%0 Journal Article
%T Intravitreal Devices for the Treatment of Vitreous Inflammation
%A John B. Christoforidis
%A Susie Chang
%A Angela Jiang
%A Jillian Wang
%A Colleen M. Cebulla
%J Mediators of Inflammation
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/126463
%X The eye is a well-suited organ for local delivery of therapeutics to treat vitreous inflammation as well as other pathologic conditions that induce visual loss. Several conditions are particularly challenging to treat and often require chronic courses of therapy. The use of implantable intravitreal devices for drug delivery is an emerging field in the treatment of vitreous inflammation as well as other ophthalmologic diseases. There are unique challenges in the design of these devices which include implants, polymers, and micro- and nanoparticles. This paper reviews current and investigational drug delivery systems for treating vitreous inflammation as well as other pathologic conditions that induce visual loss. The use of nonbiodegradable devices such as polyvinyl alcohol-ethylene vinyl acetate polymers and polysulfone capillary fibers, and biodegradable devices such as polylactic acid, polyglycolic acid, and polylactic-co-glycolic acid, polycaprolactones, and polyanhydrides are reviewed. Clinically used implantable devices for therapeutic agents including ganciclovir, fluocinolone acetonide, triamcinolone acetonide, and dexamethasone are described. Finally, recently developed investigational particulate drug delivery systems in the form of liposomes, microspheres, and nanoparticles are examined. 1. Introduction The eye is a model organ for the implantation of devices that provide long-lasting infusion of a therapeutic agent. It is easily accessible for implantation of such a device and success of therapy is measurable objectively by direct visualization of the intraocular structures and by patient responsiveness. The treatment of posterior uveitis and vitreous inflammation usually involves a chronic course of therapy often over a period of years. Topical agents require frequent administration which is often impractical for patients. Sub-Tenon¡¯s and intravitreal steroid injections also can require frequent retreatment to adequately control disease. Treatment with powerful systemic corticosteroid and immunomodulatory agents most often have poor vitreous penetration and can be associated with severe systemic side effects [1]. Implantable devices offer an alternative therapeutic approach that can circumvent many challenges of these other modes of therapy. The first implantable device for clinical use was developed in 1992 [2]. Vitrasert, a nonbiodegradable implant, delivers ganciclovir into the eye for the treatment of acquired-immunodeficiency-syndrome (AIDS)-related cytomegalovirus (CMV). Newer biodegradable implantable devices can provide sustained
%U http://www.hindawi.com/journals/mi/2012/126463/