Glaucoma Up-Close

Untreated, glaucoma can cause blindness.

The onset of glaucoma can be a gradual one. So much so, that a significant amount of side vision will be lost before the individual has even noticed they have a condition.

(Glaucoma Australia 2019; Vision Eye Institute 2019; Healthdirect 2017)

What is Glaucoma?

Glaucoma is the name given to a range of conditions that lead to optic nerve damage. This is the nerve that transmits signals from the eye to the brain to create the image we see.

If a considerable number of nerve fibres are affected, the peripheral field of vision is lost – this loss slowly creeps toward the central vision. Currently, glaucoma cannot be reversed.

People who have experienced glaucoma report feeling: frightened; confused; alarmed; and being in discomfort in the onset of the condition. (Glaucoma Australia 2019)

Variants of Glaucoma

Primary Open-Angle Glaucoma

In the case of primary open-angle glaucoma, a patient loses their peripheral vision due to the optic nerve becoming damaged. Insufficient drainage of fluid from the eye is responsible for pressure and nerve damage.

This type of glaucoma typically does not cause pain and is therefore difficult to detect. As with other types of glaucoma, the early signs may be very subtle.

How Common is it?

This is the most common type of glaucoma – it is responsible for around 90% of reported glaucoma cases in Australia. (Glaucoma Australia 2019)

Normal Tension Glaucoma

Normal tension glaucoma is the term given to cases in which the patient has ‘normal’ eye pressure and therefore other reasons must be considered in determining changes in nerve pressure and visual field loss.

How Common is it?

Normal tension glaucoma accounts for roughly one-third of glaucoma cases in Australia. (Glaucoma Australia 2019)

Chronic Angle-Closure Glaucoma

Chronic angle-closure glaucoma is a result of an inherited narrowness of the drainage angle of the eye. Aqueous fluid must drain through the angle between the trabecular meshwork and the iris and in this condition, it is unable to.

People with chronic angle-closure glaucoma may be prone to experiencing an acute attack.

How Common is it?

Chronic angle-closure is more common in people who are long-sighted, older people, female and of Asian background. (Glaucoma Australia 2019)

Acute Angle-Closure Glaucoma

When there is a very sudden increase in pressure within the eye as a result of the iris blocking the drain through which fluid leaves the eye, this is considered as acute angle-closure glaucoma. Immediate medical attention is required as this can lead to permanent sight-loss.

Symptoms may include pain, nausea, blurred vision and redness of the eye.

How Common is it?

Acute angle-closure is also mostly experienced by people who are long-sighted, older people, female and of Asian background. (Glaucoma Australia 2019)

Childhood Glaucoma

An abnormal drainage system is responsible for childhood glaucoma. It can be detected by noticing that children are particularly sensitive to light and have excessively cloudy and watery eyes.

How Common is it?

Childhood glaucoma is rare and devastating when it does occur. Cases tend to range in their severity. (Glaucoma Australia 2019)

Who is at Risk?

Those with a family history of glaucoma are at the greatest risk of developing this condition.

Other main predictors include:

• Age;
• Short-sightedness;
• Diabetes mellitus;
• Migraines;
• A grave injury to the eye;
• The use of steroids regularly over a long time period; and
• Hypertension.

Those in high-risk categories should have their eyes examined well before the age of 35. (Vision Australia 2019; Healthdirect 2017)

Glaucoma Statistics

An estimated 300,000 Australians are currently living with glaucoma. Furthermore half of those people have not been diagnosed. It occurs in one in ten people over the age of 80.

Having a first-degree relative who has glaucoma increases the risk of developing glaucoma eight-fold. (Cera 2018)

Glaucoma Diagnosis

If a doctor or optometrist suspects that a person may have glaucoma, they may be referred to an ophthalmologist for further investigation and analysis. A range of eye tests will then be taken in order to confirm the diagnosis. (Vision Eye Institute 2019)

Symptoms of Glaucoma

Symptoms most often associated with glaucoma include:

• Painless and blurred vision;
• Loss of peripheral vision; and
• Trouble adjusting to low light.
(Vision Australia 2019)

Glaucoma Treatment

Treatment is available that is designed to prevent or delay further damage, primarily by reducing the pressure in the eye.

Typically, this involves:

• Eye drops or medicine;
• Laser surgery or other surgery to open or create a new drainage channel.
(Healthdirect 2017)

Preventative Measures

The most effective way to ensure glaucoma prevention is to have regular eye tests – early diagnosis and treatment is essential. (National Eye Institute 2015)

Additional Resources

To gain a better understanding of glaucoma, Glaucoma Australia has curated a list of several stories from the perspectives of people living with the condition: https://www.glaucoma.org.au/about-glaucoma/glaucoma-stories/

References

• Centre For Eye Research 2014, ‘Glaucoma’, viewed 25 June 2019, https://www.cera.org.au/community/your-eye-health/glaucoma/
• Glaucoma Australia 2019, ‘My Story: My Glaucoma’, viewed 25 June 2019, https://www.glaucoma.org.au/about-glaucoma/glaucoma-stories/
• Glaucoma Australia 2019, ‘What is Glaucoma?’, viewed 24 June 2019, https://www.glaucoma.org.au/about-glaucoma/what-is-glaucoma/
• National Eye Institute 2015, ‘Facts About Glaucoma’, viewed 25 June 2019, https://nei.nih.gov/health/glaucoma/glaucoma_facts
• Healthdirect 2017, ‘Glaucoma’, viewed 24 June 2019, https://www.healthdirect.gov.au/glaucoma
• Vision Australia 2019, ‘Glaucoma’, viewed 25 June 2019, https://www.visionaustralia.org/information/eye-conditions/glaucoma
• Vision Eye Institute 2019, ‘Glaucoma’, viewed 25 June 2019, https://visioneyeinstitute.com.au/services/glaucoma/

(Answers: b, a, b.)