Prospective Evaluation of XEN Gel Implant in Eyes With Pseudoexfoliative Glaucoma:

PRESERFLO™ Microshunt: 1-Year Results of a 25-Gauge vs. 27-Gauge Needle Tract

Background: The purpose of this study was to evaluate the effectiveness and safety of the PreserFlo™ microshunt (PMS) using a 25-Gauge vs. 27-Gauge needle tract. Methods: This is a prospective postoperative examination of 60 glaucoma eyes that received a PMS. The main outcome measures were intraocular pressure (IOP), glaucoma drug score (GDS), Kaplan-Meier success rates, complications, and secondary intervention rates. Two subgroups were formed for data comparison: 27-Gauge (27G), and 25-Gauge (25G). Success was defined as IOP < 18 mmHg together with ≥20% IOP reduction with medication allowed (qualified success = QS18) or not (full success = FS18). Results: IOP and GDS were reduced from baseline to the 1-year study visit as follows: All eyes from 23.4 ± 8.6 mmHg (3.1 ± 0.9) to 15.1 ± 5.9 mmHg (0.8 ± 1.1); 25G from 24.2 ± 7.3 mmHg (3.0 ± 0.8) to 12.7 ± 2.7 mmHg (0.5 ± 0.8); and 27G from 23.1 ± 9.2 mmHg (3.1 ± 1.0) to 16.2 ± 6.7 mmHg (0.9 ± 1.2). IOP at one year was lower in the 25G group compared to the 27G group (p = 0.035). Bleb needling was required in eight (13.3%) eyes and open bleb revisions in three (5.0%). Transient hypotony occurred in 21% and choroidal effusion in 8% of all eyes. Choroidal effusions were more frequent in the 25G group (21%) compared to the 27G group (2%, p = 0.031). One-year success rates were significantly higher in the 25G group compared to the 27G group for both QS18 (25G: 67.9% vs. 27G: 35.7%, p = 0.002) and FS18 (25G: 63.6% vs. 27G: 29.2%, p = 0.007). Conclusions: The PreserFlo microshunt is an effective and safe glaucoma surgery with a low rate of bleb revisions or needlings. We show that the 25G needle tract might be more efficient for IOP control at the cost of increased IOP-related complications compared to 27G.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Surgical outcomes of excisional goniotomy using the kahook dual blade in severe and refractory glaucoma: 12-month results

OBJECTIVES

To describe the efficacy and safety of goniotomy with trabecular meshwork excision using the Kahook Dual Blade (KDB, New World Medical Inc., Rancho Cucamonga, CA) in patients with severe or refractory glaucoma.

METHODS

This retrospective multicentre case series reports on 40 eyes with severe or refractory open-angle glaucoma that underwent standalone or combined KDB goniotomy and were followed for 12 months post-operatively in the United-States, Mexico and Switzerland. Surgical success was defined as an intraocular pressure (IOP) reduction ≥20% from baseline at 12 months, with fewer medications than preoperatively. Mean IOP and antiglaucoma medication reduction, probabilities of achieving an IOP ≤16 or 18 mmHg, and adverse events were also analysed.

RESULTS

Mean IOP decreased from 18.1 ± 5.0 mmHg at baseline to 14.8 ± 3.7 mmHg at 12 months (18.2% reduction, P < 0.001). Concomitantly, the mean number of glaucoma medications decreased from 2.5 ± 1.4 to 1.7 ± 1.2 (32% reduction, P = 0.002). The proportion of eyes achieving an IOP reduction of more than 20% from baseline was 37.5% (n = 15) at 12 months. At 12 months, 67.5% and 82.5% achieved a medicated IOP ≤ 16 and ≤18 mmHg, respectively. No severe complications were reported.

CONCLUSION

Excisional goniotomy with KDB achieves a statistically significant IOP and antiglaucoma medication reduction in severe or refractory glaucoma over a period of 12 months. While its efficacy decreases with time, its favourable safety profile makes it a potentially useful primary or adjunctive procedure in high-risk eyes.

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.

Two-year Outcomes of XEN Implantation with Minimal Bleb Needling

Aim

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

Methods

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

Results

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

Conclusion

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

Clinical Significance

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

How to cite this article

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

Outcomes of Deep Sclerectomy following Failed XEN Gel Stent Implantation in Open-Angle Glaucoma: A Prospective Study

Background: The purpose of this study is to evaluate the outcome of deep sclerectomy (DS) as a secondary procedure following failed ab-interno XEN gel stent implantation in patients with open-angle glaucoma. Methods: Prospective, single-center, non-randomized, interventional study. Consecutive eyes that underwent mitomycin C (MMC) augmented XEN gel stent surgery, with uncontrolled intraocular pressure (IOP) or signs of disease progression, were included to undergo MMC-augmented DS. Primary efficacy outcome was surgical success, defined as complete when the unmedicated IOP was 12 mmHg or less, or 15 mmHg or less and 20% lower than at the timing of XEN failure and defined as qualified when the IOP fulfilled the same conditions with fewer medications than before deep sclerectomy. Secondary measures were mean reduction in IOP and in the number of medications, and the rates of complications. Results: Seventeen eyes were enrolled with a mean age of 72.1 ± 8.2 years (66.7% women). The mean follow-up was 20.1 ± 4.9 months, with more than 12-month data available from 15 eyes. Following DS, IOP decreased significantly from 22.6 ± 5.3 mmHg to 12.3 ± 5.5 (45.6%; p < 0.001). Antiglaucoma medications dropped from 1.1 ± 0.9 to 0.3 ± 0.7. Complete success was obtained in 40% of eyes using the threshold of 12 mmHg or less and a 20% decrease of IOP, and in 60% using the 15 mmHg or less threshold. Adverse events were observed in 20% of eyes (bleb leakage (13.3%); hypotony (6.7%)). No cases of choroidal detachment or hypotony maculopathy were reported. Conclusions: Failed XEN gel stent implantation does not seem to negatively affect the safety and efficacy of subsequent deep sclerectomy surgery.

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

Background

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

Methods

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

Results

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

Conclusion

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

Supplementary Information

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

Canaloplasty in Pseudoexfoliation Glaucoma. Can It Still Be Considered a Good Choice?

Purpose: The aim of this study was to assess the long-term outcomes of canaloplasty surgery in pseudoexfoliation glaucoma (PEXG) patients. Material and Methods: A total of 116 PEXG patients with an intraocular pressure (IOP) > 21 mm/Hg and maximum tolerated local medical therapy who underwent canaloplasty from February 2008 to January 2022 were considered. Every six months, all subjects underwent a complete ophthalmic examination. The period of follow-up ranged from 2 to 167 months. Inclusion criteria included only patients for whom the entire procedure could be completed with a follow-up of at least 2 years. Results: Amongst the 116 PEXG patients, the entire procedure could not be performed in 10 eyes (8.6%), and thus they were not considered in the analysis. Twenty-three patients did not reach the two-year follow-up and another 16 patients during this time period were lost. A total of 67 patients with a mean follow-up of 49 ± 32.3 months were considered in the analysis. The pre-operative mean IOP was 31.2 ± 8.7 mm/Hg (range 20−60). The mean IOP at the two-year follow-up was 17.2 ± 6.7 mmHg, with a mean reduction from baseline of 44.9%. After two years, the qualified success rates according to three different criteria (IOP ≤ 21, ≤18 and ≤16 mmHg) were 80.6%, 73.1% and 61.0%, respectively. The total number of medications used pre- and at the follow-up at 2 years was 3.5 ± 0.8 and 1.2 ± 1.4, respectively. Early complications included: hyphema, in about 30% of cases; Descemet membrane detachment (4.9%); and IOP spikes > 10 mmHg (9.7%). A late failure with an acute IOP rise of up to 50 mmHg was observed in 41 cases (61.2%) after 3 to 72 months. Conclusions: Long-term post-operative outcomes of canaloplasty in PEXG patients appear to be quite good on average; however, an acute rise in IOP can be observed in more than 60% of the cases after a long period of satisfactory IOP control. For this reason, canaloplasty may not be suitable in eyes with PEXG, especially in patients with severe functional damage.

Ultrastructural analysis of explanted CyPass microstents and correlation with clinical findings

Purpose

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

Methods

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

Results

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

Conclusion

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

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.

Preliminary results of Preserflo Microshunt versus Preserflo Microshunt and Ologen implantation

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

One-year outcomes of microshunt implantation in pseudoexfoliation glaucoma

PURPOSE

To compare the safety and efficacy of microshunt implantation augmented with Mitomycin C in patients with pseudoexfoliation glaucoma (PEXG) and primary open-angle glaucoma (POAG).

METHODS

In this retrospective, single centre, interventional study, 46 eyes of 41 patients with PEXG (20 eyes) and POAG (26 eyes) underwent microshunt implantation. Definition of failure was an intraocular pressure (IOP) lower than 5 or higher than 17mmHg on two consecutive visits, an IOP reduction lower than 20% on two consecutive visits, the need of surgical revisions or reoperations or loss of light perception. Outcome was rated as complete success if achieved without medication, otherwise as qualified success. Furthermore, postoperative complications and interventions were compared between the two groups.

RESULTS

Patient demographics were similar, except for older age in the PEXG group (70.9±8.6 versus 77.6±8; p = 0.02). Mean IOP dropped from 21.5±5.8mmHg (PEXG) and 18.2±4.5mmHg (POAG) at baseline to 12.8±3.0mmHg (p<0.0001) and 12.9±4.2mmHg (p<0.0001), respectively, at one year. Mean number of medications were reduced from 2.8±1.3 to 0.3±0.8 for PEXG patients (p<0.0001) and from 2.7±1.3 to 0.3±0.8 for POAG patients (p<0.0001). At one year of follow-up 75.0% of PEXG patients achieved complete success and 80.0% qualified success. In the POAG group rates were 73.1% and 76.9%, respectively. Postoperative complications were comparable between both groups, except for higher rates of hypotony (p = 0.04) and choroidal detachment (p = 0.03) in the PEXG group.

CONCLUSION

Microshunt implantation demonstrated similar efficacy results in PEXG and POAG eyes at a follow-up of 12 months. Higher rates of transient hypotony and choroidal detachment were observed in PEXG eyes.

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.

Minimally Invasive Glaucoma Surgery: A Critical Appraisal of the Literature

Micro- or minimally invasive glaucoma surgeries (MIGS) have been the latest addition to the glaucoma surgical treatment paradigm. This term refers not to a single surgery, but rather to a group of distinct procedures and devices that aim to decrease intraocular pressure. Broadly, MIGS can be categorized into surgeries that increase the trabecular outflow [Trabectome, iStent (first and second generations), Hydrus microstent, Kahook Dual Blade and gonioscopy-assisted transluminal trabeculotomy], surgeries that increase suprachoroidal outflow (Cypass microstent and iStent Supra), and conjunctival bleb-forming procedures (Xen gel stent and InnFocus microshunt). Compared to traditional glaucoma surgeries, such as trabeculectomy and glaucoma drainage device implantation (Ahmed, Baerveldt, and Molteno valves), MIGS are touted to have less severe complications and shorter surgical time. MIGS represent an evolving field, and the efficacy and complications of each procedure should be considered independently, giving more importance to high-quality and longer-term studies.

Outcomes of XEN45 gel stent using posterior small incision sub-tenon ab interno insertion (Semi-open) technique

PURPOSE

To evaluate the 12-month outcomes of a novel posterior small incision sub-tenon ab interno technique of XEN stent insertion ('Semi-open').

METHOD

Consecutive eyes underwent XEN stent insertion with the Semi-open technique by two surgeons between 1st July 2018 and 30th September 2019. All cases received subconjunctival injection of 0.1 mL of mitomycin C 0.2 mg/mL. Eyes with primary open angle glaucoma (OAG), secondary OAG or pseudophakic primary angle closure glaucoma (PACG) were included. Exclusion criteria were phakic PACG, uveitic or neovascular glaucoma and postoperative follow-up <12 months. Primary outcomes were defined by World Glaucoma Association guidelines. Secondary outcomes included change in glaucoma medications, needling rates and complications.

RESULTS

We included 37 consecutive eyes of 35 patients with primary OAG (n = 30), secondary OAG (n = 6) and pseudophakic PACG (n = 1). Thirty-one eyes (84%) received a standalone XEN implantation and 6 (16%) underwent XEN implantation combined with phacoemulsification. The IOP reduced from 19.6 ± 6.0 mmHg preoperatively to 11.2 ± 2.6 mmHg at 12 months (P < 0.01). The number of glaucoma agents reduced from 3.49 ± 1.14 preoperatively to 1.57 ± 1.36 at 12 months. At 12 months, qualified success was 97.3% and complete success was 32%, with one case requiring trabeculectomy. Needling was required in 19% of cases over the 12 month follow up. Complications included 19 cases of transient hypotony and 7 cases of transient choroidal effusion. There were no cases of exposure, bleb leak or bleb-related infection.

CONCLUSION

Semi-open XEN technique achieves high surgical success rate in the medium-term with relatively low post-operative bleb needling rate.

Needling and open filtering bleb revision after XEN-45 implantation-a retrospective outcome comparison

Purpose

To compare efficacy and safety of needling and open bleb revision after XEN-45 surgery.

Methods

This retrospective study represents real-life data of patients who underwent XEN-45 surgery between November 2014 and June 2018 in the Vienna General Hospital. The following groups were formed for data evaluation: (PSEA) primary surgery secondary intervention allowed (n = 268); (PS) primary surgery until secondary intervention (n = 268); (N) first needling until additional secondary intervention (n = 55); (BR) first bleb revision until additional secondary intervention (n = 105). Main outcome measures were pre- and postoperative intraocular pressure (IOP), number of glaucoma medication (GM), Kaplan–Meier success rates, and secondary intervention rates. Success was defined as postoperative IOP < 21 mmHg and < 18 mmHg together with ≥ 20% IOP reduction with medication allowed.

Results

IOP (and GM) was lowered from 23.5 ± 8.0 (GM 3.1 ± 1.0) to 14.9 ± 8.2 mmHg (1.2 ± 1.4) in group PSEA and 18.1 ± 8.2 mmHg (1.5 ± 1.4) in group PS, in group N from 23.2 ± 10.1 (1.5 ± 1.0) to 19.3 ± 8.5 mmHg (2.2 ± 1.3) and in group BR from 22.0 ± 8.0 mmHg (2.5 ± 1.1) to 15.5 ± 6.4 mmHg (1.3 ± 1.5) after a median follow-up of 16.0, 8.4, 4.8, and 7.3 months, respectively. Success rates at 1 year were significantly higher in group BR (50.7%) compared to PS (37.7%, p = 0.019) and N (24.3%; p = 0.015). An additional intervention was required less frequently in group BR (17.1%) compared to group PS (49.6%, p < 0.001) and group N (54.5%, p < 0.001).

Conclusion

Our data appear to indicate favorable outcomes for open XEN bleb revision in terms of Kaplan–Meier success rates and secondary intervention rate compared to the needling procedure.

XEN® Gel Stent compared to PRESERFLO™ MicroShunt implantation for primary open-angle glaucoma: two-year results

Purpose

To evaluate the long‐term efficacy and safety of two minimally invasive glaucoma surgery implants with a subconjunctival drainage approach: the XEN45 Gel Stent^® (Xen) implant and the PRESERFLO™ MicroShunt (MicroShunt).

Methods

Retrospective comparative case series of primary open‐angle glaucoma (POAG) patients with at least 6 months of follow‐up after a MicroShunt or Xen implantation augmented with mitomycin C.

Results

Forty‐one eyes of 31 patients underwent Xen implantation, and 41 eyes of 33 patients, MicroShunt implantation. Baseline characteristics were similar, except for more combined surgeries with phacoemulsification in the Xen group (37% vs. 2%). Mean baseline IOP ± standard deviation dropped from 19.2 ± 4.4 to 13.8 ± 3.8 mmHg (n = 26) in the Xen group and from 20.1 ± 5.0 to 12.1 ± 3.5 (n = 14) in the MicroShunt group at 24 months of follow‐up (p = 0.19, t‐test). The number of IOP‐lowering medications dropped from 2.5 ± 1.4 to 0.9 ± 1.2 in the Xen group and from 2.3 ± 1.5 to 0.7 ± 1.1 in the MicroShunt group. The probability of qualified success was 73% and 79% at 24 months of follow‐up for the Xen and MicroShunt groups, respectively. Postoperative complications were usually mild and self‐limiting. The number of bleb needling and secondary glaucoma surgery procedures was similar in both groups; however, in the Xen group more additional MicroPulse^® transscleral cyclophotocoagulation procedures were performed.

Conclusion

Xen Gel Stent and PreserFlo MicroShunt implantations achieved comparable results in POAG eyes in terms of IOP‐lowering and surgical success, with a similar high safety profile.

Effects of Ab Interno XEN Gel Implantation on Postural Intraocular Pressure Elevations

Purpose: The aim of this study was to analyze the postural intraocular pressure (IOP) changes in open-angle glaucoma after ab interno XEN gel implant surgery and to compare them with the changes observed with trabeculectomy and medical treatment.Patients and Methods: The study sample included 18 patients with XEN gel implants, 30 patients who had trabeculectomy, and 30 medically managed glaucoma patients. All patients in XEN gel implant and trabeculectomy groups had at least 11 months of follow-up and had successful surgeries that resulted in medication-free control of IOP. A rebound tonometer (Icare, Finland Oy, Helsinki, Finland) was used to measure the IOP levels at the sitting, supine, and dependent lateral decubitus (DLDP) positions after a 5-minute rest at each position.Results: In all the groups, the mean IOP values in the DLDP and supine positions were significantly higher than the sitting position. The IOP elevation after moving from sitting to supine position was significantly reduced in XEN gel implant and trabeculectomy groups compared to medical treatment group (p = .001 and p = .002, respectively). The IOP elevation after a moving from sitting to DLDP was also significantly reduced in XEN gel implant and trabeculectomy groups compared to the medical treatment group (p = .003 and p = .01, respectively). However, there was no significant difference in IOP change after moving from sitting to supine or DLDP positions between XEN gel implant and trabeculectomy groups (p = .74 and p = .98, respectively).Conclusion: This study demonstrated that XEN gel implant could reduce postural elevations in IOP to the same degree as trabeculectomy and provide significantly better postural IOP control than medical treatment. This surgery can be an effective minimally invasive alternative for patients with significant positional IOP elevations.

Automated Gonioscopy Assessment of XEN45 Gel Stent Angle Location After Isolated XEN or Combined Phaco-XEN Procedures: Clinical Implications

PRéCIS:: Angle location of the XEN implant both in isolated and in combined procedures did not appear to influence long-term outcomes. However, more posterior stent placements seem to be associated with increased early postoperative complications.

PURPOSE

The purpose of this study was to assess success and safety outcomes of different levels of insertion of the XEN45 gel stent in the angle in standalone and combined procedures.

METHODS

This was a cross-sectional study of patients in whom XEN had been implanted without intraoperative gonioscopy. Automated gonioscopy was used for postoperative analysis of the XEN location, classified as anterior or posterior relative to the scleral spur. Absolute success was defined as ≥20% intraocular pressure decrease from baseline and ranging from 6 to 21 mm Hg without medication and qualified success if medicated. The need for additional drainage surgery was considered failure, but needling was allowed. Clinical data were retrieved from patient files.

RESULTS

Gonioscopy-assisted XEN location was performed on 42 eyes of 33 patients (14 isolated and 28 combined procedures) on average 18±9 months after surgery. Absolute (32% vs. 35%; P>0.99) and qualified (44% vs. 65%; P=0.22) success was similar in both anterior and posterior placements, respectively. Kaplan-Meier survival analysis yielded similar median survival times for both groups. The distribution of XEN insertion level in the angle was similar in standalone and combined procedures (P=0.75). Although overall safety outcome measures did not differ significantly, the proportion of intraoperative and early postoperative complications was higher in posterior XEN placements (P=0.03).

CONCLUSIONS

Different locations of XEN45 did not seem to significantly impact late success and safety outcomes, although stents inserted more posteriorly may be associated with a higher rate of early complications. Combined implantation of XEN with phacoemulsification does not seem to influence stent location in the iridocorneal angle in a setting without intraoperative gonioscopy.

Results of fluorouracil-augmented Xen45 implantation in primary open-angle and pseudoexfoliation glaucoma

PURPOSE

To report the effectiveness and safety of 5-fluorouracil (5-FU)-augmented Xen45 implantation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PEXG).

METHODS

This single-center, retrospective chart review study included 29 eyes that underwent 5-FU-augmented Xen45 implantation. Main outcome measures were intraocular pressure (IOP) levels and number of glaucoma medications. Surgical success was defined as IOP ≤ 21 mmHg and ≥ 20% reduction from preoperative levels without (complete success) or with (qualified success) glaucoma medications and without further glaucoma surgery at last follow-up. All postoperative interventions and complications were also noted.

RESULTS

The mean age of the patients was 67.5 ± 10.3 years, and the mean follow-up time was 23.2 ± 12.6 months. Mean IOP was 24.5 ± 8.7 mmHg and decreased by 30.2% at 12 months, 24.9% at 24 months, and 31.7% at final visit (p < 0.001, p = 0.006, p > 0.001, respectively). Mean number of glaucoma medications decreased from 2.83 preoperatively to 0.71 at 12 months, 0.87 at 24 months, and 0.86 at final visit (p < 0.001). At final visit, the complete success rate was 48.3%, qualified success rate was 69%, and 62.1% of the eyes were free of glaucoma medications. Needling was performed in 7 eyes (24%). Adverse events included choroidal detachment in 5 eyes, hyphema in 2 eyes, and endophthalmitis in 1 eye.

CONCLUSION

5-FU-augmented Xen45 implantation in POAG and PEXG patients provided safe and effective IOP lowering with significant reduction of glaucoma medications up to 3 years.

Learning Curve and One-Year Outcome of XEN 45 Gel Stent Implantation in a Swedish Population

Purpose

Evaluation of 1-year-outcome of XEN 45 gel stent surgery in a Swedish cohort with regard to clinical success, complications, and learning curve.

Patients and Methods

This was a retrospective study of glaucoma patients undergoing glaucoma XEN-stent surgery alone or combined with phacoemulsification between December 2015 and May 2017. Intraocular pressure (IOP), number of medical agents, and adverse events were assessed. Clinical success rate was defined as achieving individual target pressure with/without medication.

Results

A total of 113 eyes were included in the final statistics. Mean age was 70.8±11.8 years. Primary open angle glaucoma (POAG) accounted for 46.9% and exfoliative glaucoma (PEXG) for 40.7%. Mean preoperative IOP was 23.8±6.2 mmHg and mean number of agents 3.4. After 1 year, mean IOP was reduced to 16.1±4.7 mmHg and medication to 1.34 substances on average. Failure rate at 1-year follow-up was 34% with no significant difference between POAG and PEXG. There was a trend of higher success rate for combined cases (P=0.116). Stents with malpositioned or curved appearance had significantly worse outcome. The failure rate of the most productive surgeon dropped from 33% to 10% from the first implantations. Temporary hypotony (19.5%) and choroidal detachment (9.7%) were the most common complications. Blockage of the inner stent lumen was common (8.8%), with a high proportion of failure.

Conclusion

XEN-stent surgery is a surgical option in uncontrolled glaucoma in both POAG and PEXG. A XEN-stent can reduce both IOP and the number of antiglaucoma medications needed. The learning curve is significant and stent positioning is crucial for optimal results. Combined XEN-cataract surgery is not inferior to stand-alone procedures. The long-time effectiveness is still to be proven.

Management of Anticoagulation and Antiplatelet Therapy in Glaucoma Surgery

The use of antithrombotic therapy is rising as the population of older adults grows and novel agents with wider indications emerge. Likewise, surgical treatment of glaucoma may become increasingly common as the prevalence of glaucoma increases and innovative treatment options are developed. These trends highlight the need to understand how best to manage antithrombotic therapy in the context of glaucoma surgery. This review article describes current literature on antithrombotic therapy and perioperative thromboembolic risk evaluation based on individual factors. In addition, guidance is offered on the management of antithrombotic therapy in the setting of each type of glaucoma surgery, with an emphasis on a multidisciplinary approach involving the patients' treating physicians.

Impact of Phacoemulsification Combined with XEN Gel Stent Implantation on Corneal Endothelial Cell Density: 2-Year Results

INTRODUCTION

Corneal integrity has long been a preoccupation of glaucoma surgeons considering glaucoma drainage device surgery or antimetabolite-enhanced trabeculectomy. Despite having demonstrated a good safety profile and significant intraocular pressure-lowering capacities, the impact of XEN gel stents on endothelial density was never specifically investigated. The purpose of this study is to assess the effect of XEN gel stents on central endothelial cell density (ECD) over 24 months. To achieve this, we compared the effect on ECD of combined XEN surgery with that of a standard phacoemulsification procedure.

METHODS

This was an investigator-initiated, retrospective study, conducted at a single tertiary glaucoma center. Patients with primary or secondary open-angle glaucoma who underwent XEN implantation combined with phacoemulsification between January 2015 and June 2016 were retrospectively enrolled. Patients who had undergone standalone phacoemulsification over the same period of time were enrolled to form the control group of this comparative study. The primary outcome measure was the ECD. Patients who had undergone standalone XEN implantation and patients for whom both a baseline and 24-month ECD could not be obtained were excluded from the analysis. Percentages of ECD reductions were calculated for each studied eye, and the mean of ECD reductions was calculated for each group as well as for subgroups.

RESULTS

Thirty-two eyes of 23 patients (mean age=76.0±7.9 y, 60% female) underwent standalone phacoemulsification (n=15) or combined XEN surgery (n=17) and had an ECD both at baseline and 24-month postoperatively. Mean baseline ECDs were 2568±491 versus 2379±335 cells/mm, respectively (P=0.21). In the combined XEN surgery group, 58.8% of eyes (n=10) required at least 1 mitomycin C (MMC)-enhanced needling revision to maintain their target intraocular pressure. In the standalone phacoemulsification group, ECD decreased by a mean 14.5%, from 2567.7±491.2 to 2196.1±591.9 cell/mm (P=0.072). In the combined XEN surgery group, ECD decreased by a mean 14.3%, from 2378.8±334.7 to 2039.6±451.1 cell/mm (P=0.018). The difference in percentage reduction of ECD between the 2 groups was not statistically significant (P=0.226). Within the combined XEN surgery group, the ECD decreased by a mean of 15.4% in patients who did not undergo needling revisions and by 13.1% in patients who underwent the MMC-augmented procedure (P=0.485). In the 3 patients who underwent >1 needling revision, a 21.3% reduction in ECD was observed, but the difference was not statistically significant (P=0.653). Neither the time of the first needling (P=0.452), the patients' age (P=0.285), or sex (P=0.308) was statistically associated with ECD loss.

DISCUSSION

The present study demonstrated that the XEN gel implant combined with phacoemulsification produces 24-month ECD loss of a similar magnitude to that observed following standalone phacoemulsification. MMC-augmented needling revisions do not appear to have an impact on ECD.

XEN® Gel Stent: A Comprehensive Review on Its Use as a Treatment Option for Refractory Glaucoma

The XEN Gel Microstent is a subconjunctival microinvasive glaucoma surgical device developed with the aim of improving the predictability and safety profile of bleb-forming glaucoma surgical procedures. The stent is a hydrophilic tube composed of a porcine gel cross-linked with glutaraldehyde with good stability and biocompatibility with minimal tissue reaction. This device has demonstrated promising outcomes with fewer risks compared to traditional surgeries. The aim of the review is to present early studies on different designs of the XEN Gel Stent, to summarize different surgical techniques of implantation and to analyze more comprehensively the results, complications and rates of needling of the commercially available device (Xen 45). The review will address separately special cases (PXG, UVG, ICE, congenital glaucoma) and describe small series and case reports.

XEN Gel Stent to Treat ICE Syndrome: 4 Cases

PRéCIS:: This case series reports safe, effective implantation of XEN gel stents to treat iridocorneal endothelial (ICE) syndrome. The stents continue to function well and have not been occluded by membranes or peripheral anterior synechiae, but continued follow-up is necessary.

PURPOSE

ICE syndrome-related glaucoma is often refractory to medical treatment, and traditional surgical treatment has lower success rates than typical for other types of glaucoma. We present a series of patients who were treated with XEN gel stent implantation.

PATIENTS AND METHODS

Retrospective case series of 4 patients with ICE syndrome who underwent XEN with subconjunctival mitomycin C injection.

RESULTS

Average preoperative intraocular pressure was 28.5 mm Hg on 3.8 glaucoma medications, and average postoperative intraocular pressure was 10.5 mm Hg on 1.0 medication. No patients required return to the operating room for additional procedures over an average of 6.9 months of follow-up. One patient had shallow anterior chamber that resolved with conservative management. Another had shallow anterior chamber that resolved with anterior chamber reformation with viscoelastic and developed nonappositional choroidal effusions that had resolved at most recent follow-up of 7 months after surgery. No XEN implants have been occluded by membrane formation or peripheral anterior synechiae.

CONCLUSIONS

XEN is a safe and effective option for surgical management of ICE syndrome-related glaucoma. Further follow-up surveillance is necessary.

Twelve-month outcomes of an ab interno gelatin stent combined with cataract surgery or as a standalone procedure in pseudophakic eyes with open-angle glaucoma

PURPOSE

To provide safety and effectiveness outcomes at 12 months postsurgery for an ab interno transscleral gelatin stent in patients with advanced refractory glaucoma or intolerant of medical therapy.

SETTING

Multisubspecialty ophthalmology practice and surgery center.

DESIGN

Retrospective, single-arm, cohort study.

METHODS

All patients implanted with the gelatin stent either combined with cataract surgery or as a solo procedure between February 2017 and April 2018 and meeting eligibility criteria were included. Outcome measures included proportion of patients achieving a 20% reduction in intraocular pressure (IOP), proportions at or below 12 mm Hg, 15 mm Hg, and 18 mm Hg, IOP, medication usage, needling rate, and adverse events.

RESULTS

The study included 92 eyes of 69 patients. Mean preoperative IOP and medications were 16.6 mm Hg on 2.1 medications. Average visual field mean deviation was -13.7 dB. Half (48%) of the patients achieved the primary endpoint of 20% reduction while medication use decreased by -1.7 medications. Most patients at 12 months had IOP of 18 mm Hg or less on zero medications (74%), whereas 34% were medication free and had IOP of 12 mm Hg or less. Bleb needling was required for only 14% of patients. There were few adverse events (13% of eyes), the most common being corrected distance visual acuity loss and hyphema.

CONCLUSIONS

Eyes with advanced glaucoma despite maximum tolerated medical therapy achieved lower target IOP on fewer medications after implantation with the gelatin microstent.

XEN-augmented Baerveldt drainage device implantation in refractory glaucoma: 1-year outcomes

PURPOSE

To evaluate outcomes of XEN-augmented Baerveldt drainage device implantation in refractory glaucoma and factors predicting surgical success.

METHOD

All eyes undergoing XEN-augmented Baerveldt for refractory open-angle glaucoma at a tertiary glaucoma centre between January 2016 and November 2017 were retrospectively enrolled. Intraocular pressure (IOP), number of anti-glaucomatous medications and postoperative adverse events (AEs) were analysed for 1 year postoperatively. Surgical success was defined as achieving (1) an IOP ≤ 15 mmHg or (2) ≤ 18 mmHg, with or without (qualified) or without medications (complete). Any subsequent glaucoma surgery was considered failure.

RESULTS

Out of 60 eyes enrolled, 12-month data were available for 41 eyes (71.4%). Mean age was 64.7 ± 23.1 years (50% female). Following surgery, IOP decreased significantly from a baseline of 29.9 ± 13.2 to 15.2 ± 6.6 mmHg (- 49.2%; P < 0.0001) at 12 months. Anti-glaucoma medications decreased from 3.0 ± 1.3 to 1.3 ± 0.9. Complete success was achieved by 14.6% of eyes using both the ≤ 15 mmHg and the ≤ 18 mmHg thresholds, and qualified success was achieved in 43.9% and 48.8%, respectively. Throughout the follow-up period, AEs were observed in 51.2% (hypotony = 24.4%; XEN blockage = 17.1%; displacement of XEN gel stent = 4.9%; hyphema = 4.9%). The 12-month success rate was significantly higher in patients who presented an IOP ≤ 10 mmHg at 1 week (58.6%, P = 0.001). Overall, 41.5% of patients required reoperation at 12 months (58.8% revision of the surgery; 41.2% transscleral cyclodestruction).

CONCLUSION

XEN-augmented Baerveldt is a safe and moderately effective technique to reduce IOP and anti-glaucoma medications in refractory glaucoma. IOP at 1 week seems to be a predictor for surgical success. Nevertheless, a high proportion of patients requires reoperation.

Comparing Medium-Term Clinical Outcomes following XEN® 45 and XEN® 63 Device Implantation

Purpose

To evaluate medium-term clinical outcomes with XEN® 45 or XEN® 63 Gel Stent (Allergan, Dublin, Ireland) for treatment of primary open angle glaucoma (POAG). Materials and Methods. Retrospective, descriptive, and observational study involving 40 patients implanted with a XEN® 45 Gel Stent and 34 implanted with a XEN® 63 Gel Stent who had undergone POAG surgery and had been followed up and controlled between 12 and 36 months.

Results

IOP dropped from 18.02 ± 5.23 mmHg preop to 13.81 ± 1.88, 14.80 ± 2.23, and 14.62 ± 1.90 at 1, 2, and 3 years after surgery (p < 0.001) consecutively with XEN® 45 and from 19.00 ± 6.11 mmHg preop to 15.47 ± 2.45, 14.66 ± 2.45, and 15.46 ± 2.48 at 1, 2, and 3 years after surgery (p < 0.001) with XEN® 63. The number of drugs used by patients to treat their glaucoma decreased after undergoing surgery in both groups. Within the XEN® 45 group, mean changes at 1 year, 2 years, and 3 years amounted to 70%, 74.3%, and 37.5%, respectively, whereas within the XEN® 63 group, the mean reduction was 75%, 79.8%, and 71.9%. When comparing the outcomes for two groups, the differences did not prove to be statistically significant. More than 90% of the procedures included in the study (using either gel-stent device) were completed without any noteworthy complications.

Conclusion

POAG surgical procedures with either XEN® 45 or XEN® 63 Gel Stent implantation could be a safe and effective treatment approach.

Prospective Studies of Minimally Invasive Glaucoma Surgeries: Systematic Review and Quality Assessment

Glaucoma is a common blinding disease; while there is no cure, effective treatments include medications, laser, and incisional surgery. There is significant interest from patients and doctors to develop safer surgical options throughout the spectrum of disease, to minimize treatment burden in mild glaucoma patients and to minimize risk of complications in patients needing more aggressive treatment. Surgical procedures called Minimally or Micro-Invasive Glaucoma Surgery (MIGS) are growing in popularity. Eighty-seven prospective studies on MIGS were identified and assessed for quality. Most (74%) did not have a control group. Twelve of the highest quality were reviewed. MIGS procedures appeared to have fewer complications, and lowered intraocular pressure, and reduced medication use. Studies were limited by small sample size, narrow spectrum of glaucomatous disease, and/or conflicts of interest. There is a need for high quality, independently funded and performed, comparative studies on the MIGS to help make treatment decisions.

Medium-term clinical outcomes following Xen45 device implantation

PURPOSE

To evaluate medium-term clinical outcomes with microstent XEN^® 45 Gel Stent (Allergan Dublin, Ireland) for treatment of primary open-angle glaucoma (POAG).

MATERIAL AND METHODS

This is a retrospective, descriptive and observational study involving 93 eyes from 63 patients who had undergone POAG surgery with a XEN^® 45 Gel Stent implantation and had been followed up and controlled between 12 and 36 months.

RESULTS

IOP dropped from 18.23 ± 5.00 mmHg pre-op to 14.16 ± 2.14, 14.47 ± 2.16 and 14.63 ± 1.91 at 1, 2 and 3 years after surgery (p = 0.000, 0.000 and 0.001) consecutively. Mean number of medications dropped from 1.87 ± 0.94 preoperatively to 0.31 ± 0.69, 0.34 ± 0.63 and 1.00 ± 0.88 (p = 0.000, 0.000 and 0.017) at 12, 24 and 36 months. Mean visual field deviation values never turned out to be significant for any of the follow-up visit data. A total of 94.6% of the surgical procedures turned out to be complication-free. In one surgery, the procedure failed and 18 months later other device was implanted.

CONCLUSION

POAG surgical procedures with XEN^® 45 Gel Stent implants are a safe and effective treatment approach.

Two-Year Outcomes of XEN Gel Stent Surgery in Patients with Open-Angle Glaucoma

PURPOSE

To evaluate the 2-year treatment outcomes of the XEN gel stent (Allergan, Inc, Irvine, CA) in glaucoma patients.

DESIGN

Prospective, single-center interventional study.

PARTICIPANTS

One hundred forty-nine eyes of 113 patients with open-angle glaucoma.

METHODS

Consecutive eyes with uncontrolled intraocular pressure (IOP) or signs of disease progression despite medical treatment were included to undergo either standalone XEN implantation or combined XEN implantation plus phacoemulsification surgery, both with mitomycin C injections.

MAIN OUTCOME MEASURES

Primary efficacy outcome was success, defined as complete when the unmedicated IOP was 12 mmHg or less, 15 mmHg or less, or 18 mmHg or less and 20% lower than at baseline over the 2-year period and defined as qualified when the IOP fulfilled the same conditions with fewer medications than at baseline. Secondary measures were mean reduction in IOP and in the number of medications and the rates of reoperations.

RESULTS

One hundred nine eyes (84 patients; mean age, 74.3 years) underwent XEN plus phacoemulsification surgery and 40 eyes (29 patients; mean age, 74.7 years) underwent standalone XEN surgery. Overall, 129 eyes (86.6%; 96 eyes of 75 XEN plus phacoemulsification patients and 33 eyes of 24 XEN standalone surgery patients) completed the study. Mean medicated IOP was 20.0±7.5 mmHg at baseline and 14.1±3.7 mmHg at 2 years (P < 0.01), a 29.3% IOP reduction. Mean number of medications dropped from 2.0±1.3 before surgery to 0.6±0.9 at 2 years (P < 0.001). Complete success was achieved in 18.2% of eyes using the 12 mmHg or less and 20% reduction criteria and in 44.4% using the 15 mmHg or less threshold. Needling with mitomycin C was performed in 58 eyes (45%). In all, 11.4% underwent reoperations.

CONCLUSIONS

After 2 years, XEN gel stent surgery achieved a clinically and statistically significant reduction both in IOP and the number of antiglaucoma medications, while requiring a high rate of needling interventions.

Efficacy and safety of the ab interno gelatin stent in severe pseudoexfoliation glaucoma compared to non-pseudoexfoliation glaucoma at 6 months

PURPOSE

To compare the efficacy and safety of the XEN45 Gel Stent surgery between patients with and without severe pseudoexfoliation glaucoma.

METHODS

In this retrospective, single-center, comparative chart review, records of 24 eyes of 23 patients with pseudoexfoliation glaucoma and 24 eyes of 23 patients with non-pseudoexfoliation glaucoma with severe glaucoma, defined as uncontrolled intraocular pressure on maximally tolerated medical therapy, were reviewed. All patients were treated with XEN45 Gel Stent surgery, in either a standalone procedure (84.8%) or combined with phacoemulsification (15.2%). Mean intraocular pressure, mean number of intraocular pressure-lowering medications, change in best-corrected visual acuity and needling or rescue surgery rates were assessed. Success was defined as at least 20% decrease in baseline intraocular pressure among treatment-free patients.

RESULTS

Patient characteristics were similar between the groups. At 6 months, intraocular pressure in the pseudoexfoliation glaucoma group decreased by 32% (24.3 ± 9 mmHg-14.8 ± 7 mmHg, p < 0.001), with comparable decrease in intraocular pressure in the non-pseudoexfoliation glaucoma group (22.6 ± 7 mmHg-16.7 ± 6 mmHg, p = 0.011). Similar rates of patients required topical anti-glaucoma therapy (29% vs 22%, p = 0.559), needling (54% vs 37%, p = 0.247), and rescue trabeculectomy (13% in both, p = 1.00) at the last follow-up. However, intraocular pressure decreased more in the pseudoexfoliation glaucoma group among treatment-free patients (-10.1 ± 8.0 mmHg vs -4.1 ± 8.1 mmHg, p = 0.043), and final intraocular pressure was lower in the pseudoexfoliation glaucoma group (12.2 ± 3.5 mmHg vs 15.8 ± 5.7 mmHg, p = 0.044).

CONCLUSIONS

The XEN45 Gel Stent implant demonstrated similar efficacy and safety among severe pseudoexfoliation glaucoma and non-pseudoexfoliation glaucoma patients. Greater magnitude of decreased intraocular pressure occurred among treatment-free pseudoexfoliation glaucoma patients.

Two-year results of a multicenter study of the ab interno gelatin implant in medically uncontrolled primary open-angle glaucoma

PURPOSE

To evaluate the effectiveness of an ab interno subconjunctival gelatin implant as primary surgical intervention in reducing intraocular pressure (IOP) and IOP-lowering medication count in medically uncontrolled moderate primary open-angle glaucoma (POAG).

METHODS

In this prospective, non-randomized, open-label, multicenter, 2-year study, eyes with medicated baseline IOP 18-33 mmHg on 1-4 topical medications were implanted with (phaco + implant) or without (implant alone) phacoemulsification. Changes in mean IOP and medication count at months 12 (primary outcomes) and 24, clinical success rate (eyes [%] achieving ≥ 20% IOP reduction from baseline on the same or fewer medications without glaucoma-related secondary surgical intervention), intraoperative complications, and postoperative adverse events were assessed.

RESULTS

The modified intent-to-treat population included 202 eyes (of 218 implanted). Changes (standard deviation) in mean IOP and medication count from baseline were - 6.5 (5.3) mmHg and - 1.7 (1.3) at month 12 and - 6.2 (4.9) mmHg and - 1.5 (1.4) at month 24, respectively (all P < 0.001). Mean medicated baseline IOP was reduced from 21.4 (3.6) to 14.9 (4.5) mmHg at 12 months and 15.2 (4.2) mmHg at 24 months, with similar results in both treatment groups. The clinical success rate was 67.6% at 12 months and 65.8% at 24 months. Overall, 51.1 (12 months) and 44.7% (24 months) of eyes were medication-free. The implant safety profile compared favorably with that published for trabeculectomy and tube shunts.

CONCLUSIONS

The gelatin implant effectively reduced IOP and medication needs over 2 years in POAG uncontrolled medically, with an acceptable safety profile. ClinicalTrials.gov registration number: NCT02006693 (registered in the USA).