Glaucoma testing: why there’s nothing to fear

Worrying about an eye test can be stressful, especially if you’re feeling any kind of eye discomfort. Whether it’s thinking about what the optometrist will say, or if you’ve convinced yourself you’ve got some form of rare eye disease because “that’s what the internet says”, the build-up can be stressful. It’s the same for any medical situation. You fear the worst.

Glaucoma is a group of eye conditions that cause damage to the optic nerve. It is a serious eye condition, but advancements in eye exam technology now mean we can detect it in your routine eye test.

We understand how troubling it can be to think you may have a condition such as glaucoma — no matter your age.

To alleviate some of these worries, we’ve interviewed one of our clinical experts, Hayley Moore BSc (Hons) MCOptom, about the Specsavers eye test routine.

“What can people expect from a Specsavers eye exam?Should they be concerned about glaucoma?”

All Specsavers eye tests are quick, painless and include checking for signs of glaucoma, including an examination of the back of the eye (retina) which is carried out on all our customers. This can be done in a variety of ways.

Ophthalmoscope

This is an instrument with lights and a series of magnifying lenses which is brought close to the eye to assess the retina. The optometrist will pay particular attention to the optic nerve as this is where glaucoma presents itself. The ophthalmoscope also allows an assessment of the overall eye health.

Digital retinal photography

As standard, we use digital retinal photography in every eye test when possible. This takes a picture of the retina for the optometrist to evaluate.

This photograph would typically be taken by an optical assistant in the ‘pre-test’ before your full eye examination and involves using a specialist camera. You’ll find it’s the same as having a normal photo taken with the flash on.

Examining the retina in 3D

As the optic nerve is not flat, but has height and depth, being able to use equipment that can assess the optic nerve in 3D gives the optometrist more ability to evaluate its health.

We use several methods for examining the retina in 3D. Commonly, the optometrist will use a microscope known as a slit lamp. This is where you rest your chin on the instrument as the optometrist uses a slit of light to examine the structures of the eye.

The optometrist then uses a small but powerful lens held in front of the slit lamp to view the retina in 3D. You’ll only be aware of a bright light.

Optical Coherence Tomography

Select Specsavers stores now use advanced scanning equipment known as Optical Coherence Tomography (OCT). This allows optometrists to view the entire central retina and optic nerve in 3D, evaluating all of the deeper layers of the retina and providing us with a comprehensive level of information about the health of the eye.

Each OCT scan takes around a minute and involves you keeping your chin rested on the scanning machine while a series of lights are directed at the surface of the eye. It’s completely harmless, painless, simple and is state-of-the-art technology for detecting glaucoma. You can learn more about exactly how it does this here.

There are several methods for measuring eye pressure. The most simple is using an instrument called a Non-Contact Tonometer, most people know this as the ‘puff-of-air’ test during pre-test stage. Again, this is completely painless and is a very simple test to undergo.

If the eye pressure measured with the air puff is higher than expected, or other risk factors for glaucoma are present, the optometrist may measure the eye pressure using a more complex system. This can involve eye drops and an instrument which makes gentle contact with the front surface of the eye (typically a Goldmann or Perkins Tonometer). This gives a more accurate result if the pressure is suspected to be abnormal with the air puff method. You may feel slight discomfort in this instance due to eye contact, but it’s only slight.

Visual field testing

As part of the assessment for glaucoma, as well as other eye conditions, an optometrist may request a visual field test. The instrument used evaluates the peripheral vision in each eye. This test is usually carried out by a qualified optical assistant.

You’ll either have to press a button when you see a light flashing, or count the number of flashing lights you see, depending on the type of visual field machine used.

“What questions can people expect to be asked by Specsavers eye care professionals?”

An optometrist would want to find out whether you have any specific risk factors for developing glaucoma, and so would ask questions about:

Ethnicity: in certain ethnic groups, such as Afro-Caribbean, the risk of glaucoma is higher.

Family history: there is an increased risk if someone in your immediate family has glaucoma — parents, siblings, and children.

Age: over the age of 40, the risk of glaucoma increases with every decade..

People who have thinner corneas: you may only know this if you have been seen in a hospital eye department before. Learn more about the link between corneas and glaucoma here.

History of short-sightedness (myopia): there is an increased risk of glaucoma if you have a -6.00D lens prescription.

General health: there is an increased risk for glaucoma if you have diabetes or high blood pressure, for example.

Medication: taking topical or systemic steroids may lead to steroid-induced glaucoma.

“What questions should customers ask if they’re feeling apprehensive about an eye test?”

You may have many questions before, during, and after an eye test — and all are understandable and relevant. Don’t be afraid to ask your optometrist anything. Here are some example questions and answers.

“How long does the test take?”

The whole examination takes around 30 minutes and the individual tests are generally quick and painless.

“I’m worried I might have symptoms of other eye conditions”

Specsavers eye tests conduct a comprehensive health assessment not just for glaucoma but other sight-threatening conditions which you may be completely unaware of.

“Will I get confused during the test and give wrong answers?”

Many people worry they will give the ‘wrong answer’ and end up with glasses when they don’t need them, or wearing the incorrect prescription. This is not possible as optometrists use a variety of methods to test the eyes — including examinations where no response from the customer is necessary.

We can also accurately test the eyes of children before they can speak or read, and people who have dementia, who are non-verbal or who don’t speak English – so there is no chance of ‘getting it wrong’.

“I’m worried about glaucoma. When should I see an optometrist?”

Early detection is key: as many as 50% of cases are undiagnosed. This statistic is worrying because most people who are diagnosed early will retain useful sight for life. However, if left unchecked and untreated, glaucoma can lead to complete sight loss.

“Why should I come to Specsavers?”

We offer a full assessment of eye health and vision; this is a legal requirement in UK eye testing. On top of this, every store in the UK now has optometrists who have undertaken additional post-graduate accreditations in glaucoma. For example, we have almost 2,000 optometrists with the higher-level of post-graduate glaucoma accreditation, and almost 2,500 optometrists with a higher-level qualification in minor eye conditions accreditation. So you’re in good hands.

“What are the chances of misdiagnosis?”

We would not diagnose glaucoma, only detect possible signs which would warrant referral for specialist investigation. This means that if signs are present, you would be referred to an ophthalmologist: a specialist eye doctor. If you’re concerned about misdiagnosis, you can learn more about what to ask your ophthalmologist here.

Eye tests can be confusing and worrying, especially if you think you’re symptomatic of something. We’re here to alleviate those fears.

For more information relating to glaucoma, please visit our dedicated learning resource. You can also book an appointment with your local Specsavers here.

Hayley Moore
MOptom (Hons) MCOptom Dip Tp(IP) Prof Cert Glau Prof Cert Med Ret

Hayley is an optometrist and prior to joining Specsavers in 2016 has worked in a variety of settings, including hospital and independent practice. Most notably, Hayley was National Optometry Development Manager for Ultralase, and is a refractive surgery and intra-ocular lens specialist. Read more