Cataract - A clouding of the normally clear lens restricts the amount of light entering the eye, thus impairing vision.

Cornea - The clear, transparent outer portion of the front of the eye that provides most of the eye's focusing power.

Corneal Opacification (CO) - A clouding or scarring of the normally transparent cornea, that diminishes the amount of light entering the eye, impairing vision. Corneal opacification can occur as a result of bacterial, fungal or viral infections, or from trauma to the eye.

Diabetic Retinopathy - This complication of diabetes is typically classified into two stages, Non-Proliferative Diabetic Retinopathy (NPDR) and Proliferative Diabetic Retinopathy (PDR).

Fast-Track Designation - A designation made by the FDA for a new drug or biologic intended for the treatment of a serious or life-threatening condition that demonstrates the potential to address unmet medical needs for the condition. Fast track designation drugs are eligible for expedited review by the FDA.

Hyaluronidase - A group of naturally occurring enzymes that digest certain forms of carbohydrate molecules called proteoglycans. The primary role of hyaluronidase is to digest proteoglycans such as hyaluronan, hyaluronic acid and chondroitin sulphate, substances that partly serve as connective tissues in various parts of the body, including the eye. For over 50 years, physicians have used a much less purified form of hyaluronidase safely and extensively to enhance the absorption of local anesthetics.

Keratoconus - A progressive disease of the eye in which the cornea becomes progressively thinner and the development of an irregular, cone-like corneal protrusion occurs. As the disease progresses, vision becomes increasingly distorted.

Non-Proliferative Diabetic Retinopathy (NPDR) - A complication of diabetes in the early stage of diabetic retinopathy that occurs when normal blood vessels in the retina are damaged due to diabetes and swell and to leak fluid and small amounts of blood into the eye.

Ophthalmology - The medical specialty that deals with the anatomy, function, pathology and treatment of the eye.

Posterior Vitreous Detachment (PVD) - The separation of the vitreous humor from the retina, which many retinal specialists believe may be beneficial in the early treatment of diabetic retinopathy to the degree that it can delay or stop the progression of the disease.

Proliferative Diabetic Retinopathy (PDR) - The latter stage of diabetic retinopathy in which new, abnormal blood vessels begin to grow on the surface of the retina in response to widespread closure of normal retinal blood vessels due to diabetes. These new, abnormal blood vessels do not restore normal blood flow to the retina and can cause vitreous hemorrhage, detachment of the retina and permanent vision loss.

Proteoglycans - A type of carbohydrate molecule that serves primarily as connective tissue in various parts of the body, including the eye.

Retina - The nerve layer that lines the back of the eye. The retina senses light and transmits impulses through the optic nerve to the brain.

Vitrectomy - An invasive surgical procedure during which the vitreous humor is excised and removed and replaced with a clear fluid.

Vitreous Humor - The clear gel-like substance that fills the back of the eye between the retina and the front portion of the eye.

Vitreous Hemorrhage - The vision-distorting accumulation of blood within the vitreous humor, the majority of cases result from a complication of diabetes, though it can also result from retinal disorders and trauma.

"Watchful Waiting" - The process of monitoring the progress of a vitreous hemorrhage and assessing the ability of the eye to clear the blood on its own and correct the problem without treatment.