Aqueous Shunts with Extraocular Reservoir for Open-Angle Adult Glaucoma A Report by the American Academy of Ophthalmology

Purpose: To evaluate the recently published literature on the efficacy and safety of the use of aqueous shunts with extraocular reservoir for the management of adult open -angle glaucomas (OAGs). Methods: A search of peer -reviewed literature was last conducted in April 2023 of the PubMed database and included only articles published since the last aqueous shunt Ophthalmic Technology Assessment, which assessed articles published before 2008. The abstracts of these 419 articles were examined, and 58 studies were selected for full -text analysis. After inclusion and exclusion criteria were applied, 28 articles were selected and assigned ratings by the panel methodologist according to the level of evidence. Twenty-five articles were rated level I and 3 articles were rated level II. There were no level III articles. Results: Implantation of aqueous shunts with extraocular reservoir can lower intraocular pressure (IOP) by between one-third and one-half of baseline IOP, depending on whether it is undertaken as the primary or secondary glaucoma surgery. Success rates for aqueous shunts were found to be better than for trabeculectomies in eyes with prior incisional surgery. Conversely, in eyes without prior incisional surgery, implantation of aqueous shunts was found to have an overall lower success rate as the primary glaucoma procedure compared with trabeculectomy. Although both valved and nonvalved aqueous shunts with extraocular reservoir were effective, the nonvalved device generally achieved slightly lower long-term IOPs with fewer glaucoma medications and less need for additional glaucoma surgery. Both devices slow the rates of visual field progression with efficacy comparable with that of trabeculectomy. Early aqueous humor suppression after aqueous shunt implantation is recommended for the management of the postoperative hypertensive phase and long-term IOP control. No strong evidence supports the routine use of mitomycin C with aqueous shunt implantation for OAG. Conclusions: Implantation of aqueous shunts with extraocular reservoir, including valved or nonvalved devices, has been shown to be an effective strategy to lower IOP. Strong level I evidence supports the use of aqueous shunts with extraocular reservoir by clinicians for the management of adult OAG. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. (c) 2023 by the American Academy of Ophthalmology