RESUMO
Objective To evaluate the security of intravitreal injection with ciproflaxacin to retina. Methods Tweenty-four rabbits were randomly divided into 4 groups with 6 rabbits in each group. 0.1 ml ciproflaxacin in doses of 2 500, 5 000, and 10 000 ?g was intravitreally injected into the rabbits eyes, retrospectively. And 0.1 ml saline solution was injected into the vitreous body of the rats in the control group. Indirect microscope, light microscope and electroretinogram (ERG) were used to observe the changes of ocular fundus. Results Normal results of light microscopy and ultrastructure were found in 250 ?g and 500 ?g groups; irregularly arranged outer and inner nuclear layers, dropsical or even lost ganglion cells, and ultrastructural changes were in 1 000 ?g group. There was no apparent difference of ERG′s a and b amplitudes before and after intravitreal injection with ciproflaxacin in each group. Conclusion Intravitreal injection with ciproflaxacin is safe, and 500 ?g or less is the secure dosage in rabbits' eyes.