Effective treatment of a normal-tension glaucoma patient with bilateral ab externo XEN Gel Stent implantation

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.

Comparing Outcomes of 45 Xen Implantation Ab Interno With Closed Conjunctiva to Ab Externo With Open Conjunctiva Approaches

PRCIS

Ab externo with open conjunctiva placement may lead to improved gelatin stent (XEN Gel Stent; Allergan) success rate compared with ab interno with closed conjunctiva because it conferred more favorable intraocular pressure (IOP) and medication burden reduction based on our complete and qualified success criteria.

PURPOSE

To compare outcomes of a gelatin stent (XEN 45 Gel Stent; Allergan) placed either ab interno with closed conjunctiva (AIC) or ab externo with open conjunctiva (AEO) with or without cataract surgery in patients with glaucoma.

DESIGN

Retrospective, nonrandomized comparative study of 85 eyes from 85 glaucoma patients who received XEN 45 Gel Stent placed either AIC (N=32) or AEO (N=53) with or without cataract surgery between July 2018 and January 2022 at Massachusetts Eye and Ear. Patients were included if they were 18 years of age or above and had at least 30 days of follow-up without any disqualifying event.

RESULTS

Baseline demographics were similar between both groups, except for the glaucoma type. Both AIC and AEO procedures resulted in significant patterns of IOP and medication reduction from baseline up to 1 year. At postoperative year (POY)1, mean IOP was reduced to 11.34±4 mmHg on 1.29±1.34 medications after AEO and 13.70±3.32 mmHg on 2±1.81 medications after AIC. The average IOP reduction was significantly greater in the AEO group at all postoperative time points beyond postoperative week 2. There were significant differences in the survival curves of AEO and AIC groups under both the complete success criteria and the qualified success criteria. Under the complete success criteria, the cumulative probability of survival at POY1 was 28.5% in the AEO group and 3.8% in the AIC group. Under the qualified success criteria, the cumulative probability of survival at POY1 was 60.3% in the AEO group and 21.9% in the AIC group.

CONCLUSIONS

In our study, we demonstrate that both placements reduce IOP and medication from baseline, with AEO placement having more favorable success rates compared with AIC placement.

A Case of Refractory Open-angle Glaucoma with Failed Baerveldt Glaucoma Implant and Trabeculectomy Treated with Ab Externo XEN Gel Stent Placement

Aim

We report a case of successful intraocular pressure (IOP) management in a patient with refractory primary open-angle glaucoma (POAG) following implantation of XEN gel implant in the same hemisphere as prior failed filtering surgeries [i.e., Baerveldt glaucoma implant (BGI) and trabeculectomy bleb)].

Background

Glaucoma is a major cause of blindness worldwide and is typically associated with elevated IOP and retinal ganglion cell loss. Treatment centers around decreasing IOP with eye drops and surgical interventions. The advent of minimally invasive glaucoma surgeries (MIGS) has expanded therapeutic options for patients who have failed traditional treatments. The XEN gel implant creates a shunt between the anterior chamber and the subconjunctival or sub-tenon's space, allowing for drainage of aqueous humor without significant tissue disruption. Given that the XEN gel implant also results in bleb formation, it is generally recommended to avoid placement in the same quadrant of prior filtering surgeries.

Case description

A 77-year-old man with a 15-year history of severe POAG of OU presents with persistently elevated IOP despite multiple filtering surgeries and maximal eye drop regimen. The patient had a superotemporal BGI in OU and a scarred trabeculectomy bleb superiorly in the right eye (OD). He underwent an open conjunctiva ab externo XEN gel implant placement in the OD in the same hemisphere as previous filtering surgeries. At 12 months postoperatively, the IOP range continues to be maintained within goal without complications.

Conclusion

The XEN gel implant can be successfully placed in the same hemisphere as prior filtering surgeries and can achieve goal IOP without any surgical complications at 12 months postoperatively.

Clinical significance

A XEN gel implant can effectively lower patients' IOP and can be a unique surgical option in refractory cases of POAG with multiple failed filtering surgeries, even when inserted in close proximity to prior filtering surgeries.

How to cite this article

Amoozadeh SA, Yang MC, Lin KY. A Case of Refractory Open-angle Glaucoma with Failed Baerveldt Glaucoma Implant and Trabeculectomy Treated with Ab Externo XEN Gel Stent Placement. J Curr Glaucoma Pract 2022;16(3):192-194.

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.

Retrospective Analysis of 12 Months Glaucoma Implant Efficacy: XEN45 and PreserFlo Microshunt

PURPOSE

Several new implant devices have recently been introduced to glaucoma surgery using various techniques for reducing intraocular pressure (IOP). Two implants introduced during the past couple of years, XEN45 and PreserFlo Microshunt, are both designed to control subconjunctival filtration. There are two Swiss multicenter studies that collected the data retrospectively to analyze the efficacy and safety of these two devices separately. In this study, we report the analysis of the combined data subset from the University Hospital of Basel.

SUBJECTS AND METHODS

The XEN45 implantation technique was introduced to Basel University Hospital in 2016 and PreserFlo Microshunt in 2018. Sixty operated patients, thirty in each group, were operated on by one surgeon, clinically followed up, and their data retrospectively analyzed from medical records. Only standalone procedures, without combined phacoemulsification, were considered in this analysis; the lens status, however, was neither an inclusion nor an exclusion criterion. Further inclusion criteria were the diagnosis of open-angle glaucoma, no previous glaucoma surgery, other than laser trabeculoplasty, and complete medical records during the 12 months of follow-up. IOP reduction during a 12-month postoperative period was the primary outcome measure as well as the number of IOP reducing drugs. The number of subsequent surgical interventions and complications/adverse events are descriptively reported.

RESULTS

Patient age, gender, ophthalmological diagnosis, and initial preoperative IOP were well balanced between the two groups. Postoperative IOP course was comparable between the two methods for the first 12 months. IOP measurements were taken preoperatively and then on the first postop day, week 1, month 1, and months 3, 6, and 12 for the PreserFlo Microshunt vs. XEN45 (mmHg): 23.6 vs. 24.9, 9.0 vs. 8.9, 11.4 vs. 10.6, 13.0 vs.18.3, 16.8 vs.15.1, 15.9 vs.15.0, and 15.4 vs.14.5, respectively. IOP reducing medications were also comparable between the two groups. The study showed that subsequent interventions were more frequent in the XEN45 (13) than in the PreserFlo Microshunt group (7).

CONCLUSION

Both methods demonstrate satisfactory IOP control within a 12-month postoperative period with practically no serious adverse events/complications, but with relatively high numbers of subsequent interventions (needlings), particularly in the XEN45 group.