Comparison of Surgical Times for Gonio Lenses and Viewing Systems in iStent Inject^® W Surgery

Background/Objectives: The aim of the study was to investigate the difference in operative times for iStent inject^® W (iStent) implantation based on variations in the gonio lens and with use of a surgical microscope or the NGENUITY^® 1.5 (Alcon Laboratories, Inc. Fort Worth, TX, USA) which is a digitally assisted surgery system). Methods: This retrospective study included patients who underwent iStent implantation performed by the same surgeon at Juntendo University Urayasu Hospital between January 2021 and December 2022. Participants were divided into Group M, which utilized a disposable gonio lens (Ocular Instruments, Washington, DC, USA) and the surgical microscope; Group A, which used Ahmed's DVX Surgical Gonio lens^® (Ocular Instruments) and the surgical microscope; and Group D, which employed the disposable gonio lens and the NGENUITY^® system. The preparation and recovery times were retrospectively compared as the primary outcome across the three groups. Results: Preparation and recovery times were significantly shorter in Group A than those in the other two groups (both p < 0.01). There were no significant differences in preparation (p = 0.968) and recovery times (p = 0.841) between groups M and D. Conclusions: In iStent surgery, preparation and recovery times for angle observation were shorter with the Ahmed gonio lens than with the disposable gonio lens. No difference was observed between the surgical microscope and digitally assisted surgery methods. The Ahmed gonio lens is useful for surgeons who perform cataract surgery through an upper incision.