What is glaucoma?
Glaucoma is a condition that affects the optic nerve (the ‘wire’ that connects your eye to your brain).
Over time, the nerve fibers that make up the optic nerve die off slowly, leading to very gradual loss of vision. The exact cause of glaucoma remains unknown, however it is often related to elevated pressure inside the eye (intra-ocular pressure). The raised pressure is thought to be caused by either an overproduction of aqueous humour (fluid) inside the eye; or poor drainage of the aqueous out of the eye.
Aqueous humor is required to maintain the shape of the eye (think of the air inside your car tyre) and to provide the structures inside your eye with nutrients. That said, not all cases of glaucoma are a result of raised pressure and there are cases of normal tension glaucoma where the pressure inside the eye remains normal but signs of optic nerve damage are still present.
There is no way of knowing you have glaucoma; unlike other eye conditions, there is usually no pain or symptoms associated with the condition. There is vision loss, but this only manifests itself when the condition is in its advanced stages and it may then be too late to do anything about it.
The best way to pick up glaucoma is to attend for regular eye examinations; your optometrist will shine a light inside your eye and observe the optic nerve - if anything looks suspicious they can refer you on to an ophthalmologist for further checks. They can also measure the pressure inside your eye using a tonometer to make sure it’s within the normal range.
Although there is no cure for glaucoma, it can be managed successfully if picked up early. Treatment ranges from the use of eye drops to minor eye surgery. Eye drops consist of either beta-blockers or prostaglandins; beta-blockers work by reducing the amount of aqueous being produced inside the eye, whereas prostaglandins open the drainage structures inside the eye allowing for better outflow of aqueous. Sometimes a laser beam may be used to create extra ‘holes’ to improve outflow.
Glaucoma is a sight-threatening condition and its effects can take months if not years to develop. However, when picked up early, it can be managed successfully and complete sight loss can be prevented. If it goes undetected, it can lead to irreversible sight loss.