Eye Diseases

Macular degeneration (MD) is damage or breakdown of the macula.  The macula is a very small part of the retina (the light sensitive tissue), which is responsible for central vision. This is the part of the retina which produces the finest detailed vision.

In MD the side "peripheral" vision is usually not affected. For this reason it does not cause total blindness, and people can usually take care of themselves quite well.  MD is usually more advanced in one eye. The main symptom is deterioration of central vision, although this may only occur over a period and initially may not be obvious if only one eye is affected. Colour vision may also be affected.

MD occurs more frequently with age (4% of those over 40 years to 30% of those over 80 years), family history and some general health conditions such as diabetes, however some types are inherited, due to injury or inflammation of tissue.

There are several types of MD although the main two are "dry" and the more severe "wet" age‑related maculopathy (ARM). The "dry ARM" type account for 70%, the "wet ARM" for 10%.  Early detection of MD is important. Vision examinations may include a grid pattern (as over), which when observed with each eye may appear to be distorted or have parts missing.  

Treatment requires regular examination and consists of using both optical aids (magnifiers) and non optical methods (lighting).  The is no cure for "dry ARM", however fluorescein angiography may be used in "wet ARM" to detect blood vessel abnormalities which then may be treated by laser therapy to retard progression.

Also known as tear film dysfunction. Some people do not produce enough tears to keep the eye wet and comfortable.  Stinging, burning, scratchiness, foreign body sensation, photosensitivity, stringy mucus, and excess irritation from smoke are usually symptoms. Usually dry eye does not cause pain or blurred vision. Dry eyes may make it more difficult to achieve full-time contact lenses wear. 

Surprisingly, increased tearing may be a symptom of dry eyes.  If the basic tear secretion is below the normal, excess tears are produced by the lacrimal gland in response to irritation.  Even though the eyes are basically dry, overflow tearing may occur, masking the dryness which caused the tears in the first place. This is because there are two types of tears: those which are produced and lubricate the eye around the clock and those which are produced as a response to irritation such as foreign body or emotion.

Tear production normally decreases with age. Although dry eyes can occur at any age, women especially after menopause, are most often afflicted.  Dry eyes can be associated with arthritis and accompanied by a dry mouth. People with dry eyes, dry mouth and arthritis are said to have Sjogren's syndrome.  Medications such as antihypertensive, tranquilizers, analgesics, anti-emetics, oral contraceptives, antihistamines and oral anti-acne, can also cause dry eyes by reducing tear secretion.

Treatment is usually by:

Replacing the tears.

The use of artificial tears (ocular lubricants) is the basis of treatment.  Artificial tears are available without a prescription and are used to lubricate the eyes by replacing the missing moisture. There are many brands available, and you may need to try several types to find the one that suits you best. The artificial tears may be used as often as necessary, only once or twice a day, or as often as several times an hour. There are also water based lubricating gels on the market that have the advantages of artificial tears, but last for longer. At night-time eye lubricating ointments are sometimes required, however they are rarely used of a daytime because they temporarily blur vision. Ointments are only used in severe cases of dry eye.

Conserving the tears.

Preventing the evaporation of tears may also prove helpful. Wearing sun-glasses may cut down evaporation of eye moisture due to wind and cold air. In winter, when the heater is turned on, a humidifier adds moisture to the dry air. Avoid anything that adds dryness such as overly warm rooms, hair dryers, or anything that adds an irritant to the air will make a person with dry eyes more uncomfortable. Eg smoking, dusty areas.

Another approach to keeping your eyes moist in severe cases is by closure of the drainage holes (puncta). The closure creates a reservoir of tears which allows the eyes to stay moist for longer periods of time. Punctal oclussion may be temporary using plugs or permanent by surgical closure. This is rarely performed and only in severe cases.

Cataract is a cloudiness or opacity of the normally transparent lens inside the eye. It is not a film or growth on the surface of the eye, which can be cleaned off or peeled away.

The most frequent symptoms are blurred or dimmed vision and increased problems with glare. Cataract generally occur with advancing age but may occur at birth or any stage in life. Cataract is usually more advanced in one eye and may be slowly progressive over a number of years. Initially cataract causes very little problem.

The cause of most cataracts is unknown, except those resulting from injury ( traumatic cataract ).  Cataract is not caused by using your eye too much or by reading in poor light. There are several factors which may affect the occurrence of cataract and include;  age, associated with general health conditions such as diabetes, UV radiation , intense heat, some medications, a complication of some eye disease, smoking & family history.

Cataract cannot be cured by medicines, eye drops, diet or exercises and can only be removed by a surgical operation. Many cataracts develop slowly and never require surgical removal and are usually treated by more frequent alteration to your spectacles for prescription and tinting of lenses . The stage of removal is dependent on your lifestyle.

The most common surgery removes the cataract lens and replaces it with an intraocular lens implant ( IOL ). This may be done under both local or general anaesthesia. Age is no handicap, however good general physical condition is desirable. It is usual to have spectacles after the eye has healed to improve vision and these spectacles are often treated for maximum UV protection.  The prognosis is very good, however as with all surgery there are some unusual complications that may occur and this can be discussed with the eye surgeon.

Glaucoma is a condition in which the nerve cells which transmit information from the eye to the brain become damaged. This prevents visual information from getting from the retina in the eye to the brain. In most cases, glaucoma does not have any symptoms until late in the condition when permanent damage has occurred. The longer the disease if left untreated the greater the likelihood of damage. If untreated, glaucoma can cause blindness.

Glaucoma is often associated with a build up of pressure in the eye. The eye is normally filled with fluid, which is constantly being replaced. If excessive amount of fluid are produced, or if it cannot drain away properly, the pressure inside the eye can increase. In some forms of glaucoma, the pressure inside the eye can become extremely high, while in other the pressure may remain normal.

The exact causes of glaucoma are unknown. In some cases the drainage network of the eye may not be formed properly , or may become blocked by natural material or due to injury; in other cases there is no clear cause.

Glaucoma usually occurs after 40 years of age and often has a blood family history. Glaucoma cannot be prevented (except cases due to eye injury), but early detection by your optometrist and early treatment is the best way to control the problem. Regular eye examinations are important. Treatment usually involves using eye drops and in some circumstances laser surgery.

Diabetes affects around 420,000 Australians, or 2.5% of the population. Of these the vast majority of diabetics do not have any more vision problems than non-diabetes.  However, almost one in three suffer some form of damage to their vision, a condition known as diabetic retinopathy and detectable by your optometrist. Diabetes are advised to have yearly eye examinations, or more regularly if advised.

Diabetic retinopathy may occur after diabetes has been present for some years. These changes occur at the back of the eye in the retina. The are two stages of this condition, background (sometimes called simple) retinopathy and proliferative retinopathy.

Background retinopathy: This stage rarely causes any vision to be lost and therefore does not require any treatment other than regular eye examinations by your optometrist.

Proliferative retinopathy: This stage is more serious and requires early treatment to prevent serious vision loss. Your optometrist can recognise theses signs that the condition might develop or detect it in its early stages. Once proliferative retinopathy is diagnosed you will be referred to an eye surgeon for fluorescein angiography and possibly laser therapy. Treatment of this condition has a better chance of success if it is applied very early.

Other vision conditions which may occur as a result of diabetes include double vision, glaucoma and cataract. If present, glaucoma and cataract are readily detected at your regular eye examination when your optometrist will advise you of the best management strategy for the condition.

Optomeyes is a proud partner with Diabetes Tasmania. For more information on diabetes visit their website at www.diabetestas.com.au.

The Red Eye

"Ouch, my eye is sore and red, I must have conjunctivitis"

How many times have you heard someone say that? Sore, red eyes are very common, and it is very easy to assume that we just have 'conjunctivitis' and that some eyedrops will fix it. While that is often the case, it is vitally important to get the correct diagnosis before heading off to use drops that potentially could do more harm than good.

Bacterial Conjunctivitis.

This is the condition that everybody has heard of, and most people have experienced themselves. You wake up with a red, swollen eye, with lots of unpleasant discharge (pus, or sleep), and very sticky eyelids. It is caused by a bacterial infection, and can be contageous. Often, however, the bacteria causing the infection is one that normally lives happily on our bodies. Sounds gross, however, bacterial conjunctivitis is what is known as a self limiting condition. It follows a very predictable course, and should eventually get better by itself. Often, antibiotic eyedrops are prescribed to help resolve the condition, and prevent re-infection.

Viral Conjunctivitis

This form of eye infection is a lot more common than the bacterial form. It is also know as EKC, or Epidemic Kerato-Conjunctivitis. That's a mouthful!

It is very similar to getting a cold or flu, except that the site of the infection is the eye. Viruses of this sort are very difficult to eliminate from the body. Antibiotic drops do not have any effect. However, the good news is that, just like the common cold, our body is pretty good at getting rid of the infection itself. It just takes time. People with viral conjunctivitis usually have watery, red eyes, and may have recently had a cold or flu themselves. As a general rule, they do not get a sticky eye.

While the infection is going away, it is possible to treat the symptoms with lubricating eyedrops, cold compresses, and occasionally anti-inflammatory drops.

Allergic Conjunctivitis

Everyone is familiar with allergy problems like allergic rhinitis (hay fever). In the same way, allergy symptoms can be present in the eye. People with allergic conjunctivitis almost always have itchy eyes. They tend to be watery, slightly swollen, but not always very red. Their eyelids are often involved too. Allergic eyes are also treated with eyedrops, and there are literally dozens of drops that can be used to relieve the symptoms and treat the condition. There are new classes of drops that are able to treat the underlying problem, and not just mask the symptoms. These drops are called 'mast cell stabilisers' and are not available over-the-counter at the pharmacy. In general, they are much better at giving long term relief to the allergy sufferer. Another important consideration is that anti-histamine tablets, which are often used by allergy sufferers, can actually cause dry eye! You should speak to your optometrist if you are a regular user of hay fever tablets, especially if your eyes feel dry, or you wear contact lenses.

So, as you can see, there are many different forms of conjunctivitis, and indeed hundreds of other conditions that can give us red eyes. Your optometrist is perfectly placed to diagnose your red eye, to treat if necessary, and to refer for specialist medical care if required. In Tasmania, most optometrists are therapeutically qualified. This means that they can prescribe eyedrops for simple eye conditions, and you don't need a referral to see your optometrist. They will also work closely with your general practitioner, and can screen for other more serious eye conditions.

As you know, it is important to see your optometrist yearly to check for diabetic eye disease. And of course, if you are having trouble seeing, they can fix that too!

So, next time you have a red eye, don't just say "I've got conjunctivitis".

See your optometrist and find out exactly what is going on. It might just save you from unnecessary 'pain in the eye'...

By Andrew Hogan

 Andrew Hogan is consultant optometrist to the Tasmanian Institute of Sport, and the Tasmanian Cricket Association. He presents Optometry Talkback on ABC Local Radio.

While most of us take some measures to protect our skin from ultraviolet (UV) radiation, nearly half of Australian adults fail to regularly protect their eyes from UV damage.

Accumulated UV exposure can lead to cataracts, macular degeneration (a leading cause of blindness), cancer and pterygium (a fleshy growth on the cornea). Even short bursts of unprotected UV exposure can lead to pain, irritation and sensitivity to light.

All exposure to UV radiation, regardless of how short, adds up in the longer term.

The key to protection from harmful UV light is to start young and make it part of your child's routine.

How to avoid the effects of UV radiation

The simplest way of protecting your eyes from UV radiation is to limit your exposure.

1. Stay out of the sun between 10am and 4pm, when the sun's effects are strongest.
2. Make UV protection, including sunglasses or Transitions lenses, part of your everyday routine.
3. Ensure your eye protection meets Australian Standards.
4. Wear a hat. A broad-brimmed hat will protect your head from sunburn and reduce by half the amount of UV reaching your eyes.
5. For the best eye protection, choose sunglasses that have a bridge sitting as close to your eyes as possible without touching your eyelashes.
6. Be careful when choosing sunglasses for children; sometimes models that appear to be sunglasses are 'toys' that provide no protection.
7. Transitions lenses that automatically adjust to changing light conditions provide convenient UV and glare protection for prescription lens wearers.
8. If you have an existing lens prescription, check that your sunglasses prescription is also current.

*Copyright Optometrists Association of Australia 2009.