Double implantation of Xen 45 gel stent in primary open-angle glaucoma: a pilot study.

PURPOSE: To describe the outcomes of double implantation of Xen 45 Gel Stent (Xen) using an ab externo approach with closed conjunctiva. METHODS: Retrospective single-centre case series of primary open-angle glaucoma patients with at least six months of follow-up after implantation of a second Xen in the same eye via ab externo technique without conjunctival opening. RESULTS: Eight pseudophakic eyes of 8 patients were included. Intraocular pressure (IOP) dropped from 30 ± 2.6 mmHg pre-operatively to 22.4 ± 2.3 mmHg one month after the first Xen implant (mean difference: -7.6 mmHg [95% confidence interval: -9.4, -5.9 mmHg], p = 0.0092). A second Xen was then implanted to achieve the target IOP. The procedure showed no significant intraoperative or postoperative complications. The IOP dropped to 16.1 ± 2.7 mmHg six months following this second implant (mean difference: -6.3 mmHg [95% confidence interval: -7.2, -5.3 mmHg], p = 0.0183); however, 3 patients needed medical therapy to further reduce the IOP towards the target value. CONCLUSION: Sequential implantation of two Xen 45 Gel Stents using an ab externo approach with closed conjunctiva appears a promising procedure that showed a favorable safety and efficacy profile in this small case series. This pilot data might pave the way for further studies to evaluate the safety and efficacy of the procedure.

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.

Posture-induced changes in intraocular pressure after ab externo XEN45 gel-stent implantation in patients with primary open-angle glaucoma.

BACKGROUND: To investigate posture-induced changes in intraocular pressure (IOP) after ab externo XEN45 Gel-Stent implantation in patients with medically uncontrolled primary open-angle glaucoma (POAG). METHODS: This prospective study included thirty-two eyes with POAG that underwent XEN45 Gel-Stent implantation as a standalone procedure using an ab externo approach at Chonnam National University Hospital. IOP was measured sequentially in the sitting position, supine position, and lateral decubitus position (LDP) before and at 1, 2, 3, and 6 months after surgery using an iCare IC200 rebound tonometer. In the LDP, the eye with XEN45 Gel-Stent implantation was in the dependent position. RESULTS: IOP at each position was significantly reduced after XEN45 Gel-Stent implantation. Posture-induced changes in IOP were maintained during the follow-up. The range of postural IOP changes was reduced at 1 month; however, no significant change was observed after that point compared with baseline levels. CONCLUSIONS: A XEN45 Gel-Stent inserted using the ab externo approach can reduce IOP in various body positions, but seems to have limited effects on posture-induced changes in IOP in patients with POAG.

Standalone XEN45 Gel Stent implantation versus combined XEN45-phacoemulsification in the treatment of open angle glaucoma-a systematic review and meta-analysis.

PURPOSE: The XEN45 Gel Stent is currently the only FDA-approved sub-conjunctival minimally invasive glaucoma surgery (MIGS) procedure. It has been used worldwide either as a standalone implantation procedure or in combination with phacoemulsification surgery. Concomitant phacoemulsification is understood to influence outcomes of traditional subconjunctival filtering surgery. However, the comparative efficacy between standalone XEN45 Gel Sent implantation ("Standalone XEN45") and combined XEN-phacoemulsification surgery ("XEN45-Phaco") remains unclear. This study aims to appraise current literature to compare the efficacy of Standalone XEN45 and XEN45-Phaco in open-angle glaucoma. METHODS: A comprehensive search of PubMed, CINAHL, CENTRAL databases was performed with the terms "Xen surgery" followed by selective vetting. Pilot, cohort, observational studies and randomised controlled trials that included at least 10 patients undergoing either Standalone XEN45 or XEN45-Phaco surgeries for the treatment of open-angle glaucoma were deemed eligible for inclusion after independent assessment by 2 authors. The search workflow was reported according to the PRISMA guidelines. Data was pooled using random-effects model. A meta-analysis of continuous outcome and proportions was performed using the meta routine in R v3.2.1. RESULTS: Ten studies were included. There was a statistically significant difference in IOP reduction favouring Standalone XEN45 at post-operative day 1, week 1, months 1, 3 and 6. There was a statistically significant difference in decrease in IOP-lowering medications favouring Standalone XEN45 at post-operative week 1 and month 1. CONCLUSION: Standalone XEN45 has superior IOP-lowering outcomes compared to XEN45-Phaco in the early post-operative period, up to 6 months after surgery.

Medium-term clinical outcomes following Xen45 device implantation.

PURPOSE: To evaluate medium-term clinical outcomes with microstent XEN® 45 Gel Stent (Allergan Dublin, Ireland) for treatment of primary open-angle glaucoma (POAG). MATERIAL AND METHODS: This is a retrospective, descriptive and observational study involving 93 eyes from 63 patients who had undergone POAG surgery with a XEN® 45 Gel Stent implantation and had been followed up and controlled between 12 and 36 months. RESULTS: IOP dropped from 18.23 ± 5.00 mmHg pre-op to 14.16 ± 2.14, 14.47 ± 2.16 and 14.63 ± 1.91 at 1, 2 and 3 years after surgery (p = 0.000, 0.000 and 0.001) consecutively. Mean number of medications dropped from 1.87 ± 0.94 preoperatively to 0.31 ± 0.69, 0.34 ± 0.63 and 1.00 ± 0.88 (p = 0.000, 0.000 and 0.017) at 12, 24 and 36 months. Mean visual field deviation values never turned out to be significant for any of the follow-up visit data. A total of 94.6% of the surgical procedures turned out to be complication-free. In one surgery, the procedure failed and 18 months later other device was implanted. CONCLUSION: POAG surgical procedures with XEN® 45 Gel Stent implants are a safe and effective treatment approach.

Efficacy of the XEN gel stent on intraocular pressure lowering in East Asian eyes.

PURPOSE: This study aims to evaluate the efficacy and safety of XEN45 gel stent (Allergan plc, Dublin, Ireland) in East Asian patients with glaucoma. METHODS: A retrospective study of consecutive XEN45 gel stent implantation surgeries with or without concurrent cataract surgery from May 2017 to August 2018 was performed in a single institution. The clinical charts of all cases were reviewed to examine the safety and efficacy of the implant. Primary outcome measures were intraocular pressure (IOP), number of topical glaucoma medications required, additional procedures done and adverse outcomes. All patients included were required to fulfil a minimum of three follow-up visits by post-operative month 1. RESULTS: Sixty-three eyes were included in the study. The median duration of follow-up was 6 months [interquartile range (IQR) 2-9]. Median IOP was significantly lowered from 19 mmHg (IQR 16-24) pre-operatively to 15 mmHg (IQR 11-18) at the end-of-follow-up (p < 0.001). The median number of medications was reduced from 3 (IQR 2-4) at baseline to 0 (IQR 0-2) at the end-of-follow-up (p < 0.001). 66.7% of patients were medication-free by the end of follow-up. Post-operative bleb intervention was required for 61.9% of eyes. Adverse events included post-operative hypotony requiring intervention (4.8%) and post-operative gross hyphaema (9.6%). CONCLUSION: The XEN45 gel stent when used as a sole procedure or in combination with cataract surgery in East Asian eyes is effective in the treatment of glaucoma. However, a high rate of post-operative bleb intervention appears to be required to support its efficacy.

Ab interno gel implant in patients with primary open angle glaucoma and pseudoexfoliation glaucoma.

PURPOSE: To compare efficacy and safety results of an ab interno gel implant in patients with pseudoexfoliation glaucoma (PXG) and primary open angle glaucoma (POAG). METHODS: Retrospective analysis of the medical records of 110 consecutive eyes with open angle glaucoma who had received a XEN45 gel implant between March 2014 and June 2015. Intraocular pressure course, number of glaucoma medications, the need for additional intervention (including needling) and complications were evaluated until 12 months postoperatively. RESULTS: Data of 67 eyes with POAG and 43 eyes with PXG were analyzed. At 12 months postoperatively, the mean IOP had significantly decreased by 54.0% from preoperatively 31.85 ± 8.5 mmHg to 13.99 ± 2.6 mmHg in the POAG group, (p = 0.000; Wilcoxon test), and by 55.2% from 31.63 ± 9.0 mmHg to 13.28 ± 3.1 mmHg in the PXG group (p = 0.000; Wilcoxon test). The mean number of anti-glaucoma medications had significantly decreased from 3.25 ± 0.8 at baseline to 0.3 ± 0.7 medications at 12 months postoperatively in POAG eyes (p = 0.000; Wilcoxon test), and from 3.05 ± 1.0 to 0.3 ± 0.6 medications in PXG eyes (p = 0.000; Wilcoxon test). Hypotony (IOP ≤ 6 mmHg) was observed in 2 POAG eyes (3.0%) and in 5 PXG eyes (11.7%) at 1 month but normalized in all eyes at 12 months postoperatively. Severe complications were not observed. No statistically significant differences were found between PXG eyes and POAG eyes. CONCLUSION: Our data indicate that the XEN45 gel implant provides significant and comparable reduction in IOP and anti-glaucoma medication during the one-year follow-up period in POAG as well as PXG eyes. This suggests that it may be a noteworthy alternative to traditional filtering procedures in patients with POAG and PXG respectively.

Mid-term surgical success after transscleral ab interno glaucoma gel stent implantation.

PURPOSE: To investigate the surgical success and efficacy of XEN45 implantation (XEN45 µm, AbbVie Inc., USA) with and without combined cataract surgery up to the first 5 years. METHODS: In a prospective observational monocentric trial, 192 eyes of 157 patients with open-angle glaucoma received either XEN45 implants only (solo surgery group) or combined surgery/cataract surgeries (combined surgery group). Surgical success (qualified and full success; IOP-limit: ≤12, 15, 18, 21 mmHg), time to secondary IOP-lowering procedure, IOP and number of IOP-lowering medications were analysed for 1, 2, 3, 4 and 5 years. RESULTS: Compared to baseline, IOP (24.1 ± 8.1 to 12.6 ± 2.8 mmHg, -48%, p < 0.001) and the number of IOP-lowering medications (3.0 ± 1.0 to 1.5 ± 1.2, -50%, p < 0.001) decreased significantly at 5 years. Although no differences between IOP and the number of IOP-lowering medication courses between the groups were detected at 5 years (p > 0.11), the combined procedure (63%, 37%) showed better success rates compared to the solo procedure (36%, 13%) in the definition IOP ≤18 and ≤12 mmHg (p = 0.035, 0.028). Solo XEN45 procedures had a higher rate of secondary IOP-lowering procedures compared to combined XEN45 cataract procedures (hazard ratio: 2.02, 95%CI: 1.03-3.97, p = 0.04). Twenty per cent of the eyes, including both procedures, required a secondary IOP-lowering procedure within 5 years. CONCLUSIONS: The XEN45 implant is effective in lowering IOP and the number of IOP-lowering medications in patients with open-angle glaucoma in the mid-term. Comparing XEN45 implant results with the results of trabeculectomy available in current literature, we speculate that there might be a higher surgical success rate without medications in favour of trabeculectomy.

Outcomes and Baseline Predictors of Failure in Primary Standalone Xen45 Gel Stent versus Trabeculectomy for Glaucoma.

PURPOSE: To compare safety, effectiveness, and baseline predictors of failure in standalone primary Xen45 gel stent (Xen) versus trabeculectomy (Trab) in glaucoma. DESIGN: Retrospective study. SUBJECTS: Subjects that underwent primary Xen or Trab augmented by mitomycin-C with at least 12 months follow-up. METHODS: Multinational observational study of eyes in the Fight Glaucoma Blindness international registry MAIN OUTCOME MEASURES: The primary outcome was success at 12 months defined by intraocular pressure (IOP) reduction ≥ 20% from baseline and ≤ threshold IOPs of 15, 18, and 21 mmHg with (qualified) or without (complete) medications and without secondary glaucoma surgery. Multivariable mixed effects Cox regression models were used to identify risk factors for failure in each cohort. RESULTS: A total of 701 eyes (Xen, 308; Trab, 393) of 596 subjects were included with baseline IOP being significantly higher (22.4 vs. 19.9 mmHg, P < 0.001) and baseline medications significantly lower in the Xen versus the Trab group (2.9 vs. 3.4, P < 0.001). Baseline visual field mean deviation was less severe in the Xen group (-9.47 vs. -13.04 dB, P < 0.001). The proportion of complete surgical success was significantly lower in the Xen versus Trab group across the 3 upper IOP limits at 12 months; 32% versus 52% at 15 mmHg, 37% versus 54% at 18 mmHg, and 39% versus 55% at 21 mmHg (P < 0.001). The incidence of postoperative numerical and symptomatic hypotony was lower in the Xen versus Trab group. In the Xen cohort, a higher failure rate was associated with Asian ethnicity (hazard ratio [HR], 1.97; 95% confidence interval (CI), 1.03-3.79) and use of oral acetazolamide at baseline (HR, 1.74; 95% CI, 1.13-2.70), whereas a lower failure rate was associated with diagnosis of ocular hypertension/open-angle glaucoma suspect (HR, 0.40; 95% CI, 0.20-0.82) and secondary open-angle glaucoma (HR, 0.46; 95% CI, 0.26-0.82). Exposure to prostaglandin analog was associated with greater failure in the Trab group (HR, 2.66; 95% CI, 1.18-6.01). CONCLUSIONS: There was significantly greater complete success at 12 months across all complete success definitions for Trab compared with Xen, whereas the rate of postoperative hypotony was significantly lower in the Xen group. Asian ethnicity and use of oral acetazolamide at baseline were associated with greater failure in Xen, whereas exposure to prostaglandin analog was associated with greater failure in Trab patients. Such baseline predictors of success and failure may help guide patient selection for subconjunctival minimally invasive glaucoma surgery in patients undergoing surgical intervention. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Complications Following XEN45 Gel Stent and Glaucoma Drainage Device Implantation During Glaucoma Fellowship.

Purpose XEN45 Gel Stent and glaucoma drainage device (GDD) implantation is safe and effective for glaucoma treatment and should be taught during glaucoma fellowship training. However, complications may still occur, with potentially sight-threatening consequences. The purpose of this study is to describe the management of complications following a series of XEN45 Gel Stent and GDD surgeries performed over the course of glaucoma fellowship training. Methods This is a retrospective case series of XEN45 Gel Stent surgeries performed on 16 eyes and GDD surgeries performed on seven eyes. Patient demographics, disease characteristics, and complications are reviewed. The intra- and postoperative course of five select cases with complications are described in detail. Results The most frequent complications following XEN45 implantation were transient hypotony (10 eyes, 63%), reduced visual acuity (VA) (five eyes, 31%), choroidal effusion (three eyes, 19%), hyphema (two eyes, 13%), and intraocular pressure (IOP) spike (two eyes, 13%). Thirteen eyes (81%) required bleb needling, and three eyes (19%) required XEN45 replacement. Complications following GDD implantation included hypotony (three eyes, 43%), reduced VA (two eyes, 29%), choroidal effusion (two eyes, 29%), IOP spike (two eyes, 29%), implant exposure (two eyes, 29%), and shallow anterior chamber (one eye, 14%). Three eyes (43%) required revision or explantation with a secondary glaucoma surgery. One choroidal effusion following XEN45 surgery and one following GDD surgery were hemorrhagic choroidal effusions requiring surgical drainage. Conclusion Significant and potentially sight-threatening complications may occur following XEN45 Gel Stent and GDD implantation performed over the course of fellowship training. Glaucoma fellows should be ably equipped to recognize, diagnose, and manage these complications both intra- and postoperatively.

XEN45 Implant in Medically Controlled vs. Uncontrolled Eyes-Differential IOP Changes in Real-Life Conditions.

Background: To assess intraocular pressure (IOP) changes and complications after XEN45 implants in medically controlled eyes (MCE) vs. medically uncontrolled eyes (MUE). Methods: A retrospective study, in a tertiary referral hospital, on mild-to-moderate primary open-angle glaucoma (POAG) cases under topical medication, including 32 eyes with IOP < 21 mmHg (MCE group) and 30 eyes with IOP ≥ 21 mmHg (MUE group). The success criteria using Kaplan-Meier analysis was IOP < 21 mmHg without medications (complete success) or fewer drugs than preoperatively (qualified success) at the last visit, without new surgery or unresolved hypotony. Results: No significant preoperative differences were found between the groups. The mean IOP was 15.6 ± 3.8 mmHg in MCE and 15.1 ± 4.1 mmHg in the MUE group (p > 0.05; Mann-Whitney test) at the end of the follow-up (mean of 26.1 ± 15.6 months and 28.3 ± 15.3 months, respectively) (p = 0.414, Mann-Whitney Test). The device caused a significant IOP reduction at 24 h in both groups. Thereafter, the MCE group significantly tended to increase IOP, recovering baseline values at 1 month and maintaining them until the end of the follow-up. In contrast, in the MUE group, the IOP values tended to be similar after the first reduction. No relevant complications and no significant differences between the groups in the survival analysis were found. Conclusions: XEN45 provided stable IOP control in both the MCE and MUE group without important complications in the medium term. The IOP increasing in the MCE group, after a prior decrease, led to restored baseline values 1 month after surgery. The homeostatic mechanism that causes the rise in the IOP to baseline values and its relationship with failure cases remains to be clarified.

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.

Complications of XEN gel stent implantation for the treatment of glaucoma: a systematic review.

Aim: This study was aimed to summarize the complications and their management associated with XEN gel stent implantation. Methods: A systematic review of literature was conducted using Medline (via PubMed), EMBASE, the Cochrane Library databases, and China National Knowledge Infrastructure, from their inception to February 1, 2024. Results: A total of 48 studies published between 2017 and 2024 were identified and included in the systematic review, including 16 original studies (retrospective or prospective clinical studies), 28 case reports, and 4 case series, which followed patients for up to 5 years. Early postoperative complications of XEN gel stent implantation include hypotony maculopathy (1.9-4.6%), occlusion (3.9-8.8%), suprachoroidal hemorrhage (SCH), choroidal detachment (0-15%), conjunctival erosion, and exposure of the XEN gel stent (1.1-2.3%), wound and bleb leaks (2.1%) and malignant glaucoma (MG) (2.2%). Mid-postoperative complications of XEN gel stent implantation included migration of XEN (1.5%), ptosis (1.2%), endophthalmitis (0.4-3%), macular edema (1.5-4.3%), hypertrophic bleb (8.8%) and subconjunctival XEN gel stent fragmentation (reported in 2 cases). Late postoperative complications reported in cases included spontaneous dislocation and intraocular degradation. Conclusion: XEN gel stent implantation is a minimally invasive glaucoma surgery (MIGS) procedure for glaucoma, known for its potential to minimize tissue damage and reduce surgical duration. However, it is crucial to note that despite these advantages, there remains a risk of severe complications, including endophthalmitis, SCH, and MG. Therefore, postoperative follow-up and early recognition of severe complications are essential for surgical management.

One year efficacy and safety of inferior implantation of Xen 45® Gel Stent in refractory glaucoma.

PURPOSE: The goal of this study was to assess the efficacy and safety of inferior implantation of the Xen Gel 45® Stent in a cohort of refractory glaucoma patients who had undergone multiple failed procedures and lacked healthy superior conjunctiva. PATIENTS AND METHODS: We retrospectively included individuals with refractory glaucoma who underwent implantation of a Xen 45® in the inferior quadrants of the conjunctiva. At the 12-month mark, two success criteria were assessed: "Complete" success, defined as an intraocular pressure (IOP)≤21mmHg with a≥20% reduction in IOP without additional IOP-lowering medications, the absence of a requirement for additional filtering surgery, and the absence of chronic hypotony; and "Qualified" success, which consisted of patients meeting the same criteria but requiring glaucoma medications postoperatively. Safety was also monitored throughout the 12-month follow-up. RESULTS: A total of 35 patients who underwent inferior Xen implantation were assessed. After 12months, 20 patients (57.1%) achieved qualified success, with twelve patients (34.3%) attaining complete success. Excluding five patients who underwent additional filtering surgery during follow-up, the mean IOP decreased significantly from 30.73±9.7mmHg to 16.49±7.9mmHg, representing a mean decrease of 14.24±12.13mmHg (46.5%; P<0.0001). The mean number of medications at 12months decreased from 3.43±1.6 to 1.53±1.52 (-55.4%; P<0.0001). The mean number of needlings was 1.29±1.2. Implant exposure was observed in two patients during the first postoperative month. CONCLUSIONS: Inferior placement of Xen appears to be a viable treatment option for patients with refractory glaucoma and a history of multiple failed glaucoma procedures. It demonstrates both significant efficacy and acceptable safety.

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 ±â€¯4.9 mmHg at the first visit to a mean of 17.1 ±â€¯5.3 (P = .001) at the sixth month. Drug use required between the first visit and Xen implantation was reduced from 2.1 ±â€¯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.

One-Year Outcomes of Ab Externo XEN45 Gel Stent Implantation with an Open Conjunctiva Approach in Patients with Open-Angle Glaucoma.

PURPOSE: This study aimed to evaluate the 1-year surgical outcomes of XEN45 gel stent implantation with an open conjunctiva approach in patients with open-angle glaucoma (OAG). METHODS: This retrospective cohort study included 19 eyes of 19 patients who underwent XEN45 gel stent implantation with an open conjunctival approach. Surgical success was defined by intraocular pressure (IOP) ≤18 mmHg and one of the following: IOP reduction ≥30% or reduction of two glaucoma medications with final IOP if baseline IOP ≤18 mmHg. The cumulative probability of success rate was analyzed using Kaplan-Meier survival analysis. Cox proportional hazard regression analysis was used to assess prognostic factors for surgical failure. RESULTS: IOP reduced from 32.37 ± 12.08 mmHg preoperatively to 15.14 ± 2.25 mmHg at 1 year (p = 0.001). The number of glaucoma medication reduced from 3.89 ± 0.32 preoperatively to 0.86 ± 1.35 at 1 year (p = 0.001). The success rates were 78.9% at 6 months and 73.7% at 1 year. Eyes with bleb horizontal extent ≥2 clock hours at 1 month postoperatively had a significantly higher success rate (log-rank test, p < 0.001). Greater bleb horizontal extent at 2 weeks and 1 month postoperatively was associated with a lower surgical failure rate (2 weeks: hazard ratio, 0.119; p = 0.024; 1 month: hazard ratio, 0.046; p = 0.007). Bleb needling and additional glaucoma surgeries were necessary in 10 (52.6%) and five eyes (26.3%), respectively. CONCLUSIONS: XEN45 gel stent implantation with the open conjunctiva approach is effective in reducing IOP and glaucoma medication for over 1 year in patients with OAG.

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.

A Case of Bilateral Choroidal Effusion after XEN Gel Stent Implantation.

PURPOSE: This study aimed to describe a rare case of bilateral choroidal effusion following a XEN45 implantation. CASE REPORT: An 84-year-old man with primary open-angle glaucoma underwent uneventful ab interno XEN45 device implantation in the right eye. The immediate postoperative period was complicated by hypotony and serous choroidal detachment, which were treated and resolved using steroids and cycloplegic drops. Eight months later, the fellow eye underwent the same surgery, which was followed by choroidal detachment that required transscleral surgical drainage. CONCLUSIONS: This case highlights the importance of a careful postoperative follow-up and a timely intervention in the context of XEN45 implantation, and suggests that choroidal effusion in one eye may be a risk factor for choroidal effusion in the other eye when undergoing the same type of surgery.

Transconjunctival XEN45 implantation for secondary open-angle glaucoma management in a pediatric patient with WAGR syndrome.

Purpose: To report a case of XEN45 gel stent implantation in a pediatric patient with WAGR syndrome as a successful surgical intervention in the management of multifactorial secondary open-angle glaucoma. Observations: A 6-year-old female with a history of WAGR syndrome, bilateral congenital aniridia, pseudophakia OD and glaucoma OD, was referred for a XEN45 gel stent OD. IOP was persistently elevated at 24 mm Hg despite two glaucoma medications. Implantation of the XEN45 gel stent was performed using a transconjunctival ab externo approach. There were no significant intra-or-postoperative adverse events associated with the stent. The patient achieved good IOP-lowering control without glaucoma medications across the 18-month follow-up period. Conclusions: A XEN45 stent through a transconjunctival ab externo approach may be an effective surgical intervention in pediatric patients with secondary open-angle glaucoma associated with aniridia and aphakia.

Four-Year Outcome of XEN 45 Gel Stent Implantation in a Swedish Population.

Purpose: To report the long-time success rate of XEN 45 gel stent implantation in a Scandinavian population. Patients and Methods: This was a retrospective single-center analysis of all patients undergoing XEN 45 stent surgery between December 2015 and May 2017. The main outcome was success rate according to several definitions of success. Subgroup analysis was performed. Secondary outcomes were change in intraocular pressure (IOP) and number of IOP-lowering agents. Need for secondary glaucoma surgery, needling rate and complications were recorded. Results: A total of 103 eyes could be evaluated after four years. Mean age was 70.6 years. Primary open-angle glaucoma (POAG) accounted for 46.6% and exfoliative glaucoma (PEXG) for 39.8%. Mean IOP dropped from 24.0 to 15.9 mmHg (p<0.001) and IOP-lowering agents from 3.5 to 1.5 (p<0.001). The success rate with individual target pressures after four years was 43.7%. Secondary glaucoma surgery was performed in 45 (43.7%) of cases. Combined cases (n=12) were not statistically different to stand-alone procedures (p=0.28). No difference between PEXG and POAG could be detected (p=0.44). During the learning curve, stent misplacement was common and resulted in worse outcome for less experienced surgeons. Conclusion: The overall success rate of XEN 45 gel stent surgery in the present cohort is relatively low in a long-time follow-up under the given circumstances if all initial patients are included to follow-up. The influence of the surgeon's learning curve is obvious, and improvement in success can be expected when used by experienced and high-volume surgeons. No significant differences were found in PEXG compared to POAG or in XEN surgery combined with cataract surgery compared to stand-alone.