What is an Eye Examination?
An eye examination is a range of tests performed to assess eye health and function. The tests can be as simple as reading letters from a standard eye chart, or can involve special instruments that examine the structures inside the eye in detail.
Regular eye examinations are very important to ensure the health and overall wellness of your eyes.
They can be performed to:
- Determine the prescription for glasses or contact lenses, for short-sightedness (myopia), long-sightedness (hyperopia) and other focusing problems
- Detect common and chronic eye diseases, such as glaucoma, cataracts, age-related macular degeneration (AMD) and diabetic retinopathy
- Spot early signs of eye disease, when treatment is most effective, which also helps in the assessment of treatment methods
- Pick up signs of other health conditions that can affect the eyes, such as diabetes and high blood pressure
When Should You Have an Eye Examination?
You should get an eye examination done if you:
- Have difficulties with your vision, such as blurred vision, trouble seeing at night, or needing to squint to see clearly
- Have recurrent headaches or eye strain, especially after reading or using screens
- Have red, itchy or watery eyes that do not settle
- Have noticed flashes of light or floaters (spots or strands drifting across your vision)
- Have recently experienced head trauma or an eye injury
- Are due for a routine check, even if you have no symptoms
You may need more frequent eye examinations if you have a family history of eye disease, or conditions like diabetes. Diabetes can damage the blood vessels in the eye, and a family history of conditions can raise your risk of eye diseases such as age-related macular degeneration (AMD) and glaucoma.
Others who may need closer monitoring include people with high short-sightedness, people aged 40 and above, people with high blood pressure, and people who take steroid medication for a long period.
Please seek medical help immediately, and do not wait for a routine appointment, if you have sudden loss or blurring of vision, a sudden shower of floaters or flashes of light, a dark curtain or shadow across your vision, severe eye pain, a red eye with pain and blurred vision, or an eye injury or chemical splash.
Why this matters in Singapore
Singapore has one of the highest rates of short-sightedness in the world. Around 65% of children here need glasses by the age of 12, and about 4 in 5 young adults are myopic. High myopia increases the risk of eye problems later in life, including glaucoma, early cataracts and macular degeneration. Children in Singapore are screened for vision problems annually under the National Myopia Prevention Programme, and parents are encouraged to have their children’s eyes checked if they notice squinting, sitting too close to the television or frequent headaches.
In adults, the main causes of vision loss in Singapore include cataracts, uncorrected refractive error, diabetic retinopathy, age-related macular degeneration and glaucoma, according to the Ministry of Health. About 1 in 11 residents aged 18 to 74 has diabetes, and diabetic retinopathy is projected to more than double between 2015 and 2040 as the population ages and diabetes becomes more common. Annual eye screening is recommended for people with diabetes.
Many serious eye diseases, such as glaucoma and diabetic retinopathy, cause no symptoms in their early stages, and by the time vision is affected, some damage may already be permanent. Glaucoma is being found in people in their 40s and 50s here, and angle-closure glaucoma is more common among Chinese Singaporeans. This is why a regular eye examination matters even if you feel that your eyesight is fine. Your doctor can advise how often you should be checked, usually every one to two years for adults, and more often if you have risk factors.
What Happens Before an Eye Examination?
You will be asked about your medical history and any symptoms of vision problems that you have noticed. To help your doctor, it helps to:
- Bring your current glasses or contact lenses, and your previous prescription if you have one
- Wear your glasses rather than contact lenses if possible. If you wear contact lenses, you may be asked to remove them before some of the tests. Please ask when you make your appointment how long before the examination you should stop wearing them
- Bring a list of your medications, including eye drops, and details of any health conditions such as diabetes or high blood pressure
- Tell your doctor about your family history of eye conditions, such as glaucoma or macular degeneration
- Tell your doctor about any allergies, especially to eye drops or medication
- Note down any symptoms, including when they started and whether they affect one eye or both
- Bring a pair of sunglasses, and arrange for someone to accompany you, as your vision may be blurred after having your pupils dilated
- Bring your NRIC (or passport if you are an international patient), and your doctor’s referral letter if you have one
What Happens During an Eye Examination?
Several tests are done to evaluate a range of eye problems and disorders. Your examination may include some or all of the following, depending on your needs.
Vision and colour tests
- You may be asked to read letters of different sizes on a chart, to test for long- or short-sightedness and other focusing problems. Lenses may be placed in front of your eyes to find the prescription that gives you the clearest vision.
- You may also be asked to look at colours printed on a chart to check for vision clarity. This test can also detect colour deficiency, or whether you are colour blind.
Examining the front of the eye
- Your inner eye structure and the back of your eye may be examined for damaged cells.
- Fluorescein dye may be used to detect foreign bodies or injuries to the cornea, the clear surface that covers the front of the eye. The dye is applied to the surface of the eye, and spreads over the eye when you blink.
- A cobalt-blue light is then directed onto your eye through an instrument called a slit lamp, which is like a microscope with a bright light. Any abnormalities, abrasions or damage to the cornea show up clearly under the light.
Measuring eye pressure
- Your eye pressure may be measured to detect glaucoma, a condition in which the optic nerve is damaged. The test is done with a machine or through a slit-lamp tonometer.
- Numbing (anaesthetic) eye drops are used for some methods of measuring eye pressure, so that you do not feel the instrument touch your eye.
- If your eye pressure is higher than normal, your corneal thickness may also be assessed, using an instrument that uses sound waves to measure the thickness of the cornea. Corneal thickness can affect pressure readings.
Examining the back of the eye
- A retinal examination assesses the structures at the back of the eye, including the retina and optic nerve, to check for possible eye disease.
- Dilating drops may be used to widen your pupils so that the doctor can see the back of your eye more clearly. They take about 15 to 30 minutes to work.
- Further tests, such as retinal photographs or scans, may be recommended if the doctor needs a closer look.
What Happens After an Eye Examination?
- If you had your pupils dilated, your vision may be blurry and you may be sensitive to light for several hours. Wear sunglasses, and do not drive until your vision has returned to normal. It is a good idea to have someone take you home.
- Your eyes may feel slightly stingy or watery for a short while after the drops. Avoid rubbing your eyes.
- Your doctor will discuss the findings with you, and will tell you if you need glasses, treatment or more tests.
- You will be given a follow-up appointment to review your test results.
Understanding Your Results
- A new or updated prescription. If you need glasses or contact lenses, or a change in prescription, you will be given a prescription that you can take to your optician.
- Normal findings. Your eyes show no signs of disease. Your doctor will advise when your next examination is due.
- Signs of eye disease. If early signs of conditions such as glaucoma, cataract, macular degeneration or diabetic retinopathy are found, your doctor will explain what they mean and recommend monitoring, eye drops, laser or other treatment. Treatment is usually most effective when started early.
- Signs of other conditions. An eye examination can sometimes show signs of conditions such as diabetes or high blood pressure, and your doctor may advise tests or a visit to your family doctor.
Looking After Your Eyes
- Have regular eye examinations, and more often if you have diabetes, high myopia, a family history of eye disease or are aged 40 and above
- Keep your blood sugar and blood pressure well controlled, as high levels can damage the blood vessels in the eyes
- Give your eyes regular breaks from screens. Try the 20-20-20 rule: every 20 minutes, look at something 20 feet (about 6 metres) away for 20 seconds
- Encourage children to spend time outdoors every day, as this may help to slow the progression of myopia
- Wear sunglasses that block ultraviolet (UV) light when outdoors, and wear protective eyewear for sports and DIY
- Do not smoke, as smoking increases the risk of cataracts and macular degeneration
- Eat a balanced diet that includes leafy green vegetables, fruit and fish
- Keep contact lenses clean, do not sleep in them unless advised, and avoid rubbing your eyes
Should you experience vision difficulties or red or itchy eyes, contact your doctor immediately or call our 24-Hour Medical Urgency Clinic.
