ESTABLISHMENT OF A RABBIT MODEL OF EXTRASCLERAL EXTENSION OF OCULAR MELANOMA

Purpose: To establish an animal model of extrascleral extension of cho roidal melanoma. Methods: Pigmented choroidal tumors were established in nine New Zealand albino rabbit eyes using B16F10 melanoma cell line . The sclerotomy site was not closed in the subgroup of six rabbits wh ere extrascleral extension was desired. For the control group, the scl erotomy site was sutured with 8-0 nylon. Animals were treated with dai ly injections of cyclosporine and followed by serial fundus examinatio ns, color Doppler imaging, and fundus photography, All tumor-bearing e yes were enucleated at the end of the follow-up period and examined fo r extrascleral extension. Results: Extrascleral extension of choroidal melanoma occurred in all six animals with open sclerotomy sites. No e xtrascleral extension was observed in the control group. Color Doppler imaging identified extrascleral extension which was confirmed on gros s histology, Conclusions: Our animal model of extrascleral extension o f choroidal melanoma requires minimal surgery to establish, and is rep roducible and easy to follow with standard diagnostic equipment.