Minimally Invasive Glaucoma Surgery: A Review of the Literature

Abstract

Minimally invasive glaucoma surgery (MIGS) has emerged as a novel approach in the glaucoma treatment spectrum, offering a range of diverse procedures and devices aimed at reducing intraocular pressure (IOP). MIGS can be broadly classified into several categories: those that enhance trabecular outflow (Trabectome, iStent, Hydrus Microstent, Kahook Dual Blade, high frequency deep sclerotomy, and gonioscopy-assisted transluminal trabeculotomy), those that augment suprachoroidal outflow (CyPass Microstent and iStent Supra), those that target Schlemm's canal (TRAB360 and the OMNI Surgical System, Streamline, and Ab Interno Canaloplasty), and conjunctival bleb-forming procedures (EX-PRESS Glaucoma Filtration Device, Xen Gel Stent and PreserFlo MicroShunt). MIGS is considered to have a shorter surgical time and fewer severe complications when compared to traditional glaucoma surgeries such as trabeculectomy and glaucoma drainage device implantation (Ahmed, Baerveldt, and Molteno valves). This literature review comprehensively examines the distinct MIGS devices and procedures, their underlying mechanisms, and clinical outcomes, emphasizing the importance of evaluating the efficacy and complications of each approach individually. As the field of MIGS continues to evolve, it is crucial to prioritize high-quality, long-term studies to better understand the safety and effectiveness of these innovative interventions in glaucoma management.

Keywords: MIGS; conjunctival bleb-forming procedures; glaucoma; intraocular pressure; literature review; minimally invasive glaucoma surgery; suprachoroidal outflow; surgical advances; trabecular outflow.

Figure 1

Illustration depicting the coronal cross-section of the anterior segment of the eye, highlighting the anatomic localization of each minimally invasive glaucoma surgery (MIGS) device category, including subconjunctival shunts, suprachoroidal outflow, as well as Schlemm’s canal targeted and trabecular outflow devices. ABiC: Ab Interno Canaloplasty; GATT: gonioscopy-assisted transluminal trabeculotomy; HDFS: high-frequency deep sclerotomy.