Vision impairment, also known as visual impairment or vision loss, is a decreased ability to see to a degree that causes problems not fixable by usual means, such as glasses. Some also include those who have a decreased ability to see because they do not have access to glasses or contact lenses.
Visual impairment is often defined as a best corrected visual acuity of worse than either 20/40 or 20/60. The term blindness is used for complete or nearly complete vision loss. Vision impairment may cause people difficulties with normal daily activities such as driving, reading, socialising, and walking.
The most common causes of visual impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%). Refractive errors include near sighted, far sighted, presbyopia, and astigmatism. Cataracts are the most common cause of blindness. Other disorders that may cause visual problems include age related macular degeneration, diabetic retinopathy, corneal clouding, childhood blindness, and a number of infections. Visual impairment can also be caused by problems in the brain due to stroke, prematurity, or trauma among others. These cases are known as cortical visual impairment. Screening for vision problems in children may improve future vision and educational achievement. Screening adults may also be beneficial. Diagnosis is by an eye exam.
Source: Source: Wikipedia
Vision loss in Australia
Visual impairment and its causes are strongly related to age. Prevalence rates for both visual impairment and blindness are markedly greater among older age groups as are rates of major sight-threatening eye conditions. With the ageing of the population, the number of older people with vision problems will increase over future decades, if prevalence rates remain constant.
Among Australians aged 40 and older in 2009, the major causes of vision impairment were age-related macular degeneration (AMD), cataracts, diabetic retinopathy, and glaucoma.The major causes of blindness are AMD.
AMD affects around 500,000 Australians of whom 100,000 have significant vision loss.4 In the absence of treatment and prevention efforts, the number of people with late stage macular degeneration disease (vision loss) could double from 167,000 to 330,000 by the year 2030.
In 2010, the total economic cost of vision loss associated with AMD was in excess of $5 billion. This includes health system costs, other costs to individuals and community, and loss of wellbeing. For every $1 invested in the current treatment for wet AMD, there has been a $2 saving in social benefit costs.
Vision loss - is it preventable?
The World Health Organisation estimates that 80% of visual impairment is either preventable or curable with treatment. This includes cataracts, the infections river blindness and trachoma, glaucoma, diabetic retinopathy, uncorrected refractive errors, and some cases of childhood blindness. Many people with significant visual impairment benefit from vision rehabilitation, changes in their environmental, and assistive devices.
It is estimated that half of visual impairment and blindness can be prevented through early diagnosis and timely treatment. Despite cost-effective treatment and eye preservation interventions, the number of potentially blinding eye diseases continues to escalate. Increased awareness can help - remind family members and friends at higher risk for eye diseases and vision loss to have their eyes examined regularly.
Detecting signs of low vision
Below are some signs of low vision. Even when wearing your glasses or contact lenses, do you still have difficulty with:
- Recognising the faces of family and friends?
- Reading, cooking, sewing, or fixing things around the house?
- Selecting and matching the color of your clothes?
- Seeing clearly with the lights on or feeling like they are dimmer than normal?
- Reading traffic signs or the names of stores?
These could all be early warning signs of vision loss or eye disease. The sooner vision loss or eye disease is detected by an eye care professional, the greater your chances of keeping your remaining vision. Early detection can save your eye sight.
Impact of vision loss
Visual impairment can diminish the health and wellbeing of older people in many ways, for example by affecting their mobility and contributing to their risk of falls and injury. Their ability to perform everyday activities such as reading or watching television can be affected, as can their ability to drive and to interact socially. Visual impairment can significantly reduce quality of life and contribute to depression in older people. Preventing and treating visual impairment can increase the prospect of enjoying life as a healthy, productive older person.
Depression rates amongst carers aged 65 years and older of someone with wet AMD are more than triple those in the general population while carers aged under 70 report even higher rates of depression, with one in nine suffering from the condition.
The facts on vision impairment and loss
In Australia in 2009 the total cost of all vision loss including uncorrected refractive error was $16.6 billion, a cost of $16,360 per person aged over 40. Loss of well-being was responsible for 57 per cent of costs, with health system and productivity costs contributing 18 and 14 per cent respectively.
Lack of national services
Australia has no national services for people 65 and older who are blind or vision impaired. In spite of exciting advances in treatment such as bionic eye implants, nanosecond lasers and vision regeneration, older Australians continue to miss out on integrated models of care and prevention that could halt or reduce their vision loss.
Older Australians with severe vision loss face significant out of pocket costs for specialists, allied health services and technologies. In contrast, the Hearing Services Program provides free testing and hearing aids for concession card holders and Australians aged under 65 years with vision loss are supported through disability packages.
Inconsistent access to support and services
Inconsistent access to Home and Community Care (HACC) and Home Care services and technologies leave many older Australians unable to access visual supports, in spite of significant improvements in daily activities and functions associated with their use. Although non-government organisations attempt to fill this void, most require co-contributions and are unable to meet all requests for assistance.
Reading, vision and orientation technologies such as computer screen scanners, text readers, smart phones and tablets are expensive for people on fixed incomes, including pensioners. However the use of such technologies delivers cost-effective benefits for independent living and reduces health co-morbidities.
Subsidised assistive technologies are urgently required; for people at risk of, and living with, severe vision loss.
Sources: AIHW, National Seniors