Visual Impairment Flashcards
1
Q
Quality of vision is referred to in terms of what?
A
- acuity and field
2
Q
What does the 20/20 method measure?
A
- visual acuity of eye
3
Q
What is field of vision?
A
- area within which objects can be seen when eyes are fixed straight ahead
4
Q
What is visual impairment/vision loss?
A
- refers to a range of visual ability - legal blindness,
partially sighted, totally blind
5
Q
What is legal blindness?
A
- 20/200 in the better eye even with the best
correction - 200 FOV
6
Q
What does it mean to be partially sighted?
A
- can make out shapes and object
7
Q
What is the average age for someone with a visual impairment?
A
- 40
8
Q
What percentage of Canadians will experience vision loss after the age of 65?
A
- 1/9
9
Q
What percentage of Canadians will experience vision loss after the age of 80?
A
- 1/4
10
Q
What are some common causes of vision loss in children?
A
- congenital cataracts, optic nerve disease, retinopathy of prematurity
11
Q
What are some common causes of vision loss in adults?
A
- cataracts, macular degeneration, diabetes
12
Q
What is the retina?
A
- inner lining of eyeball
- expansion of optic nerve
- sensory receptors for light
- tissue which lines the inside of the eye and sends visual images to the brain
13
Q
What are three conditions of the retina to be aware of?
A
- detachment, pigmentosa & glaucoma
14
Q
What is retinal detachment?
A
- retina separates from back of the eye and detaches causing blurry or blind spot in field of vision
- as cells die vision is lost
15
Q
Why does the retina detach?
A
- detaches because of small tares or holes
- fluid may seep through the small tares and flow between back wall of eye and the retina
- eye diseases,
complications of diabetes and or tumours - avoid activities that will jar the head
16
Q
What is retinal pigmentosa?
A
- inherited
- slow but progressive degeneration of retinal cells causing loss of vision (light sensing cells)
- restricts vision field, causes tunnel vision and
night blindness - avoid low light activities
17
Q
What is glaucoma?
A
- increased pressure inside of the eyeball damages optic nerve
- affects peripheral vision and with time can affect central vision and can result in complete loss of vision
- avoid activities that include increased eye pressure (swimming)
18
Q
What is retinopathy of prematurity?
A
- abnormal growth of blood vessels within the retina and vitreous that occurs in some premature infants
- nutrients are not delivered to the retina properly
- blood vessels are fragile and prone to leak
19
Q
What can later stages of retinopathy of prematurity lead to?
A
- can lead to the formation of scar tissue on the retina, vitreous hemorrhage, and retinal detachment
20
Q
How can ROP damage the brain?
A
- oxygen is poorly circulated/regulated in the incubator and too much oxygen damages the retina, may cause mild damage to the brain
21
Q
What is cataracts?
A
- clouding of the lens of the eye
- may affect just a small part of the lens, or it may cloud the entire lens
22
Q
What does the lens of the eye do?
A
- located near the front of the eye
- focuses light on the retina, to form the images we see
23
Q
What can cause changes in the medical makeup of the lens?
A
- aging, certain medications (e.g. steroids), genetics, eye injuries, or certain diseases can cause cataracts
24
Q
Can children get cataracts?
A
- yes, congenital cataracts
- inherited, or cause by an eye infection before birth?
25
What are some causes of cataracts?
- caused by a change in the chemical makeup of the lens
| - eye injuries, such as a hard blow, puncture, cut, intense heat, or chemical burn can damage the lens, diabetes
26
What is diabetic retinopathy?
- change in blood vessels that feed retina
| - vessels can either dry up and prevent nutrients from reaching retina or they can leak and ‘flood’ the area
27
How many diabetics get diabetic retinopathy?
- 1/4
28
What is proliferative diabetic retinopathy?
- as the disease advances, blood vessels become blocked or closed and parts of retina die
- new blood vessels grow, abnormally, and tend to bleed into eyes, blocking vision
- scar tissue forms, retina tears, and retina can detach itself from the back of the eye
29
How can retinopathy be treated?
- lasers seal leaky vessels, stop growth of new ones
30
What is macular degeneration?
- most common cause of severe vision loss in Canada, esp. among elderly
- blurred central vision
- macula can become distorted or thin, or abnormal blood vessels develop and leak fluid and blood under macula, into retina
31
How can vision impairment affect development?
- motor development and performance is often delayed in infants who have a visual impairment
- lack of play and social skills
32
How can visual impairment affect physical activity?
- can be difficult to teach movement patterns
- lowered fitness than sighted peers
- mechanical inefficiency in gait in unfamiliar areas
33
What are some considerations for physical activity opportunities?
- brightly coloured & auditory equipment
- make distinction between surfaces to indicate out of bounds
- braille on swimming pool walls
- guidewires
- difficulty with spatial awareness and body image
34
What are some considerations for movement?
- walking in a straight line; making turns
- facing sounds, people
- find starting point after a short walk
- relate direction to sunshine
35
What are some considerations for sound usage?
- bouncing objects
- catch bouncing object
- follow a voice
- jump rope
36
What are some considerations for orientation and mobility training?
- demonstrate/talk about how to play
- pump legs while swinging
- jungle gym
- teeter-totter with friends
37
What are some considerations for safety?
- orientation (landmarks, anchor points)
| - consistent, clutter–free area
38
What are some considerations for communication?
- descriptive language
- brailling or hand-body manipulation
- augmented sensory information (beeper balls,
bright colour strip on badminton net etc.)
- ‘buddies’
- use residual vision – large print, contrasting colours
39
How can you guide and describe?
- person with VI holds the back of your arm above elbow
- walk side by side
- verbal indications of steps (up or down)
- change in surface (incline, decline, hole)
- doors (push or pull open)
