Glaucoma is an eye condition where the optic nerve, which transmits visual information from the eyes to the brain, becomes damaged.
The most common reason is abnormally high pressure in your eye. This kind of pressure is known as intraocular pressure (IOP), and it's not connected to your blood pressure. The back of the eye constantly produces a fluid called aqueous humour that keeps your eyes healthy and at the correct pressure. It later leaves the eyes through channels in the cornea and the iris. However, if these channels are obstructed, the pressure in the eyes might increase and damage the optic nerve tissue. This damage is what's known as glaucoma.
Glaucoma can cause loss of vision, although this can be avoided if treated early.
Symptoms of Glaucoma
Glaucoma tends to affect the peripheral or side vision first, so most people with this condition don't notice any symptoms or experience any changes in their vision at the beginning. Very rarely, glaucoma can develop suddenly and cause:
- Intense eye pain
- Blurred vision
- Seeing halos around lights
- Redness in the eye
- Nausea and vomiting
In its early stages, however, it's usually only detected during an eye examination, so it's very important that you have regular eye tests. Without treatment, glaucoma can eventually lead to blindness.
(Vision in advanced stages of glaucoma)
Types of Glaucoma
Open-Angle Glaucoma: This is the most common type. It shows no symptoms except a gradual loss of vision. However, its development can be so slow that your eye can suffer great damage before it becomes apparent.
Angle-Closure Glaucoma: If the flow of the aqueous humour fluid is suddenly blocked, this can cause a quick and painful rise in eye pressure. You should immediately contact your doctor if you begin experiencing pain, nausea and a blurry vision.
Secondary Glaucoma: It appears as a result of another eye condition or an injury to the eye. Some types of medicines could also cause it. Rarely, it might be a side effect of eye surgery.
Normal Tension Glaucoma: Sometimes, the optical nerve of people with normal eye pressure may still get damaged. The cause isn't known, although it might be related to a lack of blood flow to your optic nerve or a greater sensitivity in the optic nerve.
Congenital or Childhood Glaucoma: Rarely, some children are born with an abnormality of the eye that prevents normal fluid flow and drainage, causing glaucoma. Symptoms might be cloudy eyes, an increased sensitivity to the light or excessive tearing.
- Age, the risk increases as we get older
- Genetics, some families have a history and are more likely to develop this condition
- Your ethnicity. People of African, Caribbean or Asian origin are at a higher risk
- Eye injury or other eye conditions, such as short-sightedness or long-sightedness
- Other medical conditions. People with diabetes or with high blood pressure and heart disease are at a greater risk
- Certain medicines. Taking steroids or corticosteroids for long periods of time might make you more likely to develop secondary glaucoma
Diagnose and Treatment
As we mentioned, optometrists can usually detect glaucoma during an eye examination. In this examination, the optometrist will perform vision tests and measure your eye pressure. If the test indicates that you have glaucoma, you should be referred to an ophthalmologist, who will explain the condition in detail and discuss available treatment.
Although no treatment can reverse vision loss caused by glaucoma, it can prevent the condition from getting worse. Depending on the type of glaucoma, your ophthalmologist might recommend:
- Eye drops
They can help reduce the pressure in your eyes. Most people won’t need any further treatment, but you may need to use them for life in order to avoid future damage to your sight.
- Laser treatment
If drops alone are not enough to control your eye pressure, laser treatment might be recommended. The most common type is called laser trabeculoplasty. The laser is applied to the trabecular mesh-work, which helps it work and drain fluid better to lower your eye pressure. It’s an easy procedure from which most people recover quickly.
In a small number of cases, where drops have not been successful or if the glaucoma is in an advanced state, surgery might be recommended. The most common kind of surgery is called a trabeculectomy, in which a new permanent drainage channel is created in your eye to help drain fluid and so lower eye pressure.
Low Vision Aids, Lighting and Technology
A number of tools and devices can help people with glaucoma carry out daily activities and maintain their independence. Low Vision Aids can be helpful for many daily tasks.
High quality sunglasses, such as the ones in our range, can help protect your eyes from damaging UV light. Their colour filters can also enhance contrast and improve object definition, helping you enjoy your time outdoors.