SCOA: Vision Loss

Vision loss becomes more common as people grow older, as does the incidence of certain diseases that cause vision loss.
Eye diseases that cause blindness include cataracts, age-related macular degeneration, glaucoma, and diabetic retinopathy.
Older people should get an eye examination annually to check for eye problems and reduce the effects of vision loss.

Vision loss is not a normal part of aging. Normal age-related vision change include losing focus (presbyopia), declining colour perception and contrast sensitivity, needing more light to see well, and needing more time to adjust to changing light levels.
Vision loss – visual acuity less than 20/40 – affects 20% to 30% of people over the age of 75 years.
Severe vision loss and blindness (visual acuity less than 20/200) typically results from eye diseases such as cataracts, age-related macular degeneration (ARMD), diabetic retinopathy, and glaucoma.
Severe vision loss affects quality of life, independence, mental health, and life satisfaction, and creates difficulty with activities of daily living. It is also a risk factor for falls and accidents.
It is estimated that 40% of blindness is either preventable or treatable by prompt diagnosis, treatment, and proper management of diseases like diabetes.
By visiting an eye care professional regularly, chances are increased for receiving a diagnosis if eye disease is present. The earlier the diagnosis, the greater the opportunity to minimize vision loss.
You can help to avoid vision loss by making simple lifestyle changes like wearing UV-protective sunglasses all year round, taking vitamins, quitting smoking, exercising regularly, controlling diabetes and maintaining a healthy diet high in omega-3 fatty acids and dark, leafy greens.

The following images show how various conditions affect what a person can see.

Normal Vision	Age-Related Macular Degeneration

Cataracts	Glaucoma

Diabetic Retinopathy

ARMD is the leading cause of vision loss in Canada.
In ARMD, the central area of the retina (macula) degenerates causing central vision loss. There are two forms of ARMD:

Symptoms of ARMD include loss of central vision, visual distortion, and loss of colour discrimination.
Causes are not well understood. Risk factors of ARMD include genetics, light skin or eye colour, sun exposure, farsightedness, smoking, hypertension, and poor diet.
The cause and cure for AMD are unknown. However treatments are available in a small percentage of cases.
For advanced dry ARMD, oral vitamins that contain vitamin E, C, and zinc. Treatment of wet ARMD includes thermal laser therapy, photodynamic laser therapy, and the injection of drugs directly into the eye to reduce new blood vessel formation.

Cataracts are a clouding of the lens of the eye. The lense becomes as cloudy as a frosted window. This clouding reduces the amount of light passing through the lens and focus on the back of the eye (retina).
Symptoms of cataracts include sensitivity to glare, trouble distinguising colour, , hazy/cloudy vision, streaking, halos, double vision, and decreased night and distant vision.
Risk factors for cataracts include age, trauma, certain drugs (steroids), light (ultraviolet B) exposure, smoking, diabetes, alcohol use, and a diet deficient in anti-oxidants.
When cataracts become so severe that they affect activities of daily living, surgery is required. An operation removes the affected lens and replaces it with an artificial lens.

DR is a disease in which changes occur in the tiny blood vessels that nourish the retina.
Diabetic retinopathy is a complication of advanced diabetes.
DR often has no early symptoms. A person may see specks of blood, experience blurred vision, or near vision distortion (difficulty reading)
Not everyone with diabetes develops retinopathy, which is why dietary control (low blood glucose) and exercise are so important.
In early stages of retinal bleeding, laser treatment of localized areas of leakage can stabilize vision. If bleeding is severe,a vitrectomy may be necessary, where blood and gel are removed from the centre of the eye and replaced with a salt solution.

Glaucoma is a disease that causes damage to the optic nerve, usually resulting from a build-up of fluid pressure inside the eye, causing gradual loss of peripheral, or side, vision.
Glaucoma can have few symptoms until the disease is advanced. Some warning signs include subtle loss of contrast, difficulty driving at night and loss of peripheral vision (late-stage glaucoma)
Risk factors include age, increased fluid pressure within the eye, family history of glaucoma, being Afro-American, near-sightedness, use of cortisone (steroid) drops, and systemic diseases such as diabetes and hypertension.
Medical treatment includes eye drops to increase the drainage of fluid or to decrease the production of fluid in the eye. Surgery is needed if the eye pressure needs to be reduced urgently.

The Canadian Association of Optometrists recommends

Healthy adults who do not notice anything wrong with their eyes should see an eye doctor according to this schedule:

An eye exam at age 40 is recommended in order to screen for eye diseases and to obtain a baseline against which vision can be later compared.

You should seek medical attention immediately in the following circumstances:

loss of vision or decreased vision in one or both eyes
changes in vision such as sudden spots, flashes of light, jagged lines of light, wavy or watery vision, blurry faces, distortions or wavy lines, haloes around lights, double vision
changes in the field of vision such as shadows, curtain-like loss of vision, black spots or blurriness in central or peripheral (side) vision
changes in colour vision
painful eye
redness, itching, burning, or discharge from the eye
sudden changes of the eyelid

Older people with vision loss are prone to falls and injuries. Here are some things that can help with prevention:

Encourage open and honest communication, and assure your loved one that s/he is not a nuisance.
Using one’s remaining vision will not cause further deterioration of an eye condition; it will train the brain to interpret images more readily.
One of your main objectives is to help maintain the independence and dignity of your loved one.
The best question to ask yourself is, “What can I do to help?

Canadian National Institute for the Blind

Main Website: The CNIB is a national voluntary agency providing services to individuals across Canada to whom loss of vision is a central problem in personal and social adjustment.

Vision Problems and Your Age: This slide show explores common vision problems and more-serious eye disorders in older adults. It also discusses ways to protect your eyes and prevent vision problems.

Eye Conditions, Disorders and Treatments provides links to patient information pamphlets.

Health Canada

It's Your Health: Seniors and Aging – Vision Care: Health Canada provides this overview of conditions and steps that people can take to preserve their eyesight and remain independent.

This is the main information page for 'Eyes and Vision', which contains an extensive and comprehensive list of links to relevant resources.

Last modified: Wednesday, 27 April 2022, 9:33 AM