Low vision Flashcards
Low vision is defined as
uncorrectable “loss of visual function . . . resulting in a loss of functional ability and quality of life”
The sclera is
the white outermost layer of the eye it protects and maintains its shape.
The iris is a
colored structure that works like the lens of a camera, allowing images into the eye by controlling how much light passes through the pupil, and is covered by the cornea
What is the cornea?
clear protective film over the eye that allows and focuses light into the iris.
What sits behind the iris? What does it do?
the lens, helps focus the image on the retina
What is the retina?
the innermost layer of the eye, which contains nerve cells that receive and transmit the image through the optic nerve to the brain.
Current classification of low vision is based on deficits in
visual acuity (i.e., degree to which a person can see) and visual field (i.e., amount of space visible without moving the eyes)
The following are the four most common eye diseases in older adults:
- Macular degeneration: damage to the macula causing decreased central vision
- Cataracts: increased opacity in the lens that causes blurring of vision
- Glaucoma: pressure in the eyeball causing a loss of peripheral visual field and eventually blindness, if not controlled
- Diabetic retinopathy: primary complication of diabetes that causes severe and progressive blurring due to leaking of blood vessels in the retina (Klein & Klein, 2013 Sternberg, 2013)
Macular degeneration:
damage to the macula causing decreased central vision
Cataracts:
increased opacity in the lens that causes blurring of vision
Glaucoma:
pressure in the eyeball causing a loss of peripheral visual field and eventually blindness, if not controlled
normal vision
20/12–20/25
definition of low vision
Condition caused by eye disease, in which visual acuity is 20/70 or poorer in the better-seeing eye and cannot be corrected or improved with regular eyeglasses
Legal blindness
20/200 or less in better eye
OR
a visual field of 20 degrees or less in better eye
OR
a visual field (total area a person can see without moving the eyes from side to side) of 20 degrees or less (tunnel vision) in the better-seeing eye.
Blank spots or distortions in central vision
scotoma associated with macular degeneration
Charles Bonet Syndrome -
seeing images of objects not there (flowers or stars) associated with macular degeneration.
ways to manage macular degeneration
Lifestyle management
Environmental modifications
Magnification
Medication / vitamins
Laser surgery
Maintain good blood pressure
what eye disease often has no signs but is preventable if a doctor looks yearly
glaucoma
symptoms of macular degeneration
Decreased ability to perform “straight ahead” activities such as reading, sewing, and driving
Early symptoms include straight lines appearing wavy
Difficulty recognizing faces
Symptoms of Charles Bonet Syndrome -seeing images of objects not there (flowers or stars)
Detailed vision is reduced and up close or distance work is challenging
Blank spots or distortions in central vision /scotoma
Decreased ability to judge height, distance, and depth
Diabetic retinopathy
primary complication of diabetes that causes severe and progressive blurring due to leaking of blood vessels in the retina. Will lead to blindness
C5:
Elbow flexors
C6:
Wrist extensors
C7:
Elbow extensors
C8:
Finger flexors
