Abstract
Purpose: :
To compare bleb survival, bleb vascularity and local tissue response after implantation of the EX-PRESSTM glaucoma filtration device versus implanted silicone tubes in a rabbit model of filtration surgery.
Methods: :
Twelve New Zealand white rabbits underwent glaucoma filtration surgery. They were divided into two groups: implantation with the EX-PRESS filtration device (n=6) or a silicone tube (n=6). Bleb survival was recorded for comparison between the two groups. A standard scale was used to evaluate bleb vascularity at three and six weeks post-operatively. The eyes were enucleated and a histologic analysis was performed at six weeks.
Results: :
Both implants were surrounded by a thin capsule consisting of mild fibroblast proliferation and intercellular collagen. The local tissue response consisted of a mild infiltration of plasma cells and polymorphonuclear leukocytes. There was no significant difference in bleb survival between the two groups. Bleb vascularity was similar between both groups at three and six weeks post-operatively.
Conclusions: :
The tissue reaction surrounding both implants consisted of a thin fibrotic capsule with few inflammatory cells. There appears to be little difference in the biocompatibility of these two materials with both being relatively inert.
Keywords: aqueous • anterior segment