Vision/Low Vision Flashcards
Best-corrected visual acuity less than 6/12 (<20/40) in the better seeing eye
Low Vision
20/30 to 20/60
Mild vision loss or Near-normal vision
20/70 to 20/160
Moderate visual impairment or moderate low vision
20/200 or worse
Severe visual impairment or severe low vision
<20/1000
Profound visual impairment or near-total low vision
No light perception
total visual impairment or total blindness
Ability to see small visual details, ensuring that precise visual info is provided to the CNS
Visual acuity
Difficulty focusing on NEAR objects, common in age related change in adults over 50
Presbyopia
Nearsightedness, is a normal deficiency in visual acuity in which near objects are seen more clearly than distant objects
Myopia
Farsightedness, is a normal deficiency in visual acuity in which distant objects are seen more clearly than near objects
Hyperopia
Ability to perceive and detect objects in relationship to the background of their environment, ability to see shades of color, essential to negotiating environments safely
Contrast sensitivity
Scope of vision in each eye. Provides background info about one’s position in relationship to the environment and is quick to detect motion
Peripheral visual field
The central 20 degree of vision
Central Visual Field
Ability to move eyes smoothly and in coordinated manner through full ROM.
Oculomotor Control
Ensuring one object is seen even though 2 images are being provided to CNS
Binocular Vision
Ability to adjust focus of vision at different distances. Can be affected by normal aging caused by presbyopia
Accommodation
Muscle action of eyes that moves them inward (adduction) to allow focusing on nearby objects
Convergence
Causes the perception of two images of a single object. Pt may assume head position or tilt to eliminate
Diplopia
Ability to identify specific features of an object and ignore other irrelevant sensory info
Visual Attention
Occurs when visual search patterns are confined to one side of the visual array in which client misses info on the other side
Hemi-inattention
General functional impairments in visual related to aging
(1) Ability to see close objects and coordinate the eyes decrease
(2) Images becomes blurrier
(3) Ability to see at night decreases
(4) Eyes adapt more slowly to changes in lighting conditions
(5) Contrast sensitivity decreases
(6) Ability to view objects in low light decreases
(7) Ability to distinguish certain colors diminishes
(8) Visual field becomes narrow
Affects the central portion of eye that provides fine detail for near-distance activities like reading
Objects appear distorted in shape, straight lines appear wavy
Age-related Macular Degeneration
Cause loss of peripheral vision
Glaucoma
Fluctuating vision, including blurred vision and peripheral vision loss
Decrease contrast sensitivity and difficulty identifying low-contrast items
Diabetic Retinopathy
