Microinvasive Glaucoma Surgery Research Articles

Glaucoma surgery preferences when the surgeon adopts the role of the patient.

To survey the members of the American Glaucoma Society (AGS) to determine which glaucoma procedures they would prefer to have performed on themselves. We distributed an anonymous, electronic survey via the AGS listserv. The participants were asked to adopt the role of a patient with primary open angle glaucoma with progressive visual field loss in need of glaucoma surgery. Three preoperative intraocular pressure (IOP) levels were provided (>26 mmHg, 21-26 mmHg, and <21 mmHg), and the participants were asked to choose a glaucoma procedure they would prefer performed on themselves under each preoperative IOP levels from a list of fifteen procedures. Out of 289 responses (representing 27.4% of active and provisional AGS members), the most preferred procedures were ab interno trabeculotomy (20.3%), Xen gel stent (18.6%), iStent with two devices (14.3%) and traditional trabeculectomy augmented with mitomycin C (14.1%). 17.6% and 6.9% of participants preferred a trabeculectomy performed or a glaucoma drainage device (GDD) implanted on themselves, which is a lower than what would be offered to a hypothetical patient. Significant proportions of participants prefer non-bleb forming or conjunctiva-sparing procedures, even with low preoperative IOP levels. Older participants were more likely to prefer traditional trabeculectomy and having a single procedure across all levels of preoperative IOP. The majority of AGS participants in the survey would prefer micro-invasive glaucoma surgery over traditional trabeculectomy or a GDD performed on themselves as a primary glaucoma procedure, and most would prefer non-bleb forming and conjunctiva-sparing procedures.

A Prospective Randomized Trial Comparing Hydrus and iStent Microinvasive Glaucoma Surgery Implants for Standalone Treatment of Open-Angle Glaucoma: The COMPARE Study

To compare the efficacy of different microinvasive glaucoma surgery (MIGS) devices for reducing intraocular pressure (IOP) and medications in open-angle glaucoma (OAG). Prospective, multicenter, randomized clinical trial. One hundred fifty-two eyes from 152 patients aged 45 to 84 years with OAG, Shaffer angle grade III-IV, best-corrected visual acuity (BCVA) 20/30 or better, and IOP 23 to 39 mmHg after washout of all hypotensive medications. Eyes with secondary glaucoma other than pseudoexfoliative or pigmentary glaucoma, angle closure, previous incisional glaucoma surgery, or any significant ocular pathology other than glaucoma were excluded. Study eyes were randomized 1:1 to standalone MIGS consisting of either 1 Hydrus Microstent (Ivantis, Inc, Irvine, CA) or 2 iStent Trabecular Micro Bypass devices (Glaukos Inc, San Clemente, CA). Follow-up was performed 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. Within-group and between-group differences in IOP and medications at 12 months and complete surgical success defined as freedom from repeat glaucoma surgery, IOP 18 mmHg or less, and no glaucoma medications. Safety measures included the frequency of surgical complications, changes in visual acuity, slit-lamp findings, and adverse events. Study groups were well matched for baseline demographics, glaucoma status, medication use, and baseline IOP. Twelve-month follow-up was completed in 148 of 152 randomized subjects (97.3%). At 12 months, the Hydrus had a greater rate of complete surgical success (P < 0.001) and reduced medication use (difference= -0.6 medications, P= 0.004). More Hydrus subjects were medication free at 12 months (difference= 22.6% P= 0.0057). Secondary glaucoma surgery was performed in 2 eyes in the 2-iStent group (3.9%) and in none of the Hydrus eyes. Two eyes in the Hydrus group and 1 in the 2-iStent group had BCVA loss of ≥2 lines. Standalone MIGS in OAG with the Hydrus resulted in a higher surgical success rate andfewermedications compared with the 2-iStent procedure. The 2 MIGS devices have similar safety profiles.

Anterior Chamber Angle, Volume, and Depth in a Normative Cohort—A Retrospective Cross-Sectional Study

ABSTRACTPurpose: The purpose of the study was to determine the distribution of the anterior chamber angle (ACA) within a population-based study sample in Germany and to find correlations between age, sphere, and biometric parameters of the anterior chamber.Patients and Methods: A total of 500 eyes, approximately 100 eyes per decade starting with patient age of 20 years, of 463 patients with an average age of 45.2 ± 14.1 (±values subsequent represent standard deviation) years without any known history of ocular diseases, surgery, or optic nerve head excavation or hypoplasia were included.ACAs, volume, and depth were correlated to age and sphere. Scheimpflug images (Pentacam, Oculus) with automatically measured ACAs were compared to manually measured angles (Bland Altman analysis) in this healthy population.Results: The mean manually measured ACA was 26.5° ± 3.9°; the highest average angle was found in the temporal position with 28.1° ± 4.9°, while the lowest average angle was found in nasal superior position with 25.7° ± 4.7°.Statistical analysis showed an average difference of +11.4° nasal and +12.1° temporal between the automatic measurements and the manually measured angles (P < 0.01). The analysis also revealed an independent inverted correlation between age (correlation coefficient between −0.28 and −0.38) and sphere (correlation coefficient between −0.44 and −0.51) of the participants and the anterior chamber volume, angle, and anterior chamber depth (P < 0.01 for all correlations).Conclusion: The ACA width manually measured is considerably less compared to automated imaging and formerly reported values. There is a significant difference in the ACA dependent on the position of measurement (superior, nasal, inferior, and temporal) with the average angle being inversely correlated to age and sphere.Abbreviations: AC: anterior chamber ACA: anterior chamber angle ACV: anterior chamber volume ACD: anterior chamber depth AAC: acute angle closure OAG: open-angle glaucoma OCT: optical coherence tomography ACG: angle-closure glaucoma MIGS: microinvasive glaucoma surgery PACS: primary angle-closure suspects

Episcleral Venous Fluid Wave in the Living Human Eye Adjacent to Microinvasive Glaucoma Surgery (MIGS) Supports Laboratory Research: Outflow is Limited Circumferentially, Conserved Distally, and Favored Inferonasally.

The purpose of this study was to describe downstream patterns of outflow with the episcleral venous fluid wave (EVFW) in the living human eye adjacent to microinvasive glaucoma surgery (MIGS) and determine if the EVFW supports existing ex-vivo laboratory outflow research. Retrospective, noncomparative case series. A total of 10 eyes of 10 patients who underwent phaco-Trabectome and 10 eyes of 10 patients who underwent phaco-iStent consecutively at Glaucoma Associates of Texas for cataract and uncontrolled glaucoma who demonstrated an episcleral wave. The EVFW was visualized and recorded during irrigation and aspiration. To describe the hydrodynamic properties of the fluid wave, its degrees, extent, and characteristics were measured with a protractor in Photoshop. The incised Trabectome arc produced adjacent episcleral blanching of 134±11 degrees (range, 112 to 150 degrees) with an additional 54 degrees of marginal recruitment (41 degrees inferonasal plus 13 degrees superonasal) adjacent to the ends of the Trabectome incision. The mean episcleral blanch for the iStent was 51±19 degrees (range, 19 to 90 degrees), comprised of 29 degrees inferonasal plus 22 degrees superonasal. Downstream episcleral flow in the living human eye adjacent to the iStent is variable and mainly confined to 2 clock hours indicating a lack of significant circumferential flow in glaucomatous eyes. Flow distal to the Trabectome site encompasses the Trabectome incisional arc with an additional 2 clock hours of lateral fluid wave favoring the inferonasal over superonasal quadrant 3 to 1. These in-vivo findings made visible with MIGS, corroborate recent in-vivo and long-standing ex-vivo laboratory research that outflow is largely segmented, favored inferonasally and conserved distally.

Seven- and eight-year trends in resident and fellow glaucoma surgical experience.

PurposeThis study evaluated US resident and fellow glaucoma surgical experience over a 7- and 8-year period, respectively.MethodsUS ophthalmology resident glaucoma case logs from 2009 to 2016 and glaucoma fellow case logs from 2008 to 2016 were reviewed. The number of total, average, median, and minimum cases, along with percentile data for filtering surgery, shunting surgery, and novel procedures were analyzed for year-to-year trends.ResultsAmong residents training from 2009 to 2016, there was a decline in the average number of primary filtering surgeries by 20%, from 6.0±5.0 to 4.8±4.0 cases, with a concurrent increase in average primary glaucoma drainage implant (GDI) surgeries by 40%, from 4.5±4.0 to 6.3±5.0 cases, which represented an increase of 6.5% per year, P<0.001. Glaucoma fellow data from 2008 to 2015 demonstrated a decline in average primary trabeculectomy surgeries by 3.7%, from 30.1 to 29.0 cases, but then increased to 32.1 cases in 2015–2016. There was an increase in average GDI surgeries by 57.9%, from 30.2 to 47.7 cases for fellows over this 8-year period, which represented a 5.9% increase per year, P<0.001. There was no microinvasive glaucoma surgery (MIGS) or other novel procedures reported in the Accreditation Council for Graduate Medical Education (ACGME) resident case logs. From 2008 to 2016, Association of University Professors of Ophthalmology (AUPO) glaucoma fellow case logs demonstrated an increase in endocyclophotocoagulation (ECP) from 2.3 to 5.4 cases, a 15.5% increase per year, P<0.001.ConclusionsOver a 7–8-year period, trainee surgical experience with GDI surgery has steadily increased, whereas surgical experience with trabeculectomy has been fluctuating and may be on a downward trend. Educators should be aware of shifts in trainee surgical experience in order to maintain appropriate training experience.

Significant IOP reduction after combined phacoemulsification and micro-invasive glaucoma surgery (MIGS)

Significant IOP reduction after combined phacoemulsification and micro-invasive glaucoma surgery (MIGS)

360° ab-interno trabeculotomy in refractory primary open-angle glaucoma.

PurposeThe purpose of this study was to evaluate the safety and efficacy of microinvasive glaucoma surgery (MIGS) with 360° ab-interno trabeculotomy using the TRAB360 device as a stand-alone procedure in patients with refractory primary open-angle glaucoma (POAG) and preoperative IOP ≥18 mmHg.SettingThis study evaluated patients treated in a tertiary-referral clinical practice setting.DesignThis study is a retrospective analysis of 81 eyes.MethodsPatients with refractory open-angle glaucoma underwent stand-alone 360° ab-interno trabeculotomy using the TRAB360 device. Effectiveness was determined by reduction in medicated IOP and the use of medications from baseline. Safety was determined by the rate of adverse events and secondary surgical interventions. The time points assessed were baseline and postoperative day 1, week 1, and months 1, 3, 6, and 12. A subgroup analysis was performed on eyes with medicated preoperative IOP values of ≥25 mmHg.ResultsThe reductions in IOP from 1 day to 12 months postoperatively were statistically significant compared to baseline values. The mean reduction in IOP at 12 months was 7.3±6.7 mmHg from baseline. At 12 months, 59% eyes achieved ≥20% reduction in IOP and IOP <18 mmHg with the same or fewer numbers of IOP-lowering medications compared with those at baseline. The mean number of IOP-lowering medications was reduced from 1.7±1.3 at baseline to 1.1±1.0 at 12 months. At 12 months, 67% of eyes with preoperative IOP values of ≥25 mmHg achieved ≥20% reduction in IOP and IOP <18 mmHg with the same or fewer numbers of IOP-lowering medications compared with those at baseline. The most common adverse event for all eyes was mild, transient hyphema (57 eyes). During the first year after the procedure, 20 (25%) eyes were considered failures since they required reinterventions.ConclusionTrabeculotomy using the TRAB360 device resulted in significant IOP reductions up to 1 year with a favorable safety profile. The device is an effective stand-alone MIGS procedure for patients with refractory POAG.

Development of a drug-eluting microstent for micro-invasive glaucoma surgery

Abstract Glaucoma represents the leading cause of irreversible blindness worldwide. Therapeutic approaches are based on the lowering of intraocular pressure (IOP). Micro-invasive glaucoma surgery (MIGS) offers perspectives for implant based IOP-reduction with reduced complication rates compared to conventional surgical approaches. Nevertheless, available devices suffer from complications like hypotony and fibrotic encapsulation. The current work focuses on the development of a minimally invasive implantable drugeluting microstent for the drainage of aqueous humour into suprachoroidal or subconjunctival space. Technical feasibility of a micro-scale resorbable nonwoven for the prevention of hypotony and of a drug-eluting coating for the prevention of fibrosis is assessed. Microstent base bodies with a length of 10 mm and an inner/outer diameter of 0.20 mm / 0.35 mm were manufactured. For the prevention of hypotony, resorbable nonwovens with an adequate flow resistance of 1.543 mmHg/μl min-1 were manufactured in the inflow area of microstents. A drug-eluting coating in the outflow area of microstents was developed based on the model drug fluorescein diacetate. Micro-invasive ab interno implantation of a microstent prototype into suprachoroidal space of a porcine eye post mortem was successfully performed, using an injector device. Future studies will focus on the development of an antifibrotic drug-eluting coating and further in vitro, ex vivo and in vivo testing of the devices.

Systematic Literature Review of Clinical and Economic Outcomes of Micro-Invasive Glaucoma Surgery (MIGS) in Primary Open-Angle Glaucoma.

IntroductionPrimary open-angle glaucoma is estimated to affect 3% of the population aged 40–80 years. Trabeculectomy is considered the gold standard in surgical management of glaucoma; however, it is a technically complex procedure that may result in a range of adverse outcomes. Device-augmented, minimally invasive procedures (micro-invasive glaucoma surgeries, MIGS) have been developed aiming for safer and less invasive intraocular pressure (IOP) reduction compared with traditional surgery.MethodsThis paper presents results from a systematic literature review conducted in accordance with National Institute for Health and Care Excellence requirements for the Medical Technology Evaluation Programme via multiple databases from 2005 to 2016. For clinical outcomes, randomized clinical trials (RCTs) comparing MIGS with trabeculectomy or other therapies, observational studies, and other non-RCTs were included. Clinical outcomes reviewed were the change from baseline in mean IOP levels and change in topical glaucoma medication. Safety was assessed by reported harm and adverse events. For economic evidence, trials on cost-effectiveness, cost-utility, cost-benefit, cost-consequences, cost-minimization, cost of illness, and specific procedure costs were included. Risk of bias was assessed for clinical studies using the Cochrane Risk of Bias tool.ResultsA total of nine RCTs (seven iStents®, one Hydrus®, and one CyPass®), seven non-RCTs (three iStent®, three CyPass®, and one Hydrus®), and 23 economic studies were analyzed. While various forms of trabeculectomy can achieve postoperative IOP of between 11.0 and 13.0 mmHg, MIGS devices described in this review were typically associated with higher postoperative IOP levels. In addition, MIGS devices may result in increased hypotony rates or bleb needling in subconjunctival placed devices, requiring additional medical resources to manage. There is limited available evidence on the cost-effectiveness of MIGS and therefore it remains unclear whether the cost of using MIGS is outweighed by cost savings through decreased medication and need for further interventions.ConclusionLarger randomized trials and real-world observational studies are needed for MIGS devices to better assess clinical and economic effectiveness. Given the shortage of published data and increasing use of such procedures, living systematic reviews may help to provide ongoing and timely evidence-based direction for clinicians and decision makers. This review highlights the current unmet need for treatments that are easy to implement and reduce long-term IOP levels without increasing postoperative aftercare and cost.FundingSanten GmbH, Germany.Electronic supplementary materialThe online version of this article (10.1007/s40123-018-0131-0) contains supplementary material, which is available to authorized users.

Progress of microinvasive glaucoma surgery

Surgery is one of crucial treatments for glaucoma. The microinvasive glaucoma surgery (MIGS), with higher safety and less impact on the anatomical structure of eye, is gradually rising and mature. Compared with conventional glaucoma surgeries, MIGS is relatively simple, with less complications, and less impact for the quality of life.This kind of surgery can be conducted in 3 different space, such as Schlemm canal, the suprachoroidal space, and the subconjunctival .This article reviews briefly the current progress of microinvasive glaucoma surgery. Key words: Surgery, glaucoma, microinvasive; Pressure, intraocular, depressing; Progress

Trabecular micro-invasive glaucoma surgery : Procedures and clinical results

The management of glaucoma therapy to reduce intraocular pressure commonly consists of agradual approach with local monotherapy, combined therapy, laser surgery and finally filtration surgery. The local side effects of glaucoma medications and the lack of adherence and persistence to the medical therapy as well as the complication profile of the established glaucoma surgical techniques justify the introduction of new surgical procedures. Micro-invasive glaucoma surgery (MIGS) is apromising new surgical approach. Microstents can reduce the medication burden and prolong the need for filtration surgery. This review article presents the different trabecular implants (iStent, iStent inject, HydrusTM Microstent) in detail and discusses the effectiveness and safety of the procedures based on the currently available data.

Complications of micro-invasive glaucoma surgery.

Micro-invasive glaucoma surgery (MIGS) is gaining favor with both comprehensive ophthalmologists and glaucoma specialists due in part to its improved safety profile when compared to traditional incisional glaucoma surgery. Despite a micro-invasive approach and minimal induced tissue trauma, each MIGS procedure is associated with unique complications. The present article summarizes evidence from the 2016 to 2017 review period regarding the safety profiles of Schlemm's canal-based, suprachoroidal, and subconjunctival microstents. Ab-interno microstents are subject to intraoperative malpositioning, which can result in luminal obstruction and decreased efficacy. Acutely elevated intraocular pressure (IOP) has been observed with the iStent (Glaukos Corp., Laguna Hills, CA, USA; 2-4.3%), Hydrus Microstent (Ivantis Inc., Irvine, CA, USA; 6%), Cypass Microstent (Alcon, Fort Worth, TX, USA; 3-10.8%), and Xen Gel Stent (Allergan Plc, Dublin, Ireland; 21.5%). Meanwhile, most cases of hypotony (IOP < 6 mmHg) occurred within the first postoperative month, resolved with conservative treatment and without further surgical intervention, and were not associated with vision-threatening sequelae. Interest in MIGS continues to grow as these procedures allow surgeons to intervene earlier in the disease course for patients with milder stages of glaucoma. Complications associated with MIGS, albeit infrequent and mostly transient, do occur despite a less invasive approach than trabeculectomy and tube shunt surgery.

Erratum: Micro-invasive glaucoma surgery (MIGS): a review of surgical procedures using stents [Corrigendum

[This corrects the article on p. 1583 in vol. 11, PMID: 28919702.].

Navigating a new direction in micro-invasive glaucoma surgery: results from the COMPASS trial

Recent innovations and technological advances have ushered in a new era of surgical approaches to glaucoma management. Our options have expanded beyond traditional incisional glaucoma surgery (i.e., trabeculectomy and tube shunts) to include newer procedures that can be implemented earlier in patients with milder disease. Many of these recently introduced operations can be classified as micro-invasive glaucoma surgery (MIGS), for which five defining criteria have been proposed: an ab interno approach; minimal tissue trauma; at least modest efficacy; high safety; and rapid recovery (1). Candidates for currently available MIGS are generally those with early glaucoma whose disease does not require very low intraocular pressure (IOP) to retard progression and/or who may benefit from reduction in medical therapy.

Gel Stent Implantation—Recommendations for Preoperative Assessment, Surgical Technique, and Postoperative Management

The surgical management of glaucoma offers the potential to lower intraocular pressure (IOP) independent of patients’ compliance with their medication regimen. Procedures such as trabeculectomy and tube shunt placement often yield large magnitudes of IOP reduction, but may be associated with short- and long-term complications. Microinvasive glaucoma surgery (MIGS) offers an alternative surgical approach that is inherently less invasive; however, most devices that fit in this category are associated with a lesser degree of IOP-lowering efficacy compared with traditional glaucoma surgeries. A newer MIGS device, a gel stent that facilitates drainage to the subconjunctival space, appears to offer similar IOP reduction to trabeculectomy, but with much less tissue manipulation; better predictability; and less sight-threatening complications, thus making it a potentially safer and more predictable surgical option in appropriate patients. The following proposed protocol, based on evidence-based practices and augmented where necessary by the opinions of experienced surgeons, provides guidance for the pre-, intra-, and postoperative management of patients receiving a gel stent implant. The goal of this protocol is to provide a framework for better patient selection and preparation, surgical pearls, and how best to assess and manage patients in the postoperative period.

Update on Microinvasive Glaucoma Surgery.

Update on Microinvasive Glaucoma Surgery.

XEN-45 Gel Stent implant in glaucoma treatment

The XEN-45 drainage implant is a hypotensive device made of hydrophilic gelatin and stabilized by glutaraldehyde. The implant is designed for modern Microinvasive Glaucoma Surgery (MIGS). Being installed ab interno, the stent drains aqueous fluid from the anterior chamber into the subconjunctival space. According to indications, XEN-45 can be used in treatment of primary open angle glaucoma, pseudoexfoliation or pigment glaucoma with uncompensated intraocular pressure amid maximum tolerated hypotensive therapy, and refractory glaucoma including cases with history of unsuccessful surgery. The implant can also be effectively used in combination with phacoemulsification. The article describes the structure and implantation process of the XEN drainage and reviews existing clinical trials on its effectiveness. The article also presents results on hypotensive efficacy of the implant, as well as characteristics and complications of postoperative management.

Surgeon perspectives on learning ab-interno gelatin microstent implantation

ObjectiveTo evaluate and compare the surgeon’s learning experience with an ab-interno gelatin microstent (XEN-45, Allergan) to other glaucoma surgeries. DesignCross-sectional survey study. MethodsAll surgeons in Canada who used the gelatin microstent were identified and given an anonymous online survey (FluidSurveys, Survey Monkey) designed to evaluate key factors associated with the device, including prior surgical experience, patient selection criteria, analysis of each surgical step, and postoperative care. The survey was validated using input from 3 experienced glaucoma surgeons. ResultsSurgeons were in early to mid-career (11.8 ± 7.2 operating years) and experienced with filtration surgery (94.1% very comfortable). Surgeons would more commonly operate on patients who had moderate to advanced disease (88.2% and 76.5% of surgeons felt appropriate to operate, respectively); had a diagnosis of primary open angle glaucoma or pseudoexfoliative glaucoma (70.6%); were on 2, 3, or 4 glaucoma medications (70.6%, 75.5%, 70.6%, respectively); and had previously undergone microinvasive glaucoma surgery (83.3%). Creation of the scleral tunnel into the subconjunctival space was rated the most difficult step of the surgery. Most surgeons (52.9%) required 6–10 cases to be comfortable with the procedure and felt it was easier to gain proficiency with ab-interno microstent implantation than traditional filtration surgery (94.1% agree or strongly agree). ConclusionThe group of glaucoma surgeons surveyed felt it was easier to gain proficiency with gelatin microstent implantation than with traditional filtration surgery.

Micro-invasive glaucoma surgery (MIGS): a review of surgical procedures using stents.

Over the last decade several novel surgical treatment options and devices for glaucoma have been developed. All these developments aim to cause as little trauma as possible to the eye, to safely, effectively, and sustainably reduce intraocular pressure (IOP), to produce reproducible results, and to be easy to adopt. The term “micro-invasive glaucoma surgery (MIGS)” was used for summarizing all these procedures. Currently MIGS is gaining more and more interest and popularity. The possible reduction of the number of glaucoma medications, the ab interno approach without damaging the conjunctival tissue, and the probably safer procedures compared to incisional surgical methods may explain the increased interest in MIGS. The use of glaucoma drainage implants for lowering IOP in difficult-to-treat patients has been established for a long time, however, a variety of new glaucoma micro-stents are being manufactured by using various materials and are available to increase aqueous outflow via different pathways. This review summarizes published results of randomized clinical studies and extensive case report series on these devices, including Schlemm’s canal stents (iStent®, iStent® inject, Hydrus), suprachoroidal stents (CyPass®, iStent® Supra), and subconjunctival stents (XEN). The article summarizes the findings of published material on efficacy and safety for each of these approaches.

Role of glaucoma drainage device implantation in the treatment of refractory glaucoma

Refractory glaucoma is one of the main blinding diseases in ophthalmology.Glaucoma drainage device implantation has become one of the main methods of refractory glaucoma.It has been widely used in clinic because of its advantages of safety, effectiveness and less complications.After a large number of clinical applications and innovative development of minimally invasive glaucoma surgery, glaucoma drainage device implantation shows its good treatment prospects.In this paper, the structural features of glaucoma external drainage device (Molteno, Schocket, Baerveldt, Human aqueous drainage, Krupin, Ahmed, Joseph, Whites, Optimed drainage device) and micro-in vasive glaucoma surgery (MIGS) (Ex-PRESS drainage device, Xen Gel Stent, CyPass Micro-Stent, Ab interno trabeculectomy trabectome, Hydrus Schlemm canal scaffold, iStent trabecular micro-bypass stent, SOLX Gold Shunt) were summarized.The drainage device implantations for glaucoma in the role of the refractory glaucoma were reviewed. Key words: Glaucoma drainage device; Refractory glaucoma; Ex-PRESS glaucoma drainage device; Micro-invasive glaucoma surgery