Eye Exam General Information
How often should you have an eye examination
Everyone should have an eye test every two years, however if you experience an sudden change in your vision you should have an eye exam even if it has been less than 2 years since your last one.
Good reasons to get your eyes checked
- It has been 2 years since your last eye exam
- You are experiencing - headaches, nausea or dizziness after visual concentration
- blurred or double vision at any time
- crossed or turned eyes
- blinking or eye rubbing after visual concentration
- dislike or avoidance of close work
- short attention span
- placing head close to book when reading or writing
- frowning while looking at the TV or blackboard
- difficulty reading small print
- difficulty adjusting focus between near and far objects.
About Your Eye Examination
A routine vision examination in our office requires a total of approximately 30 minutes. This period of time is needed to perform all the tests necessary to thoroughly asses your eyes and visual efficiency.
During your examination a health history will be taken. It is important for you to provide all information, regardless of how insignificant you might think it is.
Tests related to the following are all part of a complete examination:
- Eye health - Ophthalmoscopy - examine the retina and the inside of the eyeball
Tonometry - Checking the eye pressure
Slit lamp biomicroscopy - examine the outside surface of the eye.
- General physical health
- Clearness of vision ( Myopia , Hyperopia , Astigmatism )
- Colour vision
- Focusing ability ( Presbyopia)
- Eye muscle control
- Amblyopia (lazy eye)
- Cataract and other appropriate areas for each individual.
Following the examination, we will carefully explain the results of your testing and discuss our recommendations regarding any needed preventive or remedial care.
During Your Eye Examination
An eye examination is a routine and pleasant experience. Some advice...
- Don't worry about making a mistake or giving the wrong answer
- Don't worry about your answers contradicting one another
- Don't hesitate to say so if you are unable to answer some of the questions
- Don't be alarmed if, for a few minutes during the examination, you find your vision getting worse instead of better.
How to prepare for an eye exam
If you're seeing a new eye doctor or if you're having your first eye exam, expect questions about your vision history. Your answers to these questions help your eye doctor understand your risk of eye disease and vision problems. Be prepared to give specific information, including:
- Are you having any eye problems now?
- Have you had any eye problems in the past?
- Do you wear glasses or contacts now? If so, are you satisfied with them?
- What health problems have you had in recent years?
- Are you taking any medications?
- Do you have any allergies to medications, food or other substances?
- Has anyone in your family had eye problems, such as cataracts or glaucoma?
- Has anyone in your family had diabetes, high blood pressure, heart disease or any other health problems that can affect the whole body?
If you wear contact lenses, bring them to your appointment. Your eye doctor will want to make sure your prescription is the best one for you. Also be prepared to remove your contacts for certain exams. Tests that use orange dye (fluorescein) to temporarily colour your eye may permanently dye your contact lenses. You'll want to take them out before those types of tests.
Eye exams involve more than testing your vision - and, if you need glasses or contacts, determining how strong your correction should be. Additional tests assess the appearance and function of all parts of your eyes.
Visual field test (perimetry)
Your visual field is the area in front of you that you can see without moving your eyes. The visual field test determines whether you have difficulty seeing in any areas of your peripheral vision - the areas on the side of your visual field. There are a few different types of visual field tests:
- Confrontation visual field exam. Your eye doctor sits directly in front of you and asks you to cover one eye. You look directly at your eye doctor while he or she moves his or her hand in and out of your visual field. You tell your doctor when you can see his or her hand.
- Tangent screen exam. You sit a short distance from a screen and stare at a target at its centre. You tell your doctor when you can see an object move into your peripheral vision.
- Automated perimetry. Your eye doctor uses a computer program that flashes small lights as you look into a special instrument. You press a button when you see the lights.
Using your responses to one or more of these tests, your eye doctor makes a map of your peripheral vision. If you aren't able to see in certain areas, your eye doctor uses the map to help diagnose your eye condition.
A slit lamp is a microscope that enlarges and illuminates the front of your eye with an intense line of light. Your doctor uses this light to examine the cornea, iris, lens and anterior chamber of your eye.
When examining your cornea, your doctor may use eye drops containing fluorescein (flooh-RES-ene) dye. The orange dye spreads across your eyes to help your eye doctor detect tiny cuts, scrapes, tears, foreign objects or infections on your cornea. Your eyes' tears will wash the dye away.
Retinal examination (ophthalmoscopy)
A retinal examination - sometimes called ophthalmoscopy or fundoscopy - examines the back of your eye, including your retina, optic disk and the underlying layer of blood vessels that nourish the retina (choroid). Usually before your doctor can see these structures, your pupils must be dilated with special eye drops. The eye drops may sting briefly and might cause a medicinal taste in your mouth as the medication drains from your tear ducts into your throat.
After administering eye drops, your eye doctor may use one or more of these techniques to view the back of your eye:
- Direct examination. Your eye doctor shines a beam of light through your pupil and uses an ophthalmoscope to see the back of your eye. Sometimes eye drops aren't necessary to dilate your eyes before this exam. You might see afterimages when your eye doctor stops shining the light in your eyes. This is normal and will go away.
- Indirect examination. For this exam you might lie down or recline in a chair. Your eye doctor will hold each eye open and examine it with a bright light mounted on his or her forehead - a bit like a miner's lamp. This exam lets your eye doctor see your eye in great detail and in three dimensions. Since this light is brighter than that in a direct examination, you are more likely to see afterimages, but they disappear quickly.
- Slit-lamp exam. In this exam your doctor uses the slit lamp along with the ophthalmoscope to look at the back of your eye. The slit lamp reveals more detailed views of the back of your eye than do direct or indirect examinations.
The retinal examination takes five to 10 minutes, but if you're given eye drops, their effects won't wear off for several hours. Your vision will be blurry, and you'll have trouble focusing your eyes. You may not be able to drive, so make sure you have another way back to work or home. Depending on your job, you might not be able to work until the eye drops wear off.
Glaucoma test (tonometry)
Tonometry measures your intraocular pressure - the pressure inside your eyes. It helps your eye doctor detect glaucoma, a disease that causes pressure to build up inside your eyes and can cause blindness. Glaucoma can be treated if it's caught early.
Methods your eye doctor may use to test your eyes for glaucoma include:
- Applanation tonometry. This test measures the amount of force needed to temporarily flatten a part of your cornea. Fluorescein, the same orange dye used in a regular slit-lamp exam, is usually put in your eye to make your cornea easier to see. You'll also receive eye drops containing an anaesthetic. Using the slit lamp, your doctor moves the tonometer to touch your cornea. It won't hurt, and the anaesthetic will wear off within two hours.
- Noncontact tonometry. This method uses a puff of air to test the pressure in your eye. No instruments will touch your eye, so you won't need an anaesthetic. You'll feel mild pressure on your eye, which can be uncomfortable, but it lasts only seconds.
- Pachymetry. This test measures the thickness of your cornea - an important factor in evaluating your intraocular pressure measurement. After applying numbing eye drops, your eye doctor uses an instrument that emits ultrasound waves to measure your corneal thickness.
Besides these basic evaluations, you may need more specialized tests, depending on your age, medical history and risk of developing eye disease.