Understanding Glaucoma
Glaucoma is the name given to a group of eye conditions that can damage the optic nerve — the nerve that carries visual information from the eye to the brain.
The damage is usually associated with changes in the pressure inside the eye, although glaucoma can also develop when eye pressure is within the normal range.
Glaucoma often develops slowly and may not cause noticeable symptoms in its early stages. Regular eye examinations and appropriate monitoring are therefore important, particularly for people who have an increased risk of developing the condition.
How Does Glaucoma Affect Vision?
Glaucoma can gradually damage the optic nerve, affecting the way visual information is transmitted to the brain.
It commonly affects peripheral (side) vision first. Because this change is usually gradual, many people do not notice any difference in their sight during the early stages.
As the condition progresses, the field of vision can become increasingly restricted. Without appropriate treatment and monitoring, glaucoma can cause significant and permanent sight loss.
Damage caused by glaucoma cannot normally be reversed, but early detection and appropriate treatment can help slow or prevent further deterioration.
Who Is at Risk of Developing Glaucoma?
Glaucoma can affect people of any age, although it is more common as we get older.
Some factors can increase the likelihood of developing glaucoma, including:
- Age: The risk increases as we get older, particularly after the age of 40.
- Family history: Having a close relative with glaucoma increases your risk.
- Raised eye pressure: Higher than normal pressure inside the eye is an important risk factor.
- Ethnic background: Some forms of glaucoma are more common in people of African or Asian ancestry.
- Other eye conditions: Certain eye conditions, injuries or previous eye surgery can increase the risk.
Having one or more of these risk factors does not mean that you will necessarily develop glaucoma. Regular eye examinations help identify people who may need further assessment or monitoring.
How Is Glaucoma Detected and Monitored?
Glaucoma is usually detected through a combination of eye examinations and investigations. No single test can reliably identify every case, so eye-care professionals consider the results together.
Tests may include:
- Eye pressure measurement: Measures the pressure inside the eye.
- Visual field testing: Assesses peripheral vision and can identify areas where sensitivity may have been reduced.
- Optic nerve examination: Allows the appearance of the optic nerve to be assessed for changes associated with glaucoma.
- Optical Coherence Tomography (OCT): Uses light to produce detailed images of the structures at the back of the eye, helping identify changes in the optic nerve and surrounding nerve fibre layer.
Repeated assessments over time are often important because comparing results can help identify subtle changes and determine whether the condition is stable or progressing.
Can Glaucoma Be Treated?
Although damage caused by glaucoma cannot normally be reversed, treatment can help reduce the risk of further damage and preserve vision. The main aim of treatment is to lower the pressure inside the eye (intraocular pressure or IOP).
There are several treatment options, and the most appropriate approach depends on the type and severity of glaucoma, the level of eye pressure and the individual’s circumstances.
Selective Laser Trabeculoplasty (SLT)
SLT is a commonly used laser treatment for open-angle glaucoma and certain patients with ocular hypertension. It works by improving the drainage of fluid from the eye, helping to lower eye pressure.
NICE recommends offering SLT as an initial treatment for suitable patients with newly diagnosed, non-advanced chronic open-angle glaucoma. It can delay the need for daily eye drops, although additional treatment may be needed later.
Eye Drops
Prescription eye drops are used to lower eye pressure and remain an important treatment option. They may be recommended when SLT is not suitable, is declined, or does not lower the pressure sufficiently. Some patients require more than one type of eye drop to achieve adequate pressure control.
Eye drops need to be used regularly as prescribed.
Glaucoma Surgery
If laser treatment and eye drops do not provide sufficient control, or where the condition requires a different approach, surgery may be considered.
Surgical options include minimally invasive glaucoma surgery (MIGS), which may involve small implants or micro-stents to improve fluid drainage, as well as more established glaucoma operations such as trabeculectomy and drainage device surgery.
The most suitable treatment is determined by the glaucoma specialist, taking into account the patient’s individual needs and the risks and benefits of each option.
Why Is Regular Monitoring Important?
Glaucoma often progresses slowly, and changes to vision may not be noticeable until the condition is more advanced.
Regular monitoring allows changes in eye pressure, visual fields and the appearance of the optic nerve to be assessed over time.
This helps your eye-care team determine whether your condition remains stable or whether further investigation or treatment is needed.
It is important to attend all appointments arranged by your hospital eye clinic or community glaucoma service, even if your vision seems unchanged.
If you have been prescribed glaucoma eye drops, continue using them as directed unless your eye-care professional advises you otherwise.
Further Information
If you have been invited to attend our community glaucoma clinic, you can find out more about the service and what to expect from your appointment on the following pages:
- Community Glaucoma Services – learn about the North East Essex Community Glaucoma Service and the role of our clinic at Portland Medical Practice.
- Your Appointment – find out how appointments are arranged, what to bring and what happens during your visit.
If you have concerns about your glaucoma diagnosis or treatment, please discuss these with your hospital eye clinic glaucoma team.