Principles and practice of intravitreal application of drugs

Over the last 10 years, the success of anti-vascular endothelial growth factor (VEGF) antibodies for the treatment of neovascular age-related macular degeneration (AMD) has made the use of intravitreal injections for the treatment of posterior segment disease commonplace. The application of drugs into vitreous, as either a direct intraocular injection or in the form of sustained-release devices, is currently the focus of many clinical studies to treat a number of retinal and choroidal diseases. The advantages of this approach are that local treatment bypasses the systemic side effects of a drug and enables more direct control over the dose and duration of drug delivery to the target site. Furthermore, as we gain an increased understanding of the pathophysiological processes in diseases such as vitreomacular traction syndrome and diabetic retinopathy, new pharmacologic treatments have arisen that have the potential to obviate the need for surgical intervention or at least facilitate surgery.