FAQ
Frequently Asked Questions about eye care, eye wear and vision. You can’t always see eye disease coming is why you need an eye exam for good vision for life.
Apart from visual function damage from the sun, diabetes, hypertension,cancers,nutritional deficiencies among many other possibilities can be detected.
Yes. Because subjective responses are crossed checked with objective findings and instrumentation. The purpose is to find the most comfortable and accurate focusing for youe eyes>
A comprehensive eye exam considers multiple tests and investigations for the best vision and eye health outcome
Bring all your glasses, sunglasses, contact lens products ,medication lists, family and any relevant personal eye and health history, to your eye examination.
The condition of your eyes can change over time. Some eye conditions develop so gradually (and why family history is important) they may not be recognised until regular eye exams are undertaken
The American Academy of Ophthalmology recommends having a comprehensive eye exam every five to 10 years if you’re under 40 years old; every two to four years if you’re 40 to 54 years old; every one to three years if you’re 55 to 64 years old; and every one to two years if you’re older than 65. For example if you’re at risk of glaucoma you would need more frequent reviews.
The amount of the medicare rebate depends on how long it has been since your last eye examination but is typically around $70. Some advanced additional tests that are not claimable on Medicare may be discussed if required. Private health fund claims can be processed using HICAPS
No health fund Gap spectacles and means tested free Government specatcles are also available.
The vast majority of optometric consultations are covered by Medicare and are bulk billed when eligible in most cases.
Eligibility of services is capped to within certain time frames.
When consultations are not covered by Medicare, such as for the fitting of low powered or coloured contact lenses or for advanced diagnostic scans this would be discussed during the individual consultation
No health fund Gap spectacles and means tested free Government spectacles are also available. The price of glasses varies widely with frame prices and lens prices. Despite some marketing claims they are not all the same and have to be a tailored for a specific prescription.
Private health fund claims can be processed using HICAPS
Drops may be used to dilate your pupils to allow for more complete assessment,to allow eye pressure testing,tear film diagnosis or to treat and investigate inflammation and infection.
You should generally have your eyes checked at least once every 2 years. Certain exceptions would apply. A routine eye check may lead to the early diagnosis and treatment of a condition before any irreversible vision loss has occurred. People who wear contact lenses, have health conditions (e.g. diabetes or rheumatoid arthritis) or have a family history of eye disorders may require more frequent eye checks.
Referrals are not essential to see an optometrist as most routine eye care can be comprehensively provided.
However if a referral is required to an an Ophthalmologist or Subspecialist Ophthalmologist that can be provided.
To avoid a viral (or bacterial/fungal/parasitic) infection.
1. Wash your hands regularly
Many viruses can survive for long periods outside the body (hours to days), particularly on hard surfaces like plastic and stainless steel. Washing your hands regularly and thoroughly with soap and water can kill viruses and bacteria on the surface of your skin.
2. Avoid touching your face
Each time you touch your eyes, nose or mouth you are risk of getting a virus.
Rubbing stimulates tear production, which provides temporary relief by lubricating the eyes and removing irritants. Conjunctivitis can be caused by viruses or bacteria – both are highly contagious and can be transmitted from person to person through direct or indirect contact with fluids from the eye. Conjunctivitis is frequently associated with upper respiratory infections.
Never share makeup (face or eye) with anyone else and clean pillowcases weekly
A virus is a tiny infectious agent made of a string of genetic material and a protective protein coat. Outside of a living cell, a virus is dormant and incapable of reproducing. Your eyes can be a portal for infectious diseases. Viruses make us sick by disrupting the function of, or destroying cells in our body.
Corneal abrasions (scratches) are the most common type of eye injury. No matter how minor the injury seems, it’s important to have checked to ensure it doesn’t develop into a bigger problem. Always wear eye protection to prevent a foreign object scratching or penetrating the cornea.
Regular eye exams are the key.
Dietary factors : Good nutrition Foods rich in omega-3 fatty acids ,such as salmon and flaxseed ,vitamins A, C, and E, as well as the mineral zinc that contain antioxidants that can help prevent macular degeneration ( Lutein and zeaxanthin carotenoids help protect the macula by improving pigment density, absorbing the toxic ultraviolent and blue light)
Exercise to reduce risk of Type 2 diabetes
Control of blood pressure and chronic inflammation
Protective eyewear, goggles and sunglasses.
Follow the 4×20 rule 20-20-20-20 rule meaning every 20 minutes, you should stop staring at your computer and look at something 20 feet away for 20 seconds with 20 blinks.
Quit smoking
Understand your family’s eye health history
Before a virus can cause a disease, it must first enter the body of its target host. The virus may be picked up via direct contact with infected droplets or indirect contact. If infected droplets come in contact with a mucous membrane like the eyes, nose or mouth, the virus can then enter your body and attack your cells. Viruses can be contagious even when the infected person has no symptoms and they can survive outside of the human body for some time. The most effective way to prevent t viral transmission is to ensure good hygiene practices, social distancing and PPE
Visual therapy is a series of activities undertaken to improve either poorly developed visual motor or visual perceptual skills and hence visual fitness.
Age and history are relevant eg head injury, whiplash or concussion?
Medications?
is the vision blurry, or is it double horizontally/ vertically/ obliquely? Are the images moving/ jumping?
Dizziness and end-gaze diplopia/blur/nystagmus suggests cerebellar issues, which can be developmental or acquired. The history will often suggest the diagnostic possibilities and if neurological signs or symptoms a workup is required.
Alcohol consumption does increase the risk of Dry Eye Syndrome (DES). For heavy drinkers, peripheral neuropathy caused by alcohol consumption may decrease their corneal sensitivity, so the real severity of DES is underrepresented.
Dry Eye Treatment Dry eye disease or syndrome is caused by a chronic lack of sufficient lubrication and moisture on the surface of the eye. There are a range of dry eye treatments that provide short and long term relief.
Chronic dry eye occurs when there is insufficient lubrication and moisture on the surface of the eye. A layer of tears normally covers the cornea to keep it moist. Small meibomian glands in the eyelids secrete oils that reduce evaporation of the tear layer.
Chronic dry eye can be caused by inadequate tear supply or excessive evaporation of tears, resulting in a deficient tear film.
Meibomian gland dysfunction (MGD) is one of the most common, if not the most common, causes of dry eye. It occurs when the meibomian glands don’t secrete enough oil into the tears, leading to rapid evaporation of the tear layer.
Symptoms of chronic dry eye occur because of corneal inflammation and irritation. Symptoms can include a gritty sensation, feeling like something is in your eye or even excessive watering/tearing.
Other signs include red or itchy eyes, a burning sensation, pain, light sensitivity or fluctuating vision.
MGD is typically a life-long condition requiring ongoing management techniques to soothe dry eyes. Early diagnosis and dry eye treatment offer the best chance of symptom relief and prevention of disease progression.
There is no one particular best cure but the aim is to restore the tear layer and ensure good eye hygiene. Dry eye treatment may involve a combination of simple home remedies (e.g. warm compresses), dry eye lubricants or dry eye ointments, prescription eye drops and sometimes even natural remedies such as flaxseed oil. Another natural remedy for dry eyes is Optimel Manuka+ Dry Eye Drop, containing active Manuka honey developed from Leptospermum sp.
Evidence suggests that MGD and tear deficiency may be associated with an overgrowth of bacteria on the surface of the eye. This overgrowth of bacteria is thought to lead to tear film instability and eye surface damage. Active Manuka honey is well known for its anti-inflammatory and anti-microbial properties. Research studies confirm that Manuka honey is an effective treatment for a range of eye conditions, including dry eye relief. It achieves this by lowering the pH and reducing bacterial overgrowth and inflammation, thereby stabilising the surface of the eye.
No serious side effects have been observed, but active Manuka honey preparations such as Optimel can cause initial stinging and redness when applied. Dry eye can also be seen following cataract surgery, affecting both patient comfort and visual quality.
A neuro-ophthalmologist is an ophthalmologist who has undertaken further specialist training in brain and nervous system disorders that affect the eye and vision.
Signs and Symptoms of Vertigo vary. Dizziness, nausea or problems focusing the eyes or hearing difficulties may be present.
Vertigo is often the result of an inner ear problem. The most common cause is benign paroxysmal positional vertigo (BPPV
Oculomotor muscle fatigue can also contribute.
Meniere’s disease sufferers have a reduced balance response in one of their ears. Electronystagmography (ENG) involves electrodes placed around your eyes to detect eye movement.
As both hot and cold water will cause your balance function and any abnormal involuntary eye movements will be tracked.
Diabetes occurs your blood glucose is too high instead of supplying energy via the hormone insulin to cells.
Type 2 diabetes results from the way the body processes blood sugar (glucose).
Type 1 diabetes is from the pancreas producing little or no insulin.
Prediabetes is where blood sugar is high, but not high enough to be type 2 diabetes.
Gestational diabetes affects pregnant women.
Diabetic Retinopathy The health of the retina is very dependent on a good blood supply to the eye. Diabetes compromises blood circulation and can cause serious damage to the retina.
A stroke can damage the blood vessels that supply the brain and optic nerve, resulting in loss of vision. The nerves that make the eyes move can also be damaged. The type of vision loss depends on the part of the brain affected by stroke. Some people experience blurred vision, double vision or a loss of side (peripheral) vision.
Autism includes a spectrum of conditions such as attention deficit to hyperactive disorder , anxiety or depression. intellectual disability, epilepsy, gastro-intestinal issues, motor learning difficulties, perceptuo-motor dysfunction, and developmental coordination disorder.
Vision problems can include lack of eye contact and controlling central and peripheral vision.
Dyslexia is a genetic brain malfunction in varying degrees that cause difficulty in associating speech sounds to letters and words. A targeted eye examinations can assess the influence from stress from focusing and eye movement control.
It includes diabetic retinopathy, diabetic macular oedema, cataracts and glaucoma.
You can reduce your risk by having your eyes checked as soon as possible after being diagnosed with diabetes. Keeping the diabetes under control is vital, as is eating a balanced diet, getting exercise, not smoking, and monitoring your blood sugar levels, blood pressure and cholesterol levels.Diabetic macular oedema is a form of diabetic retinopathy.It occurs when the swelling involves the macula, which is the part of the retina responsible for central vision. Vision can become blurred and distorted, resulting in trouble reading, recognising faces and driving. Macular oedema (swelling) is the usual cause of vision loss related to diabetes and the level of impairment can be significant. Vision can often be improved by treatment. The three main treatments of diabetic retinopathy are injections into the eye, laser treatment or vitrectomy surgery. Smoking is not a risk factor for diabetic eye damage, but it can damage the eye in other ways. It increases the risk of developing cataracts, blockages of retinal arteries and the wet form of age-related macular degeneration. Diabetics who smoke also increase their risk of heart attack, stroke and kidney failure.
A pterygium is a benign growth and usually harmless. However, in some cases it may harbour cancerous cells. Dusty, sandy and sunny environments (with high UV exposure) are contributing factors.
Eye strain is caused by sub optimal focusing due to optical errors such as long and short sightedness,or astigmatism and binocular coordination difficulties.
Headaches, blurred or double vision can result or discomfort from induced neck and postural strain and the need for more efficient,lighting,blinking and breaks especially for todays digital lifestyle.
The correct ergonomics including correct chair height, adequate equipment spacing and good desk posture and determination of your eye focusing prescription as part of a diagnostic eye examination is important.
A cataract is an opacity or clouding of the lens inside of the eye, behind the pupil that distorts the light as it enters. Quality,contrast and brightness of vision can all be comprimised. Cataract removal is an extremely common operation.
Cataracts are often confused with the whitish triangular pterygia found at 3 or 9oclock usually in front of the pupil
Serious complications are rare with cataract surgery but vision typically fluctuates for about a month post operatively before stabilising.
The protective shield is usually worn for the first day. Cataract surgery does not usually involve stitches.
The success rate is high (98–99%), with around a 1 in 1000 risk of permanently impaired eyesight. Laser cataract surgery costs more than traditional cataract surgery but can reduce complications.
Your surgeon will ensure that your eyelid is gently held open throughout the procedure so that you cannot blink. Some people even fall asleep during the surgery. You are not required to be awake for the operation. During the operation you may see a bit of light and some vague movement or you may see nothing at all.
Spots and 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. spots, floaters.
Sometimes they can be a precursor to a retinal detachment.
The retina is the light sensitive tissue that lines the inside of the rear eye.
The outermost layer is the photoreceptor layer, made up of rods and cones. These cells transform the light energy into electric signals that are processed and then sent to the brain where vision is completed.
The retina acts like the ‘film’ of a camera, sending information about shapes, colours, patterns and movement via the optic nerve to the brain, where the information is processed. If the retina is damaged, this will cause visual disturbances or loss of vision.
The retina is nourished by it’s own blood vessels that feed the inner layers, and by the blood vessels of the choroid, that feed the outer layers of the retina. The macula is the central portion of the retina. Surgery for a detached retina is required to avoid loss of vision and pain.
The retina and optic nerve part of the central nervous system and brain tissue.
Retinal damage, tears or detachment may have symtoms of :
Sudden onset of floaters
Flashes of light in one or both eyes
Blurred vision
Gradual reduction in peripheral (side) vision
Curtain-like shadow over your visual field
Retinal tears and detachments can be repaired with procedures and surgeries such as:
Laser burns around the retinal tear with a sealing scar.
Cryotherapy freezing probe which can also scar and seal
A scleral buckle after a gas bubble is injected into the vitreous space to can push the retinal detachment back into place at the back of the eye.
Glasses to reduce eyestrain for one or several different distances at once are available no matter your optical error such as hyperopia, long sighted, astigmatism for the computer,driving or whatever the situation ,
High index lenses are designed to be thin and light, making them more comfortable for those who require a high prescription lens.
Anti scratch,water repellant,antidust,blue light protective coatings all provide extra features and benefits.
Polarised sunglasses reduce eye strain and eliminate the harsh glare from highly reflective surfaces like snow and water.
Protecting your eyes from UV rays is as important as protecting your skin
Transitions lenses adapt to light as you move from indoors to outdoors.
A blue light coating protects your eyes from blue light emitted from computer screens, smartphones and other digital devices.
An anti-reflective coating removes annoying stray reflections
Bifocal lenses have two areas of prescription for near and distant vision.
Multifocal progressive lenses change gradually from point to point on the lens surface, providing the correct lens power for seeing objects clearly at all distances .
Single vision lenses just have one power set for one viewing distance.
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New prescription glasses require an adjustment period. Optical powers will magnify or minify different directions in space which the brain has to be conditioned to.
Magnifiers can be simple or specialised,providing optical and digital magnification.
A digital magnifier high definition screen allows more flexible working distances that suits each individual compared with optical magnifiers set distances. Coatings and optical quality vary widely.
Glasses that filter blue light and optimally focus digital devices such smartphones and tablets are becoming adopted.
The blue light that’s emitted from these screens,though not damaging to the eyes, can delay the release of the quality sleep-inducing hormone melatonin.
Normally, the pineal gland in the brain begins to release melatonin a couple of hours before bedtime as part of the bodies internal clock circadian rhythms.Some computer apps such as f.lux automatically adjusts the colour and brightness of your screen based on your timezone. When it’s dark outside, it effectively blocks all blue light and gives your monitor a faint orange hue.(warms up the colours on the screen—away from blues and toward reds and yellows)
Blue light damage can effect macular degeneration in susceptible patients.
There is evidence that some kinds of light exposure can cause eye damage under certain conditions. For instance, too much exposure to ultraviolet light from the sun does raise the risks of eye diseases, including cataracts and skin cancer. The electromagnetic fields associated with the use of monitors are not harmful.
Long hours staring at digital screens can cause eye strain, and decreased blinking associated with computer use can cause dry eyes. So it is important to have your eyes examined,focusing checked and good posture and ergonomics practised.
Sit about 50cm (arm’s length) from the computer screen. Position the screen so you are gazing slightly downward.
Reduce screen glare.
Take regular breaks using the 4×20 rule “20-20-20-20” rule: every 20 minutes, shift your eyes to look at an object at least 20 feet away for at least 20 seconds followed by 20 full blinks.
When your eyes feel dry, use artificial tears to refresh them. Adjust your room lighting and try increasing the contrast on your screen to reduce eye strain.
If you wear contact lenses, give your eyes a break by wearing your glasses.
Selection of Personal Protective Equipment (PPE) must take into account the proper wearing and fitting of the equipment just as the case with eyewear We can access the major suppliers
One size does not necessarily fit all – The risks of providing workers with ill-fitting eyewear are significant. Gaps in coverage allow debris to enter the eyes, while slipping and fogging, contribute to worker distraction, loss of productivity, and even the removal of eyewear. That’s why doing fit testing and finding properly fitting eyewear is so crucial to help reduce injuries and increase compliance.
Working with hazardous chemicals can be dangerous. The correct use of chemical gloves is an important aspect of ensuring everyone’s safety in the workplace.
Disposable respirators are only effective when there is a good seal between the edges of the respirator and your face.
If earplugs, whether they be reusable or disposable, are not inserted correctly they will not block the level of noise that they are intended to do.
Antifog Lenses and Antifog wipes are particularly beneficial on high wrap frames that sit very close to your face. Earlier generation anti-fog sprays tend to leave lenses smeary due to silicon build-up.
Normally a microfibre cloth will last around 2 months used every day, before it starts to lose its cleaning ability.
Peeps benefit is its brush which ensures no scratching before you clean them and the cleaning pads are kept in a protective cap between use. For residue that is harsh or more than just fingerprints, use a good quality microfibre cloth and lens cleaning solution, or lens cleaning tissue/wipe.
The difference between Peeps and micro-cloth is that a micro-cloth tends to live in a pocket or case and will attract dust and grip particles over time that potentially can scratch the lenses or worse still with paper towels.
Cracks at the surface of the lens with various patterns and intensities is called crazing can be due to the lenses not having a good quality coating to protect against oils,scratches,waterbeading,fingerprints etc and can be reduced by applying the peeps method.
The benefit of the best quality lens coatings include glare and surface reflection reduction,anti-smudge and antistatic properties. Ease of cleaning and antifogging properties all contribute to why it pays to invest in better quality lenses and coatings.
We can demonstrate Antifog Lenses and Antifog wipes. They are particularly beneficial on high wrap frames that sit very close to your face. Earlier generation anti-fog sprays used to leave lenses smeary due to silicon build-up.
Fog-free vision is achived by spreading fog into a uniform, invisible layer of water on the lens surface.Fog appears with temperature change, always from cold to hot environment with condensing tiny droplets depending upon temperature differences and relative humidity,time of exposure but on a lens with optifog are spread invisibly on the lens surface.
It can happen when stepping out in the cold, or when entering an air-conditioned environment, and it’s most likely to happen during strenuous activity when the body is giving off more heat, and humidity gets trapped behind the lens.
Fog on the front surfaces disperse very quickly . Fog on the back surfaces is worse due to body heat especially if wearing wrap frames.
During extended periods of time under conditions of high humidity, the lens coating may reach its adsorption capacity and lenses may become covered with a thin layer of water or begin to fog. In such cases, wipe with soft cloth will enable normal fog adsorption to be restored.
EN-166 European Standard is the requirement for the time in which lens clarity is maintained under controlled humid conditions.
At least 80% luminous transmittance is required for night driving otherwise AS/NZS1067 requires them to be marked “Not suitable for night driving”.
Generally for driving no tint is recommended.
They can not be too yellow (QBlue must be „0.6 or violet factor „ 0.3) or they need to be marked “Must not be used for driving”. Yellow offers no physical advantages in fog. Yellow sodium streets light is preferred as more lumens per watt results
In fact, most vision and highway safety experts believe that no tint should ever be used at night. The reason for this is that at night the eye needs all the light it can get. While it may be tempting to think that DriveWear’s high contrast yellow green filter might help vision at night, this is simply not the case. While it is true that at 37% transmission and a very high contrast efficient polarizer, DriveWear seems to make the world look brighter, but any reduction in light transmission is highly questionable at night.
On the other hand, there is much justification for putting anti-reflection coatings on clear lenses to make them benefit the driver at night. These coatings are very effective at blocking out the distracting reflections which headlights and overhead lights can produce on the wearers lenses. These reflections are minimized and certainly can help the night driver’s vision and response time.
You should always wear your sunglasses (to Australian Sunglasses Standard specifications) when outdoors during daylight hours. They offer UV protection to lessen cataracts, macular degeneration, pterygium and some cancers.
If contact lenses are left in too long, there is a risk of corneal abrasion and infection. Poor hygiene can leave your cornea vulnerable to bacteria, fungi or parasites. Never reuse your contact lens solution and be sure to always clean the lenses and lens case properly.You should always check the manufacturer’s guidelines or follow your optometrist’s advice regarding how to use and look after your contact lenses.If you experience pain or inflammation, get your eye checked immediately. Always have your contact lenses reviewed regularly by an optometrist.
Bioptic telescopes can help eligible visually impaired individuals sometimes obtain a driver’s license and be safer drivers.
The bioptic telescope eg increases the individual’s ability to see further forward by a factor of the power of the device. For example, a 3x telescope will allow the user to see a sign at 18 metres through their bioptic, while they would only be able to see it at 6 meters feet with their normal vision- 3 times further away.
The Ocutech VES Falcon Bioptic Telescope is the world’s only autofocusing bioptic for the visually impaired.
The right binocular for any use can be found. From a simple monocular that fits in your pocket to twilight binoculars.
The quality of the optics, the types of coatings applied to the lenses, the housing material all vary widely akin to the case in spectacles.
All binoculars are identified by a set of numbers, such as 10×42 and 7×20, which refer to their magnification and objective lens diameter, respectively. Using 10×42 as an example, the 10x means that the binoculars have 10x magnification power, making the view through them appear 10 times closer than it appears to the naked eye.
Contact lenses are an excellent alternative as they are lighter ,resist fogging, offer better peripheral vision and better impact resistance
There is a transparent tissue over the white sclera of the eye called the conjunctiva and also underneath eyelids which prevents that.
Once diagnosed, eye infections usually require intense treatment involving topical antibiotic drops. Drops will usually be required for several weeks, over which time, contact lenses cannot be worn.
The key is early detection and treatment. A contact lens related infection, left untreated for several days, can result in significant corneal scarring and visual impairment.
If your eyes become red or sore whilst wearing lenses, remove the lenses immediately. If the irritation subsides after the lens has been removed then inspect the lens to make sure it hasn’t been inserted inside out or has a rip or tear.
Most eye infections are mild and treatable yet severe infections have the potential to permanently affect vision and in some cases may lead to blindness
Water gradient daily disposable lenses have a thin envelope of water surrounding the core of the lens which prevents the lens from dehydrating and reduces friction between the contact lens and the eyelid when blinking.
Cleaning your hands and then your contact removes surface debris and bacteria that may adhere to your contact lenses. All types of contact lenses should be stored in the appropriate disinfecting solution to avoid infection.
Frequent replacement including daily types have the minimum risk
Tap water contains micro-organisms which can be harmful to the cornea.
Insert your contact lenses prior to applying your make-up and ensure not inside out or mixed up.
Regulary check each eyes vision.
Report for assessment if any increase in redness.pain or blurry vision.
Complications can be reduced by regular after care assessments under the microscope
Do not wear lenses in environments where contamination is likely ie. swimming in rivers.
Wearing time for most contact lenses is around 8-10 hours and should be monitored very carefully with replacement schedules noted and adhered to.
Correct maintenance regimes with fresh storage cases and wear only undertaken with good eye and general health status.
Extended wear contact lenses can be worn continuously for up to 30 days for certain patients under supervision.
The people most susceptible to eye infections are those who sleep in their lenses especially when they’re sick, and those who wear lenses beyond the recommended schedule unaware signs of problems can be detected before the serious symptoms and complications arise.
Whether a contact lens is monthly, fortnightly or daily largely depends on the breathability/oxygen transmissibility of the lens and the thicknesses and comfort for a particular patient.
A contact lens prescription includes many of the material features of newer technology materials that provide high oxygen transmissibility.
The newest generation of cleaning solutions also have wetting agents which improve the wettability of the many types of contact lens surfaces
Poor contact lens fitting and maintenance can cause detrimental long term effects such as corneal scarring and infection
Silicone hydrogel lens materials provide high enough oxygen transmissibility to be safely slept in by suitable patients
Not all contact lens solutions can be used with all contact lenses. Reactions by the sensitive eye tissues to preservatives of solutions and materials need to be assessed under high magnification of an illuminated biomicroscope.
Always establish a consistent routine eg handling the right lens first. Use silicon tweezers and clean cases to reduce contamination risk
Some lens types are marked for orientation often transparent letters and numbers inscribed on the edge of the lens.
The profile of the lens shape will aid in avoiding
an inside out lens from mistaken handling or from the comfort and vision noted if mistakenly inserted
Contact lenses are packaged in sterile blister packs. Always have your insertion and removal technique verified. Hold your eyelids as close to the eyelashes as possible and open the eyes wide to allow the lens to pass through the space between your lids.
The lens will normally center automatically but can sometimes require gentle manipulation with the lids to help center it.
If the eyes feel uncomfortable gently rubbing on your eye through your closed eyelid will often remove bubbles or debris trapped beneath the lens
Often it is recommended that you place a moisturising drop on the lens prior to insertion, which helps cushion the lens when it settles on the eye.
To remove a soft contact lens squeeze the lens lightly between the thumb and index finger. This will allow air underneath the lens to break the suction and allow the lens to be removed.
A hard lens is dislodged by using the lid margins to rotate the lens off by pressing slightly firmer inferiorly.
Dryness of the eye can be a significant problem for many contact lens wearers but can be helped by careful selection of lens material,drops or treatment of dye eye syndrome. The incidence of dry eye increases with age and is more common in women.
Those with chronic eye infections such as blepharitis or meibomian gland dysfunction, computer users, coupled with air-conditioning or dry and dusty environments also exacerbate dry eye.
Squinting in bright light can be reduced by wearing wrap sunglasses and hat. UV damage occurs quickly more in lighter skin
People with lighter eyes and bigger pupils are more prone to squinting by contraction of the circular orbicularis oculi muscle around the eye causes wrinkles and crows feet to develop.
Blue blocking filters can be used to protect the already compromised retina from blue light damage. But blue blockers should not be used for driving by people with colour vision deficiencies. But the advanced RP cases will not be driving.
Tint colour tends to be personal preference. Multicoat technology varies between suppliers
Among the Crizal range:
Crizal UV (also known as Crizal Forte UV) – has no blue blocking effect
front surface – transmits 99.2% of light with a residual bloom in the yellow green range. Remember any UV filtering via the front surface of the lens is solely dependent on the monomer of the base lens e.g. CR 39 only takes out 94% of UV while all of the indices above that take out 100% of the uV
back surface – blocks 96% of the UV reflected by the back surface of the lens with an incident angle of 135 degrees
Crizal Sun UV (applied to the back surface of sunlenses – so there are no multicoat layers on the front)
front surface – any UV filtering via the front surface of the lens is solely dependent on the monomer of the base lens e.g. CR 39 only takes out 94% of UV while all of the indices above that take out 100% of the uV
back surface – blocks 98% of the UV reflected by the back surface of the lens with an incident angle of 135 degrees
Crizal Prevencia:
front surface selectively reflects away 20% of the wavelengths between 400 and 455nm with a peak at 435nm, it allows through at least 98% of the wavelengths around 470 – 490nm in the range of the melanopsin receptors
back surface – as for Crizal UV – the back surface blocks 96% of the UV reflected by the back surface of the lens with an incident angle of 135 degrees
There is also Nikon Seecoat Blue UV the definition of this lens is as follows:
Nikon Seecoat Blue UV
front surface reflects away 5% of the wavelengths between 400 and 500nm with a peak of 10% at 455nm
back surface – as for Crizal UV – the back surface blocks 96% of the UV reflected by the back surface of the lens with an incident angle of 135 degrees.
Prescription glasses can bend light to help it focus on the retina, but they can’t correct any damage in the retina itself.
Today’s replacement lenses can also be used to correct pre-existing vision problems due to short-sightedness, long-sightedness and/or astigmatism. For example, trifocal lenses provide focus at near, intermediate and far distances. These are typically the best option for achieving clear vision without glasses, although there are no guarantees. The most suitable candidates are over 55 years, rely heavily on glasses/contact lenses and are long-sighted. If you are quick to notice visual imperfections, then glasses may remain your best choice
Severe cases may lead to legal blindness, but it’s not typical for a person to become totally blind from this condition. Current treatment options allow people with keratoconus to lead relatively normal lives. Corneal transplantations are reserved for patients who no longer respond to other treatments.
Make sure children wear good-quality, UV-rated, wraparound sunglasses and broad-brimmed hats when they are outside to protect eyes from excessive UV exposure. While this is particularly relevant during sunny weather and other bright, glary conditions (e.g. at the snow), UV exposure can still be high during overcast days.Learn about UV and sun protection times in Australia. Provide a healthy diet with lots of fruit, vegetables and fish.
Get their eyes examined regularly. Always seek prompt medical attention if your child suffers any eye injury or trauma to reduce the risk of complications.
They might tilt their head when looking at something, or they may frequently blink or rub their eyes. A child with vision problems can have difficulty reading or hold a book or screen close to their eyes. Other signs include squinting or having difficulty seeing an object or someone in the distance. Your child may also complain of headaches or blurred vision.
Rayleigh scattering is why the sky is blue
Sunlight reaches Earth’s atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered more than the other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.
The water droplets that make up the cloud are much larger than the molecules of the air and the scattering from them is almost independent of wavelength in the visible range. Mie scattering is why the clouds are white
Optometry involves examining disorders of the visual system and the eyes health. Five universities in Australia offer degrees professional accreditation and a professional entry qualification. Involving up to 7 years of training as well as compulsory CPD every year.
Behavioural optometrists believe that your visual status and the way you interpret what you see is not just dependent on how clear your eyesight is. Consideration must be given to all your visual, visual motor and visual perceptual skills.
Ophthalmologists are also known as eye specialists, eye surgeons and eye doctors. Ophthalmologists can diagnose and treat eye conditions, perform eye surgery, and prescribe medications. A general practitioner or optometrist must refer you to see an ophthalmologist.
Dispensing opticians make and dispense glasses and contact lenses, based on prescriptions written by optometrists.
Bigger bats can see three times better than humans. Bats are key seed dispersers,pollinators and pest controllers
During an eye exam, the patient will sit a specified distance (usually 20 feet or 6 metres) from the eye chart. However, a mirror on the wall is often used as examination rooms are not usually this long. The examiner will ask the patient to start by reading the letters, working down the chart from larger to smaller letter size until they can no longer correctly read the text.
The distance the patient was sitting from the eye chart will be noted against the smallest line they were able to read. This outcome can then be compared to the distance from which the average person reads the same line of letters. The results are then expressed as a fraction, with the patient’s distance on top and the average person’s distance on the bottom (e.g. 20/20 or 6/6).
What does 20/20 vision mean?
Simply put, 20/20 means ‘normal’ distance vision.
In contrast, 20/40 (or 6/12) vision means that a patient who is 20 feet (6 metres) away from a standard eye chart can only read the same-sized letters that someone with 20/20 vision can read from further away (i.e. 40 feet or 12 metres away from the eye chart). In other words, 20/40 vision means you cannot see as well as someone with 20/20 vision.
Nearly 800,000 Australians live with significant vision impairment or blindness, with 90% of these avoidable or preventable cases. Visual impairment can significantly impact a person’s quality of life by affecting daily activities, reducing independence and increasing the risk of falls and injury.
Leading causes of vision impairment globally are due to
Uncorrected refractive errors (short-sightedness, long-sightedness, astigmatism and presbyopia)
Cataracts, and
Age-related macular degeneration
20/20 (or 6/6) vision is a term used to indicate normal visual acuity. However, individual visual acuity can actually be better than this! For example, a person with 20/15 (6/4) vision can, at 20 feet (6 metres), read what the average person can only read when 15 feet (4 metres) away.
Visual acuity refers to the sharpness of images and doesn’t take into account depth perception, colour vision, or the ability to focus on moving objects or read under different lighting conditions. Those with above-average distance vision (better than 20/20 or 6/6) may also have trouble seeing close objects clearly (presbyopia). Presbyopia is a normal condition that occurs with age and generally begins in your mid-to-late forties.
Therefore, it’s possible to have 20/20 vision whilst still requiring glasses for near work.
There is no universally accepted measurement for ‘legally blind’. Different countries, and even different organisations within the same country, adopt varying definitions. Generally, best-corrected visual acuity (that is, vision obtained when using glasses or contact lenses) is used to measure the severity of visual impairment.
The most widely accepted definition, from the ICD-10-AM, defines blindness as having visual acuity worse than 20/400 (3/60).3 Some other organisations, including Vision Australia, are more conservative and class ‘blindness’ as having visual acuity worse than 20/200 (6/60) or field of vision of less than 20 degrees in diameter.
The Austroads eligibility criteria set out the minimum requirements for obtaining a private driver’s licence in Australia, although this may be different under certain conditions (for example, if you require a heavy-duty vehicle licence)
Visual acuity: At least 6/12 in one or both eyes, with or without glasses or corrective lenses
Peripheral vision: Horizontal field of vision of at least 110 degrees. Visual acuity can usually be improved by corrective lenses.
CASA Examinations Civil Aviation Safety Authority (CASA) credentialed Optometrists are trained occupational vision experts, recognised as having particular skills in providing vision care to critical staff in the aviation industry.
Refractive errors (shortsightedness, longsightedness, astigmatism, presbyopia)
interfere with light rays focusing correctly onto the retina. Presbyopia, which is the age-related loss of near vision, is one type of refractive error. It is similar to cataracts in that the lens becomes dysfunctional (it loses its flexibility and becomes stiff). However, unlike cataracts, the lens stays transparent in this case. Presbyopia can be corrected by wearing reading glasses for close-up work.
Some people with presbyopia choose to have a refractive lens exchange (also known as clear lens surgery) but usually lenses are replaced if due to cataracts.
Glasses and contact lenses can improve or correct low visual acuity by adjusting the way light is refracted through the cornea so it focuses correctly on the retina. Depending on your situation and lifestyle needs, options for correcting a corneal refractive error may also include laser eye surgery (LASIK, SMILE or ASLA/PRK) or implantable contact lenses.
Colour vision can be assessed in a comprehensive eye examination.
Colour vision deficiency is the inability to distinguish certain shades of colour eg reds and greens (most common), blues and yellows (less common)
Inherited colour vision defects affect both eyes (due to the common X-linked recessive gene, which is passed from a mother to her son ), whereas a monocular defect can be acquired via pathology. About 8 percent of Caucasian males are born with some degree of color deficiency. Women are typically just carriers of the color-deficient gene, though approximately 0.5 percent of women have color vision deficiency. Pathology that can cause colour vision defects or deficits include:
diabetes
glaucoma
macular degeneration
multiple sclerosis
chronic alcoholism
Medications used heart problems, high blood pressure, infections, nervous disorders, and psychological problems.
Aging.
Chemical Exposure.
Diagnosis occurs after viewing a series of specially designed pictures composed of colored dots, called pseudoisochromatic plates. Further tests are required to assess this provided by an optometrist sometimes in specially equipped colour vision clinics featuring such equipment such as the Nagel anomaloscope, D15 test where hue samples are recorded and referenced in a juxtaposed fashion to a reference and the Farnsworth lantern.Additional testing may be needed to determine the exact nature and degree of color deficiency or colour vision defect.
Early detection of color deficiency is vital since many learning materials rely heavily on color perception.
Several emerging gene therapies have restored colour vision in animal models.
There is no treatment but different techniques to allow colour to be inferred by brightness are being researched and developed.
Achromatopsia is the absence of colour vision,due to problems in the retina or brain. Dyschromatopsia refers to difficulties with colour vision often acquired due to pathologies.
The Ishihara test will only detect Red-Green deficiencies. More than half the acquired deficiencies are Blue-Yellow.
Digital Eye Strain Digital eye strain results from prolonged – and particularly close up – viewing of digital devices including TVs, computers, tablets and smart phones. Dry eyes, blurry vision, headache, and irritated eyes can result.
Digital screens emit blue light as does the sun to a much greater amount. Blue light can influence circadian rhythms which are the bodies internal clock settings that promote sleep or alertnness which is why digital devices should be reduced before sleep time.
Symptoms of computer vision syndrome from eye strain,discomfort,glare,contrast problems and ocular dryness from the associated reduced blinking can be reduced by every 20 minutes looking at something 20 feet away for 20 seconds with 20 firm blinks.
Assesesment for dry eye syndrome should be undertaken as well. Squeezing eyes to close fully is a under utilised blink exercise
Blinking stimulates tear production and gives our eyes a chance to wash away any debris that has accumulated on the surface of the eye ,especially for computer users or dry environments . Concentrated visual tasks include:
Driving
Reading
Watching TV
Screen time includes time watching or interacting with any electronic device – e.g. computers, TVs, mobile phones, tablets and video game consoles. Set acceptable limits for screen time and ensure children take short breaks for at least 5 to 10 minutes every hour. Make sure the room is well lit and reduce glare and reflection from lights or windows.Encourage your child to spend time outdoors every day, even during winter. Australian research shows increasing exposure to outdoor light is a key factor in reducing the risk of becoming short-sighted.
Phorias refer to when the eyes do not align or focus together as a team. This improper control of the eye muscles can sometimes result in crossed-eyes, poor focusing ability, discomfort and headache from the extra effort required. The amount of deviation can be measured by prisms and by a Hess chart for all angles of gaze. The correction is determined by the cause.
Myopia, or short-sightedness, is a condition in which near objects are seen more clearly than objects which are far away
The eyes are more suited to short range rather than long range vision and can be corrected by glasses, contact lenses and surgery such as LASIK.
Accordion Content
Hyperopia or long sightedness, causes a person to see clearer at far distances rather than at near distances
The eyes are more suited to focus long away rather than shorter ranges
Treatment options include glasses, contact lenses and surgery such as LASIK.
The eye focus problem of astigmatism is due to the shape of your cornea and lens
To achieve a point focus the optical correction must occur in specific directions.
Certain eye and brain injuries can cause night blindness. The genetic condition Retinitis Pigmentosa has some cells in the retina not working properly,reducing peripheral vision and causes night blindness.
Sometimes cataract cloudiness distorts and blocks clear eyesight.
Glaucoma can ultimately lead to damage to the optic nerve and loss of vision, including increased night blindness.
Vitamin A deficiency can also cause night blindness. Taking vitamin A as a supplement and getting plenty of vitamin A from natural sources, like leafy greens, helps reduce this problem.
Refractive eye surgery like LASIK surgery may have the unfortunate side effect of causing increased night blindness.
At night, the pupils dilate and whatever vision problems that exist may be increased by this.
If you wear glasses, make sure they are not scratched or cracked. It is worthwhile to filter out short wave lengths to increase the penetration of light in fog but not to reduce the amount of light coming into the eyes at night. It slows reaction time and reduces peripheral vision
Nystagmus can sometimes be improved by surgery or drugs such as Botox or Baclofen
Floaters are particles within the eye that float around like specks or smudges in your field of vision. They occur when the vitreous – the clear, jelly-like fluid that fills your eye – degenerates with age. Floaters can be harmless (e.g. a sign of posterior vitreous detachment). But they may also be a sign of more serious retinal conditions, including retinal detachment and diabetic retinopathy, so make sure you have your eyes checked.
Blind spots and blurred vision are symptoms of many eye conditions. Multiple sclerosis can only be diagnosed after a range of tests. Consult your optometrist or GP if you have any issues with your eyes or vision.
It is possible to assess an infant’s vision, so it recommended that children have a full eye examination with an optometrist at 3 years of age, and then every 2 years as they progress through primary and secondary school. You should also take your child for an eye check if you notice any issues with their eyes or eyesight.
Your doctor or optometrist may decide to refer you to a neuro-ophthalmologist if they suspect a neurological disorder is contributing to your loss of vision or eye problems.
Swelling of the eye can occur even from a mosquito bite. Swelling of just one eye is often due to an insect bite. Mosquito bites are a common cause. It can also be from an irritant (e.g. food) transferred to the eye by the hands.
Suspect mosquito bites if there are bites on other parts of the body. Insect bites of the upper face can cause the eyelid to swell. This can last for a few days. With insect bites, the swelling can be pink as well as large. Large swelling is common for ages 1-5 years.
Swelling of both eyes is usually due to pollen that’s airborne. This includes tree, grass or weed pollen. These pollens float in the air and can travel hundreds of miles. Itching also makes the swelling worse.
Swelling of the face is usually due to allergic reactions to swallowed substances. Examples are foods or medicines. May be part of a severe allergic reaction.
Allergic reactions to antibiotic eyedrops can cause severe swelling of both eyes.
Swollen eyelids from insect bites, pollens or other allergies are itchy.
Swollen eyelids from eyelid infections are painful and tender to the touch.
Mosquitoes are attracted to type O blood ,those with a higher temperature and by a persons particular exhaled carbon dioxide, fragrances and sweat.
By reducing any stagnant water ability for the female to lay eggs will be reduced.
Ponds (stocked with goldfish or koi which will eat the larvae) can attract dragonflies, which can eat mosquitos but a pump or fountain is required to keep the water moving.
Mosquitos are weak flyers and cannot withstand strong breezes, so an outdoor fan can be an effective deterrent as is smoke.
There are many scented plants such as Basil, lemon balm, peppermint, lavender, marigold, rosemary and eucalyptus that can repel them.
Mosquito bites can irritate your skin lead to infection if unduly scratched Give it a light washing with soap and cool water.
Calamine lotion ,soap and cool water can help.
Hydro-cortisone cream, antinflammatories, and antihistamines can counteract the inflammation
Histamines dilate the blood vessels so by cooling the amount of blood is reduced around the bite.
An OTC medication like Benadryl will prevent histamines from binding with receptors at the blood vessels.
A baking soda paste to the mosquito bite can relieve the itch.
Application of local heat to the bite can help destroy the protein that caused the reaction and the itching will stop.
Homeopathic treatments from banana peels to toothpaste, and primrose oil have been suggested to reduce swelling and itching associated with mosquito bites.
In severe cases neck stiffness, headache, nausea and various serious fevers can result.
LASIK, ASLA and SMILE permanently reshape the cornea. Some people may require a follow-up procedure to enhance or improve the initial results. Presbyopia is an age-related condition of your lens, which reduces your ability to focus on near objects and will occur regardless of whether you have laser eye surgery or not.
Laser eye surgery will not prevent the development of presbyopia.
Laser eye surgery is avoided in women who are pregnant. Laser eye surgery isn’t painful and can be used to correct vision by reshaping the eye or effecting tissues for a therapeutic benefit eg reducing pressure inside the eye. The lasers used are very sophisticated and fitted with an infrared eye tracker. This tracker constantly measures your eye movements. Even the smallest movement will be detected, which the laser can compensate for.
Good visual function is achieved within 24–48 hours with LASIK and SMILE and 2–4 weeks following PRK (ASLA) or 1 month after LASIK surgery.
Laser eye surgery is a routine procedure. However, like any surgical procedure, there are always potential benefits and risks.
Minor side-effects are seen in around 1–2% of patients. Sometimes an enhancement be required or temporary dry eyes that require drops can result.
The chance of having a serious vision-threatening complication is extremely small ( less than 1%).
Medicare does not rebate any of the cost of laser eye surgery (apart from some of the cost of the pre-surgical consultation).