Eye Conditions and FAQ
Click one of the following topics to jump to its entry on this page:
- Symptoms of Vision Problems
- Dry Eye Syndrome
- Myopia (Short-sightedness)
- Hyperopia (Long-sightedness)
- Macular Degeneration
- Amblyopia (Lazy Eye)
- Eye Muscle Inco-ordinations
- Spots and Floaters
- Laser Surgery
- Colour Vision and Colour Blindness
- What is “Normal” in my vision?
- How Often Should I Have My Eyes Examined?
Symptoms of Vision Problems
Following is a partial list of symptoms in children and adults which indicate the need for a complete vision analysis:
- 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.
Dry Eye Syndrome
Dry eye syndrome is a chronic lack of sufficient lubrication and moisture in the eye. This is caused when the eye doesn’t get enough tears, or the tears have a chemical composition which causes them to evaporate too quickly.
Symptoms can include persistent dryness, scratching and burning in your eyes and the feeling that something is in your eye.
Dry eye syndrome has many causes. It occurs as a natural part of the aging process, especially during menopause; as a side effect of many medications, such as antihistamines, anti-depressants and birth control pills; or environmental factors.
Dry eye syndrome is an ongoing condition that may not be completely curable (depending on the cause), but the symptoms can be managed. Lubricating eye drops (artificial tears), gels and ointments are available as well as other treatments which our Optometrists will be happy to discuss with you.
Myopia is a condition in which near objects are seen more clearly than objects which are far away.
The main symptom is blurred distance vision. Short-sighted people often report difficulty distinguishing details on road signs and scoreboards.
Another common symptom is “squinting” the lids together in an attempt to see clearer. This works by narrowing the aperture they are looking through and therefore reducing the size of the blur circle on the retina inside the eye.
Myopia tends to first develop during adolescence as the eye grows to full adult size. Myopia occurs because of a complex interaction of hereditary factors and environmental near point stress factors which cause spasm of the eye focussing muscles.
“Visual hygiene” is extremely important in Myopia management (see Resources page), but visually significant Myopia is corrected with either contact lenses or glasses. Myopic spectacle lenses are thickest at the edge, but new spectacle lens technologies have been developed to produce thinner and lighter lenses so even the highest prescriptions will now have good cosmesis.
For more information on Myopia, including an animated example of the condition, please click here.
Hyperopia means a person can see more easily at far than at near.
Extra effort is required to try to clear the focus at all distances, resulting in eye strain and fatigue. This “strain” can manifest itself as headaches after close work, blurred near vision, tired eyes, difficulty adjusting focus from distance to near and near to distance, avoiding close work and short attention span for near tasks.
Common symptoms are associated with tasks which require continued visual concentration. It becomes a problem to maintain a clear focus on near objects; causing headaches and tired or aching eyes.
In some age groups a prescription for hyperopia often works to relieve the strain, rather than clearing the vision. This can be provided with glasses or contact lenses.
For more information on Hyperopia, including an animated example of the condition, please click here.
Astigmatism occurs when there is an out-of-roundness of one or more surfaces in the eye’s optical system.
An eye with no astigmatism is spherical in shape, like a marble. On the other hand an eye with astigmatism has a distorted shape, slightly like a grape.
In lesser degrees this can cause strain and discomfort after visual concentration; while in higher degrees astigmatism causes images at all distances to be distorted or blurred.
Visually significant Atigmatism can be corrected with glasses or contact lenses.
For more information on Astigmatism, including an animated example of the condition, please click here.
Presbyopia is a gradual loss in the focussing ability (accommodation) of the eye and is part of the normal vision changes we all experience with aging over time.
This is caused by a natural hardening of the eye lens, so that by the early 40’s the lens does not respond as well to the muscles intended to change the focus of the eye. As a result, people in this age group start to have difficulty with near tasks like reading small print, threading a needle, etc. This is especially true at the end of the day when lighting levels are poorer and the individual is more likely to be tired. Correction options include reading glasses, bifocals or multifocal (progressive) lenses. Contact lenses are certainly an otpion for presbyopia now too.
For more information on Presbyopia, including an animated example of the condition, please click here.
Macular Degeneration (MD) is a disease associated with aging that gradually destroys central vision. Central vision occurs at the macula on the retina, at the back of the eye. Because it is the central part of vision, it is needed for seeing objects clearly and for common everyday tasks such as reading and driving.
In some cases, MD advances so slowly that people fail to notice the gradual deterioration of their vision. In others, the disease progresses faster and may lead to a permanent loss of central vision.
While there is presently no cure for Macular Degeneration, there are steps that you can take to prevent or slow the progress of the disease and our Optometrists will be more than happy to discuss this with you.
MD is present in 15% of people between the ages of 70-75 and is now the leading cause of blindness and severe vision loss in Australia.
For more information on Macular Degeneration, including an animated example of the condition, please click here.
Amblyopia (Lazy Eye)
Amblyopia occur when there is reduced vision, generally in only one eye, even when the best optical correction is being worn. The condition usually results from poor eye co-ordination, from having a turned eye, or after having one eye which requires a far greater lens power than the other.
The reduced vision occurs because the brain tends to ignore the poor quality image it recieves from the affected eye. When detected early enough, treatment including patching, Vision Therapy and glasses or contact lenses, may help to reverse or prevent permanent vision reduction.
For more information on Amblyopia, including an animated example of the condition, please click here.
Eye Muscle Inco-ordinations
Eye muscle inco-ordinations (known as ‘phorias’ in mild cases, and ‘strabismus’ when more severe) occur when the eyes do not align or focus together as a team. This improper control of the eye muscles can result in crossed-eyes, poor focussing ability, or simply discomfort and headache from the extra effort required.
Common treatment options include glasses or contact lenses and Vision Therapy. Sometimes therapeutic glasses will be recommended incorporating, prisms, bifocal or progressive lenses.
For more information on phorias and strbismus, including an animated example, please click here.
Glaucoma is a disease where the pressure within the eye is typically increased (although not always). This can damage parts of the eye, and if left untreated may result in blindness.
Many times the symptoms are not noticeable until damage to the eye has already occurred. Diagnosis consists of having regular eye examinations which include a pressure measurement (usually every 2 years for patients over 40), to enable early detection of possible problems.
For more information on Glaucoma, including an animated example of the condition, please click here.
Cataract is an opacity or clouding of the lens inside the eye, then distorting the light as it enters. Cataract is often confused with pterygium but cataract cannot be seen on the surface of the eye.
Symptoms of cataract may include a gradual painless decrease in clear vision, hazy vision, increased sensitivity to glare, and even double vision.
Special tints or filters can often improve vision and UV protection can help to slow development of this condition.
The eventual “cure” is surgical removal of the lens with cataract and replacement with an artificial lens (intra-ocular lens implant). Typically this is done as a day-procedure under topical anaesthesia with no sutures or stitches required. Laser-assisted cataract surgery is also now an option.
For more information on Cataract, including an animated example of the condition, please click here.
Pterygium is a triangular growth of degenerative tissue on the white of the eye (sclera), usually on the nasal side, that may extend onto the clear window of the eye called the cornea.
A pterygium results from irritation due to long term exposure to ultra-violet light (UV), wind, glare or dust. Treatment involves wearing UV protective eyewear, with eye-drops to minimise irritation. If the pterygium is extending onto the more central part of the cornea whereupon it may start to affect the sight, then surgery may be necessary.
Spots & Floaters
Spots and floaters are semi-transparent specks of natural materials inside the eye, which sometimes can be seen floating in the field of vision.
Some patients comment that they look like cobwebs or threads, and most usually notice floaters when looking at a bright clear background like a ceiling or plain coloured wall.
They can be caused by debris left over from before birth, and they can occur as part of the eye’s natural aging process, bu they can also result from injury or eye disease. Recent onset spots or floaters require a full eye examination to determine the cause and whether any follow-up is needed.
Refractive surgery describes a group of procedures where surgery is used to correct the focus of vision rather than spectacles or contact lenses.
The most modern techniques use computer controlled lasers to remove a layer of the cornea (window at the front of the eye) and to reshape it to correct vision. Our practice is involved in the assessment of suitable candidates, referral of patients for this procedure, and follow up after the surgery.
Refractive surgery is best suited for patients who wear spectacles or contact lenses all the time. Most patients do not need spectacles for general wear after the surgery but it is likely that a prescription will often be needed for fine work or as focussing problems (presbyopia) develop naturally in the 40’s.
Originally, laser surgery could only correct short-sightedness. Now it offers hope to those suffering astigmatism (distorted vision) and long-sightedness. Laser surgery gives speedy results with minimal pain. But this procedure is not suitable for everyone. If you are under 18 years old, pregnant, or have had changes to your prescribed corrective lenses in the past year, we usually do not recommend laser surgery.
Cost is an important factor: laser surgery costs up to $3000 per eye and is not covered by Medicare or private health funds (though in some cases it is partially tax deductible). Most laser clinics offer finance plans or interest-free terms.
While laser techniques in refractive eye surgery have been years in the making, only in this decade has laser surgery become truly widespread. It is estimated that up to one and a half million people worldwide have had such operations, many thousands of those in Australia.
Reputable eye surgeons emphasise that not all laser patients will attain 20/20 vision. This depends on various factors, including the severity of the patient’s original vision problem. Some patients may still require glasses or contact lenses after laser surgery.
Those with presbyopia or “ageing eye” which often occurs in one’s early 40’s, cannot generally be treated by laser surgery, although in some cases monovision laser treatment may be used for one eye only.
Colour Vision and Colour Vision Deficiencies
A routine part of our eye examinations is an assessment of colour vision, especially for children.
Colour blindness is almost always inherited, although it can be acquired condition as a result of some diseases or injuries.
The abnormality is sex linked, recessive, and carried on the X chromosomes. This means that males need only have their one X chromosome affected to be colour blind while females must carry the condition on both their X chromosomes to be colour blind. If females have it only on one X chromosome they will carry the condition but still have normal colour vision themselves.
As a result, about 8% of males and less than 0.5% of females have colour vision deficiencies. Almost all colour deficient people do see most colours but they will have difficulty identifying particular ones, confusing certain shades of red and green for example.
As children, few of these people will be aware that they have a colour vision deficiency but the detection of these problems is important since many educational materials are colour coded in the early school years and colour vision is important when career choices are being considered.
For more information on Colour Blindness, including an animated example of the condition, please click here.
What is “Normal” for my vision?
It is normal for our eyes to be long-sighted at birth. This usually reduces as the eye grows to full adult size during adolescence. It is then in the teens that short-sightedness tends to develop, if at all.
After a relatively stable time in the 20’s and 30’s, another significant time for change begins in the 40’s. This involves a gradual loss in the ability to finely focus the lens inside the eye. The result is a totally normal and expected change called “presbyopia”, which continues into the 60’s.
After 60, the eye will tend toward less long-sightedness or more short-sightedness as the inner part of the eye lens hardens. Sensitive vision drops and the retina’s fine discrimination of colours is dulled. By age 70 most eyes show signs of cataract and the older, harder, clouded eye lens scatters light so that glare often becomes more of a problem.
How often should I have my eyes checked?
Your Optometrist will advise you of the interval between eye examinations which is appropriate for your vision and eye health needs. This time interval does vary for different situations, so we contact our patients when their next routine check is due. Changes in vision and eye health are often quite slow and subtle, and can easily go unnoticed if not checked regularly. As a general rule, you should have a routine eye examination every two years.
Of course if a problem arises sooner, or you have any concerns about your eyes or vision please make an appointment so that we can assess the situation for you.