Spotlight on Schlemm’s Canal MicroStent Injection in Patients with Glaucoma

Abstract

Minimally invasive glaucoma surgery (MIGS) has revolutionized glaucoma care with its favorable safety profile and ability to delay or minimize the need for traditional, bleb-based procedures. Microstent device implantation is a type of angle-based MIGS, which reduces intraocular pressure (IOP) through bypass of the juxtacanalicular trabecular meshwork (TM) and facilitation of aqueous outflow into the Schlemm’s canal. Although there are limited microstent devices on the market, multiple studies have evaluated the safety and efficacy of iStent ® (Glaukos Corp.), iStent Inject ® (Glaukos Corp.), and Hydrus ® Microstent (Alcon) in the treatment of mild-to-moderate open-angle glaucoma, with and without concurrent phacoemulsification. This review attempts to provide a comprehensive evaluation of injectable angle-based microstent MIGS devices in the treatment of glaucoma.

First-Generation iStent Bypass Implantation versus ab Externo Canaloplasty Combined with Phacoemulsification in Patients with Primary Open Angle Glaucoma—12-Month Follow-Up

“…An interesting aspect that emerged from the analysis of different studies is that PiS demonstrates a variable IOP-lowering effect [21,[46][47][48]. The average decrease in IOP is reported from 22.9% to 32.9% [22,46,48], with the longest follow-up of 7 years [49]. Several theories have been proposed to account for this variability, including improper surgical placement within the TM, linked to the surgical learning curve [50,51].…”

Five-Year Outcomes of Single Trabecular Microbypass Stent (iStent®) Implantation with Phacoemulsification in Korean Patients

“…All subjects underwent implantation of one iStent ® device between January 2018 and June 2019. Each single-piece, heparin-coated, titanium stent had a length of 1.0 mm, height of 0.33 mm, and snorkel bore diameter of 120 μm [ 4 ]. Briefly, under topical anesthesia using a 0.5% proparacaine eye drop, uncomplicated phacoemulsification was completed through a temporal clear incision with a 2.4-mm keratome.…”

“…Canal-based minimally invasive glaucoma surgery (MIGS) provides advantages, such as quicker visual recovery and sparing of conjunctival tissue for future glaucoma surgeries [ 4 ]. The iStent ® (Glaukos Corporation, Aliso Viejo, CA, USA) is one of the canal-based MIGS device.…”

“…The iStent ® (Glaukos Corporation, Aliso Viejo, CA, USA) is one of the canal-based MIGS device. The first-generation single trabecular microbypass iStent ® , with an internal diameter of 120 µm, and the second-generation iStent ® inject or iStent ® inject W, composed of two stents, each with an internal diameter of 80 µm, were designed to allow direct aqueous flow into Schlemm’s canal, bypassing the trabecular meshwork [ 4 , 5 ].…”