Electron microscopic study of toxicity of intravitreal injections of gentamicin in primates

Seven eyes of four young adult cynomolgus monkeys were injected intravitreally with 0.4 mg of gentamicin. One eye was enucleated after 1 day, and two eyes were enucleated after 1 week, 2 weeks and 1 month. The control eye received an intravitreal injection of 0.1 mL of saline and was enucleated after 1 week. All the eyes underwent electroretinography and ophthalmoscopy before and after treatment. No differences were detected by these techniques or by light and electron microscopy between the experimental eyes and the control.