Glaucoma – what you should know
Here are 5 key points about glaucoma:
- Glaucoma is the leading cause of avoidable blindness worldwide
- Over 300,000 Australians currently suffer from glaucoma
- Around 50% of all sufferers are undiagnosed
- Glaucoma can lead to permanent loss of vision
- Prevention and early detection are essential
What is glaucoma
Glaucoma is the name given to a group of eye conditions that result in damage to the nerve fibres at the back of the eye. This damage is permanent and can lead to irreversible blindness. Although it is more commonly associated with growing old, this condition can occur at any age. Glaucoma is avoidable.
Causes of glaucoma
An increased pressure of the fluid within the eye can progressively damage the optic nerve. The level of pressure in the eye (intraocular pressure or IOP) that results in damage varies between people. Some people can develop this condition with a normal IOP, while others with a high IOP may never develop glaucoma.
Some people have a higher risk. Glaucoma Australia lists the following as having an increased risk of developing glaucoma:
- have a family history of the condition
- have high intraocular pressure
- aged over 50
- are of African or Asian descent
- have diabetes
- are short or long sighted
- have been on a prolonged course of cortisone (steroid) medication
- experience migraines
- have had an eye operation or eye injury
- who have a history or high or low blood pressure
The majority of people will not experience symptoms in the early stages. It affects side (peripheral) vision before central vision. So this condition is known as the “silent thief of sight” because losing this part of your vision is not particularly noticeable in day to day life. Furthermore, you may think your peripheral vision is good, but it can actually be significantly deficient without you knowing. You simply cannot test it yourself.
Advanced testing equipment, including the Carl Zeiss Humphrey Field Analyser and the Carl Zeiss Cirrus HD-OCT are essential. Together, these instruments are essential in the comprehensive diagnosis and management of glaucoma.
Furthermore, guided progression analysis allows the optometrist to estimate your current stage of vision loss, measure changes over time and assess the rate of progression of your condition into the future. What this amounts to is better management in the long term.
So, diagnosis can be complex and requires a number of tests.
Screening should also be part of every eye health check. One screening test is commonly referred to as the “puff test” and involves a puff of air being blown onto the surface of the eye to check the internal eye pressure. It’s much like if you were to place your finger on the surface of a balloon to test it’s pressure. However, an instrument such as a Perkins Tonometer is recommended for more accurate measurements.
Treatment is very successful at stopping the progression of glaucoma. Many different types of treatment exist. They include oral medication, eye drops and a variety of surgical options. Generally, an ophthalmologist will initiate the treatments and perform any surgery. A suitably qualified optometrist with therapeutic endorsement can then co-manage the ongoing treatment over time.
Reducing your risk
Early diagnosis is essential. Therefore, a regular and complete eye health examination is the only way o reduce your risk of vision loss due to glaucoma.
Glaucoma damages the peripheral vision, resulting tunnel vision as in the above image.