP over a short follow-up. Complication and revision rates were similar.

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.

[Comparison of new and old procedures in glaucoma surgery : Trabeculectomy, Preserflo and XEN]

Glaucoma is one of the most frequent causes of irreversible blindness worldwide. The main risk factor of the disease is an individually too high intraocular pressure and pressure reduction is still the only established treatment. If conservative pressure reduction and adherence are insufficient, and if the patient is unable to tolerate conservative treatment, surgical procedures become necessary. There are nowadays more than a dozen different surgical procedures for lowering the pressure. This article presents and discusses the procedures that have a subconjunctival pre-equatorial drainage in common. These include trabeculectomy, the XEN-gel implant and the Preserflo microshunt.

Clinical Outcomes of XEN45®-Stent Implantation after Failed Trabeculectomy: A Retrospective Single-Center Study

BACKGROUND

The implantation of a collagen gel micro-stent (XEN45^®) as a minimally invasive form of glaucoma surgery (MIGS) after a failed trabeculectomy (TE) may be an effective option with few risks. This study investigated the clinical outcome of XEN45^® implantation after a failed TE, with follow-up data of up to 30 months.

MATERIALS AND METHODS

In this paper, we present a retrospective review of patients undergoing XEN45^® implantation after a failed TE at the University Eye Hospital Bonn, Germany, from 2012 to 2020.

RESULTS

In total, 14 eyes from 14 patients were included. The mean follow-up time was 20.4 months. The mean time duration between the failed TE and XEN45^® implantation was 110 months. The mean intraocular pressure (IOP) decreased from 17.93 mmHg to 12.08 mmHg after one year. This value increased again to 17.63 mmHg at 24 months and 16.00 mmHg at 30 months. The number of glaucoma medications decreased from 3.2 to 0.71, 2.0, and 2.71 at 12, 24, and 30 months, respectively.

CONCLUSIONS

XEN45^® stent implantation after a failed TE did not lead to an effective long-term decrease in IOP and glaucoma medications in many patients in our cohort. Nevertheless, there were cases without the development of a failure event and complications, and others in whom further, more invasive surgery was delayed. XEN45^® implantation in some failed trabeculectomy cases may, therefore, be a good option, especially in older patients with multiple comorbidities.

Glaucoma Treatment in German Hospitals in 2019

BACKGROUND

Surgical procedures in ophthalmology are subject to fluctuations in their application and are dependent on new developments, availability, and success rates. In the field of glaucoma surgery in particular, numerous new procedures have been introduced over the last few years. So far, hardly any analyses have been done on the current application of these newer procedures. In this paper, we present the extent to which different glaucoma surgery procedures were used in German hospitals in 2019.

METHODS

The quality reports of German hospitals from 2019 were evaluated regarding all glaucoma-specific procedure codes. In particular, laser procedures, "classic" glaucoma procedures, and "modern" procedures such as MIGS (minimally invasive glaucoma surgery) are compared below.

RESULTS

In 2019, 49,031 glaucoma procedures were performed in German hospitals. Numerically, cyclodestructive procedures were used most frequently. MIGS accounted for approximately 10% of procedures according to the available data. Among filtering procedures, about 40% were implant-assisted.

DISCUSSION AND CONCLUSION

On the one hand, the data analyzed show a mixed expansion of the spectrum with newer procedures such as the MIGS and implants; on the other hand, classic procedures such as cyclodestruction are still used. It can be assumed that further shifts in surgical methods will be seen in the coming years.

Long-Term Effectiveness of XEN 45 Gel-Stent in Open-Angle Glaucoma Patients

Purpose

To assess the effectiveness of XEN45, either alone or in combination with phacoemulsification, in open-angle glaucoma (OAG) patients in clinical practice.

Methods

Retrospective and single-center study conducted on OAG patients who underwent XEN45 implant, either alone or in combination with cataract surgery. We compared the clinical outcomes of the eyes of thosewho underwent XEN-solo versus those who underwent XEN+Phacoemulsification. The primary endpoint was the mean change in intraocular pressure (IOP) from baseline to the last follow-up visit.

Results

A total of 154 eyes, 37 (24.0%) eyes that underwent XEN-solo and 117 (76.0%) eyes that underwent XEN+Phacoemulsification, were included. The mean preoperative IOP was significantly lowered from 19.1±5.0 mmHg to 14.9±3.8 mmHg at month-36, p<0.0001. Preoperative IOP was significantly lowered from 21.2±6.2 mmHg and 18.4±4.3 mmHg to 14.3±4.0 mm Hg and 15.2±3.7 mmHg at month-36 in the XEN-solo and XEN+Phacoemulsification groups, p<0.0004 and p=0.0009; with no significant differences between them. In the overall study population, the mean number of antiglaucoma medications was significantly reduced from 2.1±0.8 to 0.2±0.6, p<0.0001. There were no significant differences in the proportion of eyes with a final IOP ≤14 mmHg and ≤16 mmHg between XEN-solo and XEN+Phaco groups (p=0.8406 and 0.04970, respectively). Thirty-six (23.4%) eyes required a needling procedure.

Conclusion

XEN implant significantly lowered IOP and reduced the need of ocular hypotensive medication, while maintaining a good safety profile. Beyond week-1, there were no significant differences in IOP lowering between XEN-solo and XEN+Phacoemulsification groups.

Outcomes of 45 μm gelatin stent surgery over 24-month follow-up

BACKGROUND

The main objectives of this study were to determine whether known risk factors for trabeculectomy failure similarly influence gelatin stent outcomes and to identify surgical factors which may optimise success.

METHODS

A retrospective, observational study was conducted at a single centre in Perth, Western Australia over 24 months. Two-hundred and sixty-two eyes of 207 patients underwent XEN-45 stent surgery with various forms of glaucoma. Surgical and postoperative data on subjects undergoing XEN-45 stent surgery was collated. Intraocular pressure (IOP) reduction success was determined using three criteria: 1; IOP <18 mm Hg, 2: IOP <15 mm Hg and 3: >25% IOP reduction from baseline. Kaplan-Meier, mixed effects Cox Proportional hazard model and Chi-Square test were used to measure survival of functioning stents.

RESULTS

The success rates at a maximum of 2 years after surgery by criteria 1, 2 and 3 were 61.3%, 26.2% and 28.9% in primary open angle glaucoma (n = 243), 18.8%, 16.9%, 21.4% in angle closure glaucoma (n = 11), 0%, 0%, 66.7% in congenital glaucoma (n = 5) and 0% in uveitic glaucoma (n = 3). No significant reduction in success was found in those eyes that had prior ocular surgery (all p > 0.07).

CONCLUSIONS

Prior cataract or trabeculectomy surgery does not appear to adversely affect gelatin stent outcomes over 2 years follow up. Gelatin stent surgery appears to have less IOP reduction effect compared to trabeculectomy at 2 years.

Budget impact analysis of the XEN®63 for the treatment of primary openangle glaucoma in Spain

BACKGROUND AND OBJECTIVE

To evaluate the economic impact in Spain derived from the introduction of the XEN®63 implant as a surgical alternative in the management of primary open angle glaucoma (POAG) with or without cataract in refractory patients.

MATERIALS AND METHODS

A budget impact analysis was designed to estimate the costs of surgical treatment of POAG from the perspective of the Spanish National Health System (NHS), over a time horizon of 1 year. The comparators considered (trabeculectomy, deep non-penetrating sclerectomy, Ahmed valve, iStent inject, Preserflo® microshunt and XEN®45) correspond to those used in Spanish public clinical practice. For the calculation of the target population, market shares and resource use in terms of follow-up visits, additional procedures and post-surgery complications, data from the literature were used and validated with a panel of 4 experts. Unit costs (€ 2021) were obtained from the ESALUD database.

RESULTS

The inclusion of XEN®63 could generate savings of €2,569,737 after one year since its introduction, derived from savings in the cost of the implant and procedure (-€423,120; -0.7%), follow-up visits (-€777,407; -4.5%), additional procedures (-€1,048,145; -20.6%) and post-surgery complications (-€321,065; -14.2%).

CONCLUSIONS

The incorporation of XEN63®in the surgical arsenal for the treatment of refractory POAG with and without cataracts could generate savings for the NHS.

Refractive Changes after Glaucoma Surgery-A Comparison between Trabeculectomy and XEN Microstent Implantation

Best-corrected visual acuity often decreases temporarily or permanently after trabeculectomy (TE). The purpose of this study was to compare visual acuity and refractive changes after TE or XEN microstent implantation (XEN) in primary open-angle glaucoma (POAG) or pseudoexfoliation glaucoma (PEX) cases naïve to prior glaucoma surgery over a 24-month follow-up period. We analyzed 149 consecutive glaucoma patients who received either TE or XEN because of medically uncontrollable POAG or PEX. Intraocular pressure (IOP), IOP-lowering medication use, subjective and objective refraction and best-corrected visual acuity were evaluated. In addition, surgically induced astigmatism (SIA) was calculated and compared using the vector analysis method described by Jaffe and Clayman. A total of 93 eyes (85 POAG; 8 PEX) were treated with TE and 56 eyes (50 POAG; 6 PEX) with XEN. After 24 months, the mean IOP and number of IOP-lowering medications used decreased significantly after TE (p < 0.01) and XEN (p < 0.01). In the TE group, mean best-corrected visual acuity (BCVA) changed from 0.16 ± 0.26 to 0.23 ± 0.28 logMAR (p < 0.01) after 24 months, while mean BCVA did not change significantly in the XEN group (preoperative: 0.40 ± 0.50 logMAR, postoperative: 0.36 ± 0.49 logMAR; p = 0.28). SIA was almost the same in both groups at the end of the 24-month follow-up period (0.75 ± 0.60 diopters after TE and 0.81 ± 0.56 diopters after XEN; p = 0.57). In addition, there was no significant correlation between SIA and the observed BCVA changes or SIA and IOP reduction 12 or 24 months after TE or XEN. Our results demonstrate that TE and XEN are effective methods for reducing IOP and IOP-lowering medication use. The SIA was nearly similar in both groups. The SIA does not seem responsible for the decreased visual acuity after TE.

XEN® implantation: an effective strategy to stop glaucoma progression despite prior minimally invasive glaucoma surgery

Purpose

The aim of this study was to evaluate whether XEN® implantation is a reasonable and safe method to lower the intraocular pressure (IOP) and amount of medication for adult primary open-angle glaucoma (POAG) over a 3-year period. The influence of the type of anesthesia, previous glaucoma surgery, and postoperative interventions on the outcome were examined.

Methods

In this retrospective study, 96 eyes were included. XEN® implantation was performed as sole procedure under general (n = 86) or local anesthesia (n = 10). IOP and number of glaucoma medication were assessed preoperatively: day 1, week 6, month 3, 6, 12, 24, and 36. Further outcome parameters were Kaplan–Meier success rates, secondary intervention, and complication rates.

Results

IOP decreased from 20.7 ± 5.1 to 12.8 ± 2.5 mmHg at the 36-month follow-up (p < 0.001) and glaucoma therapy was reduced from 3.3 ± 0.8 to 1.2 ± 1.6 (36 months, p < 0.001). Transient postoperative hypotony was documented in 26 eyes (27.1%). General anesthesia resulted in a significant improvement of the survival rate compared to local anesthesia (77% vs. 50%, p = 0.044). Prior iStent inject®, Trabectome®, or SLT laser had no significant impact, such as filter bleb revision. The number of postoperative needlings had a significantly negative influence (p = 0.012).

Conclusion

XEN® implantation effectively and significantly lowers the IOP and number of glaucoma therapy in POAG in the 36-month follow-up with a favorable profile of side effects and few complications. In case of IOP, general anesthesia has a significant positive influence on the survival rate, whereas prior SLT or MIGS does not have significant impact.

Bleb-related Porcine Lymphatic Outflow is Greater from Subconjunctival compared to Subtenon Blebs

Aim

Understanding the mechanism of fluid outflow by comparing the subconjunctival and subtenon spaces can lead to improved ocular therapeutics. The purpose of the current study is to evaluate subconjunctival vs subtenon lymphatic outflow by creating tracer-filled blebs in each location.

Methods

Porcine (n = 20) eyes received subconjunctival or subtenon injection(s) of fixable and fluorescent dextrans. Blebs were angiographically imaged using a Heidelberg Spectralis ([Heidelberg Retina Angiograph] HRA + OCT; Heidelberg Engineering) and bleb-related lymphatic outflow pathways were counted. Optical coherence tomography (OCT) imaging of these pathways was used to assess structural lumens and the presence of valve-like structures. Furthermore, a comparison between tracer injection locations (superior/inferior/temporal/nasal) was made. Histologic analyses for subconjunctival and subtenon outflow pathways were performed, to confirm tracer co-localization with molecular lymphatic markers.

Results

Subconjunctival blebs demonstrated a greater number of lymphatic outflow pathways compared to subtenon blebs in every quadrant [superior: 6.10 ± 1.18 (subconjunctival) vs 0.50 ± 0.27 (subtenon); temporal: 2.30 ± 0.40 vs 0.10 ± 0.10; nasal: 5.30 ± 0.60 vs 0.30 ± 0.21; inferior: 6.00 ±1.29 vs 0.1 ± 0.1; all comparisons p < 0.001]. For subconjunctival blebs, the temporal quadrant showed fewer lymphatic outflow pathways compared to the nasal side (p = 0.005).

Discussion

Subconjunctival blebs accessed greater lymphatic outflow compared to subtenon blebs. Furthermore, regional differences existed, with fewer lymphatic vessels temporal than at the other locations.

Clinical significance

Aqueous humor drainage after glaucoma surgery is incompletely understood. The present manuscript adds to our understanding of how lymphatics might influence filtration bleb function.

How to cite this article

Lee JY, Strohmaier CA, Akiyama G, et al. Bleb-related Porcine Lymphatic Outflow Is Greater from Subconjunctival compared to Subtenon Blebs. J Curr Glaucoma Pract 2022;16(3):144-151.

Ab Interno XEN Gel Stent Implantation in Eyes with Previous Tube Shunt Surgery

Purpose

After tube shunt surgery, many factors may contribute to insufficient filtration over time, prompting further intervention to achieve optimal intraocular pressure (IOP) control. This study explores whether ab interno XEN gel stent implantation could be a viable approach in eyes that need further IOP reduction after tube shunt surgery.

Methods

This is a retrospective, single-surgeon case series on ab interno XEN45 gel stent implantation in eyes that had previous tube shunt surgery. Main outcome measures were IOP and number of glaucoma medications at the pre-operative visit, post-operative week (POW) 1, and post-operative month (POM) 1, 3, 6, and 12. Adverse events and further interventions were noted. Surgery outcome was qualified as absolute success (IOP ≤ 18mmHg or ≥ 20% IOP reduction without glaucoma medications), qualified success (IOP ≤ 18mmHg or ≥ 20% IOP reduction with glaucoma medications), or failure (IOP > 18mmHg and < 20% IOP reduction with maximum tolerated glaucoma medications).

Results

7 eyes from 6 patients were included in this study. IOP was reduced from 23.9 ± 5.3 mmHg (mean ± standard deviation) pre-operatively to 14.0 ± 5.3 mmHg at POM12 (p < 0.05). Number of glaucoma medications was reduced from 4.3 ± 1.3 pre-operatively to 1.6 ± 1.6 at POM12 (p < 0.05). Hypotony and choroidal effusion were noted in one case which resolved before POM1. Bleb needling was required in 3 of the 7 eyes (43%), with one eye requiring needling twice. By POM12, 2 of 7 eyes (29%) achieved absolute success, 4 eyes (57%) qualified success, and 1 eye (14%) was qualified as failure.

Conclusion

Ab interno XEN gel stent can effectively reduce IOP and number of glaucoma medications after failed tube shunt surgery. Nonetheless, further interventions such as bleb needling may still be required to optimize IOP control.

Two-year Outcomes of XEN Implantation with Minimal Bleb Needling

Aim

Our study aims to report the 2 years outcomes of the XEN implant in a single unit, single surgeon setting with minimal bleb needling.

Methods

A retrospective cohort study was conducted. Inclusion criteria were patients who underwent implantation with a XEN device between May 2016 and December 2017. This included patients who underwent both combined phacoemulsification and intraocular lens implantation alongside XEN implantation and those who underwent XEN implantation alone. Data gathered included basic demographic data, best-corrected visual acuity (LogMAR), intraocular pressure (IOP) in mm Hg, mean deviation from their visual field test, and the number of IOP-lowering medications they were on. This information was recorded for their preoperative visit, and then at 6, 12, 18 and 24 months postoperatively. The primary outcome assessed was a complete success when the patient was without glaucoma medications and had an IOP of 18 mm Hg or less, but more importantly, this also had to equate to a 20% reduction in IOP compared to baseline. Qualified success was defined as the same change in IOP but with medications. Surgical failure is defined as those who required additional glaucoma surgery or those who did not obtain an IOP of 18 mm Hg alongside a 20% reduction in IOP compared to baseline.

Results

At 24 months follow-up 82.5% of patients were surgical successes. Complete surgical success was achieved in 27% of patients. Qualified surgical success was achieved in 55.6% of patients. Subgroup analysis of those undergoing XEN implantation on its own and those combined with phacoemulsification + IOL were similar. The rate of bleb needling was low at 4.5%. Complication rates were acceptable at 9.5%.

Conclusion

It is possible to get good IOP control with minimal postoperative bleb needling in patients who have undergone XEN implantation. Similar success rates are found in those undergoing combined procedures.

Clinical Significance

Bleb needling carries its own risks. Minimizing the number of bleb needling allows procedures to be reserved at a later date. Furthermore, our study shows that success rates are not affected by doing a combined procedure with phacoemulsification.

How to cite this article

Ali ZC, Moshin N, Hakim MT, et al. Two-year Outcomes of XEN Implantation with Minimal Bleb Needling. J Curr Glaucoma Pract 2022;16(2):79-83.

The efficacy of XEN gel stent implantation in glaucoma: a systematic review and meta-analysis

Background

Xen is a device for minimally invasive glaucoma surgery, and is used to treat POAG, pseudoexfoliative or pigmentary glaucoma, as well as refractory glaucoma. The efficacy of XEN in treating glaucoma remains to be confirmed and clarified. Hence, we conducted a systematic review and meta-analysis to examine the efficacy and associated complication of XEN implantations.

Methods

We conducted a literature search in PubMed, EMBASE, the Cochrane Library of Systematic Reviews, Web of Science, China National Knowledge Infrastructure, WanFang and SinoMed databases to identify studies, published before May 15, 2021, which evaluated XEN in glaucoma, and parameters for measurements included intra-ocular pressure (IOP), number of anti-glaucoma medications (NOAM), and bleb needling rate. We compared the measurements of XEN-only procedure between phaco-XEN and trabeculectomy, and we also did sub-analysis based on time points, glaucoma types, ethnics, etc. Sensitivity analyses and publication bias were conducted for evaluating bias.This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA 2020) reporting guideline.

Results

We identified 78 eligible studies, analysis revealed obvious IOP reduction after XEN stent implantation (SMD: 1.69, 95% CI 1.52 to 1.86, p value < 0.001) and NOAM reduction (SMD: 2.11, 95% CI 1.84 to 2.38, p value < 0.001). Sub-analysis showed no significant difference with respect to time points, ethnicities, and economic status. No significant difference was found between XEN treatment effect on POAG and PEXG eyes and between pseudo-phakic and phakic eyes. Also no significant difference was found between XEN and phaco-XEN surgery in terms of IOP after surgery (SMD: -0.01, 95% CI -0.09 to 0.08, p value 0.894). However, NOAM (after publication bias correction) and bleb needling rate (RR: 1.45, 95% CI 1.06to 1.99, p value 0.019) were lower in phaco-XEN group compared to XEN only group. Compared to trabeculectomy, XEN implantation had similar after-surgery IOP, however bleb needling rate (RR: 2.42, 95% CI 1.33 to 4.43, p value 0.004) was higher.

Conclusion

Our results confirmed that XEN is effective in lowering both IOP and NOAM till 48 months after surgery. It is noteworthy that XEN implantation leads to higher needling rate, compared to phaco-XEN or trabeculectomy. Further research, studying complications of XEN on non-European ethnicities, especially on Asian, are in urgent need before XEN is widely applied.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02502-y.

Comparison of Clinical Outcomes Following Gel Stent Implantation via Ab-Externo and Ab-Interno Approaches in Patients with Refractory Glaucoma

Purpose

To compare clinical outcomes following gel stent implantation via ab externo and ab interno approaches in patients with refractory glaucoma.

Patients and Methods

This retrospective study included 203 eyes of 185 patients aged ≥45 years who underwent Xen gel stent implantation as a standalone procedure for medically uncontrolled glaucoma (intraocular pressure (IOP) ≥18 mmHg) despite maximum tolerable IOP-lowering medications. One hundred and five eyes underwent gel stent implantation via ab interno approach and 98 via ab externo. Patients with prior conjunctival-incisional glaucoma or cataract surgery were also included. Study parameters were reduction in IOP and number of IOP-lowering medications from baseline to 3, 6, 9 and 12 months postoperatively.

Results

There were no statistically significant differences in the age, sex, preoperative IOP, number of IOP-lowering medications or cup–disc ratio between the ab interno and ab externo groups at baseline (p > 0.05). At all postoperative time points, mean IOP and percentage reduction from baseline were comparable in both groups (p > 0.05) except at postoperative 6 months when the outcomes were significantly better (p < 0.05) in the ab externo group. The rate of postoperative procedures (5-Fluorouracil injections and bleb needling), the incidence of numerical or clinical hypotony and adverse events were comparable in both groups (p > 0.05). The mean number of IOP-lowering medications was comparable in both groups at all time points.

Conclusion

The Xen gel stent, whether implanted ab interno or ab externo, is effective in reducing IOP and dependence on topical medications in eyes with refractory glaucoma. The stent may be used in both phakic and pseudophakic patients and is a reasonable option for patients with prior failed trabeculectomy.

Outcomes of XEN 63 Device at 18-Month Follow-Up in Glaucoma Patients: A Two-Center Retrospective Study

Background: Glaucoma surgery has significantly evolved over the last years. This paper aims to evaluate the midterm clinical outcomes of the XEN63 device in a real-world scenario. Methods: A retrospective clinical study was conducted on consecutive patients who underwent an XEN63 implant insertion, either alone or in combination with phacoemulsification. The primary endpoint was the mean intraocular pressure (IOP) at the month 18 visit. Results: Twenty-three eyes (23 patients) were included in the analysis. The preoperative IOP was significantly lowered from 27.0 ± 7.8 mmHg to 14.1 ± 3.4 mmHg at month 18 (p < 0.0001). At month 18, 14 (77.8%) and 11 (61.1%) eyes had an IOP ≤ 16 mmHg and ≤ 14 mmHg, respectively, without ocular hypotensive medication. The mean number of ocular hypotensive medication taken was significantly reduced from 2.3 ± 0.9 drugs at baseline to 1.0 ± 1.4 drugs at month 18 (p = 0.0020). Four (17.4%) eyes had hypotony at postoperative day 1, which was successfully resolved without sequelae. Four (17.4%) eyes underwent a needling procedure and four (17.4%) eyes underwent additional surgeries. Conclusions: The XEN63, either alone or in combination with cataract surgery, significantly lowered the IOP and reduced the need for ocular hypotensive drugs over a period of 18 months.

Short-term Efficacy and Safety of Open Conjunctiva ab Externo XEN45 Gel Stent Implantation in Glaucoma Patients

PRCIS

We examined the safety and efficacy of the open conjunctiva ab externo approach for XEN45 gel stent implantation. There was a significant reduction in intraocular pressure and number of glaucoma medications at 12 months follow-up.

PURPOSE

This study aims to determine the safety and efficacy of the open conjunctiva ab externo approach to XEN45 stent implantation.

METHODS

Retrospective chart review of all patients between July 2018 and March 2020 who underwent XEN implantation. IOP and number of glaucoma medications were measured at the preoperative, 1 day, 1 week, 1-, 3-, 6-, and 12 months postoperative appointments. The primary outcome of this study is the number of cases achieving complete success at 12 months postoperative.

RESULTS

44 eyes of 44 patients were included. Mean preoperative IOP was 26.2±8.7 mmHg on 3.2±0.7 IOP-lowering medications. At 12 months postoperative, mean IOP was 18.9±9.1 mmHg (n=35, P<0.0001; mean reduction of 27.9%) on 0.9±1.4 (n=35, P<0.0001) IOP-lowering medications. Postoperative needling was performed in 5 cases (11.4%). Of the 35 cases with a postoperative visit at 12 months, complete success was achieved in 14 cases (40.0%) and qualified success in 3 cases (8.6%). Eighteen cases (51.4%) were recorded as failures at 12 months, comprised of 4 cases requiring reoperation for glaucoma (2 XEN implants, 1 trabeculectomy, and 1 Baerveldt implant), and 14 cases that did not meet the IOP-lowering criteria for success. During the postoperative course, there was one case of self-limited hypotony, two self-resolving choroidal effusions, and three cases of bleb leakage.

CONCLUSIONS

The open conjunctiva ab externo approach to XEN45 implantation achieved successful levels of IOP reduction in 48.6% of glaucoma cases within the first year. The most common adverse events included the need for additional glaucoma surgery (excluding needling procedures), transient hypotony, and bleb leak.

Compatibility and Durability of the Gel Stent Material

INTRODUCTION

The XEN Gel Stent (AbbVie Pharmaceuticals) is a device made from Gelatin; a well-known material in the medical field that is firm enough to hold its shape and soft enough to conform to tissues and reduce the risk of erosion. The Gel Stent creates a permanent outflow connection between the anterior chamber and subconjunctival space.

AREAS COVERED

Validation testing done on the Gel Stent to evaluate biocompatibility and durability of the material as well as real-world experience are included and discussed in this paper.

EXPERT OPINION

Correlating the results of the preclinical testing, study outcomes available in the published literature, and the surgeons' experiences, the device and materials have shown to have an acceptable biocompatibility and durability profile, with a stable, nondegradable, and permanent implant.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Two-Year Outcome of Surgery in Glaucoma Patients

PURPOSE

To evaluate the 2-year surgical treatment outcome in glaucoma patients.

METHODS

A retrospective, single-center, interventional study was performed on 160 eyes of 125 patients suffering glaucoma, including POAG (82 eyes), pseudoexfoliation (PEX) (59 eyes), pigment dispersion (8 eyes), and secondary glaucoma (2 eyes). Eyes with uncontrolled intraocular pressure (IOP) or signs of glaucoma progression despite medical treatment were included to undergo either trabeculectomy (TE), XEN implantation, combined TE with phacoemulsification (TE + IOL), or XEN implantation with phacoemulsification surgery (XEN + IOL). Primary efficacy outcome was the mean IOP reduction. Secondary outcome was the mean reduction in the number of medications. The data were compared at baseline vs.1 day, 1 week, and 1, 3, 6, 12, and 24 months following surgery. For statistical evaluation, ANOVA-based linear mixed-effects models were performed with SPSS.

RESULTS

The mean IOP reduction in a 2-year follow-up was 30.31% (22.17 vs. 15.45 mmHg, p < 0.001). The mean number of antiglaucoma medications was reduced from 2.87 to 0.58 (p = 0.001), where TE alone or combined surgeries seemed to be more effective than isolated XEN surgery. Transient IOP hypotony on the first postoperative day occurred in PEX patients following TE surgery (p = 0.024). At 6 months, PEX patients with isolated XEN surgery showed a transient IOP increase, whereas those after combined TE + IOL surgery showed the lowest IOP within the PEX group compared to other glaucoma patients (p < 0.026).

CONCLUSIONS

After 2 years, all performed glaucoma surgeries achieved a significant reduction in IOP and the number of antiglaucoma medications.

Ultrastructural analysis of explanted CyPass microstents and correlation with clinical findings

Purpose

The purpose of this study was to obtain insight into cellular processes after CyPass microstent implantation into the supraciliary space. With this knowledge, we expected to find some reason for surgical failure.

Methods

Nine CyPass microstents of 8 patients with primary open-angle glaucoma (n = 1), pseudoexfoliation glaucoma (n = 5), uveitic glaucoma (n = 1), and posttraumatic open-angle glaucoma (n = 1) were explanted due to recurrence of IOP elevation, corneal decompensation, or persistent hypotony. The explants were processed for light and transmission electron microscopy.

Results

Fibrotic material, consisting of collagen fibrils, microfibrils, pseudoexfoliation fibrils produced by activated fibroblasts, was detected in the stent lumen of 4/5 pseudoexfoliation glaucoma patients and also in posttraumatic open-angle glaucoma. Fibrotic material was also present on the outer surface and within fenestrations of the majority of stents. Complete absence of fibrotic reaction was noticed in 3 of 9 microstents.

Conclusion

Although MIGS is known to be less invasive than conventional surgery, implants placed in the suprachoroidal space may be adversely affected by a fibrotic tissue reaction resulting in implant failure. Understanding mechanisms and risk factors leading to fibrotic scarring following antiglaucomatous surgery may help to develop novel strategies that improve surgical outcome.

Does mitomycin-C concentration have any influence on XEN45 gel stent outcomes in a real-world setting?

BACKGROUND

To compare the effectiveness and safety of XEN45 implanted with mitomycin-C (MMC) 0.01% versus (vs) XEN45 implanted with MMC 0.02%.

METHODS

Retrospective and single-center study conducted on consecutive patients with open-angle glaucoma or ocular hypertension who underwent XEN45-implant, either alone or in combination with cataract surgery. The primary end-point was the mean change in intraocular pressure (IOP) from baseline to the last follow-up visit.

RESULTS

Fifty-five patients (63 eyes) were included. Thirty-seven (58.7%) eyes underwent surgery with MMC 0.01% and 26 (41.3%) ones with MMC 0.02%. In the overall study sample, the mean (standard error) IOP was significantly lowered from 17.6 (0.7) mm Hg at baseline to 12.6 (0.3) mm Hg at month 12. The IOP was significantly lowered from 17.3 (15.4 to 19.2) mm Hg and 17.9 (16.1 to 17.8) mm Hg at baseline to 12.3 (11.3 to 13.3) mm Hg and 13.1 (12.3 to 13.9) mm Hg at month 12 in the MMC 0.01% and MMC 0.02% groups, respectively; p < 0.0001 each. The mean number of ocular-hypotensive medications significantly decreased from 2.1 (1.9 to 2.3) at baseline to 0.2 (0.04 to 0.3) at month 12, p < 0.0001, with no significant differences between MMC 0.01% and MMC 0.02% groups, p = 0.5181. At month 12, 50 (80.6%) eyes had functioning blebs. Regarding safety, 18 (28.6%) eyes have experience adverse events.

CONCLUSION

XEN45, either alone or in combination with cataract surgery, showed a good effectiveness and safety profile. MMC dose had no influence on the IOP lowering, which may support the use of the lowest dose.

Impact of Primary Needling on the XEN Implant Clinical Outcomes: A Real-Life Retrospective Study

Purpose

To assess the effectiveness and safety of primary-needling in eyes who underwent a XEN45 implant.

Methods

Retrospective and single center study. Consecutive patients with early-to-moderate open-angle glaucoma (OAG) or ocular hypertension, who underwent XEN45 surgery, either alone or combined with phacoemulsification, and had at least a valid 12-month post-operative visit, were included in the study. Primary needling was performed by using a 30-gauge needle without viscoelastic. Subjects were divided in two groups: Eyes who underwent XEN+primary-needling (needling) and those who underwent XEN without primary-needling (no-needling). The primary end-point was the mean change in IOP from baseline to the last follow-up visit.

Results

Sixty-three eyes, 19 (30.2%) in the needling group and 44 (69.8%) in the no-needling one, were included in the study. There were not significant differences in mean IOP lowering between needling and no-needling groups at month-12 (mean difference −2.5±5.3 mm Hg, p=0.0926). No significant differences in mean reduction of ocular-hypotensive medications were observed between needling and no-needling groups, p=0.8690. At month-12, 50 (80.6%) had blebs considered as functioning, with no difference between groups, p = 0.5631. At month-12, 59 (93.7%) eyes were classified as success, with no significant differences between needling (17/19) and no-needling (42/44) groups, p=0.3754. Secondary needling was performed in 8 (12.7%) eyes, without differences between groups (p=0.6333).

Conclusion

Primary needling, at the time of surgery, was a safe procedure in OAG patients who underwent a XEN implant, although it was not associated with a lower postoperative IOP or less ocular hypotensive medications.

The Outcomes of XEN Gel Stent Implantation: A Systematic Review and Meta-Analysis

Purpose

XEN gel stents are used for the treatment of open-angle glaucoma (OAG), including primary and secondary glaucoma that are uncontrolled by previous medical therapy and cases with previous failed surgery. Our aim was to systematically review of the clinical data of currently published ab-interno XEN gel stents with an emphasis on intraocular pressure (IOP), antiglaucoma medication outcomes, and safety profiles.

Methods

We analyzed all of the publications (MEDLINE, EMBASE, Cochrane Library) on the ab-interno XEN gel stent to evaluate the reduction in IOP and antiglaucoma medications following the procedure. The primary outcomes measured for the meta-analysis were reduction in IOP and anti-glaucoma medications. The secondary outcome were adverse events. For each study, we used a random effects analysis model to calculate the mean difference and 95% confidence intervals for the continuous results (reduction in IOP and antiglaucoma medications) using the inverse variance statistical method.

Results

Five hundred twenty-seven articles were checked and 56 studies were found to be relevant with a total of 4,410 eyes. There was a significant reduction in IOP as well as in the number of medications required in patients treated with ab-interno XEN implant either alone or combined with cataract surgery. This new treatment for various types of glaucoma reduced the IOP by 35% to a final average close to 15 mmHg. This reduction was accompanied by a decrease in the number of antiglaucoma medications in all the studies, approximately 2 classes of medication at the price of more needlings. The overall complete success rate was 21.0–70.8% after 2 years using strict criteria originally designed to record success rate in filtration surgery. The incidence of complications vision-threatening was low at <1%.

Conclusions

XEN gel stent was effective and safe for primary and secondary OAG. Further studies should be performed to investigate the impact of ethnicity on the success and failure rate after XEN implantation.

Long-term results of the safety and effectiveness of a novel microshunt in Japanese patients with primary open-angle glaucoma

PURPOSE

To evaluate the long-term safety and effectiveness of the Preserflo MicroShunt in Japanese primary open-angle glaucoma (POAG) patients.

STUDY DESIGN

Single-site, nonrandomized observational study.

PATIENTS AND METHODS

Eight eyes of 7 POAG patients were included. The surgical complications and interventions were monitored. The preoperative and postoperative intraocular pressures (IOPs), numbers of antiglaucoma medications, logarithm of the minimum angle of resolution visual acuity (VA), mean deviation (MD) slope, and corneal endothelial cell density (CECD) were compared retrospectively.

RESULTS

The mean follow-up period was 68.9 months (range, 48-76 months). The baseline IOP of 17.9 ± 3.5 mmHg and the number of glaucoma medications of 3.5 ± 0.5 were significantly reduced at subsequent follow-up visits. At 1, 2, 3, 4, 5, and 6 years postoperatively, the IOPs were 13.8 ± 2.9, 12.8 ± 2.3, 12.1 ± 3.2, 12.6 ± 2.5, 12.3 ± 1.0, and 13.5 ± 3.1 mmHg, respectively, with the use of 1.6 ± 1.4, 1.6 ± 1.6, 1.5 ± 1.4, 1.5 ± 1.4, 1.9 ± 1.3, and 2.0 ± 1.1 medications. Postoperative transient hyphema occurred in 1 eye. Postoperative needling was required in 5 eyes, 12 times in total. No eyes showed significant VA decline, except for 1 eye with a severe central visual field defect that existed preoperatively. The preoperative MD slope of - 1.6 ± 1.2 dB/year improved significantly, to - 0.3 ± 0.2 dB/year (P = 0.023), postoperatively. The baseline CECD decreased from 2595 ± 292 to 2478.4 ± 255 postoperatively.

CONCLUSION

The microshunt surgical procedure is safe and effective for Japanese POAG patients.

Multiple XEN Gel Stents for Refractory Pediatric Glaucoma

Although trabeculotomy and goniotomy are currently the mainstay of surgical management for congenital glaucoma, XEN Gel Stent (Allergan) implantation and other microinvasive glaucoma surgery technologies may offer the advantage of having a lower risk of postoperative complications than conventional techniques. A 10-year-old boy presented with aphakic glaucoma in his left eye secondary to previous cataract surgery. Intraocular pressure (IOP) in the left eye at initial presentation was 31 mm Hg with maximal tolerated medical therapy. Surgical history included tube shunt, shunt revision, and subsequent shunt removal. Shunt surgery and revision had been unsuccessful at achieving target IOP. The patient underwent two treatments of micro-pulse transscleral laser therapy that failed to achieve target IOP. At this time, an open conjunctiva ab externo superior XEN Gel Stent (Allergan) was implanted. Within 1 month of surgery, conjunctival dehiscence and contraction occurred. Following this, ab interno inferonasal air-ophthalmic viscosurgical device XEN Gel Stent implantation was performed. In the 6 months following the second XEN Gel Stent, IOP in the left eye was stable at 6 to 8 mm Hg. This report describes the effective use of a XEN Gel Stent implant in the management of congenital glaucoma, while also highlighting a complication. Further studies are required to determine the comparative outcomes of this technique with conventional surgical management. [J Pediatr Ophthalmol Strabismus. 2022;59(1):e11-e14.].

Preliminary results of Preserflo Microshunt versus Preserflo Microshunt and Ologen implantation

PURPOSE

To report preliminary 6-month results on the use of the Preserflo Microshunt implant with and without Ologen in 50 pseudophakic eyes with moderate to advanced primary open-angle glaucoma (POAG).

METHODS

Fifty pseudophakic eyes underwent ab externo Preserflo Microshunt implantation. Data was gathered retrospectively and two groups were then created, group A with application of MMC 0.2 mg/ml and group B with MMC 0.2 mg/ml and Ologen collagen matrix (OCM) implantation. Absolute success was regarded as the percentage of eyes achieving: a) 5 ≤ intraocular pressure (IOP) ≤ 13 mmHg, b) 5 ≤ IOP ≤ 16 mmHg, and c) 5 ≤ IOP ≤ 21 mmHg without additional medication or surgery and qualified success was regarded as the percentage of eyes achieving a) IOP ≤ 13 mmHg, b) IOP ≤ 16 mmHg, and c) IOP ≤ 21 mmHg with or without medication. Evaluation was performed using a log-rank Kaplan-Meier test. A scatterplot analysis presented the treatment effect data of all eyes with a minimum of 20% IOP reduction per case. Failure was defined as requiring additional surgery, IOP greater than 21 mmHg with or without medication and failure to reach 20% IOP reduction.

RESULTS

Mean postoperative IOP was significantly lower in both groups. IOP decreased by 49.06% in group A and by 53.01% in group B at 6 months (P < 0.88), respectively. Medication use was lower in both groups (Wilcoxon test, P < 0.001). The absolute and qualified success rates were not statistically significant between the groups (all P > 0.05). Cumulative IOP results per case were not statistically different in group A compared with group B. One revision surgery in group A (4% failure rate) and three in group B (12% failure rate) were performed.

CONCLUSIONS

Both groups showed equal results in terms of cumulative and mean IOP reduction, medication reduction as well as in absolute and qualified success rates. No significant difference was found in any parameters tested between Preserflo Microshunt with MMC 0.2 mg/ml and with or without OCM implantation at 6 months. Long-term follow-up is required to further evaluate this data.

Impact of failed ab-interno trabeculectomy (trabectome) on subsequent XEN45 gel stent implantation in pseudophakic eyes

PURPOSE

To determine the impact of failed ab-interno trabeculectomy on the postoperative outcome of subsequent XEN45 gel stent (Allergan, CA, USA) implantation in pseudophakic eyes.

METHODS

In this retrospective single-center study, we included 60 pseudophakic eyes from 60 participants who underwent XEN45 gel stent implantation. Thirty eyes each underwent primary stent implantation (control group) or had previously undergone a failed ab-interno trabeculectomy (trabectome group). The groups were matched at a 1:1 ratio based on the following criteria: preoperative and maximum Intraocular pressure (IOP), preoperative medication score, cup/disk-ratio, follow-up time, best-corrected visual acuity at baseline, age, and the proportion of patients classified as primary open angle glaucoma or exfoliation glaucoma. We defined a successful surgery by the following three scores: an IOP reduction > 20% and IOP at the longest follow-up < 21 mmHg (Score A) or < 18 mmHg (Score B) or IOP ≤ 15 mmHg and an IOP reduction ≥ 40% (Score C). One open conjunctival revision was allowed in all scores, and a repeat surgery was considered a failure.

RESULTS

Following an average follow-up period of 22 ± 12 months, we observed a mean IOP reduction of 38%, from 23.5 ± 5.2-14.5 ± 5.0 mmHg. Comparative analyses between the groups did not reveal a significant difference in the postoperative IOP, postoperative medication score, side effects, revision rate, repeat surgery rate, or success rate.

CONCLUSIONS

Trabectome is a viable first-line procedure for medically uncontrolled glaucoma before filtering ab-interno microstent surgery is considered.

Influence of Mitomycin C on the Therapeutic Success of Stand-Alone Xen45 Gel Stents and Its Combination with Cataract Surgery in Open-Angle Glaucoma Patients

PURPOSE

Minimally invasive glaucoma surgery (MIGS), like Xen45 gel stents, is known as effective therapy in lowering intraocular pressure (IOP); however, fibrotic reactions are a common problem in postoperative management. It was the aim of this study to investigate the therapeutic success of Xen45 gel stents as a stand-alone technique (Xen) and combined with cataract surgery (XenPhaco), and with antimetabolites (mitomycin C, MMC) in open-angle glaucoma patients.

METHODS

Retrospective analysis was performed of 199 eyes of 177 glaucoma patients of the Department of Ophthalmology, University of Erlangen Nürnberg, and from the Erlangen Glaucoma Registry (NCT00494923; ISSN 2191-5008, CS-2011) who underwent implantation of a Xen45 gel stent. Therapeutic success was defined as IOP reduction of ≥ 20% on the same or less anti-glaucomatous medication after 12 months compared to preoperative and without any additional glaucoma-related surgery (except bleb needling). IOP reduction, reduction in local anti-glaucomatous eye drops, and intra- and postoperative complications were monitored.

RESULTS

Stand-alone Xen45 gel stent: therapeutic success was reached in 39% (-MMC) and 55% (+MMC). Failure rate was 61% (-MMC) and 45% (+MMC). XenPhaco: therapeutic success was achieved in 57% (-MMC) and 46% (+MMC). Failure rate was 43% (-MMC) and 54% (+MMC). Data were not different for group and subgroup analyses (p > 0.05).

CONCLUSIONS

The use of MMC seemed to increase the therapeutic success rate after stand-alone Xen45 gel stent implantation and combined with cataract surgery, yet statistical significant was not reached.