A NEW MODEL OF SUBRETINAL NEOVASCULARIZATION IN THE RABBIT

Purpose. To establish a new model of subretinal neovascularization (SR N) in the rabbit by implanting basic fibroblast growth factor (bFGF)-i mpregnated gelatin microspheres beneath the retina. Methods. Basic fib roblast growth factor-impregnated gelatin microspheres were prepared b y forming a polyion complex between gelatin and bFGF. The microspheres , containing 2.5 mu g of bFGF, were injected into the subretinal space of rabbit eyes (n = 29). Control eyes (n = 10) received bFGF-free gel atin microspheres. Eyes were followed up for 3 days to 8 weeks by opht halmoscopy, photography, fluorescein angiography, light microscopy, an d transmission electron microscopy. Results. Twenty of 24 experimental eyes (83%) showed fluorescein leakage from SRN 2 weeks after implanta tion of the bFGF-impregnated microspheres. This leakage continued for 2 to 6 more weeks. In striking contrast, control eyes showed no fluore scein leakage, Histologic examination revealed SRN in all the experime ntal eyes but in none of the control eyes. Conclusions. Subretinal imp lantation of bFGF-impregnated gelatin microspheres induces reproducibl e SRN in the rabbit.