accommodation: the ability of the eye to change focus from distant objects to near objects

astigmatism: An optical defect, whereby vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina.

blindness: There is no set definition for blindness. Usually, it is either a total loss of vision, or when there is no possibility of correcting vision through medical intervention. In Australia legal blindness is defined as best corrected visual acuity of 6/60 or below in the better eye.

cataract: A mostly degenerative condition in which the lens of the eye clouds over, obstructing the passage of light to cause vision loss and, potentially, blindness. Cataract surgery involves the removal of the lens, replacing it with a plastic one.

colour blindness: The inability to distinguish between all or certain colours. Colour blindness varies in severity and is often genetically linked.

diabetes: a chronic disease characterised by high levels of blood glucose, caused by an inability to produce or effectively use insulin, a hormone for blood glucose control. Divided into type 1 and type 2 diabetes.

diabetic retinopathy: A disorder of the retinal blood vessels (such as microaneurysms or haemorrhaging), most often found in those with long-standing diabetes.

dilated eye examination: An ocular health check where the pupil is dilated with a topical medication in order for the peripheral areas of the retina at the back of the eye to be examined. Also known as dilated fundus examination.

dry macular degeneration: the more prevalent form of macular degeneration.

general practitioner (GP): A medical practitioner who provides primary comprehensive and continuing care to patients and their families in the community.

hyperopia: The inability of the eye to focus on nearby objects due to the rays of light entering the eye being brought to focus behind the retina. Also called long-sightedness or far-sightedness.

laser: Extremely high powered light pulse used in the treatment of multiple ocular conditions.

macula: part of the eye that is responsible for an individual’s central vision – tasks such as reading, recognising faces or driving

macular degeneration: A progressive deterioration of the macula of the retina (the central inner-lining of the eye). It is often positively related to old age (usually referred to as 'age-related macular degeneration'), and results in a loss of central vision. Has ‘dry’ and ‘wet’ forms.

myopia: A type of refractive error whereby distant objects appear blurred, usually due to light rays entering the eye being focused in front of the retina. Also called short-sightedness or near-sightedness.

neovascular macular degeneration: Also known as wet macular degeneration

ocular-adnexa: bone, muscles, nerves and other tissues surrounding the eye

ophthalmology: The branch of medicine concerned with the study of the eye and the diagnosis and treatment of disorders of the eye.

optometry: The practice of primary eye care, including testing for visual acuity and prescribing treatments for eye disorders.

paracentesis: Intervention or procedure involving perforation of the eye

presbyopia: An age-related condition in which the loss of elasticity of the lens leads to a shift to long-sightedness.

refractive error: The inability of the lens of the eye to focus on an image correctly, such as occurs in far- and near-sightedness.

telehealth: The provision of healthcare services remotely via phone or web programs.

trachoma: an infectious eye disease caused by the Chlamydia trachomatis bacteria that is frequently spread by flies and the lack of good hand and face hygiene. It can scar the surface of the eye and cause blindness in the long-term if left untreated. 

type 1 diabetes: A lifelong autoimmune disease that usually has onset in childhood and adolescence where an individual needs daily insulin replacement to survive.

type 2 diabetes: Occurs when the body becomes resistant to the insulin being produced by the pancreas and/or the amount produced is inadequate to meet the body's needs.

visual acuity: The ability to see clearly and at a distance. It is measured using an eye chart, and is usually expressed as a fraction. For example, 6/60 describes the ability to see objects at 6 metres that the normal eye sees at 60 metres.

visual impairment: A significant limitation of visual capacity, including those with low vision or blindness, usually brought about by degenerative or congenital disorders, or the result of disease or injury.

wet macular degeneration: The less common and more debilitating form of macular degeneration which is characterised by the growth of new and leaky blood vessels under the damaged macula. Also known as neovascular macular degeneration.