Preliminary outcomes of PreserFlo^® microshunt implantation in patients with primary open-angle glaucoma

PURPOSE. To evaluate preliminary outcomes of PreserFlo^® drainage system implantation for glaucoma treatment in terms of safety and efficacy.
METHODS. In this open prospective study, 9 patients (9 eyes), including 7 men and 2 women, diagnosed with primary open-angle glaucoma were examined and underwent surgery. All patients underwent implantation of the PreserFlo^® drainage system. The average age of the patients was 74.1±11.3 (59–89) years. Standard ophthalmological examinations were performed preoperatively and at 1 day, 7 days, 1 month, and up to 5 months postoperatively. The maximum follow-up period was 5 months.
RESULTS. No intraoperative complications were observed in the early or late postoperative periods. One patient underwent needling of the filtration bleb postoperatively.
A pronounced hypotensive effect was noted in all patients one week after surgery, which persisted in seven out of nine patients for up to two months. Two patients experienced a gradual increase in intraocular pressure (IOP) to 20–23 mm Hg, necessitating additional topical hypotensive therapy. All patients exhibited an improvement in both corrected and uncorrected visual acuity at the longest follow-up. Given the severity of the patients' conditions (multiple previous surgeries and maximal medical therapy), surgical outcomes were categorized as "complete success" and "relative success."
CONCLUSION. This study presents the first short-term (up to 5 months) analysis of the outcomes of PreserFlo^® drainage device implantation in patients with primary open-angle glaucoma in the Russian Federation. Preliminary findings indicate that the device is both effective and safe. Further studies with a larger patient cohort are required to assess long-term outcomes.

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