WHAT IS VISION LOSS
There are broad spectrums of eye conditions which can lead to vision impairment, many resulting in blindness and permanent vision loss.
Vision impairment is defined as the limitation of actions and functions of the visual system, which places the individual in a position which inhibits their ability to function in the standard manner to that of other human beings.
The U.S. National Eye Institute defines low vision as “a visual impairment not correctable by standard glasses, contact lenses, medication or surgery that interferes with the ability to perform activities of daily living.”
The World Health Organization defines blindness as a visual acuity of less than 3/60 (or equivalent).
Visual acuity is the measure of how well the eyes can see objects from a set distance. For example, 6/60 describes the ability to see objects only at a distance of six metres, while a normal eye can see the same object at 60 metres. Normal visual acuity is 6/6 (20/20 in the imperial measure of feet).
People who are vision impaired include those who are blind, and those who have vision significantly less than normal (which is usually accepted as visual acuity less than 6/18).
Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. This condition is also sometimes called lazy eye.
A cataract is the clouding or opacity of the lens that creates blurred vision. Cataracts affect both distance and near vision and are usually a result of the aging process. They can also develop for other reasons which include congenital causes (from birth) and trauma to the eye. Cataracts that occur as a result of aging usually develop slowly and affect both eyes at different rates.
Surgery to remove the cataract, including the insertion of intraocular lenses, is generally successful. Despite effective and readily available cataract surgery, cataract is still a leading cause of vision impairment.
Diabetic Retinopathy is a complication of diabetes and is the leading cause of blindness in working age Australians. It causes damage to the blood vessels nourishing the retina located at the back of the eye leading to a progressive blurring of vision. Severe vision loss due to Diabetic Retinopathy is sometimes preventable if detected and treated early and appropriately. Treatment may maintain, but not usually restore, vision. Having diabetes also increases the chances of acquiring other vision conditions such as glaucoma or cataracts. It is highly advisable that a person with diabetes should have their eyes examined regularly.
Glaucoma is an eye disease that slowly damages the fine nerves connecting the eye to the brain. The damage generally occurs when pressure within the eye rises. If untreated, glaucoma causes a loss of peripheral vision resulting in tunnel vision and can even result in total blindness. Whilst Glaucoma doesn’t usually develop before the age of 50 years, it affects one in 15 people over the age of 70. Due to its strong hereditary nature, relatives of people with glaucoma should have regular eye examinations.
Age Related Macular Degeneration (AMD) is a degenerative condition affecting the macula, a small area at the centre of the retina. The macula is responsible for fine detailed vision needed for activities such as driving, reading and distinguishing colour. AMD blurs central vision, which affects both distance and near vision. It can lead to partial loss of vision or blind spots appearing in central vision. Fortunately, a person’s side (peripheral) vision remains intact.
Neurological Vision Impairment (NVI)
Neurological Vision Impairment is the term used to describe a vision impairment caused by damage to the brain, such as a stroke (cerebro-vascular accident – CVA), tumour, brain injury or pathological degenerative disease. Vision impairment is generally thought of as damage to or deterioration of the eyes. There are many different areas of the brain that interpret what our eyes see. When these are damaged, the eyes may still function but the message might be misinterpreted or unable to get through to the brain resulting in NVI.
Retinitis Pigmentosa (RP)
Retinitis Pigmentosa is an inherited, degenerative condition that affects the retina – the lightsensitive part of the eye. The retina is made up of millions of light sensitive photoreceptor cells that transmit light via the optic nerve to the brain. RP causes some of these photoreceptor cells to fade gradually and die
thereby losing the ability to transmit the visual message to the brain. People usually start noticing their vision fading in their teenage years.
Good eye health is important for quality of life. Poor eyesight can have a dramatic impact on overall wellbeing and for this reason alone it is essential we don’t take our eye health for granted.
Follow these tips to protect your eyesight:
- Have a regular eye examination. It is recommended to visit your optometrist every 2 years.
- Don't ignore signs and symptoms. Seek help immediately from an eye health professional. Early detection of eye problems is vital and can lead to prevention in most cases.
- Maintain a healthy weight and well-balanced diet. Eating a well-balanced diet controls weight gain and reduces your chance of getting Type 2 Diabetes, which is the leading cause of blindness in adults. Some nutritious foods and nutrients for eye health are: Kale, Spinach, Tuna, Salmon, Beans, Nuts, Eggs, citrus fruits and juices, Broccoli, Brussel Sprouts, Sweet Potato and Carrots.
- Protect your eyes from the sun. Overexposure to the sun can cause permanent damage to our eyes. Sunglasses and UV skin protection are recommended daily even in cloudy weather. Sunglasses should ideally provide 100% UV ray protection.
- Use appropriate eyewear for safety to protect your eyes from workplace hazards and injury.
- Reduce your alcohol consumption. Long term drinking is associated with cataracts, impaired colour vision and other eye diseases.
- Identify your risk factors. Research your family history for any signs of eye disease as there are genetic links for many eye diseases. Early detection of any of these eye diseases, or diseases that cause blindness, will mean early intervention resulting in prevention or minimal long-term vision loss.
Guide Dogs Australia member organisations provide a wide range of services that help people with vision loss to enhance their mobility and independence, and build their confidence for further education, employment and social participation. All our services are provided at no cost to our clients.
By seeking help and support early, you will reduce your risk of falls, accidents and injury. Remember, early detection means early intervention which can result in prevention or minimal long-term vision loss.
Seek emergency assistance if you experience any sudden vision loss or distortion, double vision or pain in your eye.
Contact an optometrist or ophthalmologist if you have difficulties with reading, distinguishing colours or shapes, seeing objects to the side, or if you have any medical condition such as diabetes. You can find your local optometrist and ophthalmologist from these directories:
Guide Dogs organisations across Australia provide a wide range of services that can help you minimise the impact of vision loss and increase your confidence, mobility and independence. To request for services, please contact the Guide Dogs organisation in your state or call 1800 474 333.
- Guide Dogs NSW/ACT
- Guide Dogs Queensland
- Guide Dogs SA/NT
- Guide Dogs Tasmania
- Guide Dogs Victoria
- Guide Dogs WA
For counselling services, contact your local GP who can make a referral.
The following skills provide a practical, comfortable and safe means of guiding a person who is blind or vision impaired. If you are not sure what to do, don’t be afraid to ask. Good communication is the key to being a good guide.
Approach and ask
- Approach the person and introduce yourself.
- Ask the person if they need assistance.
- If the person requires assistance, ask them what kind of assistance they need and how you can assist.
- Speak as you usually would; you don't need to speak loudly or slowly.
- If you're in a group situation, introduce the person to other members of the group.
- Make sure you tell the person when you are leaving.
- Give directions from where the person is located. Use indicators such as right or left, compass points, or clock-face directions. For example, "There is a spare seat three steps to your left" or "Your drink is at two o'clock on the table."
- Initial contact. Touch the back of the person's hand with the back of yours. They would then be able to locate and hold your arm just above your elbow.
- Walking. As a guide, make sure you are half a step in front. This way the person you're guiding is able to pick up on your natural body movements when walking. Walk at a pace comfortable for both of you. Look ahead for obstacles, on the ground, to the sides and at head height.
- Constant and clear communication. Let the person know if you are about to turn or stop, or if there are changes or obstacles on the ground.
- Stairs and kerbs. As a guide, approach the stairs squarely, never at an angle. Stop at the edge and let the person know whether the stairs are going up or down. Suggest changing sides so the person can use the handrail if necessary. As a guide, you need to stay one step ahead of the person you're guiding. Stop when you reach the end of the stairs and indicate their last step.
- Guide Dog follow. A person with a Guide Dog may ask to follow you. Walk on the person's opposite side to the Guide Dog. Walk slightly ahead and talk to person so they can follow your voice. Do not pat or distract the Guide Dog. See more tips on Guide Dog etiquette.
Remember, if you are not sure what to do, don't be afraid to ask the person. Good communication is the key to assisting a person with vision loss.
- It is estimated that there are over 450,000 Australians who are blind or vision impaired.
- Approximately 90% of blindness and vision impairment among Australians is preventable or treatable, if detected early.
- The prevalence of blindness and vision impairment in Indigenous Australians is three times that of non-Indigenous Australians.
- Half of Australians are at a higher risk of losing their vision due to a family history of potentially blinding eye conditions.
- 9 out of 10 Australians say that sight is their most valued sense, yet 28% of Australians do not get their eyes tested regularly.