Coupled with an improved ability to recognize early warning signs of glaucomatous progression, the continued evolution of the MIGS class has expanded the opportunities for earlier intervention. In many instances, initiating medical therapy in the first line for treatment-naïve patients at risk for progression is no longer the most desirable option. Indeed, as quality of life issues and cost concerns become increasingly important, interventions that obviate the need for the daily instillation of drop therapy have grown in popularity.
The demonstrated safety of the MIGS class is the biggest factor driving the shift toward procedural and surgical management of glaucoma. Because the current lineup of MIGS is intended for use among individuals with mild to moderate glaucoma (and in some cases, performed at the same time as cataract surgery), the extent of IOP lowering they deliver is acceptable. However, there is still unmet treatment need for patients requiring more robust IOP lowering (such as patients with moderate glaucoma and those with mild glaucoma but at high risk for progression). For these individuals, traditional MIGS may not deliver enough efficacy, whereas filtering surgeries entail too great a risk for failure or complications to be a suitable consideration.
A novel MicroShunt device (Santen) intended for implantation via an ab externo approach during a standalone MIGS procedure offers significant potential to expand access to safe and effective procedural options for a wide assortment of patient types. Using a design that incorporates principles determined by the Poiseuille equation,1 the device maintains a patent connection between the anterior chamber and the subconjunctival space while reducing the potential for hypotony. Further, the resulting bleb is located posteriorly, making it less susceptible to infection and conferring advantages for patients’ comfort and aesthetics.
In the following articles, leading glaucoma surgeons and researchers share insights on current unmet treatment needs in glaucoma, the role and rationale of subconjunctival MIGS, and future research that will help better elucidate the utility of targeting the alternative outflow pathway.
1. Pinchuk L, Riss I, Batlle JF, et al. The use of poly(styrene-block-isobutylene-block-styrene) as a microshunt to treat glaucoma. Regen Biomater. 2016;3(2):137-142.