Gerry & Johnson Optometrists

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While our practices have the latest in diagnostic equipment to detect any eye diseases that you may have, we also believe that our patients should be kept up to date on advances in the prevention of eye disease.

Gerry & Johnson Optometrists screens for and manages the following conditions:

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Myopia (short-sightedness)

Hyperopia (long-sightedness)

Astigmatism

Presbyopia

Cataracts

Many people think of a cataract as a 'film growing over the eye'. It is not a growth at all, but actually a normal, age-related change within the eye.

The crystalline lens of the eye is responsible for focussing light onto the retina (the tissue layer at the back of the eye which receives visual information), and when we are children, this lens is clear and transparent. As we get older, the lens begins to yellow and lose transparency, and when it gets to the stage where the quality of vision is compromised, it is termed cataract. A small degree of yellowing in the lens is normally observed in most people over 40-45, but it will not be termed 'cataract' until it begins to affect vision levels. People over 60-65 are more likely to exhibit cataract, but it can vary greatly between individuals of the same age.

While most cataracts are part of the aging process and long term exposure to UV light, some can be caused earlier in life from ocular injury, certain diseases of the eye or body and some medications, particularly steroids. In rare cases a child will be born with cataract, due to genetic problems or a case of maternal rubella (German measles) during pregnancy.

Development of age-related cataract is usually gradual, with common symptoms of blurred and hazy vision, floaters and spots before the eyes, double vision and sensitivity to sunlight and glare. Once diagnosed, the cataracts, which may be in both eyes but to differing degrees, are monitored until such time that surgery is required to remove the cloudy lens and replace it with a transparent artificial lens. When vision drops to a certain level, or the cataracts begin to interfere with daily life, surgery is recommended, but the decision is up to the individual. Cataract extraction is a simple and relatively quick procedure which is often done under local anesthetic at a day surgery.

Unfortunately, there is no proven method of preventing age-related cataracts, however high levels of UV exposure have been shown to increase the incidence and severity of cataract, so protecting the eyes from the sun is the best measure that can be taken. Gerry & Johnson Optometrists can diagnose and monitor signs of cataract and advise on the necessity of surgery.

Glaucoma

Glaucoma is a condition where the fluid pressure in the eye causes damage to the optic nerve, and can lead to blindness. A normal amount of pressure in the eye needs to be maintained so that the eye holds its shape and can function fully. This pressure is held by fluids in the eye (intraocular pressure), but just as pressure in the arteries and veins can become too high, the same can occur in the eye; although eye pressure and blood pressure are unrelated. Left untreated, an elevated intraocular pressure causes irreversible damage the optic nerve and retinal nerve fibres, resulting in a progressive, permanent loss of vision. However, early detection and treatment can slow, or even halt the progression of the disease.

Glaucoma is more complicated than a simple elevation in intraocular pressure (IOP), as what is 'normal' can vary from person to person. Some people can have a 'high' IOP but no signs of glaucoma, whereas some people may have a measured IOP within the 'normal' range but show glaucomatous damage to the optic nerve. Glaucoma can also be inherited - a first degree relative (parent or sibling) with glaucoma increases your risk of developing glaucoma by four times - but it also can develop as a consequence of general health problems; like diabetes, hypertension (high blood pressure) or those requiring steroid medications; or in conjunction with other ocular conditions like myopia (short sightedness), eye trauma and congenital malformations of the eye.

The elevation in IOP which leads to glaucoma results from either a malformation or malfunction of the fluid drainage system of the eye. The aqueous fluid, which sits between the cornea (clear window over the coloured 'iris') and the iris, is constantly produced in the eye, and drains out through a sieve-like meshwork which sits where the cornea and iris meet; called the angle. The delicate balance between the production and drainage of aqueous determines the eye’s IOP. There are many different types of glaucoma, dependent on the integrity of the drainage structures, the size of the 'angle' and the measured IOP. The majority of glacomas develop in adulthood, with a prevalence of 2-5% in people over 40 years of age. Glaucoma rarely causes symptoms until loss of vision is quite advanced - regular eye examinations are the only way to detect glaucoma in its early stages. A full eye examination including IOP measurement and periodic testing of the peripheral vision (visual fields) indicate the progression of glaucoma and the extent of any vision loss it causes. Treatment is usually by IOP-lowering prescription eye drops used once or twice a day, but in some cases laser treatment or surgery is required to clear the drainage channel.

Gerry & Johnson Optometrists has the latest technical equipment available to all patients to assess, diagnose and monitor glaucoma; including evaluation of the health of the optic nerve with digital imaging, computerised visual fields testing, and examining the anterior eye structures and the 'angle' with special lenses (gonioscopy). All full eye examinations include intraocular pressure checks and assessment for other eye health risk factors.

Macular Degeneration (AMD)

Macular degeneration is an age related condition of the macula - the central part of the retina which is responsible for fine detail vision and colour discrimination. Waste deposits from nutritional processes of the retina, which are usually removed in the healthy eye, accumulate in the macular area and compromise its function. As nerve tissue like that of the retina and macula cannot regenerate, once it is damaged, an irreversible loss of vision occurs. Age related macular degeneration (ARMD) can vary in severity from slight distortions of central vision to a complete loss of central vision which makes reading or driving impossible - but it does not cause total blindness as the peripheral (side) vision is not affected.

ARMD becomes more common as we get older - only 4% of people over 40 years are affected, but this increases to 23% in those over 65 and 31% in those over 80. One or both eyes, to different degrees, can be affected, and there is no gender difference in the frequency rates. In people over 70 years, up to 45% of people declared legally blind, and up to 70% of serious visual impairment cases can be attributed to ARMD.

There are two types of ARMD - the wet (neovascular) type, and the dry (atrophic) type. Wet ARMD accounts for only 10% of cases but is much more disastrous for vision - new blood vessels grow into the area of damaged macula to attempt repair, but these new vessels are fragile and easily rupture. Bleeding in the macular area can lead to sudden, irreparable drops in vision levels, but laser treatment to seal off the new vessels can help to slow the progression of the disease. Dry ARMD is much more common, and here a steady and less severe loss of vision is noticed from build up of waste materials causing tissue damage to the macula. Gerry & Johnson Optometrists have the latest digital imaging equipment which allows for permanent photographs of the retina and macula to be recorded, so any changes are easily and accurately noticed.

Macular degeneration can be caused by genetics, but age, nutrition, smoking, and sunlight exposure may all play a role. Many recent studies have centred around the role that nutrition plays in the development of ARMD - in particular, a diet high in fruits and vegetables (especially leafy green vegetables) provides antioxidants which are protective of the macular tissue. There are currently several multivitamin-type nutritional supplements - especially designed for sufferers of ARMD or those with a family history - which aim to provide these antioxidants in amounts scientifically demonstrated to be beneficial. Regular eye examinations which include eye health checks are necessary for people of all ages, but especially for those over 40 and/or with a family history of eye disorders like macular degeneration.

Diabetic Retinopathy

Diabetes can affect the eyes in many ways, but the greatest threat to vision is posed when diabetes affects the retina - the tissue layer at the back of the eye which receives the information of sight. When this occurs, it is called diabetic retinopathy. Just like diabetes can affect young and old, the same is true of diabetic retinopathy. While around 4% of the Australian population suffer from diabetes (with this figure on the rise as obesity becomes more common), more than 70% of these people will show signs of diabetic retinopathy by 15 years post-diagnosis. Any changes are best treated early for successful outcomes, so anyone with diabetes should have their eyes checked at least once a year to watch for any signs and risk factors.

Diabetes affects the retina when the small blood vessels at the back of the eye lose strength and begin to leak. Waste materials and small haemhorrages damage the retinal tissue. If the blood supply to a particular area is reduced enough, this area will lose its function and trigger growth of new blood vessels (neovascularisation). These new blood vessels are fragile and easily rupture. More abnormal vessel growth and scar tissue can lead to glaucoma, retinal detachment and blindness if left untreated.
The easiest way for someone with diabetes to reduce the risk of diabetic retinopathy is to keep tight control on blood sugar levels (BSL's). A healthy diet, regular exercise and stable BSL's play important roles in the overall health of a diabetic, and lead to fewer eye problems. Regular eye examinations are of the utmost importance as well - Gerry & Johnson Optometrists have digital retinal photography facilities to accurately and permanently record any signs of diabetic retinopathy, and to monitor for any changes.

People with diabetes may also develop cataract at an earlier age, and are at greater risk of developing glaucoma. They may also experience fluctuations in vision due to focussing problems and occasional double vision - any such problems or visual changes should prompt the diabetic person to seek consultation - a service which Gerry & Johnson Optometrists provides in an expert manner.

Keratoconus

Keratoconus is a degenerative condition of the cornea - the clear window over the coloured part of the eye (the iris) - that causes it to gradually thin and bulge outwards into a cone-like shape. This shape prevents light from focusing precisely on the retina, and blurred vision results. As the condition progresses, the cone becomes more pronounced, with vision becoming increasingly blurred and distorted from astigmatism, which describes the irregular shape of the cone-like cornea.

Keratoconus is often an inherited condition, and it has been linked to general health problems like allergy, hay fever and asthma. Forcible eye rubbing in people suffering from seasonal allergy problems like hayfever has been shown to relate to the onset of keratoconus. It usually occurs in both eyes, but can affect one eye more than the other. Signs of keratoconus include blurred vision even with spectacles, frequent changes in spectacle prescription due to progressively higher amounts of astigmatism, glare and light sensitivity.

Keratoconus is usually diagnosed by the late teens to early twenties, and may advance slowly or quickly. Corneal topography, a computerised test which maps out the curves of the corneal surface, can diagnose early keratoconus and aid in monitoring its progression. For most patients, once the irregular astigmatism can no longer be adequately corrected by spectacles, rigid gas permeable (RGP) contact lenses provide best vision. RGP contact lenses, as the name suggests, are not flexible, so by sitting on the cornea they create a new, regular surface for light to be focussed from and hence improve best-corrected vision. These contact lenses can be challenging to fit and often require a lot of fitting time to achieve the best result. Also, RGP contact lenses will need to be refitted as the keratoconus progresses. If the keratoconus progresses to such a stage that RGP's will no longer fit the conical cornea, or vision further deteriorates, a corneal transplant may be necessary to replace the diseased cornea with a healthy one.

Gerry & Johnson Optometrists has a long history in managing patients with keratoconus, including fitting of RGP's with highly successful visual outcomes. With the latest computerised corneal topography equipment, the diagnosis and management of keratoconus is uncomplicated and made easy to understand.

Hypertensive Retinopathy

People who suffer from hypertension – high blood pressure – can often show signs of this on the retina, the tissue layer at the back of eye which receives the information of sight. Just as high blood pressure affects the health of the arteries and veins in the body, so too may this be seen in the small arteries and veins (blood vessels) which overly the retina, supplying it with oxygen and nutrients and removing waste materials. If this supply is compromised by diseased arteries and veins, the health of the retina and optic nerve are affected, and this can have dire consequences for vision.

Signs of high blood pressure affecting the eye health - called hypertensive retinopathy - include narrowed arteries, hemorrhages, deposits of waste materials in the retina and swelling of the optic nerve where it enters the eye. If blood flow is impaired to a section of the retina, it will cease to function and the tissue will die. Nerve tissue, like that on the retina, cannot regenerate once damaged, and vision is permanently lost. The best preventative measure against hypertensive retinopathy is good control of blood pressure, which is normally managed with medication prescribed by a general practitioner or vascular specialist. People treated for hypertension should also have regular eye examinations to monitor for signs of retinal damage. For those not treated for hypertension, maintaining a healthy weight, a good diet, and quitting smoking all help to keep blood pressure in the normal range.

Digital imaging equipment available at Gerry & Johnson Optometrists takes permanent photos of the retina, which allow for regular monitoring for any areas of risk or evidence of hypertensive retinopathy.

Retinal Diseases

The retina is the thin tissue layer that sits on the inside back surface of the eyeball; it receives all the information of sight. Retinal nerve fibres carry sight signals to the optic nerve, which in turn takes the information back to the brain to be processed. Normal, healthy retinal tissue is required for this to function smoothly.

There are many ways the health of the retina can be compromised - eye infections and diseases, inherited structural problems, acquired conditions and even some medications. Although none are very common in the general population, some of the more frequently seen conditions of the retina are discussed here.

Congenital dystrophies of the retina are diseases present from birth, due to genetics, which result in degeneration of the retina. Some include Best diseases, Stargardt's disease, and Retinitis Pigmentosa. Although the gene for the disease is present at birth, many years may pass before the gene expresses and the disease is diagnosed.

Best disease is an inherited dystrophy of the macula, the part of the retina responsible for fine detail vision and colour discrimination. It is usually first diagnosed in childhood or as a teenager, by a characteristic appearance of the macula. Central vision may deteriorate over many years, but peripheral vision is left intact. A dominantly inherited disease, a parent with Best disease has a 50% chance of having a child with Best disease, even with an unaffected partner. The final vision levels vary greatly between sufferers.

Stargardt’s disease, often called fundus flavimaculatus, is another inherited condition of the macula which is usually noted before the age of 20. A progressive loss of central vision occurs – the peripheral vision is unaffected. The vision loss usually progresses to the level deemed legal blindness over many years. Stargardt's can affect either gender, and is recessively inherited, which means that both parents may be normally sighted but both are carriers of the defective gene.

Retinitis pigmentosa can be inherited from an affected or a carrier parent, and the first symptom a sufferer will notice is problems with night vision. Pigmentary (dark coloured, spindle-like) deposits in the retinal tissue are the hallmark of this condition, but may not be evident in early stages. In Retinitis Pigmentosa the peripheral (side) vision is affected, and at its end stage, although the very central zone of vision may be clear, a sufferer will have total tunnel vision. There is currently no cure for any of these inherited dystrophies but support groups and sophisticated low vision services are available to sufferers and their families where needed.

Acquired diseases of the retina are not inherited, and may present at any time throughout life. One of the more common conditions is retinal detachment - this may occur for any variety of reasons, but the more frequent causes are trauma, high amounts of myopia (short sightedness) and pre-existing conditions of the retina which may predispose to retinal detachment. The retina pulls away from lying flat against the inner back surface of the eyeball due to either traction (something pulling on the retina) or fluid seeping into the retinal layers and lifting it away (due to a hole, break or tear in the retinal surface). People at risk of retinal detachment should have regular eye examinations and always be aware for symptoms of flashes (like a lightning bolt going off in the eye) or a dramatic increase in floaters (black/grey/brown spots or lines in front of the eyes - having a few of these is normal), which if present, require immediate examination.

Gerry & Johnson Optometrists has the latest digital retinal photographic equipment, which allows for permanent pictures of the retina to be compared over time to assess for and monitor any inherited retinal dystrophies, or risk factors for retinal detachment.

Pterygium

A pterygium (said ter-ij-gee-um) is a wedge-shaped, raised lump of tissue which is an overgrowth from the conjunctiva - the thin membrane overlying the sclera, or white of the eye - which grows onto the cornea, the clear window over the iris, or coloured part of the eye. It can occur in one or both eyes, and is more often seen on the side of the eye closer to the nose. Although a pterygium is an overgrowth, it is important to remember that it is not a tumour or a cancer - but any area on or around the eyes that changes rapidly should be examined immediately to rule out something more serious.

Pterygia (plural) are related to dust, wind and UV exposure, and hence are quite common in Queensland, and in people who spend a lot of time in the sun like farmers, construction workers and surfers. Although they are benign, they can grow towards the centre of the cornea and distort vision by creating astigmatism (an irregular corneal shape). If this occurs, or if the pterygium tissue begins to block out vision, surgery is required to remove the pterygium. For most people with pterygium, however, growth is slow or dormant, and the worst symptoms are irritation, redness, itch and dryness, which are easily relieved by tear-supplement lubrication eye drops. Use of sunglasses, avoiding excess UV exposure (particularly between 10am and 4pm each day), and protecting the eyes from dust and wind can also help to halt the progression of a pterygium.

Treatment of a pterygium not requiring surgery is by monitoring for changes in shape and size, and ensuring that vision is not affected by its presence. Corneal topography assessment - computerised mapping of the surface of the cornea - can indicate the position and size of the pterygium on the cornea, as well as evaluating any possible effect on vision through corneal distortion. Gerry & Johnson Optometrists have cutting edge corneal topography equipment and software, which ensures that pterygium management is comprehensive.

Dry Eye

Dry eye is one of the most common conditions treated by optometrists. Dry eye can range from mild symptoms of stinging, burning and irritation to a pathological condition that endangers the health of the cornea and the quality of vision.

The tear film is made up of three layers which sit over the whole front surface of the eye; it is refreshed and resurfaced with each blink. Dry eye problems are usually due to a problem with one of the three layers (oil, aqueous or mucous layers), or a problem with resurfacing the tears (blinking problems). Just a few of the causes behind dry eye include eyelid infection or inflammation, ocular allergy and conjunctivitis, general medical problems including autoimmune disorders, hormonal changes like menopause, and taking some medications like antidepressants and the contraceptive pill.

In addition, environmental influences like the presence of smoke (cigarette or not), dust, airconditioning and wind; and doing lots of computer work or reading can all lead to dry eye problems. Contact lens wearers can also suffer dry eye symptoms. Treatment of dry eye varies greatly dependent on the underlying cause - which is assessed by a full eye examination. Many people find relief simply from regular use of tear-supplement lubricating drops. Some of these products are watery and alleviate the symptoms temporarily; others are thicker and adhere to the eye longer. Products that whiten the eyes should be avoided, as they don’t have adequate lubricating qualities and often make the problem worse.

Blocking the tear ducts in the eyelid with special inserts called punctal plugs is another option. These special plugs stop drainage of the tears and keep the tears on the eye, maintaining moisture. This may be done temporarily with a dissolvable collagen plug, or permanently with a silicone plug. Gerry & Johnson Optometrists are experienced in the use of punctal plugs on both a temporary trial or permanent wear basis.

There are also simple lifestyle changes that can significantly improve irritation from dry eyes. For example, drinking eight to ten glasses of water each day keeps the body hydrated and flushes impurities. Gerry & Johnson Optometrists advise adding essential fatty acids to the diet like Omega-3 and Omega-6 fish oils, which can improve the quality of the oily tear layer and the integrity of the tear film. Making a conscious effort to blink frequently – especially when reading or doing computer work - ensures that the tears are regularly spread over the eye surface. The correct treatment of dry eye problems is important not only for comfort, but also for the health of the cornea.

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