SIGHT Study: Cost-effectiveness of InnFocus Microshunt Implantation vs. Trabeculectomy.

The standard surgical treatment for glaucoma is trabeculectomy. The PRESERFLO™ (formerly InnFocus) Microshunt (IMS) is a new, minimally invasive drainage device which has been suggested to result in similar IOP lowering, but with faster visual recovery and less complications and postoperative interventions. The objective of this study is to aid in deciding on the use of the IMS in glaucoma surgery by assessing its efficacy and cost-effectiveness in patients with primary open angle glaucoma (POAG) compared to the standard trabeculectomy (TE).

During the last decade, minimally invasive glaucoma surgery (MIGS) procedures have been introduced to the market. MIGS procedures or devices, often small stents or tubes that can be placed into the eye, are potentially safer than standard trabeculectomy (TE). The surgery is faster and easier to perform. Patient recovery is faster with fewer postoperative visits, suggesting less impact on vision and quality of life. However, MIGS devices are more expensive compared to standard surgery and it is unclear if the higher costs can be compensated with their better safety profile and faster patient recovery (reduced productivity losses).

To establish guidelines for the use of MIGS, the Netherlands Glaucoma Group has recognized the need for a formal investigation of their cost-effectiveness as compared to TE, prior to their implementation on a large scale for regular care. Therefore, a societal cost-effectiveness analysis of MIGS procedures will be undertaken to further elucidate their position in the glaucoma treatment algorithm in the Netherlands.

The objective of this study is to aid in deciding on the use of the IMS in glaucoma surgery by assessing its efficacy and cost-effectiveness in patients with primary open angle glaucoma compared to trabeculectomy.

Eligibility Criteria:
Inclusion Criteria:

* Adult Caucasian patients aged between 18 and 80 years old with uncontrolled primary open angle glaucoma on (maximum tolerated) medical therapy and/or progression of visual field loss, an IOP ≥18 and ≤40 mmHg, and an indication for primary glaucoma surgery (trabeculectomy) are suitable for inclusion.

Exclusion Criteria:

1. Patient unwilling or unable to give informed consent, unwilling to accept randomization or inability to complete follow-up (e.g. hospital visits) or comply with study procedures
2. Secondary glaucoma (e.g. pigment dispersion syndrome, pseudo exfoliation syn-drome, iris neovascularization, rubeosis iridis, trauma, epithelial or fibrous down growth, iridocorneal endothelial syndrome, etcetera).
3. Previous incisional surgery of the subject eye. Previous uncomplicated clear corneal cataract surgery is allowed \>6 months prior to the surgery.
4. Poor vision in either the study or fellow eye. Poor vision is defined as a corrected vis-ual acuity \<0.6 and/or a visual field loss within the central 10 degrees (with exception of a superior altitudinal defect).
5. Any ocular comorbidities that could affect the visual field. (e.g. diabetic retinopathy, proliferative retinopathy, aphakia, degenerative visual disorder not associated with glaucoma)
6. Chronic or recurrent uveitis.
7. Need for glaucoma surgery combined with other ocular procedures or anticipated need for additional ocular surgery.
8. Anatomical factors that increase the risk of complicated surgery (due to previous trauma, anatomical abnormalities, anterior synechiae or previous cyclodestructive procedure).
9. Conditions that increase the risk of endophthalmitis.

   * Current ocular, adnexal or periocular infections (e.g., untreated blepharitis)
   * Immune compromised patients including the use of topical or systemic steroids for an indication other than the surgery within 3 months of the procedure (this would not include the use of inhaled or dermatologic steroids), chemotherapy within 6 months of the procedure.
   * Iodine allergy
   * Unwilling to discontinue contact lens after surgery
10. Contraindication or allergy to mitomycin C.
11. Any contraindication to tube placement (e.g. shallow anterior chamber, insufficient endothelial cell density).
12. Use of oral hypotensive glaucoma medications for treatment of the fellow eye.
13. Prior ocular laser treatment within 3 months of the surgery, increasing the risk of in-flammation in the eye.
14. Corneal thickness \<450um or \>620microns.
15. Conditions associated with elevated episcleral venous pressure such as active thyroid orbitopathy.
16. Among patients in whom both eyes are eligible only the first eye is undergoing surgical treatment is enrolled in the study.
17. Participation in another clinical study.