3-year safety and efficacy results of PreserFlo™ Microshunt in glaucoma patients: A multicentre European cohort study

Purpose To report three-year outcomes of a multicenter cohort undergoing Preserflo Microshunt surgery (PFMS). Design Retrospective cohort study Methods Retrospective review of 100 consecutive eyes (91 patients) undergoing PFMS from four tertiary-referral glaucoma centers. Primary outcome were success rates. Secondary outcomes included: intraocular pressure (IOP), best-corrected visual acuity, medication, complications and postoperative interventions. Results 100 eyes of 91 patients were included. Qualified and complete success rates (95 % CI) were 80 % (72–87 %) and 56 % (47–65 %) for Criterion A (IOP≤21 mmHg), 75 % (67–83 %) and 55 % (46–65 %) for Criterion B (IOP≤18 mmHg), 44 % (31–50 %) and 39 % (30–49 %) for Criterion C (IOP≤15 mmHg) and 10 % (5–16 %) and 10 % (5–16 %) for Criterion D (IOP≤12 mmHg) respectively. Mean IOP decreased from 23.8 mmHg to 14.1 mmHg (reduction of 35.3 %) after 36 months with a reduction of IOP-lowering agents from 2.52 (0 – 4) to 0.69 (0 – 3). 7 eyes (7 %) needed additional glaucoma surgery. Of these, 3 eyes underwent a glaucoma drainage device and 4 eyes had a trabeculectomy.36 eyes received additional procedures after PFMS implantation. Of these, 14 eyes (14 %) underwent a surgical revision and 12 eyes (12 %) a bleb needling procedure. The complication rate was low: 1 eye developed corneal decompensation and underwent a DMEK after 24 months. 1 eye had a conjunctival erosion requiring a revision surgery. 2 eyes developed a postoperative uveitis that was treated with topical steroids and resolved without further damage. There were no hypotony-related complications. Conclusions PFMS surgery is a safe and effective procedure for reducing IOP and pressure-lowering therapy.