Management of refractory glaucoma in a post-keratoplasty eye with PRESERFLO MicroShunt sulcus implantation: A case report

A 65-year-old pseudophakic male with bilateral glaucoma and two previous PKPs in the left eye presented with uncontrolled IOP (35.2 mmHg by Goldmann applanation tonometry) despite maximal topical therapy. The anterior segment showed extensive PAS reaching the keratoplasty edge, with no safe landing zone for an anterior chamber tube. Refractory secondary glaucoma in a post-keratoplasty pseudophakic eye was diagnosed. A PRESERFLO MicroShunt (Santen Pharmaceutical Co., Ltd., Osaka, Japan) was implanted in the ciliary sulcus through a modified scleral tunnel 6 mm posterior to the limbus, with intraoperative mitomycin C. Initial IOP reduction was followed by progressive bleb fibrosis requiring three subconjunctival 5-fluorouracil revisions. At 9-month post-operative follow-up, IOP was 8.8 mmHg on one topical medication – a 75.21% reduction from baseline and a qualified success by World Glaucoma Association criteria – with a clear graft and ongoing corneal suture removal. Ciliary sulcus implantation of the PRESERFLO MicroShunt is a feasible filtering option in post-keratoplasty pseudophakic eyes with obliterated peripheral angles, and early antifibrotic bleb revision is critical for preserving long-term filtration success.