[Expanded polytetrafluoroethylene with different pore diameter for keratoprosthesis cell ingrowth and corneal metabolism].
OBJECTIVE
(1). To study the relationship between the different pore diameter of the expanded polytetrafluoroethylene, (ePTFE) and the rate of cellular ingrowth in cornea; (2). To evaluate the influence of implant on corneal metabolism.


METHODS
Two kinds of ePTFE disk with 45 microns and 28 microns pore diameter were implanted after a free-hand intralamellar dissection. The eyes were examined by slit-lamp biomicroscopy up to 7 months postoperatively. The corneas were removed and examined by light and transmission electron microscopy.


RESULTS
Stromal fibroblasts penetrate, proliferate, and synthesize collagen in the pore of these two kinds of ePTFE, while the rate of cellular ingrowth and collagen deposition was greater in the ePTFE with 45 microns pore than 28 microns pore. Lipid deposits occurred in 3 eyes with 45 microns pore and in 5 eyes with 28 microns pore (P > 0.05). Dicks remained in corneas for 7 months without any extrusion in all eyes.


CONCLUSIONS
Stromal fibroblasts can penetrate, proliferate, and synthesize collagen in the pore of both two kind of ePTFE, while cells penetrate greatly in the larger pore. Dicks interfere corneal metabolism in some degree. The ePTFE with 45 microns pore diameter, 200 mm thick, 84% porosity is a suitable material for the skirt of the keratoprosthesis.
Liang
D
D
Zhongshan Opththalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China.
Chen
J
J
Li
Y
Y
Lin
J
J
Chen
Z
Z
D000818:Animals; D003094:Collagen / Q000378:metabolism; D003315:Cornea / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D005347:Fibroblasts / Q000473:pathology*; D011138:Polytetrafluoroethylene; D016062:Porosity; D019736:Prostheses and Implants; D011817:Rabbits
D011138:Polytetrafluoroethylene; D003094:Collagen