Glaucoma

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Glaucoma is the name of a group of eye diseases that affects vision. If left untreated glaucoma can eventually cause blindness. Glaucoma is more common in old age, and happens when the optic nerve in the eye is damaged. The two main types of glaucoma are:

open angle glaucoma (or chronic glaucoma), and
acute angle closure glaucoma (or acute glaucoma).

Open angle is the most common type of glaucoma. It develops very slowly and loss of sight is gradual and painless. The nerve fibres at the sides of the eye are the first to be affected, causing a loss of outer (peripheral) vision, which can be hard to notice. Central vision is the last to go.

Open angle glaucoma affects about two in every hundred people over the age of 40. However, this increases over the age of 70 to one person in ten.

Acute glaucoma is less common. The name refers to a narrowed angle between the iris and part of the back of the eye. The reduced angle increases pressure in the eye, causing it to quickly become sore and red.

Occasionally, glaucoma can develop from other eye conditions that cause an increase of pressure in the eye. This is called secondary glaucoma. It may happen as a result of eye injuries or inflammatory eye disease, for example.

Glaucoma is sometimes present from birth. This is called congenital glaucoma and happens when there is a structural abnormality affecting the way fluid drains from the eye.