Common Eye Conditions
For more information visit nzao.nz and select Eye Health
Short sight, occurs when the eye focuses light too quickly resulting in the image being in front of the retina. This usually occurs when the eyeball is too long. This causes near vision to be clear but blurred at a distance. Spectacles, contact lenses or refractive surgery may correct Myopia.
Myopia can occur at any age but often begins in childhood, during the teenage years, or early twenties.
See the section on Myopia Control in the section about Children’s Vision.
Long sight, results in blurred near vision and in extreme cases distance objects may also be affected.
Hyperopia occurs when the eyeball is either too short or the lens of the eye is not curved enough.
Those with Hyperopia are required to make a greater effort than normal to focus. This may then cause the eyes to turn in resulting in crossed eyes and sometimes a ‘lazy eye’ may develop.
A child with Hyperopia might get more tired when reading or writing or may suffer headaches when copying from the blackboard. They may experience blurry vision at times, more often when doing close work.
With age, the focusing mechanism of the eye becomes less flexible requiring reading glasses earlier than is normal in middle age.
Spectacles and contact lenses are prescribed to relax the eyes and provide more comfortable clear vision.
‘Middle-aged sight’. There is a gradual deterioration in the ability of the eyes to focus at closer ranges, as we get older. This occurs as a result of reduced flexibility of the eye’s natural lens. Symptoms such as difficulty reading and arms not being long enough generally appear in the forties and sometimes tiredness and headaches occur more often.
At this stage some help is required in the form of reading glasses, or for those who already wear spectacles, there are multi-focal lens options. There are also multi-focal contact lenses available to correct presbyopia.
Astigmatism is a very common focusing error of the eyes which can cause blurred vision at both distance and near. It occurs as a result of irregular curvature on the surface of the cornea or on the lens of the eye itself. You can be born with astigmatism or it may develop as you age.
Astigmatism can also occur in combination with either myopia or hyperopia.
People with astigmatism often experience tired eyes and may experience increased sensitivity to glare. They are often found to ‘squint’ in order to try and improve their vision.
Both glasses and contact lenses can correct for astigmatism.
When your eyes don’t make enough of the right kind of tears, the surface of the eye is not properly protected. Discomfort from itching to pain, redness, stickiness and blur can all be symptoms of Dry eye – also called Ocular Surface Dysfunction.
Many factors can contribute to Dry Eye, , from allergies and medications you take, your environment, ethnicity and age, as well as the use of screen based devices and air-conditioning or heat pumps. There are two main types- evaporative and aqueous insufficiency.
A dedicated series of tests can find out if you have dry eye and what is the best mix of treatments to alleviating the symptoms.
Eyes are particularly likely to experience the itching, watering and redness when affected by allergies.
But sometimes it is not an allergy after all! Mild infections and Dry Eye can mimic the symptoms. We can identify whether your sore red eye is an allergy and advise on the best treatment.
Glaucoma is often referred to as the silent thief of sight and is one of the leading causes of blindness. Approximately 2% of people over the age of 40 have Glaucoma with the risk increasing with age. Glaucoma is an eye disorder resulting from damage to the optic nerve. This often occurs due to an increase in the internal eye pressure- but not always. Several tests may be required to diagnose glaucoma and early detection is important. Glaucoma cannot be prevented, but if diagnosed and treated early, it can be controlled. Vision already lost to Glaucoma cannot be restored.
For more information, visit www.glaucoma.org.nz
A cataract is a clouding of the normally clear lens within your eye resulting in blurred or distorted vision. Cataracts are most often found in persons over age 55.
Although cataracts develop without pain or discomfort, indications of cataract development may include blurred or hazy vision, increased sensitivity to glare or the feeling of having a film over the eyes.
If the cataract develops to the point that it affects your daily life and spectacles and contact lenses no longer help, you will be referred to an eye surgeon who may recommend surgery to remove the natural lens and replace this with a new plastic lens.
Headaches and Migraines
Headaches are more often caused by muscle tension that eyesight problems – but we scrunch up our eyes to see more clearly, or to stop glare. Habits of posture at work or when driving, and problems with the way the two eyes work as a team can also cause headaches – so it’s a good idea to have your eyes examined if you are getting headaches. Hypertension can also lead to headache, and we may see signs of this in your eyes.
Migraines are a certain type of headache and are often accompanied by visual disturbances like sparkling lights at the side of your vision that last from 5 to 30 minutes.
Getting migraines for the first time as an adult should be investigated, as there can be serious causes.
Hypertension (High Blood Pressure)
Signs of high blood pressure often appear first in the eye. Indicators can include narrowing of the blood vessels, spots on the retina, or bleeding in the back of the eye.
Flashes, Floaters and Retinal Detachment
Retinas can lift or pull away from the wall of the eye. If not properly treated, this can cause permanent vision loss. Signs and symptoms include sudden onset of floaters or spots in your vision, white flashes or a shadow or curtain affect obscuring your field of vision. If you experience any of these symptoms, contact your Optometrist or an eyecare professional immediately.
Not all floaters mean that there is a retinal detachment, but it is important to have a thorough check if you suddenly develop a new or different floater, to make sure this very serious problem is not missed.
A dark spot at the back of the eye may signal a melanoma, which can grow unnoticed within the retina. If caught early, melanomas can be treated before they cause serious damage and travel to other areas of the body through the bloodstream. Our photos and OCT technology are very helpful in finding this condition.
The macula is a small specialised central area of the retina, responsible for fine detail and colour vision. Macular Degeneration is usually a slowly progressing disease where the central area becomes thin and damaged, resulting in reduced function.
A more severe form of Macular Degeneration exists and can cause sudden deterioration of sight. In this condition blood vessels growing under the macula leak fluid or blood, which disrupts the smooth, even surface of the retina and damage the retinal cells. Vision becomes distorted and eventually reduces considerably. Early indentification and action is important, as some forms of Macular Degeneration respond to treatment; however, lost vision is often not restored.
Regular OCT scanning is the best technology to detect and monitor Macular disease.
For more information visit www.mdnz.org.nz
More than 80% of what we learn is through vision. That’s why checking children’s eyes and vision is
important. The B4 School eyesight and hearing test at age 4 helps find children with serious problems, but many difficulties come along as a child grows older.
Here is some detailed information about problems that come on in childhood – but continue to have effects and cause problems in later life too.
Binocular Vision problems
We have two eyes and they need to work together. When that doesn’t happen easily or can’t be sustained for long enough, vision can be blurred or double; the eyes get tired and sore and people often get headaches.
This can happen at any age and affect driving, sports performance, balance, reading, and using screen based technology.
The first thing to investigate is whether the eyes are making too much effort to focus, because that affects how they line up with each other. We can find that out if there is something more serious that is the cause of poor teamwork of the eyes, we can refer you for more specialised help.
Children who are having trouble learning to read; and adults who get sore eyes or have to make their phone font bigger to see it properly, should have a Comprehensive Eye Examination to check out the cause.
If the two eyes can’t focus clearly and line up with each other at the same time right from very early life, one eye may fail to develop the nerve connections between eye and brain which ensure the ability to see detail. Amblyopia develops in the years before age 4, so treatments needs to start early.
A child who is very longsighted or has some other cause of poor vision may develop a turned eye (crossed eyes, “squint” or strabismus) but sometimes the eyes appear to line up normally, which makes it hard to detect.
Early signs of amblyopia include rubbing one eye a lot, clumsiness or poor co-ordination, and disliking having one eye covered while covering the other is not a bother.
If you suspect there is poor sight or see your infant’s eyes turn even some of the time – contact us for a check.
Treatment of amblyopia is with spectacles or contact lenses and patching or eyedrops to make the “bad” eye work and develop the nerve connections it needs, are often part of the treatment.
All around the world children are developing myopia at a younger age and faster than ever before.
What happens in myopia is that the eyes get longer – they increase in “axial length”. That leads to stretching of the tissue and sets the eyes up for damaging consequences that come along in middle adult life – ages 50-60 plus. Cataracts, retinal detachment and a type of macular degeneration called Myopic retinal Degeneration are 3 to 10 times more likely to happen to people with myopia – even low amounts . The earlier it starts , the worse it gets, and the eyes are more likely to be damaged in later life.
Reasons for more Myopia : There is a lot of research looking into this and it seems so far that the cluster of modern life habits such as
Living in cities where everything is close and people never look out to the horizon
Spending time indoors where the light levels are from 5 to 10 times less than outdoors
Spending long periods of time looking at very close detail – screen-based devices, books – even factory assembly work
Having one or more parents with myopia
Myopia prevention and slowing myopia development is a task that all optometrists are being called on to do. There are a number of options at present:
Self help by families is summed up as “Outdoor play keeps myopia away”. The research says that 2 hours a day outdoors – and not looking at screens – is effective in reducing and delaying the increase in axial length.
Technical help from special spectacle lenses and contact lenses: these have to be used 90% of the time a child is awake, but they reduce the progress and axial length increase by about half.
Medical help – treatment with eyedrops is very effective but you need to see an Eye Specialist for this and it has to be continued for several years, typically between ages 8 and 15.
Keratoconus – Cone-shaped Cornea
The front surface of the eye – the cornea – should be a smooth curve. In some people however the tissue stretches and grows into a pointed shape – like a cone. The cornea gets thinner and distorted.
Keratoconus usually starts in mid childhood – age 8 to 10. Vision is blurred and the early stages shows up as astigmatism. However there can be very rapid progress in one eye that is not noticed and it’s only when the second eye changes that the child complains.
There is a very effective treatment to stop and slow this process called corneal cross-linking. The earlier this is done, the better, because it retains the near-normal shape of the cornea. Progression – further stretching and distortion – is slowed. Progression can be continuous but slow well into adulthood, so treatment may be appropriate at an older age too.
Children who get keratoconus often have a family history of the disease, and very frequently have multiple allergic conditions – asthma, hayfever, eczema. Eye rubbing – really hard rubbing with the knuckles – is a common habit that happens with children who develop keratoconus and it is thought to make the condition worse. Children who rub their eyes a lot should have them checked for keratoconus , and for allergy too. Good allergy control will reduce the eye rubbing so there is less risk of keratoconus developing.
The eyesight can really only be satisfactorily improved with hard contact lenses which are complex to fit, and we refer to specialist contact lens clinics for this treatment. Early treatment makes this far less difficult.
We are accepting new patients and new bookings, but the comprehensive examination appointments will be about 6 weeks ahead. For urgent requests, please phone us an we will assess the urgency; For breakages please call in, we may be able to make a temporary repair.