We are proud to offer a very comprehensive eye examination
We recommend you have an annual eye examination as part of preventative health care practice. It is important to detect and treat sight problems early in order to maintain good vision and eye health. Individuals may be unaware of problems because there are often no obvious signs or symptoms. Eye examinations will include some or all of the following:
Patient History: We will check the patient’s general health, medication, relevant eye history and any family incidence of glaucoma, diabetes etc.
Visual Acuity: This check enables us to evaluate how clearly each eye is seeing. Also known as the “Snellen Chart”, this tests distance and near vision. Normal distance visual acuity is 6/6 (in imperial measurement this is known as twenty-twenty) If you have 6/6 vision, you are seeing clearly at the appropriate distance. This is only an indication of visual clarity and other skills that contribute to overall vision.
Preliminary Tests: These help us to evaluate specific aspects of visual function and eye health.
Keratometry: This measures the curvature of the cornea, the clear outer surface of the eye. This is important for determining the “base curve” of the contact lenses.
Refraction: Refraction determines the appropriate lens power to compensate for near-sightedness, far-sightedness or astigmatism.
Binocular Vision: We use this to determine how well the eyes function individually and together, to assess the ability to focus (we call this 'accommodation') and eye movement ('ocular motility').
Eye Coordination: We check the ability of both eyes to work together. The brain fuses the images each eye sees in order to create one clear picture. Eye coordination is a developed skill and good coordination keeps the eyes in proper alignment. Poor eye coordination is often successfully treated with spectacles or eye exercises.
Eye Health Evaluation: We will examine the external parts of the eye, including the cornea, eyelids, conjunctiva and the surrounding eye tissue. In addition, the patient’s pupils may be dilated to evaluate the internal parts of the eye, including the lens, retina and the back of the eye ('posterior section').
Tonometry (the "air-puff" test): This test measures the pressure within the eye and helps in the detection of glaucoma. It is standard practice to test this in anyone over 40 or with a family history of glaucoma. A quick puffof air is used to flatten the cornea which allows the fluid pressure on the inside of your eye to be measured. Themachine will calculate your intra-ocular pressure on the basis of your eye's resistance to the air. It is completelypainless.
Visual Fields – These tests measure your field of view. You know how far down a letter chart you can read – that is a measure of your central visual ability but how well does the rest of your retina see? This test gives us this information. Field loss patterns can be useful diagnostic tools to identify specific diseases.
Supplemental Testing: We will carry out additional tests to confirm or rule out potential problems, and to provide clarification or further assessment.
Photography - Photographing the back of your eye is very useful in the monitoring of diabetic retinas. Other eye conditions such as retinal pigmentation can be documented this way.
Ocular Coherence Tomography (OCT) - The OCT enables us to see two and three dimensional views of the retina in cross-section. It can image and measure the optic nerve head and provide cross-sectional views of the cornea-iris interface. This enables us to more efficiently diagnose retinal diseases and glaucoma but more particularly perhaps, to monitor change over time i.e. between visits
Slit lamp examination - The slit lamp examination is rather like looking right into your eyes through a powerful microscope. In fact, the instrument used is called a biomicroscope and it allows your optometrist to get a close look at the external and internal structures of the eye. The eyelids, cornea, iris, conjunctiva, retina, optic nerve and macula are among the things that can be seen with a biomicroscope. Cataracts, macular degeneration, diabetic eye disease and corneal ulcers can all be detected by thorough examination.
Amsler grid testing - The Amsler grid is a pattern of lines in a square check formation, with a spot in the middle. While staring at the dot, you may notice variations in the regularity of the lines. This tests your central vision and can be used to detect age-related macular degeneration.
Dilation - The pupil (the black spot in the middle of your eye) is effectively the hole through which your optometrist looks into your eye. The larger the pupil, the bigger the "window" to look through. Because of this, you may be required to have some dilating drops put in your eyes if your pupils are particularly small or the optometrist wishes to have a better look at the back of the eye; these usually take about 20-30 minutes to start working and will probably make your eyes more sensitive to light, and your vision blurred. It is advisable to bring along a pair of sunglasses to your examination as this sensitivity can last for several hours after you have left the practice and you may need to arrange for someone drive you to home.
Colour Vision - The usual test for colour blindness involves looking at numbers formed from dots against a background of dots of a different colour. These pictures are called Ishihara plates. People with normal colour vision will see the number as it is meant to be, while people with colour vision problems may see a different number (for example a 3 instead of an 8), or perhaps no number at all.
These are the most common tests carried out in an eye examination, but there are others and you shouldn’t be alarmed if additional tests are performed on you that haven’t been mentioned here. It is also important that you’re honest in the answers you give to any questions the optometrist asks; concealing or even just playing down problems may make it more difficult to make a proper diagnosis.
Your Prescription
Refraction – Refraction is the optical correction of the refractive error of your eye. This may be plano (zero), or require positive or negative lenses, or a toric correction (see Optical Corrections) to obtain the clearest focus. It is used to determine the basis of your prescription.
Prescription - Your prescription should provide the most comfortable and practical solution to correct your eyesight. It is based on your refraction and in most cases will be the same. Occasionally it is slightly different for optical reasons and comfort.
In most cases a prescription for contact lenses is different from one for glasses. A prescription for contact lenses also covers the specification of your contact lenses (brand - power - base curve - diameter).
Conclusions
At the end of the examination the optometrist will discuss with you any eye health issues they may have found and talk to you about any additional testing or investigation that may be required. From here, they will let you know when you should have your next examination.
