Prevention of experimental proliferative vitreoretinopathy with daunomycin and triamcinolone based on the time course of the disease

Background: Our previous experiments showed a limited effect of treatment with daunomycin when given at the inflammatory phase of the development of proliferative vitreoretinopathy (PVR) induced by macrophages in rabbits. In the present study, we tested the efficacy of daunomycin when given at the proliferative phase and combined with triamcinolone given separately at the inflammatory phase in the same model. Methods: Four groups of rabbits, 16 animals in each, respectively received 5 mu g daunomycin on day 6; 1 mg triamcinolone immediately after macrophage injection; 1 mg triamcinolone immediately and 5 mu g daunomycin on day 6 (combined drugs); and 0.1 ml saline (controls). Ophthalmoscopy and H-3-thymidline autoradiography were use to evaluate the effects of drugs on traction retinal detachments and cellular proliferation in the vitreous and on the retina. Results: Retinal detachment occurred in 33.3%, 16.1%, 8.3% and 83.3% (P<0.01) of the eyes treated with daunomycin, triamcinolone, combined drugs, and the controls, respectively. Autoradiography revealed significantly decreased numbers of labelled nuclei on days 7 and 14 in daunomycin-treated eyes compared with controls. Significantly decreased numbers of inflammatory cells and labelled cells were noted in eyes treated with triamcinolone and combined drugs. Conclusion: Daunomycin given at the proliferative phase, and combined with triamcinolone given at the inflammatory phase of PVR, can be more effective in preventing PVR development than daunomycin given at the inflammatory phase.