Abstract
Purpose:
FocalSeal® (FS) is an absorbable polyethylene glycol based synthetic hydrogel. A blue-green light makes FS harden by photopolymerization. The aim of this study was to investigate the efficacy of the intra-operative using FS for glaucoma filtration surgery in rabbit’s eyes.
Methods:
There were two groups in this study. The first group included 9 rabbits. The conjunctiva in the left eyes was incised from limbus and the sclera was revealed, and FS was spread above the sclera, and then, after photopolymerization the conjunctiva was closed. In the right eyes, the conjunctiva was incised and simply closed (control). In the other group (6 rabbits included), a fornix-based filtration surgery with silicone tube sutured under the scleral flap was done in the left eye of 6 rabbits. In 3 of them, the seat of hardened FS was placed over the filtration site. In the other 3 eyes, the seat was not placed. Intraocular pressure measurements and bleb evaluations using ultrasound biomicroscopy (UBM) were performed. Six eyes from 3 rabbits in the first group were each enucleated 2, 4, 6 weeks after the surgery. In the second group, the left eyes of 6 rabbits were enucleated 4 weeks after surgery. Histopathologic evaluations of the surgical area were done in all enucleated eyes.
Results:
In the first group, FS was remained in the subconjunctival spaces with inflammatory cells 2 weeks after the surgery. There was no FS observed in 4 weeks after the surgery, although there was a small subconjunctival space. In 6 weeks after the surgery, there were more Masson trichrome staining-positive collagen deposits in the subconjunctival tissues in the control than in the FS treated eyes. In the second group, postoperative IOPs of the FS treated eyes were lower than that of non-treated eyes, although there was no significant difference. The subconjunctival filtration spaces were detected by both UBM and histopathology in the FS treated eyes, but not in the control eyes. There was no remarkable difference in the immunohistochemical staining by anti-α-SMA antibody between FS and control. By anti-Vimentin antibody staining, the connective tissues of the bleb in the control eyes stained stronger than those in the FS treated eyes.
Conclusions:
FocalSeal® used in the subconjunctival space could be a useful adjunctive substance to keep the filtering route in glaucoma filtration surgerys in rabbits.
Keywords: 637 pathology: experimental •
421 anterior segment •
765 wound healing