Concentration of Tobramycin in the Cornea and Sclera After Subconjunctival Injection of Negatively-charged Liposome Encapsulated Tobramycin in Rabbits

ABSTRACT

Bacterial keratitis is a common ophthalmic disease. Recently, topical and subconjunctival therapy were equally effective in reducing the number of viable bacteria in experimental corneal ulcers. Subconjunctival injection produced high but transient concentrations followed by persistent low levels. In contrast, eyedrops produced moderate but sustained concentrations throughout the treatment period. Liposomes are small, biodegradable lipid vesicles with an aqueous core. Incorporation of drugs into liposomes provides a convenient way to retard their release from a relatively inert depot without changing the intrinsic characteristics of the agents.