XEN Surgery Research Articles

No Changes in Keratometry Readings and Anterior Chamber Depth after XEN Gel Implantation in Patients with Glaucoma.

Background: This study aimed to compare keratometry and anterior chamber depth (ACD) changes after XEN implantation in primary open-angle glaucoma (POAG) cases over a 3-month follow-up period. Methods: Twenty patients with POAG who underwent XEN63 implantation, either standalone or combined with cataract surgery, were included. Preoperative data, including best-corrected visual acuity (BCVA), refraction, gonioscopy, ophthalmoscopy, intraocular pressure (IOP) evaluation, and axial length, were collected. Corneal topography and ACD measurements were assessed preoperatively and at postoperative days 1, 7, 15, 30, 60, and 90. Each patient's eye that underwent XEN surgery was included in the study group, with the fellow eye serving as a control. Results: In the study group, there was a significant decrease in IOP after XEN stent implantation at all investigated time intervals (p < 0.05). However, changes in mean ACD did not show statistically significant differences at any follow-up examination in both the study and control groups. Additionally, keratometry readings revealed no significant changes in total astigmatism or steep keratometry values in either group. Conclusions: XEN implantation in POAG cases resulted in a significant decrease in IOP over the 3-month follow-up period. However, there were no significant changes observed in mean ACD or keratometry readings, indicating stability in these parameters post-XEN implantation. These findings suggest that XEN implantation may be an effective option for IOP reduction without affecting corneal curvature or ACD in POAG patients.

XEN-45 in the management of early glaucoma surgery: A national Delphi consensus study

Background and objectiveRecommendations on general glaucoma management and the use of early minimally invasive and microincisional surgeries are limited. This study aimed to establish consensus regarding glaucoma management, focusing on the XEN-45 gel stent implant. MethodsA Delphi consensus-driven process was used. The scientific committee led the study, identified the expert panel, and participated in elaborating the questionnaire. Fifty-one panelists were invited to complete, on a nine-point Likert scale, an 89-item questionnaire covering three topic blocks. Two Delphi rounds were performed. Consensus was achieved if ≥66.6% of panelists reached agreement or disagreement. ResultsPanelists agreed on 84 items related to the patients’ quality of life, the therapeutic algorithm and patient profile, and surgical and pre- and post-operative management. Panelists agreed on the suitability of XEN stent implants to treat glaucoma at different stages and for different patient profiles: young patients, elderly or with significant comorbidities, and with myopic glaucoma, patients who failed previous surgeries, and with previous poor post-operative experience. XEN surgery was considered a therapeutic step prior to classic filtering surgery and a possible first surgical option in elderly patients with comorbidities and uncontrolled intraocular pressure. XEN surgery allows the patient to return to routine daily activities faster than conventional filtering surgeries and to reduce and/or eliminate topical treatments. ConclusionsThis Delphi-driven consensus resulted in a series of general recommendations for glaucoma management, including those related to patient quality of life, therapeutic algorithm, and patient profile, and specific ones regarding the use of XEN stent gel surgery.

Four-Year Outcome of XEN 45 Gel Stent Implantation in a Swedish Population.

To report the long-time success rate of XEN 45 gel stent implantation in a Scandinavian population. This was a retrospective single-center analysis of all patients undergoing XEN 45 stent surgery between December 2015 and May 2017. The main outcome was success rate according to several definitions of success. Subgroup analysis was performed. Secondary outcomes were change in intraocular pressure (IOP) and number of IOP-lowering agents. Need for secondary glaucoma surgery, needling rate and complications were recorded. A total of 103 eyes could be evaluated after four years. Mean age was 70.6 years. Primary open-angle glaucoma (POAG) accounted for 46.6% and exfoliative glaucoma (PEXG) for 39.8%. Mean IOP dropped from 24.0 to 15.9 mmHg (p<0.001) and IOP-lowering agents from 3.5 to 1.5 (p<0.001). The success rate with individual target pressures after four years was 43.7%. Secondary glaucoma surgery was performed in 45 (43.7%) of cases. Combined cases (n=12) were not statistically different to stand-alone procedures (p=0.28). No difference between PEXG and POAG could be detected (p=0.44). During the learning curve, stent misplacement was common and resulted in worse outcome for less experienced surgeons. The overall success rate of XEN 45 gel stent surgery in the present cohort is relatively low in a long-time follow-up under the given circumstances if all initial patients are included to follow-up. The influence of the surgeon's learning curve is obvious, and improvement in success can be expected when used by experienced and high-volume surgeons. No significant differences were found in PEXG compared to POAG or in XEN surgery combined with cataract surgery compared to stand-alone.

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.

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.

Bleb Analysis Using Anterior Segment Optical Coherence Tomography and Surgical Predictors of XEN Gel Stent.

PurposeTo determine the early predictors of surgical success 6 months after XEN surgery among clinical parameters, including anterior segment optical coherence tomography (AS-OCT).MethodsA total of 31 eyes with medically uncontrolled primary open-angle glaucoma or pseudoexfoliation glaucoma was enrolled retrospectively. Using AS-OCT, XEN tip location was categorized into intraconjunctival, intratenon, or uviform at day 1 and blebs were classified into no or low, high sparse, high thick, cystic, or mixed walls at month 6. Using slit-lamp photography, blebs were classified into no or low, localized avascular, diffuse avascular, localized vascular, or diffuse vascular blebs at month 6. Surgical success was defined as an intraocular pressure (IOP) of less than 14 mm Hg.ResultsIntraconjunctival and intratenon locations of the tip mostly created a high sparse wall, whereas the uviform type mostly created no or low wall and no or low bleb. The uviform type was linked to pseudoexfoliation glaucoma. A high sparse wall and diffuse avascular bleb showed a lower mean IOP than a high thick wall and localized vascular bleb. In the multivariate analysis, female sex and IOP at week 1 were early predictors of surgical success (8.45 times and 33.1% per 1 mm Hg-decrease, respectively).ConclusionsBleb evaluation using AS-OCT is valuable to correlate tip location and bleb morphology with clinical profiles, considering that a lower early postoperative IOP is linked to surgical success.Translational RelevanceBleb analysis using AS-OCT on day 1 could help to predict bleb morphology after 6 months, which is important to maintain the functioning bleb in the longer term.

Prominent lymphatic vessel in a functioning bleb after repeat XEN gel stent implantation surgery in pseudoexfoliative glaucoma: a case report

XEN gel stent implantation (XEN) surgery is becoming more popular due to its safety profile and efficacy, with conjunctival lymphatics thought to be critical in maintaining bleb drainage. We are reporting the case of a 75-year-old man with right eye pseudoexfoliative glaucoma who had two previous episodes of failed XEN surgery despite given needling and antimetabolite. He had a repeat XEN surgery in our center and his intraocular pressure was under control at the time of writing without any topical glaucoma medication, needling, nor antimetabolite. On examination, there was presence of prominent, dilated, and irregular lymphatic vessel originating from the distal end of the bleb. Anterior segment optical coherence tomography identified the lymphatic vessel located in the superficial Tenon’s layer, which is most likely an initial lymphatic but larger in diameter. This dilated lymphatic vessel may be an important factor for his currently successful filtration surgery.

Standalone XEN45 Gel Stent implantation versus combined XEN45-phacoemulsification in the treatment of open angle glaucoma-a systematic review and meta-analysis.

The XEN45 Gel Stent is currently the only FDA-approved sub-conjunctival minimally invasive glaucoma surgery (MIGS) procedure. It has been used worldwide either as a standalone implantation procedure or in combination with phacoemulsification surgery. Concomitant phacoemulsification is understood to influence outcomes of traditional subconjunctival filtering surgery. However, the comparative efficacy between standalone XEN45 Gel Sent implantation ("Standalone XEN45") and combined XEN-phacoemulsification surgery ("XEN45-Phaco") remains unclear. This study aims to appraise current literature to compare the efficacy of Standalone XEN45 and XEN45-Phaco in open-angle glaucoma. A comprehensive search of PubMed, CINAHL, CENTRAL databases was performed with the terms "Xen surgery" followed by selective vetting. Pilot, cohort, observational studies and randomised controlled trials that included at least 10 patients undergoing either Standalone XEN45 or XEN45-Phaco surgeries for the treatment of open-angle glaucoma were deemed eligible for inclusion after independent assessment by 2 authors. The search workflow was reported according to the PRISMA guidelines. Data was pooled using random-effects model. A meta-analysis of continuous outcome and proportions was performed using the meta routine in R v3.2.1. Ten studies were included. There was a statistically significant difference in IOP reduction favouring Standalone XEN45 at post-operative day 1, week 1, months 1, 3 and 6. There was a statistically significant difference in decrease in IOP-lowering medications favouring Standalone XEN45 at post-operative week 1 and month 1. Standalone XEN45 has superior IOP-lowering outcomes compared to XEN45-Phaco in the early post-operative period, up to 6months after surgery.

Primary Needling of the Ab Interno Gelatin Microstent Reduces Postoperative Needling and Follow-up Requirements

To evaluate the effect of primary needling at the time of ab interno gelatin microstent insertion on postoperative needling rates. Retrospective, interventional cohort study. Eighty-six eyes of 74 patients with no prior incisional surgery. Consecutive eyes with open-angle glaucoma refractory to medical treatment that underwent ab interno gelatin microstent insertion (XEN; Allergan Inc.) with or without primary needling. Primary outcome measure was the proportion of eyes requiring postoperative needling. Secondary outcome measures included the mean reduction in intraocular pressure (IOP), topical glaucoma medication use, complications, reoperations, and number of follow-up clinic visits over 12 months. Fifty-one eyes (42 patients, median age 74 years) underwent XEN surgery with primary needling at the time of surgery, and 35 eyes (32 patients, median age 73 years) underwent XEN surgery without routine primary needling. Eyes that received routine primary needling had an 84.8% lower rate of postoperative needling (3.9% vs. 25.7%, P= 0.003) and required fewer postoperative clinic visits (P= 0.043). Median IOP was 18.0 mmHg (interquartile range [IQR], 13.0-23.0) on 3.0 (IQR, 2.0-3.0) classes of topical medications at baseline. At 12 months, the median IOP was 11.0 mmHg (IQR, 9.0-14.0) in the primary needling group and 11 mmHg (IQR, 10.0-14.0) when primary needling was not routinely performed. Both groups demonstrated a high safety profile. In total, 5 eyes required further glaucoma surgery with insertion of a glaucoma drainage device. Primary needling at the time of XEN gel stent insertion is associated with a significant reduction in the need for postoperative needling and postoperative clinic visits. This modification provides a predictable postoperative course with a significant and sustained reduction in both IOP and glaucoma medication requirements with less intense postoperative management.

Safety and efficacy of bilateral simultaneous XEN implant surgery: a pilot study.

To evaluate the efficacy and safety of the bilateral simultaneous XEN (BISIXEN) surgery in open-angle glaucoma patients. Retrospective analysis of a prospective data base conducted on uncontrolled glaucoma patients who underwent BISIXEN surgery. Primary endpoint measure was the incidence of sight-threatening complications. Secondary endpoints included intraocular pressure (IOP) reduction and in number of required antiglaucoma medications. Ten patients (20 eyes) were included in the analysis. Median (95% confidence interval) follow-up was 12.0 (7.0-12.0) months, with 14 eyes having a follow-up of 12months. No sight-threatening complications, such as endophthalmitis, retinal detachment, corneal decompensation, or intraocular hemorrhages were observed in any eye of study sample. Mean IOP decreased significantly from 25.2 (21.5-28.9) mm Hg at baseline to 15.1 (13.4-16.8) mm Hg at the last follow-up visit (p = 0.0001). Mean number of antiglaucoma medications was significantly reduced from 2.9 (2.5 to 3.3) drugs at baseline to 0.40 (0.00-0.70) at the end of the study (p < 0.0001). At the last study visit, 14 (70.0%) eyes had an IOP ≥ 6 and ≤ 18mm Hg without treatment. Two eyes needed surgical revision and three ones needed a new glaucoma surgery: two underwent Ahmed valves (one eye with aniridia and the other previously operated on) and one underwent non-penetrating deep sclerectomy. Bilateral simultaneous XEN implantation may be a feasible strategy in those patients with high anesthetic risk.

Needling after XEN gel implant: What's the efficacy? A 1-year analysis.

To analyse the long-term efficacy and safety of bleb needling in glaucoma patients previously submitted to XEN implantation. Retrospective, observational study. Charts from patients who underwent XEN gel implant surgery between October 2015 and December 2017 were reviewed. Needling protocol involves use of Mitomycin C 0.2 mg/mL in an operating room. Primary outcome was defined as intraocular pressure (IOP) lowering efficacy at 12 months post-operative. Complete success was defined as a decrease in IOP > 20% and overall value <18 mmHg. Secondary outcomes included safety parameters (both intra and post-operative). Exploratory analysis of predictive factors for success were performed. Statistical analysis was performed using SPSS version 24. About 94 charts were reviewed, with 18 patients (19%) having undergone needle revision. This salvage procedure was performed after 3.3 ± 3.4 months, achieving a mean IOP reduction of 8.3 ± 8.4 mmHg at 12 months after the procedure (pre-needling: 24.0 ± 5.2 mmHg vs 12th month: 13.5 ± 5.9 mmHg, p < 0.0001). Accordingly, success was achieved in 72% (complete success in 61% of cases). Among predictive factors, there was a higher tendency for success in patients on two types of medications or fewer pre-operatively, cases of standalone XEN surgery and patients with a higher IOP difference pre-needling - day 1. No vision-threatening complications were recorded. XEN salvage procedure with mitomycin C is a valid option in early bleb failure. This single intervention had a long-lasting effect on bleb survival, with almost two-thirds achieving long term significant drop-free IOP reduction.

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

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. 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. 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. 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.

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

To evaluate the 2-year treatment outcomes of the XEN gel stent (Allergan, Inc, Irvine, CA) in glaucoma patients. Prospective, single-center interventional study. One hundred forty-nine eyes of 113 patients with open-angle glaucoma. 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. 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. 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. 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.

Real-World Retrospective Consecutive Study of Ab Interno XEN 45 Gel Stent Implant with Mitomycin C in Black and Afro-Latino Patients with Glaucoma: 40% Required Secondary Glaucoma Surgery at 1 Year.

PURPOSE:The aim of this study was to determine the postoperative course after the ab interno XEN45 Gel Stent implantation in Black and Afro-Latino, patients with glaucoma.METHODS:This was a single-center, retrospective study. All patients with glaucoma who underwent ab interno XEN implantation were included in the study. All of the patients were Black and Afro-Latino making up the demographics of the local community. Investigated parameters were intraocular pressure (IOP), the number of medications, visual acuity, IOP-follow-up, intraoperative and postoperative complications, and additionally performed surgeries.RESULTS:Of 20 eyes that had undergone the procedure with 1-year follow-up, eight failed before 12 months requiring additional glaucoma surgery. Of the 12 that were successful at 1 year, 9 (75%) eyes underwent XEN + cataract surgery and 3 (25%) had XEN surgery alone. Of the eyes that completed 12-month follow-up, the mean medicated IOP was 15.3 ± 6.2 mmHg at baseline, and 12.9 ± 4.5 mmHg at 12 months, a 16% IOP reduction. Mean medications dropped from 3.58 ± 0.7 preoperatively to 1.75 ± 1.5 at 12 months.CONCLUSIONS:The ab interno XEN gel implant as a standalone procedure or combined with cataract surgery demonstrated a safe and sustained IOP reduction for only 60% of patients after 12 months. In Black and Afro-Latino patients receiving the ab interno XEN implant, 40% of patients needed additional surgery within 12 months.

Is a Day 1 postoperative review following ab interno Xen gel stent surgery for glaucoma needed?

PurposeTo assess whether a first day review is needed following Xen surgery in glaucoma patients.Patients and methodsWe performed a retrospective case note review of all Xen surgeries performed across four centers between August 2015 and May 2017. Intraocular pressure (IOP), number of medications, complications, and all further procedures were recorded.ResultsTwo hundred and fifty-nine cases from 226 patients were analyzed, 78 of 259 cases (30.1%) had numerical hypotony (<6 mmHg) on Day 1, but 60 had resolved by Week 1. Zero cases of hypotony required intervention at Day 1. Two of 259 cases (0.8%) had transient IOP of ≥20 mmHg due to air bubble/iris blockage on Day 1 with one case (0.4%) requiring iris manipulation at the slit-lamp. One case (0.4%) required IOP lowering medications at Day 1. All other complications and interventions in our series occurred at 1 week or beyond. Day 1 IOP was not shown to be a reliable indicator for outcomes at Week 1 (r2=0.2155), Month 1 (r2=0.0574), or Month 12 (r2=0.1580).ConclusionThe presence of significant complications requiring intervention at Day 1 was 0%. Only one case (0.4%) required topical IOP lowering medication and one case (0.4%) needed stent manipulation at Day 1. Day 1 IOP is not a reliable indicator of long-term outcomes in Xen surgeries. Removing Day 1 follow-up would have been safe in our series and it may be more effective to perform the first postoperative review of Xen surgery at Week 1.

Prospective Evaluation of XEN Gel Implant in Eyes With Pseudoexfoliative Glaucoma

The main purpose of this study was to compare the safety and efficacy of XEN gel implant surgery in patients with pseudoexfoliative glaucoma (PEXG) and primary open-angle glaucoma (POAG). This was a prospective, interventional study in a tertiary glaucoma center. Fifty-seven eyes (43 patients) with POAG and 53 eyes (42 patients) with PEXG with uncontrolled intraocular pressure (IOP) despite medical treatment underwent combined XEN+cataract surgery or standalone XEN surgery. Mean IOP, mean number of medications at 1-year follow-up, needling rates, and incidence of adverse effects (AEs) were analyzed. Complete success, defined as an IOP <16 mm Hg without medications at 1 year, was also analyzed. Combined XEN+cataract surgery was performed in 72% of POAG and 75% of PEXG eyes (P=0.674), the remainder underwent standalone XEN surgery. Patient characteristics were similar between the 2 groups except for higher age for the PEXG patients (78.5±8.5 vs. 71.3± 8.7 y; P<0.001). Mean medicated IOP was 19.8±5.8 (POAG) and 19.7±8.2 (PEXG) at baseline (P=0.98) and 13.9±4.6 (-29.8%) and 13.6±4.3 mm Hg (-31%) at 1 year (P=0.87), respectively (P<0.01). Mean medications dropped from 1.9±1.6 (POAG) and 2.0±1.3 (PEXG) preoperatively to 0.4±0.8 and 0.5±0.8, respectively at 1 year (P<0.001). A total of 42% (POAG) and 63% (PEXG) eyes achieved complete success (P=0.06) at 1 year. Needling was performed in 36.8% (POAG) versus 37.7% (PEXG) (P=0.923). The XEN gel implant as a standalone or combined procedure demonstrated similar efficacy and safety results in PEXG and POAG eyes.

Efficacy and Safety of the Ab-interno Xen Gel Stent After Failed Trabeculectomy.

To assess the efficacy and safety of the Xen gel stent in reducing intraocular pressure (IOP) in eyes with prior failed trabeculectomy and to determine the frequency of complications and further intervention. Retrospective case note review of all patients with prior trabeculectomy undergoing Xen surgery across 5 centers from August 2015 to May 2017. In total, 17 surgeries were reviewed. IOP reduced from 21.5 (±2.4) mm Hg preoperatively to 13.6 (±3.4) mm Hg at month 12 (P<0.05). Medication usage reduced from 2.8 (±0.6) preoperatively to 1.0 (±1.3) at month 12 (P<0.05). Adverse events included: numerical hypotony (IOP<6 mm Hg) in 4 cases (23.5%) that all resolved spontaneously, IOP spike of ≥30 mm Hg in 2 (11.8%) cases and transient occlusion of the implant by iris in 1 (5.9%) case. Secondary filtration surgery (Baerveldt tube implantation) was required in 2 (11.8%) cases. Postoperative bleb intervention was required in 9 cases (52.9%), usually in the first month after surgery. Xen reduces IOP and number of medications in eyes with failed trabeculectomy. Detailed preoperative conjunctival assessment and targeted stent placement is required. Prospective data and follow-up beyond 12 months are required but Xen seems a viable, effective, and safe option after failed trabeculectomy.

Sub‐conjunctival drainage

SummaryMinimally invasive glaucoma surgery (MIGS) has a favourable safety profile compared to traditional filtering glaucoma surgery. The term MIGS was originally coined to utilize the eyes natural outflow pathways. Newer subconjunctival surgeries have shown much promise in the published literature thus far whilst still maintaining excellent safety, and therefore the remit of MIGS has expanded. Xen surgery is an ab‐interno implant that has internal lumen of 45 microns and total length of 6mm. It is inserted via both gonioscopic and external visualisation penetrating sclera 3mm from the limbus usually in the superior nasal quadrant. I will discuss strategies to try and achieve reproducible sub‐conjunctival placement of the Xen implant to achieve and maintain target IOP and reduce the risk of encapsulation and further post‐op manipulations. Innfocus micro‐shunt is an ab‐externo implant. Its internal lumen is 70microns and total length is 8mm. Its placement involves a periotomy and dissection of tenon's to create a potential space for drainage. It is inserted 3mm from the limbus and can be placed in any quadrant of the eye. Pearls on intra‐operative and post‐operative management will be discussed in the symposium.

Prospective study of filtering blebs after XEN45 surgery

Abstract Objective To qualitatively analyze the evolution of filtering blebs after XEN surgery, by using anterior segment optical coherence tomography (AS-OCT). Methods A prospective study was performed on filtering blebs of 30 eyes with cataracts and glaucoma, surgically operated on using phacoemulsification and XEN45 implantation (PHACO-XEN). AS-OCT was used to analyze bleb morphology and reflectivity at 3, 6, and 12 months after surgery. Functionality was studied considering an intraocular pressure (IOP) ≤ 18 mm Hg without antihypertensive medication. Results The IOP enabled the blebs to be classified into non-functional: flat (6.67%) and encapsulated (3.33%); and functional (90%), which were then divide by their morphology into cystic (5/27), diffuse (2/27), and layered (20/27). Cystic types had a mean IOP of 12.8, 12.6, and 14.0 mm Hg at 3, 6 and 12 months, respectively. In the diffuse type, the mean IOP was 13.0, 11.5 and 13.0 mm Hg at 3, 6 and 12 months, respectively. In the layers pattern the mean IOP was 14.45, 14.55 and 14.8 mm Hg at 3, 6 and 12 months respectively. The percentage of blebs with high reflectivity was 48.15%, 62.96%, and 77.78%, at 3, 6 and 12 months, with a mean IOP of 14.23, 14.59, and 15.14 mm Hg in each time period, respectively. Conclusion AS-OCT could be a good predictor of bleb functionality in PHACO-XEN surgery. Those with a cystic pattern or low reflectivity seem to have better post-operative success. Nevertheless, more long-term studies are required.

Estudio prospectivo de las ampollas de filtración poscirugía de implante XEN45

ObjectiveTo qualitatively analyse the evolution of filtering blebs after XEN surgery, by using anterior segment optical coherence tomography (AS-OCT). MethodsA prospective study was performed on filtering blebs of 30 eyes with cataracts and glaucoma, surgically operated on using phacoemulsification and XEN45 implantation (PHACO-XEN). AS-OCT was used to analyse bleb morphology and reflectivity at 3, 6, and 12 months after surgery. Functionality was studied considering an intraocular pressure (IOP)≤18mmHg without antihypertensive medication. ResultsThe IOP enabled the blebs to be classified into non-functional: flat (6.67%) and encapsulated (3.33%); and functional (90%), which were then divide by their morphology into cystic (5/27), diffuse (2/27), and layered (20/27). Cystic types had a mean IOP of 12.8, 12.6, and 14.0mmHg at 3, 6 and 12 months, respectively. In the diffuse type, the mean IOP was 13.0, 11.5 and 13.0mmHg at 3, 6 and 12 months, respectively. In the layers pattern the mean IOP was 14.45, 14.55 and 14.8mmHg at 3, 6 and 12 months respectively. The percentage of blebs with high reflectivity was 48.15%, 62.96%, and 77.78%, at 3, 6 and 12 months, with a mean IOP of 14.23, 14.59, and 15.14mmHg in each time period, respectively. ConclusionAS-OCT could be a good predictor of bleb functionality in PHACO-XEN surgery. Those with a cystic pattern or low reflectivity seem to have better post-operative success. Nevertheless, more long-term studies are required.