Aging Disorders of the Eye: Challenges and Approaches for Their Treatment

The proportion of the global population aged 60 years and over is steadily increasing and projected to increase to almost 30 % in 2050. Among the various health problems, eye and vision problems are serious issues in the elderly. These may be manifested as basic functional disabilities or a decline in the receptive, storage, and analytical capacities of the central visual system. The major eye disorders of aging are cataract, age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy. Although there are treatment methods (e.g., medications and surgical interventions) for these conditions, they are still very challenging areas due to the delicate and critical nature of the eye tissues. Compared with drug delivery to other parts of the body, drug delivery to the eye has met with significant challenges posed by various ocular barriers, which are inherent and unique to the ocular anatomy. In addition, in the case of the aging population, there are added difficulties due to multiple diseases and health problems, the several medications being taken together and the physical and psychological difficulties, including disabilities, dependence, fears, and apprehensions: opening packages, swallowing oral medication and/or reading leaflet information, fear of surgery, and device insertion and removal.