Polyethylene Glycol-Based Synthetic Hydrogel Sealant for Filtration Bleb Leaks: An In Vivo and Histologic Study

PURPOSE: To evaluate the efficacy of polyethylene glycol (PEG)-based synthetic sealant for closing bleb leaks after glaucoma filtration surgery. METHODS: Tube shunt surgery that included implantation of a 22-gauge indwelling catheter and intraoperative mitomycin C was performed in the left eyes of 11 New Zealand white rabbits. Seven days postoperatively, all filtration blebs were perforated with an 18-gauge needle to create a bleb hole. In six rabbits, the holes were covered with the sealant and irradiated with blue-green light for 60 seconds; in the five control rabbits, the holes were untreated. For 3 weeks after the tube shunt surgery, the eyes were checked for bleb leaks, and the intraocular pressure (IOP) was measured in both eyes. Finally, the operated eyes were enucleated for histologic examination. RESULTS: The bleb leaks stopped in the eyes in which sealant was used and persisted in the other eyes. The sealant preserved the bleb function; the IOPs in these eyes were significantly (P < 0.05) lower than the right eyes that did not undergo surgery. Hematoxylin and eosin staining showed that the holes were closed and covered with conjunctival epithelial cells in the eyes in which sealant was applied; the holes were open in the control eyes. Immunohistochemical staining showed that the bleb holes in which the sealant was applied had fewer inflammatory cells. CONCLUSIONS: The PEG sealant has the potential to seal bleb leaks effectively. TRANSLATIONAL RELEVANCE: Application of the PEG sealant can be used as adjunct therapy for bleb leaks in glaucoma surgery.