The use of Ologen Collagen Matrix implants to treat ocular hypotony developing after trabeculectomy: A case series

Abstract

Purpose: Late hypotony is an undesirable and challenging complication of glaucoma surgery. We describe our use of the Ologen Collagen Matrix to treat late hypotony developing after trabeculectomy. Study design: A retrospective study performed at three eye surgery centers in Brazil. Participants: Eighteen patients who underwent 19 eye surgeries. Intervention: Subconjunctival Ologen was implanted at the trabeculectomy sites to treat over-filtering or leaking blebs in patients experiencing late hypotony after trabeculectomy (obtained 6 months after glaucoma surgery). The primary outcome was the intraocular pressure (IOP); we gathered preoperative data records from 19 Ologen treated eyes and days 1, 7, 30, 60, and 180 postoperatively. The secondary outcomes included visual acuity and macular thickness measured via optical coherence tomography; we compared preoperative data to subsequent ones up to sixth-month-evolution. Results: Over the 6-month period, the IOP rose from 2.89 ± 1.59 mmHg preoperatively to 8.21 ± 3.46 mmHg ( p = 0.0001). Visual acuity improved from 0.33 ± 0.29 to 0.21 ± 0.31 LogMar ( p = 0.0013). Macular thickness fell from 325.62 ± 58.7 to 283.08 ± 47.35 µm ( p = 0.0097). We encountered two complications: one related to suture dehiscence following an ocular trauma and one instance of transitory choroidal detachment. Conclusion: Subconjunctival Ologen implants preserved bleb function and successfully treated post-trabeculectomy hypotony as revealed by data collected at the 6-month follow-up. Longer follow-up is necessary to confirm long-term efficacy and safety. There are no financial conflicts of interest to disclose.

A Brief Review of Historical and Current Trends in Trabeculectomy

“…40,167,171 The use of Ologen implant has been implemented to treat hypotony by a few retrospective studies with 63% to 87% success in IOP improvement without additional intervention and improved bleb morphology. 172,173 Encapsulated Bleb (Tenon Cyst) Encapsulated blebs are domeshaped elevations with thickened connective tissue and vascular engorgement at the sclerostomy site. They usually occur 2 to 8 weeks after surgery and are associated with elevations in IOP.…”

“…More recently, studies have demonstrated improvement in vision and anatomical success after surgical intervention (similar approach to the repair of bleb leaks) for hypotony maculopathy 40,167,171 . The use of Ologen implant has been implemented to treat hypotony by a few retrospective studies with 63% to 87% success in IOP improvement without additional intervention and improved bleb morphology 172,173 …”