Eye Examinations Explained

Even though most people are more frightened of losing their sight than any other sense, many do not go to their Optometrist for regular eye examinations. You should have an examination at least every two years, and not just to get a prescription for glasses.

An eye examination is done for several reasons:

  • To check how well you can see.
  • To give you a prescription for glasses that will correct any defects in your vision.
  • To check the health of the eye
  • To check general health

Your eye exam will be performed by an Optometrist – this is a person fully qualified to test eyes. The word Optometrist replaces the old title Ophthalmic Optician. Take the time to schedule in an examination on a regular basis with your Optometrist. Remember that unlike with the rest of your body, your eyes will not usually hurt if diseases are present. Glaucoma can lead to blindness if left untreated, yet you would not be aware of the symptoms until it was fairly well advanced.

In many optical practices support staff are trained to do pre-screening which the Optometrist uses as part of the test, or in some practices the Optometrist will do these tests himself. Often this comprises three tests, the first two of which are usually included in the cost of the standard examination:

1.Pressure Test

This is where a puff of air checks the internal pressure of the eyeball. It is used to detect signs of the eye disease glaucoma. This test feels a little strange but is not painful! Some practices may use equipment where you need eye drops before the pressure test. It is usually performed if you are over the age of 19.

2.Visual Field Test

This test checks how wide a field of view you have. This can detect signs of glaucoma, plus other diseases such as tumours. With modern equipment you look into a field screening machine and click a button to register that you have seen movements at different points around your visual field. The results are plotted out and the Optometrist will analyse them.

3.Digital Retinal Imaging

The third test is optional and you may have to pay separately for it;

This test takes a digital image of the inside of the back of the eye. This area is susceptible to several eye diseases which can lead to blindness if left untreated. The Optometrist does look at the back of your eye with an ophthalmoscope as part of the normal examination, but can only see a small amount of the retina at a time. The image can be stored, so potential problems can be re-assessed and compared at a later date.

4.The Eye Examination

Again this will differ slightly in every practice, but the Optometrist has guidelines from their Governing body which cover their obligation to you. The examination may also be tailored to your age, visual requirements, and any tests needed for professionals such as GPs or the DVLA.

Learning About You - The Optometrist needs to know about your lifestyle, any history of health problems, both your own and in your family. Your Optometrist also needs to know about your job and hobbies, and your personal visual requirements. They will also ask about any medication you may be taking or any medical treatment you are undergoing.

Refraction – This is the part of the test where your vision is assessed. It tells the Optometrist if you need glasses or contact lenses. Your vision is checked for reading, distance, and middle distance, which is for VDU work or for hobbies such as reading music. The Optometrist will use a special spectacle frame called a trial frame, into which he puts a series of test lenses, or a mechanised version called a phoropter. He will ask you what you see with a series of lenses, which checking and double checking several times over.

Retinoscopy – This is another way to check the prescription. The Optometrist uses a hand held light which can assess the amount of prescription you need. This can be used to check your responses, and is also useful when testing babies or people with learning difficulties as it does not require answers from the patient.

Pupil Reflex - the black centre of your eye gets bigger or smaller thanks to a variety of stimuli. Your Optometrist will check that your pupil reacts normally to light, as if it doesn’t it may be a sign of a neurological disease.

Muscle balance – The muscles that control your eye movements have to work together, to ensure that you don’t suffer from double vision. Your Optometrist will check that your eyes are co-ordinated and that your vision is comfortable.

Ophthalmoscopy – For this part of the test the Optometrist uses a hand held instrument to take a close look at the inside of the eye. It is of vital importance as it may detect eye health problems, and general health problems including diabetes, hypertension, and macular degeneration.

Checking your glasses – The Optometrist will check the glasses you presently wear to see if they are still suitable for your vision. He may have some useful suggestions as to new lenses which would be better suited to your visual requirements. He can also answer your questions about contact lenses or Laser surgery. Make sure you tell him if you are worried about any aspect of the test or your vision.

Your Prescription – The Optometrist will give you a copy of the prescription he has found, and you can use this to have your glasses made up at any outlet – other Opticians or here with us!