ABSTRACT
Drug delivery systems using biodegradable polymers can provide a significant advantage over nonbiodegradable systems because the entire device is eventually absorbed by the body, eliminating the need for subsequent removal. Several different intraocular drug delivery systems using biodegradable polymers such as microspheres, intraocular implants, scleral plugs, and intrascleral implants have been developed. All intraocular disorders that require systemic administration or frequent local administration of the drug may be appropriate for these biodegradable systems. The scleral plug is a device that is implanted through a sclerotomy at the pars plana; it releases the drug intravitreally. Experimental cytomegalovirus retinitis was induced by intravitreal injection of human cytomegalovirus solution. Experimental proliferative vitreoretinopathy (PVR) was induced by intravitreal injection of fibroblasts in the pigmented rabbit eye. Scleral plugs have been tested in a rabbit model of PVR. For these experiments, scleral plugs composed of 99% poly-lactic acid and 1% of adriamycin were prepared.
