A Trial of Hydrus Microstent Versus Goniotomy

Inclusion Criteria: * Visually significant cataract planned for surgery * Mild to moderate open-angle glaucoma, including pigmentary glaucoma and pseudoexfoliation glaucoma * Mild stage glaucoma includes glaucomatous optic neuropathy and visual field mean deviation better than -6.0 dB, with no points in the central 5 degrees \<15 dB * Moderate stage glaucoma includes: 1) glaucomatous optic neuropathy and visual field mean deviation equal to or worse than -6.0 dB but no worse than -12.0 dB and no central 5 degree points \<15 dB or 2) mean deviation -12.0 dB or better with 1 central 5 degree point \<15 dB * Medicated IOP between 10 to 31 mm Hg, inclusive, at time of decision for surgery * Willing and able to understand and provide informed consent * Willing and able to attend postoperative examinations per protocol schedule Exclusion Criteria: * Prior argon laser trabeculoplasty, laser peripheral iridotomy, incisional glaucoma surgery, or cyclophotocoagulation * Selective laser trabeculoplasty within 90 days of study enrollment * Iridotrabecular contact for 180 degrees or greater * Peripheral anterior synechiae in nasal or inferior angle * Best corrected visual acuity worse than 20/200 * Phacodonesis on pre-operative examination * Vitreous in anterior chamber on pre-operative examination * Nanophthalmos * Anti-platelet and anticoagulant medications other than aspirin 81mg daily * Active treatment for another ophthalmic condition in either eye (e.g., anti-VEGF injections, steroids for corneal transplant) * Abnormality in study eye that could affect tonometry * Glaucoma diagnosis other than the above * Normal tension glaucoma * Conditions that can cause elevated episcleral venous pressure (e.g., Sturge-Weber syndrome, Graves disease, retrobulbar tumor) * History of uveitis in either eye * Inability to complete gonioscopy examination * Use of oral steroids within 90 days or anticipated use of oral steroids * Oral medications that can affect IOP, including oral carbonic anhydrase inhibitors such as acetazolamide and methazolamide * History of steroid-associated IOP elevation * Medically unfit for attending planned study visits * Involvement in another interventional research study