Histologic Studies of the Ahmed Implant with Mitomycin C in a Rabbit Model

Kook, Michael S; Jong, Sung Hung; Kim, Bohng Hee

Abstract

To increase the success rate of intraocular pressure control in recalcitrant glaucoma, Ahmed glaucoma shunt has been used recently. Application of mitomycin C(MMC) during Ahmed implantation may be speculated to increase the success rate by decreasing the fibroblast proliferation and colagen deposition in the filtering capsule. To find out histological change with the use of MMC in the capsule of seton implant, a rabbit model of the Ahmed implant was created to obtain a serial histological specimens over 6 months. Ahmed S1 implant were implanted in 10 normal white rabbits. Five rabbits were treated with 0.04% MMC solution during the implantation under subtenon space(group 1) and the remaining ones were not(group 2). The rabbits were sacrificed at 1, 3, and 6 months to obtain histological specimen of the bleb capsules in each group. Light microscopic examinations were performed after hematoxylin and eosin staining. In group 1(MMC application group), the thickness of fibrous capsule was 0.6mm at 1 month, 0.48mm at 3 months, and 0.4mm at 6 months serially. The number of fibroblasts was 139/mm3 at 1 month, and 82/mm3 at 6 months. In group 2, the capsule thickness was not significantly different compared with roup 1 at 6 months. IN conclusion, during the period over 6 months period, there was no significant difference in thickness of bleb capsule in the two groups although the number of fibroblasts was 3 times denser in group 2 than in group 1.