Glaucoma

Glaucoma is a group of eye conditions in which the optic nerve is gradually damaged. In most cases, this is caused by excessive pressure within the eye, also known as intraocular pressure. The fluid in your eye (aqueous humour) is normally produced and drained in a natural balance. In glaucoma, this balance is disrupted, causing the pressure to rise and putting the optic nerve under strain.

The optic nerve connects your eye to your brain and is responsible for transmitting visual information. Damage to this nerve is irreversible and leads to permanent loss of visual field. Glaucoma often develops slowly and without obvious symptoms in the early stages, meaning that many people only notice it once damage has already occurred.

Types of glaucoma

There are various forms of glaucoma, the two main ones being:

• Open-angle glaucoma: the most common form, in which the drainage of aqueous humour gradually becomes less effective. This type usually develops gradually and without pain.
• Closed-angle glaucoma: a less common but more acute form, in which the drainage system becomes suddenly blocked. This can lead to a rapid rise in pressure and acute symptoms such as pain, blurred vision and nausea.

In addition, there is normal-tension glaucoma, in which the optic nerve is damaged despite normal eye pressure, and congenital glaucoma in babies and young children.

Causes and risk factors

The exact cause of glaucoma is not always clear, but a number of factors increase the risk:

• Elevated eye pressure
• People aged over 40
• Glaucoma in the family
• Ethnic background (people of African or Asian descent are at increased risk)
• Severe short-sightedness or long-sightedness
• Long-term use of corticosteroids
• Previous eye injuries or infections

Glaucoma cannot be reversed, but early detection and treatment by an ophthalmologist can slow down further deterioration.

Recognition and monitoring

As glaucoma often causes no symptoms in its early stages, regular eye check-ups are important, especially if you are at increased risk. Your optician or optometrist can measure your eye pressure and assess your optic nerve during an eye test. If glaucoma is suspected, you will be referred to an ophthalmologist for a comprehensive examination, including visual field tests and imaging of the optic nerve.

Contact lenses and glaucoma

If you have glaucoma, in many cases you can continue to wear contact lenses as normal. However, it is important that you discuss this with your ophthalmologist or optician. Some eye drops prescribed for glaucoma may affect your tear film or lens comfort. Furthermore, certain types of lenses or wearing schedules may be more suitable for your situation.

Make sure you always use contact lenses and lens solution in accordance with the instructions for use and that you continue to book regular check-ups. As far as is known, wearing contact lenses does not affect glaucoma. However, good eye hygiene and regular check-ups remain important.

When to see an optician

Do you have symptoms such as gradual loss of peripheral vision, blurred vision, halos around lights, sudden eye pain or headaches, or are you concerned about your eye pressure? If so, have it assessed by your optician, optometrist or ophthalmologist. Early detection makes a big difference to the progression of glaucoma.