Effect of Subconjunctival Healaflow in Filtrating Surgery with Preserflo MicroShunt in Primary Open Angle Glaucoma.

: This work aims to clarify whether the subtenon use of the sodium hyaluronate product Healaflow in filtrating surgery with PreserFlo MicroShunt positively influences the early postoperative course in terms of control of intraocular pressure, hypotony, and needling rate. : A retrospective, randomized controlled, interventional, single-center trial was performed at the Ludwig Maximilians-University Munich from January 2024 to July 2024. Only patients with primary open angle glaucoma (POAG) were included. In all patients, a complete ophthalmological examination including best corrected visual acuity (BCVA), automated refraction, and Goldman tonometry was performed at 2 days, 1-4 and 5-8 weeks, and 3-4 and 5-6 months after surgery. Healaflow was injected underneath the tenon during filtrating surgery with PreserFlo MicroShunt in addition to mitomycin C (MMC). The Healaflow group was compared to a control group with POAG patients in which Healaflow was not used during surgery with PreserFlo MicroShunt and MMC. : A total of 45 eyes of 45 patients were included, with 20 eyes in the Healaflow group and 25 eyes in the control group. In both groups, a significant reduction in IOP and medication could be observed: complete surgical success (IOP ≥ 6 mm Hg and ≤17 mm Hg, without surgical complications or complete loss of vision) was reached in 88% of patients in the Healaflow group at the last follow-up. In 95% of patients in the control group, complete success could be observed. The success rates did not significantly differ between the two groups ( = 0.568). Hypotony rates were 35% in the Healaflow and 12% in the control group after two days ( = 0.083); the rates equalized after 1-4 weeks ( = 1). Needling rates were comparable between both groups (25% versus 20%, = 0.731). : PreserFlo MicroShunt implantation with MMC was equally effective in terms of reduction in IOP and medication in both scenarios with additional or without the use of Healaflow. Postoperative hypotony and needling rates did not significantly differ between the two groups. The additional effects of Healaflow on anti-scarring and maintaining space are likely too minimal to cause significant differences in IOP or medication when already treated with MMC.