Cutting Edge Glaucoma - Issue 2

28 • CUTTING EDGE - GLAUCOMA antifibrotic therapy was administered pre-/perioperatively via subconjunctival injection, at the surgeon’s discretion (including type and dose). In the implant alone group, an ab interno approach (described by Vera and Horvath [8]) was used to place the gelatin stent, connecting the anterior chamber to the subconjunctival space. General surgical steps for implantation included creating temporal clear corneal main and side port incisions; filling the anterior chamber with cohesive viscoelastic; inserting the needle tip of the injector through the main incision and advancing across the anterior chamber (toward the superior-nasal quadrant), with needle entry at the desired angle position and advancement through the sclera using a second instrument at the side port to provide stabilization and coun- terforce; visualizing the needle and needle tip bevel in the subconjunctival space; deploying the gelatin stent; removing the injector and viscoelastic; pressurizing the anterior chamber; and creat- ing a subconjunctival bleb with a balanced salt solution. All incisions were hydrated at the end of the surgery. The target for an ideally positioned stent was 1 mm in the anterior chamber, 2 mm in the scleral tunnel, and 3 mm in the subconjunctival space. If incorrectly positioned, the device could be adjusted or exchanged. In the phaco + implant group, phacoemulsification was performed and an intraocular lens was inserted, followed by placement of the gelatin implant if the cataract surgery was success- ful and uncomplicated. If complications that could potentially impact the study results (such as corneal burn, vitreous loss requiring vitrectomy, and placement of an anterior chamber lens) occurred during cataract surgery, the eye was withdrawn from the study. The postoperative treatment regimen was per investigator’s discretion. Recommendations included topical antibiotic (fluoroquinolone or equivalent, preferably BAK-free) QID for 1 week, as well as topical steroid (prednisolone acetate 1% or equivalent, or BAK-free difluprednate 0.05%) QID for ≤ 4 weeks and titrated thereafter based on clinical assessment of postoperative inflammation. If a patient required further IOP lowering postoperatively, the investigator had the option of reintroducing ocular hypotensive medications in a stepwise fashion (i.e., 1 drug class at a time) and/or needling the bleb. Consistent with the American Academy of Ophthalmology’s Preferred Practice Pattern Guidelines [1], needling was part of the standard postoperative care to improve aqueous flow and lower IOP based on the investigator’s clinical assessment of bleb func- tion. Consistent with other recent studies [18, 19], needling was not considered an adverse event (AE) or glaucoma-related secondary surgical intervention (SSI) but was documented as a post- operative procedure; it could be performed at any point in the postoperative period, as believed necessary by the investigator. No specific protocol was mandated, and use of an antifibrotic agent at the time of needling was also left to the investigator’s discretion. Assessments Postoperative visits were scheduled at day 1, weeks 1 and 2, and months 1, 3, 6, 9, 12, 18, and 24. IOP was determined at medicated baseline and each postoperative visit using Goldmann appla- nation tonometry and a masked, two-person method [20]; two consecutive measurements were taken, followed by a third if the first two differed by ≥ 3 mmHg.