Eye conditions and diseases

Clearness of vision (Myopia, Hyperopia, Astigmatism)

Myopia, or short-sightedness, is an eye condition where objects can be seen clearly up close, but objects further away appear blurred.

Myopia occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. Most myopic eyes are healthy and are larger than normal – not that you’d see it, we are talking at a microscopic level.


Myopia is very common and is generally first picked up in school-age children who may frown or screw up their eyes in an effort to see. Short-sighted children may also hold reading material quite close or sit very closely to the television.


While myopia is often inherited, it can also occur in individuals with no prior family history of myopia. Myopia is not preventable and does not simply go away. Because the eye continues to grow during childhood and adolescence, myopia typically increases until about 25 years of age when it levels off. Myopia does not cause blindness.


The good news is that eyes with myopia are capable of good vision and require no treatment other than optical correction such as glasses, contact lenses, orthokeratology and in some cases refractive surgery.

Hyperopia, or long-sightedness, occurs when distant objects can be seen clearly, but those close up do not come into focus properly

In most cases it occurs when the eyeball is smaller than normal. Because of this, the eye cannot focus correctly.

  • Symptoms people with hyperopia may experience:
  • Poor vision unless they make an effort to see
  • Blurred vision when looking up from close work
  • Frequent eyestrain
  • Headaches and poor concentration
  • Occasional double vision
  • In children, progress at school is not as anticipated


Eye conditions caused by poorly focused vision are usually inherited. Hyperopia is a common eye condition in children. Since the size of the eye is the main factor that determines focus, and since the eyes continue growing until about 25 years, long-sighted eyes tend to become less long-sighted as a child grows older. However, all eyes slowly lose their ability to focus with age. Because of this, most people need reading glasses at some stage in their 40s.


Eyes with hyperopia are capable of good vision and require no treatment apart from optical correction or in some cases orthokeratology may be an option.

Astigmatism is a very common eye condition that causes blurred vision either close up or at a distance. This is because the cornea, the clear-fronted cover of the eye, is irregularly shaped.

We often explain this more easily by just saying the eye isn’t round, it’s rugby ball shaped.

Whether you are long-sighted (hyperopic) or short-sighted (myopic), you can still have some degree of astigmatism.


Slight astigmatism doesn’t usually affect vision or require correcting, however, larger amounts of astigmatism cause distorted or blurred vision, discomfort and headache. Astigmatism causes your eyes to work harder, which can make them tired.

The symptoms can range; some people get headaches, others just plain old blurred vision. Astigmatism doesn’t just affect your near or far vision, it can affect both. Astigmatism can also result in tired eyes, especially if you are concentrating on anything for a long period of time. This may be doing things that require looking up close (like working at a computer or studying) or at a distance (such as driving).


Glasses or contact lenses can be used to correct astigmatism. In some cases orthokeratology may be an alternative treatment. Vision will be clearer and more comfortable if astigmatism is corrected – even if a person sees quite well.

Colour Vision

People with colour vision deficiency are unable to see colours the same way that most people do.

They may have difficulty distinguishing between certain shades of colour, especially between red and green. Colour vision deficiency is often called colour blindness, but true colour blindness is rare: people with colour blindness see no colour at all, with things appearing black and white or in shades of grey.

Colour vision deficiency is more common in men than women affecting approximately 1 in 12 men and 1 in 100 women. In most cases the condition is inherited, although it can also develop as a result of injury, illness or from ageing. Colour impairment can sometimes be caused by the use of some drugs (both medicinal and illicit), alcohol or the fumes from some chemicals.

The three main types of colour vision deficiency are:

  • Red-green deficiency where people cannot distinguish between certain shades of red and green.
  • Blue-yellow deficiency where people cannot distinguish between blue and green. Yellow can appear as a pale grey or purple.
  • Total colour blindness where no colours can be detected. People with this condition have poor sight and are very sensitive to light.

In most cases people are able to adapt to having colour vision deficiency, although some professions such as the Police and Armed Forces require recruits to have normal colour vision.

Diabetic Retinopathy

Diabetic retinopathy occurs in people with diabetes when there is damage to the retina, the light-sensitive lining at the back of the eye.

In some people with diabetic retinopathy, blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina.

If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time diabetic retinopathy can get worse and cause vision loss. It usually affects both eyes.

Symptoms of diabetic retinopathy include:

  • Seeing spots or floaters in your field of vision
  • Blurred vision
  • Having a dark or empty spot in the centre of your vision
  • Difficulty seeing well at night

People who maintain a healthy lifestyle and control blood glucose levels are less likely to develop diabetes-related retinopathy.

However, it is very important that people with diabetes see their Visique optometrist regularly for an assessment of their eye health. With annual screening, any threats to sight that do develop can be detected and treated promptly minimising the risk of permanent loss of vision.

Focusing ability (Presbyopia)

Presbyopia is an eye condition where the lens of the eye gradually loses its ability to focus on things up close. In other words, it becomes difficult to see close objects clearly.

You may become aware of presbyopia when you start holding books or newspapers at arm’s length in order to read them. If you’re short-sighted, you might temporarily manage presbyopia by reading without your glasses.

Symptoms of presbyopia may include:

  • Problems with seeing small print, intricate details or small objects
  • Holding things further away in order to see or read them more clearly
  • Experiencing headaches, tired eyes or sore eyes when concentrating on close work or reading
  • Needing to adjust or amplify lighting to see clearly for reading or close work
  • Distance vision becoming strained or difficult following computer or close work

Presbyopia is a natural part of the ageing process and usually becomes noticeable in the early to mid-40s. It happens to everyone! With age, the eye’s lens thickens and gradually its flexibility decreases. As a result close objects appear more blurry than they used to.

There are many ways to correct presbyopia including reading glasses, progressive glasses and contact lenses. In some cases orthokeratology might be an option.

Because vision changes rapidly between the ages of 45-55 years, frequent lens changes may be needed.

Eye Muscle Control

Each of your eyes sees a slightly different image and your brain, through a process called fusion, blends these two images into one three-dimensional picture.

Good eye coordination keeps the eyes in proper alignment and is a skill that must be developed. Poor eye coordination occurs when vision or eye muscle control doesn’t develop adequately.

Because the images seen by each eye must be virtually the same, a person usually compensates for poor eye muscle control by using extra effort to maintain proper alignment of the eyes. In more severe cases, the muscles cannot adjust the eyes to see the same image anymore and double vision occurs. Because the brain will try to avoid seeing double, it eventually learns to ignore the image sent by one eye. This can result in amblyopia (lazy eye).

Some signs and symptoms of poor eye coordination include double vision, headaches, eye and body fatigue, irritability, dizziness and difficulty in reading and concentrating.

A comprehensive examination by your Independent Optometry Group optometrist will be able to detect any poor eye coordination. Either special glasses or eye exercises can relieve this problem.

Amblyopia (lazy eye)

The brain and the eye work together to produce vision. Amblyopia occurs when the vision in one of the eyes is reduced because the eye and brain are not working together properly.

The eye itself looks normal, but is not being used normally because the brain is favoring the other eye. This condition is also sometimes called ‘lazy eye’.

Symptoms of Amblyopia (lazy eye) include:

  • Eyes that do not seem to work together
  • Eyes that turn in or out
  • Poor vision in one eye
  • Inability to accurately judge depth

Amblyopia is a common concern for the optometrist in relation to children, affecting approximately 2 to 3 out of every 100 people. It may be caused by strabismus, or turned eyes. Sometimes amblyopia is caused when one eye is more short-sighted, long-sighted, or astigmatic than the other eye. Occasionally amblyopia is caused by other conditions such as cataracts.

Children who receive treatment before seven years of age usually have a near complete recovery of normal vision. However, amblyopia will not go away on its own. If not detected until pre-teen years or later, treatment takes longer and may be less effective. Most cases can be corrected with glasses or, in rare cases, with surgery.

Macular degeneration

Macular Degeneration is an eye condition associated with ageing where the macula – the part of the eye that allows you to see fine detail – gradually deteriorates, affecting sharpness of vision.

When this happens it can lead to difficulty reading and the need to give up driving. Some people even notice distortion to their vision.

The risk of developing Macular Degeneration is higher in people with a family history of the condition, those with certain medical conditions (e.g. diabetes) and in smokers. It is one of the leading causes of blindness in New Zealand, affecting 1 in 7 New Zealanders.

The frequency of this condition increases with age. However, a healthy diet with plenty of leafy greens can help prevent or slow the progression of Macular Degeneration.

Macular Degeneration tends to progress slowly and usually involves blurring in the central vision – peripheral vision is not affected. Sometimes vision may become distorted, with straight lines appearing crooked. There are two types of Macular Degeneration, the common one progresses very slowly. Your side vision is never affected in this disease, only the central vision. If you think you might be at risk, or have experienced some of the signs of Macular Degeneration, free information packs are available at your local Visique, and you can speak to an optometrist if you are concerned.

While Macular Degeneration may cause problems with vision, it rarely leads to total blindness. Macular Degeneration is a disease of the retina which is the light-sensitive layer of tissue, lining the inner surface of your eye. Recently there have been great advances in our knowledge and understanding of Macular Degeneration, and there are new treatments available to treat and prevent this devastating disease.


Glaucoma is the name for a group of eye conditions where an increase in fluid pressure inside the eye gradually damages the optic nerve causing vision loss.

Because the loss of vision happens slowly, a person with glaucoma may not notice any changes to their vision until a significant reduction in sight has occurred. Without treatment, this loss continues until the eye is blind. It may surprise you to know that you often can’t feel any increase in the pressure of your eye. The only way to know is to get your optometrist to measure it. The other reason that glaucoma is often called “the silent thief of sight” is that it damages your peripheral vision. We are all aware of what blurred vision may be like, but we cannot accurately measure our side vision or be aware if it has changed. Every Visique optometrist can measure your peripheral vision and monitor it for change.

Even if you think you’ve got perfect vision or that your current contact lenses or glasses are suited to your eyes, it’s important to get your eyes tested at least every two years.

“Too many people suffer with eye conditions without knowing just how bad their eyesight has got. All too often we examine people in our community who don’t realise how badly their eyesight has deteriorated. A customer I saw earlier this year came to the practice after he failed a routine driver’s licence renewal eye test. At 45 years of age, he hadn’t noticed that his eyesight had changed much at all. After examining him we found he had advanced Glaucoma in his left eye and early signs of the disease in his right eye. Glaucoma affects the eye very slowly, so it’s common for people not to notice how much of their vision they’ve lost. Our customer said he had no idea how badly his sight had deteriorated, let alone that he had glaucoma: While it’s devastating that we caught the disease too late and that he’ll never be able to drive again, the fact that the disease has now been detected means he will hopefully maintain my current level of sight with the help of laser treatment. He wished that he had tested for Glaucoma earlier."

There are three main types of glaucoma:

  • Chronic glaucoma is the most common type where the drainage channels slowly become blocked over many years.
  • Acute glaucoma occurs when there is a sudden blockage of the drainage system. This is painful and causes permanent damage to sight if not treated promptly.
  • Secondary glaucoma is where injury, inflammation or tumour blocks the drainage channels.
  • Anyone may develop glaucoma, but the risk tends to increase with age (about 2 in 100 New Zealanders over 40 years of age have glaucoma) and is more likely if there is a family history of glaucoma.

While glaucoma cannot currently be prevented, early treatment can help protect your eyes against vision loss. Because there are often no symptoms at first, regular eye examinations with your Visique optometrist, especially for those over 40 years of age, can help detect glaucoma in its early stages.


Cataracts are a common eye condition that causes vision to deteriorate in older people. A cataract is a cloudy area in the normally clear part of your eye called the lens.

Depending on how big the cataract is and where it is, it can interfere with your sight. This is because a cataract acts like frosted glass, causing your vision to become blurred.

A cataract is the change to the natural lens in your eye. Cataracts’ growth is just like frying an egg… when we are young the lens in our eye is clear – just like a raw egg white. But as we age the lens gets cloudy – just like a cooked egg white. It’s no wonder it affects your vision. Cataracts are just part of growing older, you can’t do anything to prevent them, or to speed up the process. Surgery is required for cataracts if they get bad enough.

Cataracts usually form very slowly and develop in both eyes, although one may be worse than the other.

The eye is one of the most complex organs in your body and it relies on many intricate structures for you to see clearly – any slight changes can have a large effect on your vision and can be symptomatic of broader health issues.

“When I examined him I found he had significant cataracts in both eyes. I also checked his blood pressure and found it was very high. So we sent him to a local GP and an ophthalmologist. He has since found out he has Diabetes and has had cataract surgery on his right eye, so we’re very glad we were able to pick up these issues when we did. Our customer said that this time, having his eyes checked was a life-changing experience for the good. He said that his eyes are connected to your general health and it was his eye test that led to being diagnosed with Diabetes. So he was very happy that he took the time to get his eyes checked."

Common symptoms of cataracts are:

  • Blurry vision
  • Colours that seem faded or washed out
  • Increased sensitivity to glare from lights (e.g. sunlight or car headlamps)
  • Not being able to see well at night
  • Frequent prescription changes to eyewear

As we get older many aspects of our vision change, therefore, it is important to make regular visits to your optometrist. Surgery to remove the cataracts may be needed later, but until then your optometrist can monitor any changes in your vision and help you to get the most out of your eyesight.


A pterygium is a pinkish, triangular-shaped tissue growth on the cornea.

Some pterygia grow slowly throughout a person’s life, while others stop growing after a certain point. A pterygium rarely grows so big that it begins to cover the pupil of the eye.

Pterygia are more common in sunny climates and in people between 20 and 40 years of age. No one knows what causes pterygia but people with pterygia have usually spent a significant amount of time outdoors.

Because a pterygium is visible, many people want to have it removed for cosmetic reasons. However, it is usually not too noticeable unless irritated by dust or air pollutants.

Protective glasses, sunglasses and/or hats with brims are recommended when sunlight is strong. Your optometrist can advise on suitable UV protection for preventing or minimising pterygia and can also refer you to an ophthalmologist if necessary.

Refractive laser surgery

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.

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 focusing problems (presbyopia) develop naturally in the 40’s.

Originally, laser surgery could only correct short-sightedness. Now it also 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.

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.

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.

Spots and floaters

Spots (often called ‘floaters’) are small cloudy specks that float about in your field of vision. They move as your eyes move and seem to dart away when you try to look at them directly.

Most people have floaters and they are usually not noticed until they become numerous or more prominent. They can become obvious when looking at something bright, such as white paper or a blue sky.

In most cases floaters are part of the natural ageing process. They can be distracting but eventually tend to ‘settle’ at the bottom of the eye below the line of sight. However, occasionally floaters can be a sign of more serious eye conditions.

If you notice a sudden change or increase in them, then you should see your optometrist.

Frequently Asked Questions

If you or a family member answer yes to any of these questions below you should book yourself in for an eye test at your local Visique optometrist.

While these symptoms are not necessarily specific only to eye problems or vision correction there are many issues that can occur with your eyes that may cause these symptoms.

  • Do you get headaches, nausea or dizziness after near tasks such as computer use or reading or after driving?
  • Do you get blurred or double vision at any time?
  • Do you ever get crossed or turned eyes?
  • Do you blink or rub your eyes after visual concentration?
  • Do you dislike or avoid any close work, such as reading or sewing?
  • Do you suffer from a short attention span?
  • Do you often place your head close to a book when reading or writing?
  • Do you often frown while looking at the TV or whiteboard?
  • Do you have difficulty reading small print?
  • Do you have difficulty adjusting focus between near and far objects?
  • Do you feel uncomfortable or avoid driving at night?
  • Do you have difficulty seeing road signs or TV?
  • Are you sensitive to the glare?
  • Do you have a family history of any eye disease?
  • Do you get sore or red eyes?

It is normal for most eyes to be long-sighted (hyperopia) at birth.This usually reduces as the eye grows to full adult size during adolescence. It is then in the teens that short-sightedness (myopia) tends to develop, if at all.

After a relatively stable time throughout 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 lens located in the inner part of the eye hardens. Sensitive vision drops and the retina’s fine discrimination of colours is dulled. By 70 most eyes show signs of cataracts and the older, harder, clouded eye lens scatters light so that glare often becomes more of a problem.

The eyes are our windows to the world; in fact almost 80 % of all the sensory information our brain receives comes from our eyes. So it stands to reason that looking after the health of our eyes is important throughout our lifetime Your Visique optometrist will advise you of the interval between your full eye and vision examinations that is appropriate for your vision and eye health needs. This time interval does vary for different situations, so we contact our clients 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.

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.

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