Evaluation of bleb characteristics after implantation of the EX-PRESS™ glaucoma filtration device.
OBJECTIVE
To compare bleb survival and histology after implantation of the EX-PRESS™ glaucoma filtration device versus silicone tubes in a rabbit model of filtration surgery.


METHODS
Glaucoma filtration surgery was performed on one eye each of twelve New Zealand white rabbits. Eyes were randomized to implantation with the EX-PRESS™ filtration device (n=6) or a silicone tube (n=6). Bleb vascularity was evaluated at three and six weeks using a standard scale. At 6 weeks, eyes were enucleated and a histologic analysis was performed. Bleb survival was also recorded for the two groups.


RESULTS
Histologically, a thin capsule consisting of mild fibroblast proliferation associated with intercellular collagen was present around both implants. Both groups demonstrated a mild infiltration of plasma cells and polymorphonuclear leukocytes. Bleb vascularity was similar between both groups at three and six weeks post-operatively. Bleb survival between the two groups was not significantly different.


CONCLUSIONS
Similar outcomes were noted after glaucoma filtration surgery using either silicone tubes or the EX-PRESS™ glaucoma filtration device in this rabbit model. Both implants appear to be relatively inert with little difference in biocompatibility and bleb survival.
University of Colorado, Department of Ophthalmology, Aurora, CO 80045, USA.
Ashley E
AE
Laing
Leonard K
LK
Seibold
Jeffrey R
JR
SooHoo
Malik Y
MY
Kahook
D000818:Animals; D001768:Blister / Q000209:etiology* / Q000473:pathology; D018463:Filtering Surgery / Q000009:adverse effects* / Q000295:instrumentation*; D005901:Glaucoma / Q000601:surgery*; D020327:Glaucoma Drainage Implants / Q000009:adverse effects*; D011182:Postoperative Care; D019919:Prosthesis Implantation; D011817:Rabbits