Effectiveness and cost-effectiveness of MicroShunt implantation versus standard trabeculectomy for open-angle glaucoma (a SIGHT study): study protocol of a multicentre randomised controlled trial.

BACKGROUND: Trabeculectomy is the "gold standard" initial surgical procedure for open-angle glaucoma worldwide. During the last decade, the introduction of less invasive procedures, including new bleb-forming surgery such as the MicroShunt, has altered the approach of glaucoma management. At present, there is insufficient evidence comparing the effectiveness between these procedures nor versus trabeculectomy. Furthermore, there is no data available on patient impact and cost-effectiveness. This study aims to address this gap in evidence and establish whether MicroShunt implantation is non-inferior compared to trabeculectomy with regard to effectiveness and whether it is cost-effective. METHODS: A multicentre, non-inferiority, randomised controlled trial (RCT) studying open-angle glaucoma with an indication for surgery will be conducted. Patients with previous ocular surgery except for phacoemulsification are excluded, as are patients with ocular comorbidity compromising the visual field or requiring a combined procedure. After informed consent is obtained, patients will be randomly allocated to the intervention, a PRESERFLO™ MicroShunt implantation, or the control group, trabeculectomy, using block randomisation (blocks of 2, 4 or 6 patients). In total, 124 patients will be randomised in a 1:1 ratio, stratified by centre. The primary endpoint will be intraocular pressure (IOP) one year after surgery. Secondary outcomes include IOP-lowering medication use, treatment failure, visual acuity, visual field progression, additional interventions, adverse events, patient-reported outcome measures (PROMs), and cost-effectiveness. Study outcomes will be measured up to 12 months postoperatively. DISCUSSION: This study protocol describes the design of a multicentre non-inferiority randomised controlled trial. To this date, cost-effectiveness studies evaluating the MicroShunt have not been undertaken. This multicentre RCT will provide more insight into whether MicroShunt implantation is non-inferior compared to standard trabeculectomy regarding postoperative IOP and whether MicroShunt implantation is cost-effective. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier: NCT03931564 , Registered 30 April 2019.

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

PURPOSE: To evaluate the long-term efficacy and safety of two minimally invasive glaucoma surgery implants with a subconjunctival drainage approach: the XEN45 Gel Stent® (Xen) implant and the PRESERFLO™ MicroShunt (MicroShunt). METHODS: Retrospective comparative case series of primary open-angle glaucoma (POAG) patients with at least 6 months of follow-up after a MicroShunt or Xen implantation augmented with mitomycin C. RESULTS: Forty-one eyes of 31 patients underwent Xen implantation, and 41 eyes of 33 patients, MicroShunt implantation. Baseline characteristics were similar, except for more combined surgeries with phacoemulsification in the Xen group (37% vs. 2%). Mean baseline IOP ± standard deviation dropped from 19.2 ± 4.4 to 13.8 ± 3.8 mmHg (n = 26) in the Xen group and from 20.1 ± 5.0 to 12.1 ± 3.5 (n = 14) in the MicroShunt group at 24 months of follow-up (p = 0.19, t-test). The number of IOP-lowering medications dropped from 2.5 ± 1.4 to 0.9 ± 1.2 in the Xen group and from 2.3 ± 1.5 to 0.7 ± 1.1 in the MicroShunt group. The probability of qualified success was 73% and 79% at 24 months of follow-up for the Xen and MicroShunt groups, respectively. Postoperative complications were usually mild and self-limiting. The number of bleb needling and secondary glaucoma surgery procedures was similar in both groups; however, in the Xen group more additional MicroPulse® transscleral cyclophotocoagulation procedures were performed. CONCLUSION: Xen Gel Stent and PreserFlo MicroShunt implantations achieved comparable results in POAG eyes in terms of IOP-lowering and surgical success, with a similar high safety profile.

Micropulse Trans-scleral Cyclophotocoagulation in Patients With Glaucoma: 1- and 2-Year Treatment Outcomes.

PRéCIS:: Micropulse trans-scleral cyclophotocoagulation (TSCPC) is an effective and safe IOP-lowering treatment for patients with primary or secondary glaucoma. PURPOSE: To investigate the 1-year and 2-year effect on intraocular pressure (IOP) and safety profile of micropulse TSCPC in patients with glaucoma. METHODS: Patients with glaucoma underwent a standardized micropulse TSCPC (MicroPulse P3 probe, Iridex cyclo G6 laser system, Mountain View, CA) at the University Eye Clinic Maastricht from November 2016 to May 2018. Patients with at least 12 months of follow-up were included. RESULTS: A total of 141 eyes of 136 patients were included. The mean age was 67.2±14.5 years, and 56.6% of patients were male individuals. The glaucoma subtypes treated were primary glaucoma (n=99) and secondary glaucoma (n=42). Prior glaucoma surgery was performed in 59 of 141 eyes (41.8%). The mean preoperative IOP was 23.5±9.4 mm Hg. The mean postoperative IOP dropped to 16.8±8.4, 17.0±7.8, and 16.8±9.2 mm Hg, after 12, 18, and 24 months, respectively. The mean number of IOP-lowering medications used preoperatively was 3.3±1.4. The mean number of medications used at 12, 18, and 24 months was respectively 2.6±1.5, 2.5±1.4, and 2.2±1.5. Postoperative complications included cystic macular edema (n=2), hypotony maculopathy (n=1), fibrinous/uveitic reaction (n=1), and rejection of corneal graft (n=1), all reversible after treatment. One patient developed persisting hypotony in the late postoperative period. CONCLUSIONS: Micropulse TSCPC is a safe and effective treatment for lowering both IOP and the number of IOP-lowering medications. Micropulse TSCPC can also be considered as a good alternative treatment option for patients after failed incisional glaucoma surgery or patients who are at high risk for incisional surgery.