The iStent® MIGS family: IStent®, iStent Inject®, and iStent Supra®

Abstract

Microinvasive glaucoma surgeries or MIGS, an acronym coined by Ike Ahmed, represents a fundamental shift in glaucoma surgical philosophy. MIGS exploit existing physiologic outflow pathways allowing both rapid placement and visual recovery. The surgeon interacts with small anatomic functional structures in a minimally destructive manner. The first two Glaukos devices target trabecular outflow (iStenttm (G1) and iStenttm inject (G2)). The third targets uveoscleral outflow (iStenttm Supra (G3)). Theoretical modeling and ex vivo studies were used to study changes in trabecular outflow facility with multiple trabecular stents. This question is being studied clinically and 4000 iStentstm of all types in total have been placed in over 30 studies over the past 10 years. Two trabecular or two uveal scleral stents seem most favorable in terms of risks, costs, and effectiveness. There is also some advantage to using both trabecular and uveal scleral stents in eyes requiring lower target pressures.