If you’re younger than 40 and have no eye problems, your doctor might suggest you get routine tests every 2 years. Or he could tell you that you don’t need any tests. Ask what he thinks is best for you.
If you’re 40 or older, you should get your eyes checked every 1 to 2 years.
If you’ve had eye trouble in the past, or if you’re at risk for developing it (if someone in your family had it), you should see an eye doctor every year.
Why? You need to check to see if you have serious, sometimes “silent” problems that can affect your vision, like:
- Age-related macular degeneration
- Diabetic retinopathy
Are My Eyes at Risk?
If you have a health condition like high blood pressure, work in a job that requires you to use your eyes a lot, or take drugs that can affect eyesight, you may need more frequent exams.
If you have type 1 diabetes, get your eyes checked within 5 years of your diagnosis and every year after that.
You’ll need an exam ASAP if you’re diagnosed with type 2 diabetes. Have your eyes checked every year after that.
How to Prepare
When you call to make an appointment for your exam, mention any vision problem you’re having.
Before you go, list any questions you want to ask the doctor. Also be ready to update him or her on any medicines you take and your (and your family’s) eye health history.
Bring your glasses and contact lenses along with the prescription with you. Also bring sunglasses for the trip home. The doctor might use eye drops to open up your pupils. This is called dilation. Your eyes will be sensitive to light afterward.
During Your Eye Exam
First, the eye doctor or an office staff member will ask you about your medical and vision history.
The exam may last from half an hour to several hours, depending on the equipment used. It will cover your vision and your eye health.
You’ll probably have all or most of the following eye tests, and possibly some other ones, too:
Eye muscle movement test: This checks your eyes’ alignment. The doctor will watch your eyes move while you follow a target (like a finger tip or his pen) as it moves in different directions.
Cover test: This tells how well your eyes work together. You’ll stare at a small target some distance away. The doctor will cover and uncover each eye to observe how much your eyes move. Your doctor will also be watching for an eye that turns away from the target. This is a condition called strabismus. You may take the test again with a target close to you.
External exam and pupil reactions: The doctor will watch how your pupils adjust to light and objects close to you. At the same time, the whites of your eyes and the position of your eyelids will also be checked.
Visual acuity test: You’ll sit in front of an eye chart, with letters that get smaller as you read down each line. You’ll cover each eye in turn and, using the other eye, read aloud, going down the chart, until you can’t read the letters anymore.
Refraction testing: For your exact lens prescription, the doctor can use a computerized refractor. Your doctor may fine-tune the prescription by flipping the phoropter back and forth between lenses and asking you which is better. If you don’t need corrective lenses, you won’t have this test.
Slit lamp (biomicroscope): This device magnifies and lights up the front of your eye. The doctor uses it to check your cornea, iris, lens, and the back of your eye, looking for signs of certain eye conditions.
Retinal examination ( ophthalmoscopy ): Your doctor may dilate your pupils and use a tool called an ophthalmoscope and to see the back of your eyes — the retina, retinal blood vessels, fluid in your eyes (he may call this vitreous fluid), and the head of your optic nerve.
Glaucoma testing: This procedure checks to see if the fluid pressure inside your eyes is within a normal range. It’s fast, painless, and can be done in a couple of ways:
- Tonometer: This is the most accurate. You’ll get drops to numb your eyes. The doctor will tell you to stare straight ahead and will barely touch the front surface of each eye with a tool called an applanation tonometer or Tonopen to measure the pressure.
- Puff of air or noncontact tonometer: You’ll stare at a target, and a machine will let out a small puff of air into each eye. How much your eye resists the puff indicates the pressure inside it.
Pachymetry: This test uses ultrasound to measure the thickness of your cornea. Thin corneas can lead to false low-pressure readings. Thick corneas can lead to false high-pressure readings. You’ll get this test just once to create a baseline for comparison with future readings. It can be used for people who need corneal surgery.
Pupil dilation (enlargement): With your pupils fully enlarged, the doctor will use tools and lights to check the insides of your eyes. The eye drops for this part of the exam take about 20-30 minutes to work. They make your eyes more sensitive to light and blur your vision. These effects may last for several hours or longer. This is why you might need those sunglasses on your way home. Newer machine can look in the far back of your retina without your pupils being dilated.
Visual field test (perimetry): Your visual field is the area you can see in front of you without moving your eyes. Using one of three tests, the eye doctor maps what you see at the edges (periphery) of your visual field and will use this map to diagnose eye conditions.