XEN Implantation Research Articles

Efficacy and Safety Outcomes of XEN Implantation and Gonioscopy-assisted Transluminal Trabeculotomy for the Management of Advanced Open-angle Glaucoma.

Minimally invasive glaucoma surgery (MIGS) is not typically used in patients with advanced-stage glaucoma. This study describes the outcomes and complications of patients with advanced open-angle glaucoma (OAG) who underwent XEN implantation with cataract surgery or gonioscopy-assisted transluminal trabeculotomy (GATT) with cataract surgery. This retrospective study identified patients who had undergone XEN implantation or GATT for the management of advanced OAG. Outcomes included surgical success, intraocular pressure (IOP) reduction, number of topical IOP-lowering drops, visual field mean deviation (MD), best-corrected visual acuity (BCVA), and complications. Surgical success was defined as an IOP of <14 mm Hg and a 20% reduction at 12 months without topical IOP-lowering drops (complete success) or with topical IOP-lowering drops (qualified success). Exactly 70 eyes were enrolled in this study, including 35 who had undergone XEN implantation and 35 who had undergone GATT. The overall surgical success rate was 74.3% (26 of 35) for eyes that underwent XEN implantation and 71.4% (25 of 35) for eyes that underwent GATT. Percent IOP reduction from baseline to 12 months postoperatively was 48% in the XEN cohort and 32% in the GATT cohort. Significant reduction in the use of topical IOP-lowering drops was demonstrated for both XEN (3.26 ± 1.15-1.23 ± 1.28) (p < 0.001) and GATT (2.46 ± 1.12-0.43 ± 0.78) (p < 0.001) cohorts at 12 months postoperatively. The only complication reported was transient hyphema, which occurred in three patients from the XEN group and four from the GATT group, and resolved spontaneously. Both XEN implantation and GATT may be safe and effective management options when treating patients with advanced OAG. However, larger sample sizes are required to make direct statistical comparisons between these techniques. In this study, XEN implantation and GATT combined with cataract surgery were each associated with favorable outcomes in patients with advanced OAG. Ruparelia S, Sharif M, Shoham-Hazon N. Efficacy and Safety Outcomes of XEN Implantation and Gonioscopy-assisted Transluminal Trabeculotomy for the Management of Advanced Open-angle Glaucoma. J Curr Glaucoma Pract 2023;17(2):63-67.

Short-Term Outcomes of Xen-45 Gel Stent Ab Interno Versus Ab Externo Transconjunctival Approaches.

Ab externo transconjunctival placement of the Xen-45 gel stent offers a faster surgical approach and more rapid visual recovery with similar pressure-lowering and complication rates when compared with implantation by the ab interno approach. Compare outcomes of closed conjunctival Xen-45 implantation techniques: ab interno versus ab externo transconjunctival. Single-center, retrospective study of 70 patients undergoing Xen-45 implantation between 2017 and 2020. Group 1 (n=29) had ab interno placement, Group 2 (n=41) had transconjunctival ab externo placement. Primary outcome measures were intraocular pressure (IOP) and medication use. Secondary measures were bleb revision rates, surgical time, time to return to baseline visual acuity, and complication rates. Group 1, preoperative IOP was 22.8±7.5mmHg on 3.8±0.9 IOP-lowering medications and the postoperative IOP at last follow-up was 11.6±2.8mmHg on 1.6±1.3 medications. Group 2, preoperative IOP was 25.6mmHg±7.8mmHg on 3.7±1.1 medications and the postoperative IOP at last follow-up was 12.4±3.6mmHg on 1.5±1.3 medications. There was no difference in postoperative IOP or medications between the 2 groups ( P <0.05). The average surgical time for Group 2 was 25±6.5 minutes to 37±7.3 minutes for Group 1 ( P <0.001). Group 2 showed 88% of patients returning to baseline visual acuity at week 2 compared with 66% in Group 1 ( P <0.05). Bleb revision rates, failure rates, and complication rates were comparable between both groups ( P >0.05). IOP, medication use, complications, bleb revision rates, and failure rates were similar between ab interno and ab externo transconjunctival approaches. The ab externo group had faster surgical times and postoperative visual recovery despite higher number of patients with previous glaucoma procedures.

Bleb morphology using optical coherence tomography : After primary implantation of XEN gel stent and open conjunctival revision

The implantation of a XEN gel stent is an innovative method for filtration surgery using an ab interno approach. The morphological evaluation of the resulting bleb is decisive for surgical success. Bleb revision is frequently needed after XEN implantation and might affect the bleb morphology. Aim of this study was to examine bleb morphology using anterior segment OCT (AS-OCT) and analyze the morphological differences of blebs after primary XEN implantation and after bleb revision. Included were eyes that underwent XEN implantation (Pr-X) or bleb revision after XEN (Re‑X group). An AS-OCT of blebs was performed and images were classified using a novel classification system (the Jenaer bleb grading system, JBGS). Frequency of different tomographic patterns (M) and their correlation with intraocular pressure (IOP) were analyzed. A total of 69eyes (40in the Pr‑X and 29in the Re‑X groups) were included. At the conjunctival level, the most commonM in both groups was subconjunctival spaces (M-C2) followed by intraconjunctival cysts (C1) and no conjunctival changes (C0). No differences of frequencies between the two groups or of IOP between the three Ms were seen. At the tenon level, the most commonly seen Ms in the Pr‑X group were hyporeflective and cavernous changes (M-T2, T3) followed by no changes (M0) and hyperflective changes (T1). In the Re‑X group, the M‑T1 and T2 were most commonly seen followed by T3 and T0. The M‑T2 and T3 in the Pr‑X group and the M‑T1 and T2 in the Re‑X group correlated with lower IOP. An episcleral lake (M-ES1) was seen significantly less frequently in the Pr‑X group compared with Re‑X group where it correlated with lower IOP CONCLUSION: The hyperreflective changes at the tenon level and the presence of an episcleral lake were seen more frequently following bleb revision compared with primary XEN implantation and correlated with lower IOP. The interpretation of bleb morphology using AS-OCT should only be done considering the surgical approach used.

Five-year follow-up of corneal endothelial cell density after transscleral ab interno glaucoma gel stent implantation

PurposeThis study investigates the course of the endothelial cell density over a period of 5 years after XEN45 implantation (XEN45µm, Allergan Plc., USA) with or without combined cataract surgery.MethodsThis is a prospective, cross-sectional, monocentric, non-randomized clinical trial with the intention to treat a population of the University Eye Clinic Glaucoma Service Salzburg. One hundred and fifty-five eyes with preoperative central corneal endothelial cell counts were subjected to XEN45 implantation with (combined surgery group) or without (solo surgery group) combined cataract surgery. Endothelial cell density was measured at 3 corneal positions. XEN45 location parameters were determined with anterior segment OCT and gonioscopy.ResultsIn the combined surgery group, a significant reduction of central endothelial cell count was found at years 2 and 4 when compared to baseline (p = 0.001 and p = 0.02, n = 86), whereas at years 1, 3, and 5, no change was detected (all p > 0.09). The median reduction of endothelial cell count was − 79 (95% CI: − 183 to − 9) and − 93 (95% CI: − 220 to 23) cells at years 2 and 4, respectively. In the solo surgery group (n = 69), no significant change in endothelial cell counts was detected at any time during the 5-year evaluation period (all p > 0.07). Explorative data analyses revealed that XEN45 location parameters did not significantly influence the course of endothelial cell count over time.ConclusionsEndothelial cell loss after XEN45 implantation seems to be low. The present data suggest no impact on the position of the implant with regard to central endothelial cell counts in this study.

Effectiveness of Microinvasive Glaucoma Surgery in the United States: Intelligent Research in Sight Registry Analysis 2013–2019

To evaluate the effectiveness of microinvasive glaucoma surgery (MIGS) with and without concurrent phacoemulsification. Multicenter, retrospective cohort study. Patients in the Intelligent Research in Sight (IRIS®) Registry who underwent Xen gel stent (ab interno) implantation, endoscopic cyclophotocoagulation (ECP), or goniotomy or canaloplasty from 2013 through2019. Kaplan-Meier survival analysis was used to assess reoperation rates. We defined reoperation as any subsequent glaucoma surgery occurring 1 month to 3 years after the initial procedure. Multivariable Cox proportional hazard models were used to determine factors predictive of reoperation. Reoperation rate, mean intraocular pressure (IOP) and visual acuity (VA), postoperative complications, predictors of reoperation, and reoperation procedure type. A total of 79 363 eyes from 57 561 patients were included, with 15 118 eyes (19%) receiving stand-alone MIGS and 64 245 eyes (81%) receiving MIGS concurrent with phacoemulsification. Overall, patients who underwent MIGS concurrently with phacoemulsification showed lower reoperation rates compared with stand-alone MIGS, most pronounced in ECP and goniotomy or canaloplasty. At postoperative year 2, the cumulative reoperation rate for stand-alone procedures was 15% for ECP, 24% for Xen implantation, and 24% for goniotomy or canaloplasty compared with 3% for ECP, 19% for Xen implantation, and 6% for goniotomy or canaloplasty concurrent with phacoemulsification (P < 0.001 for each stand-alone MIGS vs. MIGS with phacoemulsification). Black race, older age, moderate and severe glaucoma, higher baseline IOP, and glaucoma subtype were associated with higher reoperation risk. Although IOP decreased in all groups, stand-alone MIGS showed a more substantial decrease in mean IOP. Complication rates from MIGS were low overall: 1% for ECP, 1% for Xen implantation, and 2% for goniotomy or canaloplasty. In current United States clinical practice, MIGS has substantially lower reoperation rates when performed with phacoemulsification, especially for ECP and goniotomy or canaloplasty. Approximately one-sixth of patients undergoing stand-alone ECP and one-quarter of patients undergoing stand-alone Xen implantation or goniotomy or canaloplasty require reoperation by 2 years. Black race, diagnosis coding of moderate to severe glaucoma, and higher baseline IOP were associated with higher risk of reoperation after MIGS procedures. Proprietary or commercial disclosure may be found after the references.

Impact of Fellowship Training on Practice Patterns of Glaucoma Surgeons Treating Medicare fee-for-service Beneficiaries

ABSTRACT Purpose Analyze practice patterns of glaucoma surgeons with and without fellowship training. Materials and Methods Physician-specific 2017 Medicare data were obtained from the Centers for Medicare & Medicaid Services website. Current Procedural Terminology codes identified procedures including iStent, tube shunts, trabeculectomy, complicated trabeculectomy, endoscopic cyclophotocoagulation, internal Xen Implant, external Xen or Express shunt, Gonioscopy-Assisted Transluminal Trabeculotomy, and Kahook Dual Blade Goniotomy. Physicians with fellowship training were identified via the American Glaucoma Society website. Results A total of 1547 glaucoma surgeons were identified, of which 319 had completed fellowship training. Overall, fellowship-trained glaucoma surgeons performed more services (50.4 ± 47.0 vs 40.5 ± 35.3, P < .001) with a larger variety of procedures (1.8 ± 1.0 vs 1.3 ± 0.6, P < .001) than those without fellowship training. Surgeons without fellowship training were more likely to perform iStent and endoscopic cyclophotocoagulation and less likely to perform the remaining procedures than their fellowship-trained counterparts. Medicare payments did not differ between groups and the number of Medicare beneficiaries only differed for internal Xen implant (P = .03). Patient comorbidity burden was similar between groups with about one-third of patients being diagnosed with ischemic heart disease. Conclusions Surgeons without fellowship training can treat a similar volume of glaucoma patients as those with fellowship training. However, based on surgical procedures employed, their practices are skewed towards mild and moderate glaucoma and they are more limited in their breadth of procedures. In addition, ischemic heart disease was prevalent in the glaucoma patient population.

Italian Candidates for the XEN Implant: An Overview from the Glaucoma Treatment Registry (XEN-GTR).

Background The Italian XEN Glaucoma Treatment Registry (XEN-GTR) was created to acquire a comprehensive prospective dataset that includes the patient characteristics, intraoperative variables, and postoperative management of glaucoma patients undergoing the XEN gel stent implantation. Methods This was a prospective observational, longitudinal clinical study involving 10 centres throughout Italy. The baseline examination included a comprehensive evaluation of demographic parameters (age, sex, ethnicity, and systemic condition), specific ophthalmological parameters, and quality of life questionnaire score collection. Results The baseline data of 273 patients were analysed. The median (IQR) age was 72 (65.0 to 78.0) years. Of the 273 patients, 123 (45%) were female and 150 (55%) were male. A total of 86% of the patients had open-angle glaucoma with a mean intraocular pressure of 24 ± 6 (range 12.0–60.0) mmHg. The mean number of medications was 2.7 ± 0.9 at baseline for the patients with a prevalence of prostaglandin analogues combined with a beta-blocker and anhydrase carbonic inhibitor (31.8%). The mean scores of the NEI-VFQ 25 and GSS questionnaires were 78 ± 18 (range 26.5–100) and 85 ± 14 (range 79–93), respectively. Combined XEN/cataract surgeries were scheduled in 73.7% of the patients. The preferred place for the XEN implant was the supero-nasal quadrant (91.6%). Conclusions Observing the baseline characteristics of the typical Italian candidates for the XEN gel implant shows that they are patients affected by POAG and cataracts, with moderate to severe glaucoma damage, all of which has an impact on their quality of life.

Two-year Outcomes of XEN Implantation with Minimal Bleb Needling.

AimOur study aims to report the 2 years outcomes of the XEN implant in a single unit, single surgeon setting with minimal bleb needling.MethodsA 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.ResultsAt 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%.ConclusionIt 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 SignificanceBleb 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 articleAli 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.

3-Year Outcomes of XEN Implant Compared With Trabeculectomy, With or Without Phacoemulsification for Open Angle Glaucoma.

Trabeculectomy (TRAB) 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 2 procedures. The decision to perform either TRAB or XEN45 implantation must be evaluated on a case-by-case basis, taking into account the high rate of needling of the XEN45. The aim of this study was to compare the differences between the efficacy and safety of the XEN45 implant and TRAB, either alone or in combination with phacoemulsification (PHACO), in patients with open angle glaucoma (OAG) at 36 months. A retrospective, single-center and comparative study conducted on OAG patients who underwent XEN45 implantation or TRAB from 2016 to 2018. Patients were divided into 4 groups: group 1 (XEN45 alone), group 2 (XEN45+PHACO), group 3 (TRAB alone), and group 4 (TRAB+PHACO). For statistical purposes, groups 1 and 2 were combined (XEN45 implant), whereas groups 3 and 4 were also combined (TRAB surgery). IOP, number of glaucoma medications, and adverse events were evaluated. The main outcome measure was the reduction in IOP at 36 months postoperatively. One hundred thirty-four patients (134 eyes; 63 XEN45 and 71 TRAB) were included. The mean (95% confidence interval) IOP reduction at the end of the study follow-up was -6.3 (-11.0 to -1.6 mm Hg, P =0.025, XEN45 alone), -8.9 (-11.0 to -6.8 mm Hg, P <0.001, TRAB alone), -2.5 (-4.5 to -0.4 mm Hg, P =0.019, XEN45+PHACO), and -5.6 (-7.7 to -3.4 mm Hg, P <0.001, TRAB±PHACO). The proportion of patients achieving an IOP≥6 and ≤16 mm Hg 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 glaucoma 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 flattening and hyphema, respectively. TRAB 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 reduced glaucoma medications to a similar rate. These findings are relevant to the informed consent process and patient decisions for one procedure over the other.

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

BackgroundXen 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.MethodsWe 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.ResultsWe 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.ConclusionOur 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.

Transconjunctival XEN45 Implantation for Glaucoma Performed at the Slit Lamp: A Pilot Study.

Précis:This pilot study of ab externo implantation of a gel microstent is a novel, minimally invasive glaucoma surgery performed at the slit lamp that is effective for lowering intraocular pressure in patients with uncontrolled glaucoma.Purpose:To evaluate the intraocular pressure (IOP)–lowering effect of gel microstent (XEN Gel Stent, Allergan, Irvine, CA) implantation using an ab externo approach in an office setting.Patients and Methods:This retrospective, multicenter chart review examined outcomes in patients with uncontrolled glaucoma receiving maximally tolerated medical therapy, who underwent slit lamp ab externo gel stent implantation. At postoperative visit, the IOP, the number of glaucoma medications, the final position of the stent, and the needling rate were analyzed. Assessments were conducted 1 day, 1 week and 1, 3, 6, and 12 months after the implantation. Treatment success was defined as IOP ≥6 mm Hg and ≤18 mm Hg with ≥20% reduction from presurgical IOP, with or without medications.Results:Thirty-four eyes from 28 patients were included. Mean preoperative IOP was 24.1±8.0 mm Hg on 3.2±0.9 glaucoma medications. At 12 months postoperative, IOP was reduced to 15.4±4.7 mm Hg on 0.6±1.0 medications; 46.9% and 81.3% of eyes achieved complete and partial success, respectively. The gel stent was properly positioned in 94.1% of eyes after 1 attempt at implantation and in 100% of eyes after a second attempt. In addition to malpositioning, observed complications included occlusion, erosion, and endophthalmitis following anterior chamber reformation. Adjunctive needling was required in 21% of implanted eyes.Conclusion:Slit-lamp-based transconjunctival XEN45 implantation reduced intraocular pressure in glaucoma patients in the first year of this pilot study and was most commonly associated with wound leak and hypotony among other adverse events.

Ab-externo XEN gel stent implantation in primary open-angle glaucoma: 6-month follow-up

Purpose: XEN gel stent (XGS) is one of the minimally invasive glaucoma surgery (MIGS) procedures offering substantial intraocular pressure (IOP)-lowering. We evaluated the efficacy and safety of XGS implantation via an ab externo approach in patients with primary open-angle glaucoma (POAG). We present 13 cases of successful XEN implantation via an ab externo approach in these patients.Study design: Retrospective case series.Methods: This was a retrospective case series involving patients diagnosed with POAG at a tertiary referral centre who underwent XGS implantation between February 2019 and June 2020 for uncontrolled IOP despite maximum topical medications. All patients underwent XGS implantation via an ab externo approach placed at the superotemporal quadrant. The main outcome measure was IOP reduction and number of antiglaucoma medications after XGS implantation, postoperative procedures, and surgical complications.Results: Thirteen eyes of 13 patients were included in the analysis. At the 6-month follow-up, mean IOP reduction was 2.73 ± 3.66 mmHg and mean IOP was 13.8 ± 1.99 mmHg on an average of 1.6 antiglaucoma medications. Complications included transient hypotony and transient IOP spikes requiring needling. Two patients required stent removal due to recurrent conjunctival erosion and stent migration into the anterior chamber.Conclusion: XGS implantation is able to achieve good IOP control with reduced need for antiglaucoma medications after a minimum follow-up of 6 months. Longer follow-up is needed to assess its long-term outcome.

Short-Term Efficacy and Safety of Open Conjunctiva Ab Externo XEN45 Gel Stent Implantation in Glaucoma Patients.

We examined the safety and efficacy of the open conjunctiva ab externo approach for XEN45 gel stent implantation. There was a significant reduction in intraocular pressure (IOP) and number of glaucoma medications at 12 months follow-up. This study aims to determine the safety and efficacy of the open conjunctiva ab externo approach to XEN45 stent implantation. Retrospective chart review of all patients between July 2018 and March 2020 who underwent XEN45 implantation. IOP and the number of glaucoma medications were measured at the preoperative, 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months postoperative appointments. The primary outcome of this study is the number of cases achieving complete success at 12 months postoperatively. Forty-four eyes of 44 patients were included. Mean preoperative IOP was 26.2±8.7mmHg on 3.2±0.7 IOP-lowering medications. At 12 months postoperative, mean IOP was 18.9±9.1mmHg (n=35, P <0.0001; mean reduction of 27.9%) on 0.9±1.4 (n=35, P <0.0001) IOP-lowering medications. Postoperative needling was performed in 5 cases (11.4%). Of the 35 cases with a postoperative visit at 12 months, complete success was achieved in 14 cases (40.0%) and qualified success in 3 cases (8.6%). Eighteen cases (51.4%) were recorded as failures at 12 months, comprised of 4 cases requiring reoperation for glaucoma (2 XEN45 implants, 1 trabeculectomy, and 1 Baerveldt implant), and 14 cases that did not meet the IOP-lowering criteria for success. During the postoperative course, there was 1 case of self-limited hypotony, 2 self-resolving choroidal effusions, and 3 cases of bleb leakage. The open conjunctiva ab externo approach to XEN45 implantation achieved successful levels of IOP reduction in 48.6% of glaucoma cases within the first year. The most common adverse events included the need for additional glaucoma surgery (excluding needling procedures), transient hypotony, and bleb leak.

Anterior Segment-Optical Coherence Tomography Bleb Morphology Comparison in Minimally Invasive Glaucoma Surgery: XEN Gel Stent vs. PreserFlo MicroShunt.

Background: The purpose of this study is to compare the morphology of six-month follow-up blebs created by a subconjunctival glaucoma surgical device (XEN45) to those created by a PreserFlo MicroShunt with a sub-Tenon insertion, utilizing AS-OCT. Methods: A retrospective study of 29 eyes who underwent XEN45 implantation and 29 eyes who underwent PreserFlo MicroShunt implantation. The patients were analyzed at 24 h, 1 week, 1 month, 3 months and 6 months. At each visit, the maturation and morphological alterations of the blebs were observed, as well as connections with the IOP. Results: In both groups, IOP showed significant reduction at all follow ups (p < 0.0001). In XEN group, the most common bleb morphology in the immediate postoperative was the subconjuntival separation type (42%) followed by the uniform type (34%), with a trend inversion at 6 month follow up (51% of uniform type). On the contrary, the most common morphology after PreserFlo was the multiple internal layer (55%), which showed a tendency to reduce over time and was substituted by the microcystic multiform, whose percentage increased over time (17% at day 1 vs. 44% at month 6). Uniform appearance was associated by the posterior episcleral fluid (PEF) lake presence. Both horizontal and vertical diameters significantly increased over time. Conclusion: XEN and PreserFlo implantation resulted in the production of diffuse blebs with different characteristics, which may influence IOP lowering capacity and bleb revisions necessity over time.

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

Several new implant devices have recently been introduced to glaucoma surgery using various techniques for reducing intraocular pressure (IOP). Two implants introduced during the past couple of years, XEN45 and PreserFlo Microshunt, are both designed to control subconjunctival filtration. There are two Swiss multicenter studies that collected the data retrospectively to analyze the efficacy and safety of these two devices separately. In this study, we report the analysis of the combined data subset from the University Hospital of Basel. The XEN45 implantation technique was introduced to Basel University Hospital in 2016 and PreserFlo Microshunt in 2018. Sixty operated patients, thirty in each group, were operated on by one surgeon, clinically followed up, and their data retrospectively analyzed from medical records. Only standalone procedures, without combined phacoemulsification, were considered in this analysis; the lens status, however, was neither an inclusion nor an exclusion criterion. Further inclusion criteria were the diagnosis of open-angle glaucoma, no previous glaucoma surgery, other than laser trabeculoplasty, and complete medical records during the 12 months of follow-up. IOP reduction during a 12-month postoperative period was the primary outcome measure as well as the number of IOP reducing drugs. The number of subsequent surgical interventions and complications/adverse events are descriptively reported. Patient age, gender, ophthalmological diagnosis, and initial preoperative IOP were well balanced between the two groups. Postoperative IOP course was comparable between the two methods for the first 12 months. IOP measurements were taken preoperatively and then on the first postop day, week 1, month 1, and months 3, 6, and 12 for the PreserFlo Microshunt vs. XEN45 (mmHg): 23.6 vs. 24.9, 9.0 vs. 8.9, 11.4 vs. 10.6, 13.0 vs.18.3, 16.8 vs.15.1, 15.9 vs.15.0, and 15.4 vs.14.5, respectively. IOP reducing medications were also comparable between the two groups. The study showed that subsequent interventions were more frequent in the XEN45 (13) than in the PreserFlo Microshunt group (7). Both methods demonstrate satisfactory IOP control within a 12-month postoperative period with practically no serious adverse events/complications, but with relatively high numbers of subsequent interventions (needlings), particularly in the XEN45 group.

Complications and post-operative interventions in XEN45 gel stent implantation in the treatment of open angle glaucoma-a systematic review and meta-analysis.

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). 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. 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. 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.

Two-Year Outcome of Surgery in Glaucoma Patients.

To evaluate the 2-year surgical treatment outcome in glaucoma patients. A retrospective, single-center, interventional study was performed on 160 eyes of 125 patients suffering glaucoma, including POAG (82 eyes), pseudoexfoliation (PEX) (59eyes), pigment dispersion (8 eyes), and secondary glaucoma (2 eyes). Eyes with uncontrolled intraocular pressure (IOP) or signs of glaucoma progression despite medical treatment were included to undergo either trabeculectomy (TE), XEN implantation, combined TE with phacoemulsification (TE + IOL), or XEN implantation with phacoemulsification surgery (XEN + IOL). Primary efficacy outcome was the mean IOP reduction. Secondary outcome was the mean reduction in the number of medications. The data were compared at baseline vs.1 day, 1 week, and 1, 3, 6, 12, and 24 months following surgery. For statistical evaluation, ANOVA-based linear mixed-effects models were performed with SPSS. The mean IOP reduction in a 2-year follow-up was 30.31% (22.17 vs. 15.45 mmHg, p < 0.001). The mean number of antiglaucoma medications was reduced from 2.87 to 0.58 (p = 0.001), where TE alone or combined surgeries seemed to be more effective than isolated XEN surgery. Transient IOP hypotony on the first postoperative day occurred in PEX patients following TE surgery (p = 0.024). At 6 months, PEX patients with isolated XEN surgery showed a transient IOP increase, whereas those after combined TE + IOL surgery showed the lowest IOP within the PEX group compared to other glaucoma patients (p < 0.026). After 2 years, all performed glaucoma surgeries achieved a significant reduction in IOP and the number of antiglaucoma medications.

Impact of Primary Needling on the XEN Implant Clinical Outcomes: A Real-Life Retrospective Study.

PurposeTo assess the effectiveness and safety of primary-needling in eyes who underwent a XEN45 implant.MethodsRetrospective and single center study. Consecutive patients with early-to-moderate open-angle glaucoma (OAG) or ocular hypertension, who underwent XEN45 surgery, either alone or combined with phacoemulsification, and had at least a valid 12-month post-operative visit, were included in the study. Primary needling was performed by using a 30-gauge needle without viscoelastic. Subjects were divided in two groups: Eyes who underwent XEN+primary-needling (needling) and those who underwent XEN without primary-needling (no-needling). The primary end-point was the mean change in IOP from baseline to the last follow-up visit.ResultsSixty-three eyes, 19 (30.2%) in the needling group and 44 (69.8%) in the no-needling one, were included in the study. There were not significant differences in mean IOP lowering between needling and no-needling groups at month-12 (mean difference −2.5±5.3 mm Hg, p=0.0926). No significant differences in mean reduction of ocular-hypotensive medications were observed between needling and no-needling groups, p=0.8690. At month-12, 50 (80.6%) had blebs considered as functioning, with no difference between groups, p = 0.5631. At month-12, 59 (93.7%) eyes were classified as success, with no significant differences between needling (17/19) and no-needling (42/44) groups, p=0.3754. Secondary needling was performed in 8 (12.7%) eyes, without differences between groups (p=0.6333).ConclusionPrimary needling, at the time of surgery, was a safe procedure in OAG patients who underwent a XEN implant, although it was not associated with a lower postoperative IOP or less ocular hypotensive medications.

The Outcomes of XEN Gel Stent Implantation: A Systematic Review and Meta-Analysis

PurposeXEN 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.MethodsWe 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.ResultsFive 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%.ConclusionsXEN 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.

Treatment results of standalone XEN-45 implantation in patients with primary and secondary open-angle glaucoma

Treatment results of standalone XEN-45 implantation in patients with primary and secondary open-angle glaucoma