Short-Term Safety and Efficacy of PreserFlo™ Microshunt in Patients with Refractory Intraocular Pressure Elevation After Dexamethasone Implant Intravitreal Injection

Abstract

Background: The PreserFlo™ MicroShunt (PFMS) is a bleb-forming device considered to be less invasive than traditional glaucoma surgery such as trabeculectomy. This study evaluates the 1-year success rates as well as safety profile of PFMS in patients having high intraocular pressure (IOP) and/or glaucoma refractory to drop therapy with a history of prior intravitreal dexamethasone therapy. Methods: A total of 16 eyes after PFMS implantation due to elevated IOP after intravitreal dexamethasone implant (DEX-I) administration were included in this retrospective cohort study. Success rates and secondary outcomes were evaluated. Results: Qualified and complete success rates at 12 months, respectively, were 14/16 and 12/16 eyes for criterion A, 13/16 and 11/16 eyes for B, 13/16 and 11/16 eyes for C, and 6/16 and 6/16 eyes for D. The overall mean (range) preoperative IOP decreased from 27 (16–38) mmHg to 13 (10–17) mmHg at 12 months. BCVA was not significantly different up to 12 months (p = 0.63). The preoperative mean (range) number of medications decreased from 3.56 (2–4) to 0.31 (0–3) at 12 months. One eye underwent needling twice, and two eyes were revised surgically. One patient needed replacement of the PFMS. There were no hypotony-related complications. Conclusions: The PFMS is an effective surgical option for patients with steroid-induced IOP elevation. It demonstrates satisfactory short-term success rates, a reduced need for pressure-lowering eye drops, an excellent safety profile with minimal postoperative care, and a low complication rate. Additional interventions such as needling or revisions were infrequently necessary. However, PFMS may not be the ideal choice for cases requiring a low target pressure (≤12 mmHg).