Clinical investigation of new glaucoma procedures

This article reviews recent studies evaluating the efficacy and complication profiles of novel glaucoma procedures promoting aqueous outflow.

Literature from the 2015 to 2016 review period includes abundant data regarding new and emerging glaucoma procedures. Notable findings from recent randomized clinical trials include titratability of intraocular pressure with multiple trabecular microbypass stents (iStent; Glaukos, Laguna Hills, California, USA) and greater reduction in intraocular pressure and medication usage following intracanalicular scaffolding (Hydrus Microstent; Ivantis Inc., Irvine, California, USA) combined with phacoemulsification vs. phacoemulsification alone. A supraciliary microstent (CyPass Micro-Stent; Transcend Medical, Inc., Menlo Park, California, USA) received approval from the Food and Drug Administration after a pivotal trial demonstrated its efficacy and safety. Early studies of investigational subconjunctival filtering devices (XEN Gel Stent; AqueSys, Inc., Aliso Viejo, California, USA and InnFocus MicroShunt; InnFocus Inc., Miami, Florida, USA) offer promising evidence, but late complications are as yet unknown.

Newer glaucoma procedures targeting different aqueous outflow pathways have improved the safety profile of glaucoma surgery while preserving modest efficacy. Most can be combined with phacoemulsification, allowing for simultaneous treatment of comorbid cataract and glaucoma. Well-designed randomized clinical trials with extended follow-up remain necessary to evaluate the long-term efficacy and late complications of these novel procedures.