Routes for Drug Delivery to the Retina: Topical, Transscleral, Suprachoroidal and Intravitreal Gas Phase Delivery.

Local drug delivery to the posterior segment, particularly the macula, represents a significant challenge. In this chapter, we review current challenges, barriers and limitations. Due to the local drug delivery to the retina and macula, systemic side effects are limited. In this chapter, we also discuss the historical approaches, key aspects of ideal drug delivery systems, the use of animal models to study pharmacokinetics, and the principles of transscleral, suprachoroidal and gas phase drug delivery.