3-year Outcomes of XEN Implant Compared to Trabeculectomy, With or Without Phacoemulsification for Open-angle Glaucoma

Real-world comparison of efficacy and safety of XEN45 implant with phacoemulsification versus iStent inject® W with phacoemulsification

PURPOSE

To compare iStent inject® W+phacoemulsification with XEN45 implant+phacoemulsification over 12 months in mild to moderate glaucoma patients needing cataract surgery at the Hospital General Universitario Dr. Balmis, Alicante, Spain.

METHODS

Retrospective clinical cohort study. Consecutive patients who underwent phacoemulsification either combined with XEN45 implantation or iStent inject® W from 2020 to 2022 were included. The main outcome measure was surgical success at 12 months postoperatively. Intraocular pressure (IOP), number of antiglaucoma medications, intraoperative and postoperative complications, number of revision surgeries, use of the operating room and required visits were also evaluated.

RESULTS

A total of 167 eyes were included in the study, with 101 eyes of 61 patients undergoing iStent+PHACO and 66 eyes of 46 patients undergoing XEN45+PHACO. The proportion of patients achieving a complete success (IOP≥5 and ≤ 18mmHg without medication) at the conclusion of the 12-month follow-up was 47.9% (35/73) in the iStent+PHACO and 48.2% (27/56) in the XEN45+PHACO surgery group, P=1.000. The mean (95% CI) IOP reduction at the conclusion of the study follow-up was -2.4 (-3.5 to -1.3mmHg, P<0.001, iStent+PHACO) and -3.10 (-4.8 to -1.4mmHg, P<0.001, XEN45+PHACO). The mean number of antiglaucoma medications was significantly reduced in both study groups. Rates of intraoperative complications (5 vs. 15.2%), postoperative complications (1 vs. 46.2%), reoperations (0 vs. 24.6%), mean number of operating room visits (1 vs. 1.41), and mean number of required postoperative visits (4.50 vs. 11.13) were all statistically significantly higher in the XEN45+PHACO group (< 0.001).

CONCLUSIONS

Both procedures achieved similar surgical success rates, with comparable reductions in IOP and the number of antiglaucoma medications. After one year, a modest IOP reduction of 10.83% was observed in the iStent group and 13.65% in the Xen group. However, the iStent inject® W demonstrated a better intraoperative and postoperative safety profile.

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.

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.

Long-term Outcomes of PreserFlo MicroShunt versus XEN45 Gel Stent in Open-Angle Glaucoma

PURPOSE

To compare two glaucoma drainage devices with subconjunctival filtration (MicroShunt and XEN) for open-angle glaucoma (OAG), with respect to effectiveness and safety.

PATIENTS AND METHODS

This is a single center, retrospective, interventional study. In total, 106 eyes of 95 patients with OAG underwent surgery. Of these patients, 51 eyes of 45 patients received a MicroShunt implantation and 55 eyes of 50 patients received an XEN implantation. Failure was defined as an intraocular pressure (IOP) lower than 5 or higher than 17 mmHg at the end of follow-up after 2 years, the need for surgical revision, secondary glaucoma surgery, or loss of light perception. Outcome was rated as complete success or qualified success, depending on whether it was achieved with or without anti-glaucomatous medications. Postoperative complications and interventions were also documented for both groups.

RESULTS

In the MicroShunt group, mean IOP decreased from 20.6 ± 7.5 mmHg at baseline to 13.0 ± 3.9 mmHg (p < 0.0001) after 2 years. In the XEN group, mean IOP was lowered from 22.5 ± 7.9 mmHg to 13.5 ± 4.2 mmHg (p < 0.0001). In both groups, the mean number of medications was significantly reduced (MicroShunt 2.7 ± 1.2 to 0.9 ± 2.5; p < 0.0001 vs. XEN 3.2 ± 0.9 to 1.1 ± 1.5; p < 0.0001). In regard to success rates, 37% of MicroShunt patients achieved complete success and 57% qualified success at the end of follow-up. In the XEN group, rates were 25 and 45%, respectively. Patient demographics differed between the two groups with respect to age (MicroShunt 72.8 ± 8.7 vs. XEN 67.7 ± 9.0 years; p = 0.002). Postoperative complications were comparable between the two groups.

CONCLUSION

Both MicroShunt and XEN are effective in significantly reducing IOP and glaucoma medications in OAG, and with 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.

Long-term efficacy and safety of XEN-45 gel stent implantation in patients with normal-tension glaucoma

BACKGROUND

Minimally invasive bleb surgery using the XEN-45 gel stent has not been established for the treatment of normal-tension glaucoma (NTG). The main objective of this study was to evaluate the long-term treatment efficacy and safety of XEN-45 in eyes with uncontrolled NTG.

METHODS

A retrospective analysis of patients with NTG who underwent XEN-45 gel stent implantation at university hospital Tuebingen between 2016 and 2021. The primary outcome measure was surgical success after three years defined as lowering of intraocular pressure (IOP) of ≥ 20%, with target IOP between 6 and 15 mmHg. Success was complete without and qualified irrespective of topical antiglaucoma medication use. The need for further glaucoma surgery, except for needling, was regarded as a failure. The secondary outcome measures included changes in mean IOP, number of antiglaucoma medications, and needling and complication rates.

RESULTS

Twenty-eight eyes from 23 patients were included in the final analysis. Complete and qualified success rates were 56.5% and 75% after three years, respectively. Mean postoperative IOP ± standard deviation decreased significantly after three years from 19.3 ± 2.0 mmHg at baseline to 13.7 ± 4.2 mmHg (n = 22; p < 0.0001). The median number of antiglaucoma medications decreased from 2 (range 0-4) to 0 after three years (range 0-3; p < 0.0001). Sixteen eyes (57%) required a median of 1 (range 1-3) needling procedures. One eye required further glaucoma surgery. No sight-threatening complications were observed.

CONCLUSION

The XEN-45 stent is effective and safe for the long-term treatment of NTG. However, needling was frequently required to improve outcomes.

Comparing Outcomes of Trabeculectomy with Mitomycin C to 45 μm Gelatin Stent Placed Ab Externo with Open Conjunctiva

PURPOSE

To compare trabeculectomy with mitomycin C (trab-MMC) and XEN45 Gel Stent placed ab externo with open conjunctiva (XGS AEO) with or without cataract surgery in patients with glaucoma.

DESIGN

Nonrandomized, retrospective, comparative study.

SUBJECTS

A total of 204 eyes from 204 glaucoma patients who received XGS AEO or underwent trab-MMC with or without cataract surgery between July 2018 and August 2021 at Massachusetts Eye and Ear.

METHODS

Visits from 204 patient charts were reviewed after either trab-MMC or XGS AEO from 2018 to 2021 from a level 3 triage center.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP), medication burden, Kaplan-Meier success rates, 5-fluorouracil impact, and complications.

RESULTS

One hundred fifty-seven patients underwent trab-MMC and 47 underwent XGS AEO. Groups had similar baseline intraocular pressure (IOP) and medications (meds). Intraocular pressure and meds decreased similarly at 1.5 years (11.2 mmHg vs. 7.4 mmHg, P = 0.62; 2.9 vs. 2.8 meds, P = 0.92, respectively for trab-MMC and XGS AEO). Success was defined as IOP reduction ≥ 20% with 5 mmHg ≤ IOP ≤ 18 mmHg for 2 consecutive visits. Complete success (CS) did not allow meds; qualified success (QS) allowed for ≤ baseline meds. When IOP fluctuations in the first 60 days were not counted as failures, CS was 43% for trab-MMC, about 8.5% higher than for XGS AEO (P < 0.01). Qualified success was similar between the groups (65%-67%). Procedure time was shorter for XGS AEO than trab-MMC (44 vs. 63 minutes, P < 0.01).

CONCLUSIONS

XEN45 Gel Stent AEO may provide similar benefits to trab-MMC, especially for patients who tolerate some meds, with shorter procedure times.

FINANCIAL DISCLOSURE(S)

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

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.

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.

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.