Glaucoma Services

WHAT IS GLUCOMA ?

Glaucoma is a disease of the major nerve of vision, called the optic nerve. The optic nerve receives light from the retina and transmits impulses to the brain that we perceive as vision. Glaucoma is characterized by a particular pattern of progressive damage to the optic nerve that generally begins with a subtle loss of side vision (peripheral vision). If glaucoma is not diagnosed and treated, it can progress to loss of central vision and blindness

Glaucoma is usually, but not always, associated with elevated pressure in the eye (intraocular pressure). Generally, it is this elevated eye pressure that leads to damage of the eye (optic) nerve. In some cases, glaucoma may occur in the presence of normal eye pressure (Low tension Glucoma). This form of glaucoma is believed to be caused by poor regulation of blood flow to the optic nerve.

WHAT CAUSES GLUCOMA ?

Elevated pressure in the eye is the main factor leading to glaucomatous damage to the eye (optic) nerve. The eye is firm and round, like a basketball. Its tone and shape are maintained by a pressure within the eye (the intraocular pressure), which normally ranges between 10 and 21 mm (millimeters) of mercury. When the pressure is too low, the eye becomes softer, while a too high pressure causes the eye to become harder. It turns out that the optic nerve is the most susceptible part of the eye to high pressure because the delicate fibers in this nerve are easily damaged.

WHAT ARE THE RISK FACTORS ?

Glaucoma is often called "the sneak thief of sight." This is because, as already mentioned, in most cases, the intraocular pressure can build up and destroy sight without causing obvious symptoms

The major risk factors include:

• Age over 45 years

• Family history of glaucoma

• Black racial ancestry

• Diabetes

• History of elevated intraocular pressure

• Nearsightedness (high degree of myopia), which is the inability to see distant objects clearly

• History of injury to the eye

• Use of steroids, either in the eye or systemically (orally or injected)

• Farsightedness (hyperopia), which is seeing distant objects better than close ones (Farsighted people may have narrow filtering angles, which predispose them to acute (sudden) attacks of closed-angle glaucoma.)

• African or Caribbean origin (people of African or Caribbean origin are more at risk of developing glaucoma, and at a younger age.)