Efficacy and safety of XEN®-Implantation vs. trabeculectomy: Data of a "real-world" setting

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.

Two-Year Results of XEN Gel Stent Implantation for Pseudoexfoliative Glaucoma in Phakic versus Pseudophakic Eyes

Objectives: To investigate whether phakia affects the outcome of XEN-45 gel stent implantation in the treatment of pseudoexfoliative glaucoma (PXG). Methods: A retrospective, comparative cohort study of 30 phakic and 55 pseudophakic PXG patients who received the XEN-45 gel stent at a tertiary centre. The primary outcome measure was two-year success defined as a ≥20% lowering of intraocular pressure (IOP) and a target IOP of 6-21 mmHg. Success was complete without and qualified irrespective of antiglaucoma medication use. Further glaucoma surgery other than needling was regarded as a failure. The secondary outcome measures included changes in IOP, revision and complication rates. Results: The complete two-year success rates were 70% and 59% in the phakic and pseudophakic groups, respectively (p = 0.75, log-rank test), and the qualified rates were 80% and 72%, respectively (p = 0.89). The median IOP reduction from baseline was 54% in phakic, and 46% in pseudophakic eyes. While needling rates were similar, the incidence of early incisional bleb revisions was significantly higher in the phakic eyes (13% vs. 0% within 3 months; p = 0.0098, chi-square). Increasing after a year, significantly more pseudophakic eyes failed due to secondary glaucoma surgery (16% vs. 0%; p = 0.0191). Conclusions: The XEN-45 gel stent offers equally effective IOP control for both phakic and pseudophakic patients. However, the onset of bleb revisions and the necessity for secondary glaucoma surgery differed significantly between the groups.

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.

[Glaucoma Filtration Surgery - Bleb-forming Procedures]

Glaucoma filtration surgery has been a standard surgical therapy for decades. An increasing knowledge about wound healing processes in the eye, the introduction of antimetabolite treatment and continuous improvements of the surgical technique helped making trabeculectomy - the prototype filtration surgery - a very effective therapeutic tool. However, best results will only be regularly achieved with a high level of experience and time dedicated to postoperative follow-up. Furthermore, the potential for severe early and late complications still remains high. Thus, novel stent-based filtration surgery approaches, such as the Preserflo and the XEN shunt have been introduced. This review presents these three bleb-forming filtration procedures, covering the basic principles of surgical technique, data on effectivity as well as complications.

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.

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.

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.

Factors Associated with the Efficacy of XEN Gel Implant

INTRODUCTION

Microinvasive glaucoma surgery (MIGS) is a growing trend, and XEN gel implant is one of the most effective types of MIGS. This study aimed to examine factors associated with the surgical success of XEN gel implants.

METHODS

This retrospective cohort study enrolled patients with glaucoma receiving XEN implantation alone or combined with phacoemulsification (PHACOXEN) with a follow-up period of more than 6 months at Hualien Tzu Chi Hospital, Taiwan. If intraocular pressure (IOP) elevated above 20 mmHg during the follow-up, needling or open revision was performed. The primary outcome measures included IOP and the number of glaucoma medications.

RESULTS

Male patients had lower postoperative IOP; male patients and higher preoperative IOP were associated with higher IOP change rates, and older patients had a higher chance of achieving IOP < 18 mmHg and being medication-free at months 12, 24, and 36. The Kaplan-Meier curve showed that the probability of free-of-rescue intervention over the follow-up period was not different between the XEN alone and the PHACOXEN group (P = 0.859). Both needling and open revision were effective rescue interventions, but open revision had a higher chance of achieving IOP ≤ 18 mmHg and being medication-free (P = 0.031) and required less medication afterward (P = 0.044). Older age (P = 0.013) and male patients (P = 0.022) had a lower IOP after rescue interventions. Compared with open revision, needling was associated with higher IOP (P = 0.048) and more required medications (P = 0.048).

CONCLUSIONS

XEN alone and PHACOXEN had comparable surgical outcomes, whereas open revision had a better IOP lowering effect than needling as a rescue intervention. Male and older patients had better surgical results in primary XEN implantations and rescue interventions.

Inferior implant of XEN63 Gel stent in a refractory open-angle glaucoma due to silicone oil tamponade: A case report

BACKGROUND

To discuss the efficacy of an inferior implant of XEN 63 gel stent in a patient with refractory glaucoma after trabeculectomy failure and vitreoretinal surgery with silicone oil tamponade.

CASE DESCRIPTION

We report the case of a 73-year-old man with a history of refractory open glaucoma with trabeculectomy failure. He experienced recurrent retinal detachments with silicone oil tamponade, with uncontrolled intra-ocular pressure (IOP) after silicone oil removal. Due to the presence of oil emulsion in the anterior chamber, the chosen location for XEN 63 implantation was the infero-temporal quadrant. Mild hyphema and vitreous hemorrhage were seen post-operatively, but were self-limiting. At week 1, the intraocular pressure was 8 mmHg with a well-formed bleb seen in anterior segment optical coherence tomography (AS-OCT). At 6 month follow up, the patient maintained a IOP of 12 mmHg without topical hypotensive drugs. Slit lamp examination revealed a widespread, developed bleb with no signs of inflammation.

CONCLUSION

In this case of refractory glaucoma in a vitrectomized eye with previous oil tamponade, the inferior placement of the XEN 63 gel stent delivered an adequate intraocular pressure even at 6-months follow up, with a diffuse functional infero-nasal bleb seen with AS-OCT.

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.

XEN 45 Gel Stent Implantation in Open Angle Glaucoma: 5-Year Results of a Prospective Study

PRCIS

XEN 45 Gel Stent is safe and effective for 3 years. The study results provide useful insight into the outcome of XEN 45 Gel Stent surgery over 5 years in daily clinical practice.

PURPOSE

To evaluate 5-year outcomes of XEN 45 gel stent implantation (XEN) in patients with open angle glaucoma.

METHODS

This is a prospective, single-center, interventional study. XEN implantation either alone (XEN) or combined with phacoemulsification (Phaco + XEN) was performed on 170 consecutive eyes (126 patients) with uncontrolled intraocular pressure (IOP) or disease progression despite medical treatment. "Complete" surgical success at 60 months was defined as unmedicated IOP ≤15 mm Hg and a relative IOP reduction ≥20% from medicated baseline, while "qualified" success allowed fewer ocular hypotensive medications than at baseline. Other definitions of success with various IOP targets were also analyzed. Secondary outcomes included mean IOP and IOP-lowering medication changes and rates of reoperations.

RESULTS

Mean age was 78.1±9.2 years, and 70.3% were female. Mean medicated IOP decreased from 19.8±7.7 mm Hg [19.6±7.1 (XEN) vs. 19.8±7.0 mm Hg (Phaco+XEN)] at baseline to 12.6±3.1 mm Hg [12.5± 3.1 (XEN) vs. 12.6±3.1 (Phaco+XEN)] at 5 years (-37.0%; P < 0.001). Medications decreased from 2.0±1.3 [2.0±1.3 (XEN) vs. 2.0±1.3 (Phaco+XEN)] to 0.8±1.1 [0.8±1.1 (XEN) vs. 0.8±1.1 (Phaco + XEN)] (-60%; P <0.001). Needling was performed in 84 eyes (49%), and 19.4% underwent a secondary surgical intervention. Complete success at 3 years was a strong predictor of success at 5 years (odds ratio: 3.06, P <0.01), while needling was associated with higher rates of failure (odds ratio: 3.6, P <0.01).

CONCLUSIONS

At 5 years, XEN gel stent implantation was a safe procedure and achieved clinically meaningful IOP and medication reduction. Success at 3 years is a predictor of success at 5 years. Needling correlates with higher failure rates.

Bleb Morphology on Anterior-Segment Optical Coherence Tomography after XEN Gel Stent Implantation

We investigated the internal morphology of filtration blebs after XEN gel stent implantation using anterior segment optical coherence tomography (AS-OCT) and identified factors related to intraocular pressure (IOP) postoperatively. Eighteen eyes of 18 patients who had undergone XEN gel stent implantation were analyzed. Blebs were imaged using Visante OCT (Carl Zeiss Meditec AG, Germany) at 6 months and 1 year after surgery and evaluated for quantitative parameters including bleb height, maximum height of internal cavity, maximum bleb wall thickness, and maximum bleb epithelial thickness. Subjects were classified into two groups according to the presence or absence of a definite internal cavity between the conjunctiva and sclera using AS-OCT imaging. Nine eyes (50%) were assigned to the internal cavity group and 9 (50%) to the uniform group. Postoperative IOP was significantly lower in the internal cavity group than in the uniform group both at 6 months and 1 year after surgery (p = 0.024 and p = 0.040). Postoperative IOP showed statistically significant negative correlations with bleb height and the height of the internal cavity (Spearman correlation coefficient r = -0.518, p = 0.028 and r = -0.453, p = 0.034, respectively). AS-OCT facilitates analysis of bleb morphology after XEN gel stent implantation. A larger height of the internal cavity of the bleb appeared to correlate with lower IOP after XEN implantation.

Endophthalmitis Associated With XEN Stent Implantation

PURPOSE

The aim of this study is to report the clinical characteristics, causative organisms, and treatment outcomes in patients presenting with endophthalmitis related to XEN stent implants.

DESIGN

Retrospective, noncomparative consecutive case series.

METHODS

Clinical and microbiologic review was performed for 8 patients presenting to the Bascom Palmer Eye Institute Emergency Room between 2021 and 2022 with XEN stent-related endophthalmitis. Data collected included clinical characteristics of patients at presentation, organisms identified in ocular cultures, treatments received, and visual acuity at last follow-up.

RESULTS

The current study included 8 eyes from 8 patients. All cases of endophthalmitis occurred >30 days after implantation of the XEN stent. At the time of presentation, there were external exposures of the XEN stent in 4 of 8 patients. Five of the 8 patients had positive intraocular cultures, all of which were variants of staphylococcus and streptococcus species. Management included intravitreal antibiotics in all patients, explantation of the XEN stent in 5 patients (62.5%), and pars plana vitrectomy in 6 patients (75%). At last follow-up, 6 of the 8 patients (75%) had a visual acuity of hand motion or worse.

CONCLUSIONS

Endophthalmitis in the setting of XEN stents results in poor visual outcomes. The most common causative organisms are staphylococcus or streptococcus species. At time of diagnosis, prompt treatment with broad-spectrum intravitreal antibiotics is recommended. Consideration can be made to explant the XEN stent and perform early pars plana vitrectomy.

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.

Gel Stent Versus Trabeculectomy: The Randomized, Multicenter, Gold-Standard Pathway Study (GPS) of Effectiveness and Safety at 12 Months

PURPOSE

To compare effectiveness and safety of the gel stent to trabeculectomy in open-angle glaucoma (OAG).

DESIGN

Prospective, randomized, multicenter, noninferiority study.

METHODS

Patients with OAG and intraocular pressure (IOP) 15 to 44 mm Hg on topical IOP-lowering medication were randomized 2:1 to gel stent implantation or trabeculectomy. Primary end point (surgical success): percentage of patients at month 12 achieving ≥20% IOP reduction from baseline without medication increase, clinical hypotony, vision loss to counting fingers, or secondary surgical intervention (SSI) in a noninferiority test with 24% margins. Secondary end points (month 12) included mean IOP and medication count, postoperative intervention rate, visual recovery, and patient-reported outcomes (PROs). Safety end points included adverse events (AEs).

RESULTS

At month 12, the gel stent was statistically noninferior to trabeculectomy (between-treatment difference [Δ], -6.1%; 95% CI, -22.9%, 10.8%); 62.1% and 68.2% achieved the primary end point, respectively (P=.487); mean IOP and medication count reductions from baseline were significant (P<.001); and the IOP change-related Δ (2.8 mm Hg) favored trabeculectomy (P=.024). The gel stent resulted in fewer eyes requiring in-office postoperative interventions (P=.024 after excluding laser suture lysis), faster visual recovery (P≤.048), and greater 6-month improvements in visual function problems (ie, PROs; P≤.022). The most common AEs were reduced visual acuity at any time (gel stent, 38.9%; trabeculectomy, 54.5%) and hypotony (IOP <6 mm Hg at any time) (gel stent, 23.2%; trabeculectomy, 50.0%).

CONCLUSIONS

At month 12, the gel stent was statistically noninferior to trabeculectomy, per the percentage of patients achieving ≥20% IOP reduction from baseline without medication increase, clinical hypotony, vision loss to counting fingers, or SSI. Trabeculectomy achieved a statistically lower mean IOP, numerically lower failure rate, and numerically lower need for supplemental medications. The gel stent resulted in fewer postoperative interventions, better visual recovery, and fewer AEs.

Nanofiber-based glaucoma drainage implant improves surgical outcomes by modulating fibroblast behavior

Biomaterials are implanted in millions of individuals worldwide each year. Both naturally derived and synthetic biomaterials induce a foreign body reaction that often culminates in fibrotic encapsulation and reduced functional lifespan. In ophthalmology, glaucoma drainage implants (GDIs) are implanted in the eye to reduce intraocular pressure (IOP) in order to prevent glaucoma progression and vision loss. Despite recent efforts towards miniaturization and surface chemistry modification, clinically available GDIs are susceptible to high rates of fibrosis and surgical failure. Here, we describe the development of synthetic, nanofiber-based GDIs with partially degradable inner cores. We evaluated GDIs with nanofiber or smooth surfaces to investigate the effect of surface topography on implant performance. We observed in vitro that nanofiber surfaces supported fibroblast integration and quiescence, even in the presence of pro-fibrotic signals, compared to smooth surfaces. In rabbit eyes, GDIs with a nanofiber architecture were biocompatible, prevented hypotony, and provided a volumetric aqueous outflow comparable to commercially available GDIs, though with significantly reduced fibrotic encapsulation and expression of key fibrotic markers in the surrounding tissue. We propose that the physical cues provided by the surface of the nanofiber-based GDIs mimic healthy extracellular matrix structure, mitigating fibroblast activation and potentially extending functional GDI lifespan.

Comparison of tube shunt implantation and trabeculectomy for glaucoma: a systematic review and meta-analysis

OBJECTIVE

To compare the efficacy and safety of tube shunt implantation with trabeculectomy in the treatment of patients with glaucoma.

METHODS

A systematic literature search was performed for studies comparing tube with trabeculectomy in patients with glaucoma (final search date: 27 February 2022). Comparisons between tube and trabeculectomy were grouped by the type of tube (Ahmed, Baerveldt, Ex-PRESS and XEN). The primary endpoints included intraocular pressure (IOP), IOP reduction (IOPR), IOPR percentage (IOPR%), complete success rate (CSR), qualified success rate (QSR) and adverse events (AEs).

RESULTS

Forty-nine studies were included in this meta-analysis and presented data for 3795 eyes (Ahmed: 670, Baerveldt: 561, Ex-PRESS: 473, XEN: 199, trabeculectomy: 1892). Ahmed and Ex-PRESS were similar to trabeculectomy in terms of IOP outcomes and success rate (Ahmed vs trabeculectomy: IOPR%: mean difference (MD)=1.34 (-5.35, 8.02), p=0.69; Ex-PRESS vs trabeculectomy: IOPR%: MD=0.12 (-3.07, 3.31), p=0.94). The IOP outcomes for Baerveldt were worse than those for trabeculectomy (IOPR%: MD=-7.51 (-10.68, -4.35), p<0.00001), but the QSR was higher. No significant difference was shown for the CSR. XEN was worse than trabeculectomy in terms of IOP outcomes (IOPR%: MD=-7.87 (-13.55, -2.18), p=0.007), while the success rate was similar. Ahmed and Ex-PRESS had a lower incidence of AEs than trabeculectomy. Baerveldt had a lower incidence of bleb leakage/wound leakage, hyphaema and hypotonic maculopathy than trabeculectomy but a higher incidence of concurrent cataracts, diplopia/strabismus and tube erosion. The incidence of AEs was similar for the XEN and trabeculectomy procedures.

CONCLUSION

Compared with trabeculectomy, both Ahmed and Ex-PRESS appear to be associated with similar ocular hypotensive effects and lower incidences of AEs. However, Baerveldt and XEN cannot achieve sufficient reductions in IOP outcomes similar to those of trabeculectomy.

PROSPERO REGISTRATION NUMBER

CRD42021257852.

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.

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.

Safety and Efficacy of Ab Interno XEN 45 Gel Stent in Patients with Glaucoma and High Myopia

This study reports on the safety and efficacy of Xen 45 in patients with glaucoma and high myopia. It was a retrospective study including patients with high myopia (>6D) who underwent Xen implant with 2 years of follow-up. The primary outcome was to report the incidence of hypotony (IOP ≤ 5 mmHg) and hypotony-related complications. Patients with high myopia treated with mitomycin-C-augmented trabeculectomy were included as a control group. We included 14 consecutive patients who underwent Xen implant (seven eyes) and trabeculectomy (seven eyes). The mean myopia was −14.71 ± 5.36 and −15.07 ± 6.11 in the trabeculectomy and Xen groups, respectively (p > 0.05). The success rate and the mean IOP at 1 and 2 years from the intervention were statistically comparable between the two groups. The group undergoing trabeculectomy showed a higher incidence of hypotony (six eyes (85.71%) vs. two eyes (28.57%)) and hypotony maculopathy (three eyes (42.86%) vs. zero eyes (0%)) and required more postoperative procedures. Patients with high myopia were at higher risk of hypotony-related complications after trabeculectomy. The Xen implant can achieve an IOP control comparable to trabeculectomy with a significantly better safety profile and can be considered as an option for the management of patients with high myopia and glaucoma.

The PreserFlo MicroShunt in the Context of Minimally Invasive Glaucoma Surgery: A Narrative Review

Recently, the quest for novel glaucoma surgical techniques and devices has been underway. Trabeculectomy remains the gold standard, but it requires the implantation of glaucoma drainage devices and frequent follow-ups, and it also carries a high risk of serious complications. The need for less invasive and safer procedures has led to the development of minimally invasive glaucoma surgery (MIGS), particularly for patients with mild-to-moderate disease. Among them, minimally invasive bleb surgery seems to be effective in classical glaucoma surgery, while maintaining MIGS benefits. The relatively new PreserFlo® MicroShunt (Santen, Osaka, Japan) is registered in Europe. It was released in 2019 for the treatment of patients with early-to-advanced open-angle glaucoma, where intraocular pressure (IOP) remains uncontrolled while on maximum tolerated medication and/or where glaucoma progression warrants surgery. This review focuses on the place of the PreserFlo MicroShunt, characterized by ab externo implantation, among MIGS procedures, discussing its advantages and disadvantages. The mechanisms of action, technical aspects, efficacy, and safety issues are summarized. The surgical technique, its efficacy, and safety profile are described, and directions for future studies are indicated. The PreserFlo MicroShunt ensures a high safety profile, minimal anatomical disruption, meaningful IOP-lowering effect, and ease of use for patients and physicians.

Intraocular Pressure and Medication Changes Associated with Xen Gel Stent: A Systematic Review of the Literature

The Xen gel stent (Allergan Inc, an AbbVie company; Dublin, Ireland) was conceived as an option for patients requiring modest IOP reduction but for whom trabeculectomy was not yet indicated. As with any glaucoma surgery, establishing criteria for patient selection and identifying factors that contribute to a high likelihood of success are important. To help guide clinical decision-making, a systematic review of published studies on the gel stent was performed, with the goal of understanding postoperative outcomes based on clinical and patient factors. Results were organized around a series of pertinent clinical questions based on scenarios encountered in clinical practice. Criteria for including studies were intentionally broad, with the objective of simulating the diverse population of glaucoma patients encountered in real-world practice. Outcomes for IOP and medication reduction postoperatively were assessed in various analyses, including in eyes with various glaucoma types and severity; in eyes naïve to surgery as well as those with a history of prior incisional glaucoma surgery; and when surgery was performed as a standalone procedure or at the time of cataract surgery. The results of each of the various analyses were consistent in demonstrating that successful gel stent surgery achieved a postoperative IOP of approximately 14.0 mm Hg and reduction to fewer than 1 glaucoma medication. Additional data are shown on outcomes by method of implant (ab interno vs ab externo); intraoperative use of antifibrotics; and rates of needling in published studies.

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.

Comparison of surgical outcomes between initial trabeculectomy and Ex-PRESS in terms of achieving an intraocular pressure below 15 and 18 mmHg: a retrospective comparative study

Background

To evaluate the postoperative outcomes of initial trabeculectomy (Trab) and Ex-PRESS (EX) in terms of achieving an intraocular pressure (IOP) below 15 and 18 mmHg.

Methods

This study retrospectively analyzed 64 and 54 cases of Trab and EX, respectively, performed by the same surgeon with uniform management from April 2018 to March 2019. Surgical success was defined as 5 < IOP < 15 mmHg (criterion 1) and 5 < IOP < 18 mmHg (criterion 2) without additional glaucoma medication, needling, and bleb reconstruction 2 months after surgery. Survival analysis with Cox regression was performed to identify factors associated with postoperative outcomes.

Results

The Trab and EX groups had an IOP of 22.6 ± 6.2 vs. 21.8 ± 6.0 mmHg before surgery (P = 0.507), 12.6 ± 2.6 vs. 14.0 ± 4.4 mmHg (P = 0.06) at 6 months, 12.7 ± 2.3 vs. 12.9 ± 2.8 mmHg (P = 0.678) at 12 months, 13.3 ± 2.6 vs. 12.6 ± 2.8 mmHg (P = 0.260) at 18 months, and 13.2 ± 2.3 vs. 13.6 ± 2.8 mmHg (P = 0.444) at 24 months, respectively. The proportion of those with an IOP < 15 mmHg in the Trab and EX groups was 82% vs. 81% at 6 months, 68% vs. 62% at 12 months, 63% vs. 61% at 18 months, and 57% vs. 53% at 24 months, respectively. The log-rank test showed no significant difference between the groups for Criteria 1 (P = 0.755) and 2 (P = 0.138). The results of the multivariate logistic analysis identified only a high preoperative IOP as a risk factor for surgical failure (odds ratio for Criteria 1: 1.076, P = 0.009 and Criteria 2: 1.068, P = 0.048).

Conclusion

Postoperative outcomes of Trab and EX suggested similar ability for achieving an IOP below 15 and 18 mmHg without medications and interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-022-00279-1.

High-Frequency Deep Sclerotomy as Adjunctive Therapy in Open-Angle Glaucoma Patients

INTRODUCTION

Glaucoma is a chronic, progressive disease of the optic nerve that can cause vision loss and blindness. High-frequency deep sclerotomy (HFDS) is a novel ab interno procedure used to lower intraocular pressure (IOP). This study aims at examining hypotensive effects of HFDS in patients with medically uncontrolled primary open-angle glaucoma (POAG).

METHODS

23 patients (23 eyes) participated in this study. They were all affected by POAG and used maximum prescribed medical therapy. It is important to note that the target IOP was not detected in any study participant. The target IOP is the highest IOP value at which no new damages of the optic nerve occur. The procedure was performed with a custom-made, high-frequency dissection probe by applying bipolar current of 500 kHz. Six pockets (1 mm deep, 0.3 mm high, and 6 mm wide) were made ab interno in nasal sclera (through trabecular meshwork and Schlemm's canal). Tobramycin/dexamethasone and pilocarpine eye drops were administered postoperatively for a month.

RESULTS

The mean value of the base IOP had been 25.6 mm Hg before the procedure. Significant complications were not recorded either during the surgery or in a postoperative follow-up period. The average IOP for our patients reduced by 8.6 mm Hg (33.6%) after a year. The mean value of the instilled anti-glaucoma eye drops had been 2.78 (SD = 0.45) before the HFDS and 0.61 (SD = 1.04) at the end of the research. The target IOP was not achieved in five cases (21.7% of our sample).

DISCUSSION/CONCLUSION

This study presents the data on our first surgical experience with HFDS that was conducted on 23 patients who had medically uncontrolled POAG. The results indicate that HFDS is safe and efficient in reducing IOP.

Comparison of surgical outcomes with and without Ologen collagen matrix augmentation during XEN gel stent implantation

Background

To compare the surgical outcomes and postoperative complications with and without Ologen collagen matrix augmentation during XEN gel stent implantation.

Methods

We retrospectively analyzed patients who underwent XEN gel stent implantation with an ab externo technique. The amount of intraocular pressure (IOP) reduction, percentage of postoperative complications and additional management, and surgical success defined as IOP reduction greater than 20% compared with the preoperative IOP measurement were compared between Ologen-augmented and non-augmented groups. Groups of patients who underwent XEN gel stent implantation alone and combined with phacoemulsification were analyzed separately.

Results

A total 103 eyes of 103 participants were included. Of those, 72 eyes underwent standalone XEN gel stent implantation: 42 eyes with Ologen augmentation (Oloxen group) and 30 eyes without Ologen augmentation (Xen group). Thirty-one eyes underwent XEN gel stent implantation with phacoemulsification: 19 eyes with Ologen augmentation (Phaco-Oloxen group) and 12 eyes without Ologen augmentation (PhacoXen group). The surgical success rate at six months postoperatively was not different between the Oloxen and Xen groups (56.4% vs 43.3%, P > 0.05) or between the Phaco-Oloxen group and PhacoXen group (57.9% vs 41.7%, P > 0.05). The prevalence of postoperative hypotony, 5-fluorouracil injections, use of anti-glaucoma medications, bleb needling, and additional glaucoma surgeries was not different between the Oloxen and Xen groups or between the Phaco-Oloxen and PhacoXen groups when assessed six months postoperatively.

Conclusions

All groups showed significant IOP reduction after XEN gel stent implantation, but there was no significant difference between the Ologen collagen matrix augmented and non-augmented groups in surgical outcomes.

Two Year Functional and Structural Changes-A Comparison between Trabeculectomy and XEN Microstent Implantation Using Spectral Domain Optical Coherence Tomography

The aim of this study was to analyze retinal nerve fiber layer (RNFL) thickness after trabeculectomy (TE) versus XEN microstent implantation (XEN) in primary open-angle glaucoma (POAG) cases naïve to prior incisional glaucoma surgery. We examined 119 consecutive glaucoma patients retrospectively, who received a TE or XEN for medically uncontrolled POAG. Intraocular pressure (IOP), amount of IOP-lowering medication, mean deviation of standard automated perimetry and peripapillary RNFL thickness were evaluated during the first 24 months after surgery. Fifty eyes were treated with TE and 69 eyes with XEN. Mean IOP decreased from 25.1 ± 0.8 to 13.3 ± 0.6 mm Hg (p < 0.01) and mean number of IOP-lowering eye drops from 3.2 ± 0.2 to 0.4 ± 0.1 (p < 0.01) 24 months after TE. In 69 eyes undergoing XEN, mean IOP dropped from 24.8 ± 0.6 to 15.0 ± 0.4 mm Hg (p < 0.01) and medication from 3.0 ± 0.1 to 0.6 ± 0.1 (p < 0.01) during the 24 months follow-up. Mean deviation of standard automated perimetry remained stable in TE (8.5 ± 0.7 to 8.1 ± 0.8 dB; p = 0.54) and XEN group (11,0 ± 0.5 to 11.5 ± 0.5 dB; p = 0.12) after 24 months, while mean RNFL thickness further deteriorated in the TE (−2.28 ± 0.65 µm/year) and XEN (−0.68 ± 0.34 µm/year) group. Postoperative RNFL loss develops after TE and XEN despite effective and significant lowering of IOP and amount of IOP-lowering medication. RNFL loss was more pronounced in the first year after glaucoma surgery.

Trabeculectomy: Does It Have a Future?

The trabeculectomy (TRAB) procedure has undergone various modifications to increase the long-term surgical success and safety profiles. The main issues with TRAB include short and long-term complications, that are more common with the concomitant use of anti-fibrotic agents. While many surgeons have predicted the demise of trabeculectomy amidst newer non-penetrating glaucoma surgeries, it is still the gold standard procedure for patients with an advanced or rapidly progressing disease and for those patients who need very low intraocular pressures. This review article is unique in summarizing the evolution of trabeculectomy and its efficacy compared to neoteric shunt procedures while trying to predict if trabeculectomy has a future in the modern surgical world. We have compared the outcomes and complications of trabeculectomy to all the surgical procedures available to date and have tried to evolve an algorithm to help surgeons to decide on their preferred technique.

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

PRCIS

Trabeculectomy surgery reduces the intraocular pressure (IOP) more than the XEN45 implant over 3 years. There is no difference in the number of antiglaucoma medications between the two procedures. The decision to perform either trabeculectomy or XEN45 implantation must be evaluated on a case-by-case basis, taking into account the high rate of needling of the XEN45.

PURPOSE

The aim of this study was to compare the differences between the efficacy and safety of the XEN45 implant and trabeculectomy (TRAB), either alone or in combination with phacoemulsification (PHACO), in patients with open-angle glaucoma (OAG) at 36 months.

METHODS

A retrospective, single-center and comparative study conducted on OAG patients that underwent XEN45 implantation or trabeculectomy from 2016 to 2018. Patients were divided into four groups: group 1 (XEN45 alone); group 2 (XEN45+PHACO); group 3 (TRAB alone); group 4 (TRAB+PHACO). For statistical purposes, groups 1 and 2 were combined (XEN45 implant), while groups 3 and 4 were also combined (TRAB surgery). Intraocular pressure (IOP), number of antiglaucoma medications (NOAM) and adverse events were evaluated. The main outcome measure was the reduction in IOP at 36 months postoperatively.

RESULTS

One hundred and thirty-four patients (134 eyes; 63 XEN45 and 71 TRAB) were included. The mean (95% CI) IOP reduction at the end of the study follow-up was-6.3 (-11.0 to -1.6 mmHg, P=0.025, XEN45 alone),-8.9 (-11.0 to-6.8 mmHg, P<0.001, TRAB alone),-2.5 (-4.5 to -0.4 mmHg, P=0.019, XEN45+PHACO), and-5.6 (-7.7 to-3.4 mmHg, P<0.001, TRAB±PHACO). The proportion of patients achieving an IOP≥6 and≤16 mmHg without treatment at the end of the 36-month follow-up were 50.8% (32/63) in the XEN45 implant and 49.3% (35/71) in the TRAB surgery group, P=0.863. The mean number of antiglaucoma medications was significantly reduced in all the study groups. The needling rate was 19% in XEN45 versus 5.6% in the TRAB group (P=0.030), and 2.81% and 36.6% of eyes in the TRAB group presented anterior chamber (AC) flattening and hyphema, respectively.

CONCLUSIONS

Trabeculectomy surgery lowered IOP significantly more than XEN45 implant with or without phacoemulsification over 3 years and had a significantly lower need for additional needling surgery. Both procedures reduce the number of antiglaucoma medications to a similar rate. These findings are relevant to the informed consent process and patient decisions for one procedure over the other.

XEN® 63 gel stent to treat a refractory uveitic glaucoma: A case report

PURPOSE

To describe the effectiveness of the XEN^® 63 gel stent in a refractory uveitic glaucoma after failure of an Ahmed Glaucoma Valve.

CASE DESCRIPTION

We report the case of a 54-year-old man with a history of uveitic glaucoma on his left eye due to Fuchs heterochromic iridocyclitis and neovascular glaucoma after a central retinal vein occlusion. Pre-operative intraocular pressure was 30 mmHg despite a QD (once-daily) dosed bimatoprost 0.3 mg and timolol 5 mg topical medication. At week 1, the eye exam showed an intraocular pressure of 6 mmHg with a well-formed bleb, a very mild hyphema and a localized choroidal detachment. At month 1, intraocular pressure was 14 mmHg with a formed bleb. Both hyphema and choroidal detachments had resolved. After a year, intraocular pressure was 16 mmHg without any medication and the bleb was still well-formed.

CONCLUSION

The XEN^® 63 gel stent provides a good intraocular pressure reduction and can be an efficient alternative for tube and filtration surgery in refractory glaucoma. Its long-term effectiveness needs to be evaluated.

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.

Minimally Invasive Micro Sclerostomy (MIMS) Procedure: A Novel Glaucoma Filtration Procedure

PRCIS

Intermediate-term results suggest that ab interno Minimally Invasive Micro Sclerostomy (MIMS) stent-less subconjunctival filtration procedure is a promising treatment option for patients with open-angle glaucoma (OAG).

PURPOSE

MIMS is a novel ab interno, stent-less, subconjunctival filtration procedure. This study set to investigate the safety, performance, and efficacy of MIMS in OAG patients.

METHODS

Prospective, open-label, single arm clinical trial with intrasubject comparisons. Study participants were adults with OAG who were candidates for a filtration procedure. Patients were operated by a single surgeon (A.A.) in Chennai, India. Following mitomycin-C pretreatment, ab interno MIMS procedure was performed alone or combined with phacoemulsification surgery. Procedure-related complications and adverse events were assessed. Primary outcomes: patients (%) achieving an intraocular pressure (IOP) ≥5 mm Hg and ≤18 mm Hg, and an IOP reduction of >20% as compared with baseline, with or without hypotensive medications, with no need for recurrent surgery.

RESULTS

Twenty-one phacoemulsification-MIMS and 10 standalone MIMS procedures were performed. Mean age was 63.94±6.33 years. Mean duration of MIMS was 1:58±0:25 (min:s). Scleral tunnels were achieved in all cases. No device malfunctions, intraoperative complications, or serious adverse events were reported. Five (16.12%) patients presented with iris clogging 1 to 24 weeks following procedure. Two were treated with laser and 3 required trabeculectomy. Mean IOP change from baseline at 24 weeks was 47.4% (31.2 to 16.4 mm Hg, P<0.0001, n=23). The mean difference was -14.8 mm Hg (95% confidence interval: -17.6, -11.9) with no statistically significant differences between groups. Qualified success was achieved in 21 (84%), 17 (74%), and 13 (93%) after 12, 24, and 52 weeks, respectively. Complete success was achieved in 17 (68%), 13 (57%), and 8 (57%) after 12, 24, and 52 weeks, respectively.

CONCLUSIONS

The interim results suggest that MIMS procedure may be a simple and effective surgical option for early OAG patients requiring target IOP in high teens although iris clogging of incision site is the major concern with this procedure.

Microinvasive glaucoma surgery: a review and classification of implant-dependent procedures and techniques

The aim of this article is to discuss how physiology and anatomical background affect the effectiveness of implant‐dependent microinvasive glaucoma surgery (MIGS). First, we provide a micro view of aqueous outflow and tissue behaviour. Second, we review studies exploring the mechanisms of the pressure‐lowering effect of MIGS, as well as tissue behaviour during aqueous flow and tissue motion. We also describe and classify microinvasive surgical procedures and the most important types of implants, as well as their mechanisms of action, implantation techniques and efficacy. Further, we summarize the indications and surgical results presented in recent studies, providing an evidence‐based update on novel and emerging MIGS techniques for the treatment of open‐angle glaucoma. These data can help surgeons to personalize the management of glaucoma and to choose the best MIGS option for individual glaucoma patients.

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.

Standalone Implantation of 2-3 Trabecular Micro-Bypass Stents (iStent inject ± iStent) as an Alternative to Trabeculectomy for Moderate-to-Severe Glaucoma

INTRODUCTION

This retrospective consecutive study compared standalone implantation of multiple (2-3) trabecular micro-bypass stents (iStent inject ± iStent) (Multi-Stent group) vs trabeculectomy + mitomycin C (Trab group) in moderate to severe open-angle glaucoma (OAG).

METHODS

Eligible patients underwent Multi-Stent or Trab surgery from 2018 to 2020 and had at least 3-month follow-up; visual field mean deviation (VF MD) - 6 dB or worse; inadequate prior response to maximum medications ± laser procedures; and had trabeculectomy as their next planned intervention. Primary effectiveness, safety-adjusted treatment success, was defined as ≥ 20% intraocular pressure (IOP) reduction on the same or fewer medications, without clinically significant safety events (severe complications, secondary surgeries, reinterventions). Secondary effectiveness included mean IOP and medications; qualified and complete attainment of target IOP (≤ 21/18/15/12 mmHg and > 6 mmHg); health-economic and quality-of-life (QoL) measures; and 2-vs-3-stent subgroup analysis.

RESULTS

The baseline groups (n = 70 Multi-Stent/40 Trab) were similar: mean IOP (21.1 mmHg/22.3 mmHg); medications (2.87/3.10 medications); disease stage (30%/35% severe); VF MD (- 10.1 dB/- 10.4 dB); and mean last follow-up (LFU, 13.1 months/15.7 months) (all differences non-significant). Primary effectiveness: treatment success at LFU was 62.9% vs 30.0% in Multi-Stent vs Trab eyes, respectively (p = 0.001). Secondary effectiveness: At LFU in Multi-Stent vs Trab groups, respectively: mean IOP decreased by 31% to 14.2 mmHg (p < 0.001) vs by 43% to 12.5 mmHg (p < 0.001); mean medications decreased by 51% to 1.31 medications (p < 0.001) vs by 84% to 0.43 medications (p < 0.001). Multi-Stent eyes, compared to Trab eyes, had fewer visits ± reinterventions within 3 months (3.6 vs 6.1, p < 0.001); longer time to first reintervention (12.2 months vs 4.5 months, p = 0.01); fewer total reinterventions (0.26 vs 0.75, p = 0.006); and earlier lifting of postoperative restrictions (12.6 vs 32.1 days, p < 0.001). In 2-vs-3-stent analysis, there was a trend toward more 3-stent eyes achieving target IOP than 2-stent eyes. Visual fields remained stable in both Multi-Stent and Trab eyes.

CONCLUSION

Implanting 2-3 trabecular micro-bypass stents was a viable alternative to trabeculectomy for moderate-to-severe OAG, with clinically appropriate IOP/medication reductions and higher safety-adjusted treatment success vs trabeculectomy.

Trabeculectomy versus Xen gel implant for the treatment of open-angle glaucoma: a 3-year retrospective analysis

Objective

To compare the two surgical techniques in terms of efficacy, safety, and postoperative management over 36 months of follow-up.

Methods

This retrospective clinical cohort study compared the outcome of trabeculectomy surgery and Xen gel implant in patients having uncontrolled glaucoma. Patients were recruited using the following inclusion criteria: uncontrolled intraocular pressure (IOP) on maximally tolerated medical therapy, healthy conjunctiva freely mobile in the superior sector, open-angle, glaucomatous visual field damage, full follow upfollow-up of at least 36 months. Thirty-four patients were submitted to trabeculectomy and 34 to Xen gel implant. We set the lower limit at 6mmHg mm Hg and the upper limit ≤12 mm Hg for criteria A, upper limit to ≤15 mm Hg for criteria B and upper limit ≤18 mm Hg for criteria C. Criteria for success have been characterizedcharacterised according to whether or not this has been achieved without (complete success) or with IOP -lowering medications (qualified success).

Results

For all survival curves, trabeculectomy was superior to Xen gel implant. When considering complete success, the log-rank test for criteria A was statistically significant (pp=0.006), marginally significant for criteria B (pp=0.065) and not significant for criteria C (pp=0.23). When qualified success was considered, trabeculectomy was superior to Xen gel for criteria A, B, and C (pp=0.012, pp=0.033 and pp=0.025, respectively). Higher number of post-operative flat chamber and bleb leakage was observed in the trabeculectomy group.

Conclusion

Xen gel implant techniques offer a better safety profile but a lower IOP reduction compared to compared with the gold -standard technique.

Comparison of Efficacy and Safety of XEN45 Implant Versus Trabeculectomy in Asian Eyes

PRCIS

Combined phacoemulsification and trabeculectomy is able to achieve greater reduction in intraocular pressure (IOP), higher rates of complete surgical success and fewer postoperative manipulations and visits compared with combined phacoemulsification and Xen implantation in glaucomatous eyes.

PURPOSE

Our study aims to compare and understand the differences between the efficacy and safety of XEN45 implantation and trabeculectomy in Asian eyes with glaucoma.

MATERIALS AND METHODS

This was a retrospective, single-center, comparative study of consecutive patients who underwent combined phacoemulsification and trabeculectomy (Phaco-Trab) from January 2013 to June 2014 and combined phacoemulsification and XEN45 implantation (Phaco-Xen) from May 2017 to September 2018 in a tertiary Ophthalmology center in Singapore. Outcome measures included IOP, number of anti-glaucoma eyedrops, success rate, factors leading to success/failure, number of postoperative interventions and visits required, and surgical complications.

RESULTS

A total of 137 eyes (91 Phaco-Trab, 46 Phaco-Xen) were included. Phaco-Trab group had greater mean IOP reduction at all time points beyond postoperative month (POM) 1 (mean difference 2.9 to 3.8 mm Hg; P<0.05), and greater reduction in mean number of antiglaucoma eyedrops beyond POM3, thought this was not statistically significant. At POM12, complete success was achieved in 83.5% in Phaco-Trab and 52.2% of Phaco-Xen group, respectively (P<0.001). There was no significant factor associated with surgical failure, other than the difference in surgical procedure. Phaco-Trab group required fewer number of postoperative interventions (P=0.009), with only a mean of 0.1 bleb interventions required per patient, versus 1.5 in Phaco-Xen group (P<0.001). Safety profiles in both groups were comparable, with no statistically significant difference in intraoperative/postoperative complications.

CONCLUSION

Phaco-Trab has significantly higher reduction in both IOP and number of antiglaucoma medications compared with Phaco-Xen group, with greater surgical success and fewer postoperative manipulations and visits. Safety profiles were comparable.

Comparison of subconjunctival microinvasive glaucoma surgery and trabeculectomy

PURPOSE

To assess surgical success and the post-operative development of intraocular pressure between XEN45^® gelstent, Preserflo^® MicroShunt and trabeculectomy with mitomycin C.

METHODS

Data from 105 eyes from 105 patients of matched cases with refractory open-angle glaucoma, who underwent surgery between January 2019, and August 2020, were evaluated. Patients underwent either stand-alone XEN gelstent insertion with Mitomycin C, stand-alone Preserflo with Mitomycin C or trabeculectomy with Mitomycin C. The primary outcome was the proportion of complete surgical success at 6 months post-operatively (i.e. intraocular pressure between 5mmHg and 18mmHg, no revision surgery, no loss of light perception and no post-operative pharmaceutical antiglaucomatous treatment). The reduction of intraocular pressure after 6 months, the classes of antiglaucomatous medication used post-operatively, best-corrected visual acuity, spherical refractive errors and astigmatism were assessed as secondary outcomes.

RESULTS

We included 35 eyes in each group. After 6-month follow-up, complete success was 73.5% [95%-CI: 57.9%-89.2%] in the trabeculectomy group, 51.4% [95%-CI: 34.0%-68.8%] in the XEN group and 74.2% [95%-CI: 57.9%-90.5%] in the Preserflo group (p = 0.08). Regarding secondary outcomes, the reduction of intraocular pressure was 12.1 ± 7.9 mmHg in the trabeculectomy group and was thereby 5.8 [95%-CI: 2.2-9.6] mmHg greater compared with the XEN group (p < 0.001) and 4.8 [95%-CI: 0.9-8.7] mmHg higher than the Preserflo group (p = 0.01).

CONCLUSIONS

No statistically significant differences were found between trabeculectomy, XEN45^® gelstent implantation and Preserflo^® MicroShunt implantation regarding surgical success after 6 months. Yet reduction in intraocular pressure was significantly higher in the trabeculectomy group. However, all three interventions resulted in sufficiently low post-operative intraocular pressure and may therefore be considered individually for glaucoma treatment.

Implantation of XEN After Failed Trabeculectomy: an Efficient Therapy?

BACKGROUND

Trabeculectomy (TE) has been the standard procedure in glaucoma surgery for a long time. This study examined the efficacy and safety profile of XEN45 Gel Stent (XEN) after failed and/or scarred trabeculectomy.

MATERIAL AND METHODS

We analysed all files of patients, who received a XEN after insufficient TE and examined changes in intraocular pressure (IOP), IOP-lowering medication, best corrected visual acuity, visual field tests as well as the intra- and postoperative complications recorded within a 12-month follow-up period.

RESULTS

31 eyes of 28 patients were analysed in our study (mean age: 66,2 ± 13,4 years; 39% female; 48% right eye; mean follow-up after TE: 70,3 ± 64,9 months). The mean IOP decreased from 23,5 ± 6,5 to 18,0 ± 5,3 mmHg (- 23,5% compared to baseline-IOP; p = 0,01) while the mean IOP-lowering medication could be reduced from 2,8 ± 1,1 to 1,1 ± 1,5 (p < 0,01) 12 months after XEN-implantation. The mean visual acuity did not change significantly (pre-op: 0,5 ± 0,6 logMAR; 12 months post-op: 0,5 ± 0,6 logMAR). The most common complications postoperatively were choroideal detachment due to postoperative hypotony in 4 eyes (13%), a needling procedure in 9 eyes (29%), a Re-XEN-Implantation in 4 eyes (13%), an open revision of the conjunctiva in 3 eyes (10%), and a Re-TE in 1 eye (3%) as well as an Ahmed-Valve implantation in 2 eyes (6%). Overall, neither needling procedure nor further glaucoma surgery was necessary in 19 eyes (61%). In 10 of 22 evaluable eyes (45%) an IOP reduction of > 20% was achieved 12 months after XEN implantation.

CONCLUSION

XEN could be an effective method to reduce IOP after failed TE. The rate of complications seems to be low and the rate of needling procedures and/or revisions is acceptable.

XEN-Augmented Deep Sclerectomy: Step-by-step Description of a Novel Surgical Technique for the Management of Open-angle Glaucoma

AIM AND BACKGROUND

The present case report describes a novel surgical technique combining XEN gel stent implantation and deep sclerectomy: XEN-augmented deep sclerectomy (XEN-DS).

CASE DESCRIPTION

An active 96-year-old Caucasian woman suffering from pseudoexfoliative glaucoma (PEXG) presented with intraocular pressure (IOP) of 24 mm Hg and a double arcuate visual field defect [mean deviation (MD) -9.6 dB] in her only functional eye despite maximal medical therapy. Considering (1) the magnitude of IOP reduction sought, (2) the risk of complications associated with trabeculectomies and glaucoma drainage devices, and (3) the risk of missed appointments due to the patient's personal and social circumstances, it was decided to tailor the surgical treatment to this patient's specific characteristics combining two existing surgical techniques. Following conjunctival dissection, a superficial scleral flap was lifted 2 mm more posteriorly than in conventional DS, and a XEN gel stent was implanted ab externo through the anterior wall of the deep sclerectomy, into the anterior chamber. A mitomycin C-soaked autologous space maintainer was used. No peri- or postoperative complications were observed. Following XEN-DS, her IOP stabilized between 5 mm Hg and 8 mm Hg through 6 months, and her visual field MD improved to -1.5 dB.

DISCUSSION

The present case report is a proof of concept for this novel surgical technique, confirming that XEN-DS has the potential to achieve substantial and persistent IOP reductions in PEXG with a satisfactory safety profile. Clinical studies are warranted to confirm these results.

HOW TO CITE THIS ARTICLE

Niegowski LJ, Gillmann K, Baumgartner JM. XEN-Augmented Deep Sclerectomy: Step-by-step Description of a Novel Surgical Technique for the Management of Open-angle Glaucoma. J Curr Glaucoma Pract 2021;15(3):144-148.

24-month outcomes of XEN45 gel implant versus trabeculectomy in primary glaucoma

PURPOSE

To compare the efficacy and safety profiles of XEN implant versus trabeculectomy as a surgical intervention for primary glaucoma.

METHODS

A retrospective cohort study of mild to moderate stage glaucoma patients, who had undergone either XEN implantation or trabeculectomy with adjunctive mitomycin C, was performed in a tertiary eye center.

RESULTS

Fifty-seven eyes for XEN implant and 57 eyes for trabeculectomy with medically uncontrolled glaucoma were included. Preoperative IOP was 16-33 mmHg. Visual field mean deviation was -9.11±6.93 dB in XEN group, and -9.67±5.06 dB in trabeculectomy group (p = 0.195). At the 24-month timepoint, mean IOP was reduced from 21.6±4.0 to 14.6±3.5 mmHg (32.4% reduction) in the XEN group (p<0.001), and from 22.5±5.8 to 12.5±4.1 mmHg (44.4% reduction) in the trabeculectomy group (p<0.001). Final IOP in XEN was significantly higher than trabeculectomy (p = 0.008) with lesser mean IOP percentage reduction at month 24 (p = 0.045). Mean number of medications was reduced from 2.2±1.4 to 0.5±0.7 in XEN group (p<0.001), and from 2.4±0.7 to 0.8±1.3 in trabeculectomy group (p<0.001). Final number of medications was not different between the groups (p = 0.225). Surgical success was comparable between XEN and trabeculectomy group. Overall success was 71.4% vs. 73.3% (p = 0.850), and complete success was 62.9% vs. 62.2% (p = 0.954), respectively. XEN had lower rate of numerical hypotony than trabeculectomy. No serious complication occurred in either procedure group.

CONCLUSION

At 24 months, XEN showed a rate of success comparable to that of trabeculectomy. Although XEN had a higher final IOP than trabeculectomy, XEN achieved 32% IOP reduction, and achieved final IOP in mid-teen level. No serious complication occurred in either group. XEN can be applied for treatment of mild to moderate stages of glaucoma in Southeast Asian patients.

XEN Glaucoma Implant for the Management of Operated Uncontrolled Glaucoma: Results and Complications during a Long-Term Follow-Up

This study aimed to analyze the surgical and refractive outcomes of XEN glaucoma implant (Allergan, an Abbvie company, Irvine, CA, USA), a minimally invasive surgical device for the treatment of operated uncontrolled glaucoma. Eyes that received XEN Gel Stent placement from December 2014 to October 2019 were retrospectively investigated. Intraocular pressure (IOP) change, best-corrected visual acuity (BCVA), change in glaucoma medications, frequency of slit lamp revision procedures, and frequency of secondary glaucoma surgeries were the primary outcomes. Seventy-two eyes of 72 subjects were included in the study: 32 (44%) men and 40 (56%) women. The follow-up period ranged from 1 to 50 months (median, 26.13 months). The mean IOP before surgery was 24.82 ± 8.03 mmHg and decreased to 17.45 ± 5.84 mmHg at the end of the study (mean difference [MD] = −7.48, 95% confidence interval [CI]: −10.04, −4.93; p < 0.001). The mean decrease from baseline was 23%. BCVA before surgery was 0.38 ± 0.30, and that at the end of the follow-up period improved to 0.47 ± 0.37, MD = 0.09, 95% CI: 0.04, 0.13; p < 0.001. Additional procedures (fluorouracil injection and bleb needling) were performed in 11/72 patients (15%). Further glaucoma surgery was necessary for 23.9% of the patients. XEN Gel Stent implantation is both safe and reasonably effective for lowering IOP in operated uncontrolled glaucoma patients.

A Comparison of Clinical Outcomes After XEN Gel Stent and EX-PRESS Glaucoma Drainage Device Implantation

PRECIS

Although the XEN stent offers a lower risk of hypotony and choroidal effusions with fewer clinic visits postoperatively, its surgical success rate was inferior to the EX-PRESS shunt.

PURPOSE

To compare the clinical efficacy and safety outcomes of the XEN stent and EX-PRESS glaucoma drainage device in glaucomatous eyes.

MATERIALS AND METHODS

One hundred eyes from 88 patients underwent ab interno XEN stent or EX-PRESS shunt implantation (52 XEN and 48 EX-PRESS) for uncontrolled glaucoma at the University of Colorado Eye Center. The primary outcome was surgical success defined as intraocular pressure (IOP) ≥6 and ≤18 mm Hg, without reoperation for uncontrolled glaucoma, loss of light perception, or use of glaucoma medications (complete success). Secondary outcomes were the same requirements allowing for medications (qualified success), mean IOP, medication use, adverse events, and number of postoperative clinic visits in the first 3 months.

RESULTS

Baseline characteristics including glaucoma type and severity were similar between groups, with the exception of XEN patients having fewer men (17% vs. 46%), older patients (median age, 78 vs. 68), and a higher percentage of white patients (89% vs. 69%). Adjusted hazard ratio of failure of XEN relative to EX-PRESS was 3.94 (95% confidence interval, 1.73-9.00, P=0.001) for complete success and 1.61 (95% confidence interval, 0.40-6.38, P=0.501) for qualified success. There were significantly fewer postoperative clinic visits during the first 3 months in the XEN group (5.3 vs. 9.1 visits, P<0.001). The incidence of serous choroidal effusions and hypotony was significantly less after XEN compared with EX-PRESS (1 vs. 9, P=0.02 and 15 vs. 25, P=0.023, respectively). Three XEN stents (5.8%) required removal.

CONCLUSIONS

In this population, although the XEN stent offers a better safety profile and fewer postoperative clinic visits, complete surgical success was inferior to the EX-PRESS shunt.

Trabeculectomy in Staphyloma Eye with High Intraocular Pressure Following Ocular Trauma – A Case Report

BACKGROUND: Ocular trauma may alter the anterior segment condition that may lead to secondary glaucomas such as inflammation, hyphema, angle recession, and lens subluxation. One of the most common procedures to decrease intraocular pressure (IOP) is trabeculectomy by creating pathways that allow aqueous humor to flow out of the anterior chamber. Scleral tissue destruction can cause damage in thin areas (such as posterior to the rectus muscle insertions) as in case of scleritis. CASE REPORT: An 11-year-old boy presented to the Ophthalmology Department of Universitas Sumatera Utara Hospital with a bigger white grayish mass and blurry vision. There was a history of the left ocular trauma 6 years ago, followed by redness of the eye, but not treated properly. On the general examination, the patient’s left eyes looked cloudy. On ocular examination, the left eye visual acuity was 1/300 and IOP was 28 mmHg. Segment anterior examination showed staphyloma from 9 to 12 o’clock, conjunctival injection, corneal scar, shallow anterior chamber, and cloudy lens. We could not asses the posterior segment due to cloudy media. We gave anti-glaucoma medication for 1 month, but the IOP did not decrease. We performed a trabeculectomy to control IOP and to prevent staphyloma from getting bigger. CONCLUSION: Trabeculectomy was an effective procedure to control IOP in a staphyloma eye following ocular trauma.

Efficacy and safety data for the Ab interno XEN45 gel stent implant at 3 Years: A retrospective analysis

PURPOSE

To report efficacy and safety measures of the XEN45 gel stent at 36 months in the UK National Health Service setting.

METHODS

Retrospective non-comparative audit of the records of patients who underwent XEN45 implantation between June 2015 and May 2017 was performed. Main outcome measures were intraocular pressure and number of antihypertensive medications used. Failure was defined as need for further surgery or stent removal. Success was defined as a 20% decrease in intraocular pressure without the need for additional glaucoma medications or a reduction in antihypertensive medications without an increase in baseline intraocular pressure. Needling rates and preoperative factors effect were assessed.

RESULTS

The cohort included 205 patients (205 eyes) with primary open angle glaucoma (84.4%), angle closure glaucoma (7.8%), or refractory glaucoma (7.8%), 62.9% had a stand-alone procedure and 37.1%, a combined phaco-XEN45 procedure. Mean intraocular pressure was 22.6 ± 7.0 mmHg at baseline compared to 14.7 ± 3.8 mmHg at 24 months and 14.0 ± 2.9 mmHg at 36 months (p < 0.001 for both). Mean number of medications used was 2.6 ± 1.1 at baseline compared to 0.5 ± 0.9 and 0.6 ± 1.0, at 24- and 36-months, respectively (p < 0.001 for both). The failure rate at 36 months was 25%. Needling was required in 36.6%. Evaluation of background factors yielded an increased failure rate in non-Caucasians compared to Caucasians (74% vs 21%, p < 0.001).

CONCLUSION

XEN45 implantation is effective and safe at 36 months' follow-up. Patients should be advised regarding the risk of failure and possible need for bleb revisions. Careful patient selection may be required.

Choroidal Detachment after XEN Gel Stent Implantation

Background

The purpose of this study is to estimate the incidence of choroidal detachment (CD) after XEN gel stent implant surgery and to evaluate the associated factors.

Methods

We reviewed the clinical charts of 126 patients who underwent XEN implantation between March 1, 2016, and December 31, 2018 at the University Eye Clinic of Genoa. Ocular, demographics, and perioperative factor were registered and analysed. Univariate and multivariate logistic analysis were performed to investigate factors associated with CD occurrence.

Results

Of the 126 patients, 25 (19.8%) developed a choroidal detachment after XEN gel stent implant surgery. The mean period between surgery and CD detection was 5.84 ± 1.77 days. The mean intraocular pressure (IOP) at the time of CD diagnosis was 6.4 ± 3.1 mmHg. Age (OR = 1.10, p < 0.019), early postoperative IOP (OR = 0.70, p < 0.001), and number of preoperative IOP-lowering drugs (OR = 5.70, p < 0.001) were significantly associated with CD presence. Complete resolution was observed in all the cases. Wide-field imaging and ultrasonography were useful tools to diagnose and follow up CD until resolution.

Conclusions

When carefully investigated, CD is a relatively common complication after XEN gel stent implant procedure. Older age, lower postoperative IOP, and higher number of preoperative IOP-lowering drugs were significantly associated with the development of CD.