Background/Objectives: To compare the efficacy and safety of Hydrus^® Microstent and iStent inject^® W implants, in combination with phacoemulsification, for lowering intraocular pressure (IOP) in patients with glaucoma in a real-world clinical setting. Methods: This retrospective, single-center study analyzed medical records of glaucoma patients who underwent either Hydrus^® Microstent or iStent inject^® W implantation combined with cataract surgery at the University Hospital Muenster, Germany. Key outcome measures included absolute and relative IOP reduction, reduction in topical antiglaucoma medication use, overall success rate, and complications. A total of 32 eyes were analyzed, 16 in each treatment group, with a 12-month follow-up. Results: Both groups demonstrated significant postoperative IOP reduction (Hydrus: p < 0.001; iStent inject^® W: p = 0.032). The Hydrus group achieved significantly greater relative IOP reduction compared to the iStent inject^® W group (p = 0.043). The Hydrus group also showed a significant reduction in daily antiglaucoma medication use (p = 0.002), whereas the iStent inject^® W group did not achieve statistical significance in this regard (p = 0.054). The overall success rate was higher in the Hydrus group (38%) than in the iStent inject^® W group (13%), though the difference was not statistically significant (p = 0.102). No device-related complications were observed in either group. Conclusions: The Hydrus^® Microstent demonstrated superior IOP reduction and a more significant reduction in the need for antiglaucoma medications compared to the iStent inject^® W in a real-world setting. These findings support the use of the Hydrus implant as an effective and safe micro-invasive glaucoma surgery (MIGS) option for patients with mild to moderate POAG. Further studies with larger patient populations and long-term follow-up are warranted to confirm the efficacy in patients with PEX and advanced glaucoma.

Introduction: Glaucoma, one leading cause of irreversible vision loss worldwide, is primarily caused by elevated intraocular pressure (IOP). Recently, minimally invasive glaucoma surgeries (MIGSs) have become popular due to their shorter surgical times, tissue-sparing nature, and faster recovery. One such MIGS, the Hydrus^® nickel–titanium alloy Microstent, helps lower IOP by improving aqueous humor outflow. The NIDEK GS-1 automated 360° gonioscope provides advanced imaging of the chamber angle for evaluation and documentation. The aim of this study was to test automated 360° gonioscopy for the detection of postoperative positional variations after Hydrus^® Microstent implantation. This study is the largest to date to evaluate post-op positioning of the Hydrus^® Microstent using the NIDEK GS-1. Materials and Methods: This study analyzed postoperative outcomes and stent location in eyes diagnosed with mild to moderate glaucoma that underwent Hydrus^® Microstent implantation with or without phacoemulsification. Patients with prior IOP-lowering surgery or vitrectomy were excluded. Analyses of the postoperative Hydrus^® Microstent position were based on the evaluation of automated 360° gonioscopy images. Results: Twenty-three eyes were included in the study, and all showed a reduction in IOP and a decrease in antiglaucomatous drop use postoperatively. Postoperative gonoscopic images showed variations in implant position. In all cases, the proximal inlet was clearly visible in the anterior chamber. The degree of protrusion into the anterior chamber was variable. The distal tip of the stent was visible behind the trabecular meshwork in Schlemm’s canal in five cases, in the anterior chamber in one case, and not visible in seven cases. In no case did postoperative alterations in the position of the implant lead to explantation. Conclusions: This study demonstrated that the Hydrus^® Microstent can effectively lower IOP even in the presence of postoperative positional variations. Automated 360° gonioscopy was found to be a useful tool to verify and document the postoperative position of the implant. Positional changes did not require device explantation in any of the cases evaluated.