Low Vision Flashcards
What is low vision
Can not be corrected by medical/surgical intervention, glasses, or contacts
Has an ability to complete functional activities independently
Legal Blindness
20/200 or worse in better eye or a visual field of 20 degrees or less in better eye
Legally blind individuals have a large amount of fx’l vision remaining.
Some people w/ 20/800 can still continue to participate in ADL’s w/ specialized adaptive equipment.
Low Vision Stats (1)
3 million people have some form of low vision
The number is expected to double in the next 25 years
Pt.’s with visual impairment had an ALOS 2.4 days longer than that of pt.’s with no visual impairment.
Low Vision Stats Continued (2)
48% of individuals in nursing homes have a visual impairment
86.5 of veterans responding to a survey reported that receives a great deal of benefit from using optical devices-> most common tasks included reading, med management, reading, checking telephone #’s
Low Vision Stats Continued (3)
2/3 of older people w/ vision impairments have at least one other chronic condition that limits their mobility of independent functioning
A decline in visual stats is associated with lower emotional, physical, and social function.
85% of those who are visually impaired have some usable vision and can benefit from vision rehab
Macular Degeneration
*Leading cause of legal blindness in people over the age of 60
Causes damage to the macula.
Maculs is responsible for capturing & directing light, seeing detail, color, CENTRAL VISION
Dry Macular Degeneration
Light sensitive cells slowly break down causing gradual blurring of the central vision in the affected eye.
Most common form of macular degeneration
Wet Macular Degeneration
Abnormal blood vessels grow under the macula that leak blood and fluid causing rapid damage to the macula
Causes of Macular Degeneration
Smoking, obesity, race (whites more than blacks)
Family history, gender (women are at greater risk)
Macular Degeneration : Functional Implications
Decreased ability to perform “straight ahead” activities (reading, sewing, driving)
Early sx. include straight lines appearing curvy
Sx. of Charles Bonet Syndrome- seeing images that aren’t there (stars,flowers)
Detailed vision is reduced and a person may have trouble seeing up close or at a distance
Decreased ability to judge height, distance, and depth
Macular Degeneration : Treatment
Environmental modifications Magnification Don't smoke, diet & exercise Medication/vitamins Laser surgery (wet) Photodynamic Therapy (wet) Mantain good Bp Clinical trials
Glaucoma
Approximatley 5,500 more people became legally blind each year as a consequence of glaucoma
The “sneak-thief” of vision
#1 cause of preventable blindness
Glaucoma : Causes
Age 60+
Family history
Blacks (40 +)
Diabetic pt.’s
Glaucoma : Functional Implications
Decreased peripheral vision Sensitivity to light Blurred, misty, or foggy vision Pain (anywhere from forehead to cheeks) "Halo" around lights
Glaucoma : Treatment
Any damage is permanent; tx. can only prevent the disease from progressing Medication - eye drops and oral meds Laser Surgery - installing a safety valve Environmental Modifications Regular check-ups
Cataracts
Clouding of the normally clear lens of the eye
The purpose of the lens to bend light rays to provide a clear image of the retina on the back on the eye.
Clouding of the lens leads to a distortion of light passing through the eye.
Progression of cataracts can vary in each individual, and each eye.
Cataracts : Causes
Disturbance of metabolism in the lens
Effects of ultraviolet light
Cigarette smoking
Cataracts : Functional Implications
Blurred vision Decreased sensitivity to light Sensitive to glare Bright lights are uncomfortable Difficulty identifying color Decreased contrast resulting in objects appearing dull
Cataracts : Treatment
Change in glasses may benefit Cataract surgery Increase/change lighting Absorptive lenses Magnifiers, large print materials Use of a hat on sunny days Use bright colors with high contrast Adjust shades to reduce direct light/glare
Diabetic Retinopathy
80% of diabetics have diabetic retinopathy
40% of diabetics have retinopathy after 5 years of onset
Diabetic pts. are at in increased risk for cataracts & glaucoma
Diabetic Retinopathy : Causes
Diabetes Obesity Family Hx Diet Lifestyle
Diabetic Retinopathy : Functional Implications
Decreased visual acuity Increase in glare Central & Peripheral vision affected Overall Blurred/Hazy vision Trouble seeing detail (faces, print, TV) ("swiss cheese effect")
Diabetic Retinopathy : Treatment
If untreated can result in blindness Prevention is best tx Routine retinal exam to monitor effect of the disease Test blood sugar 3-4 times per day Maintain diet and exercise Environmental Modifications Magnification Laser surgery -slows or stops disease Vitrecotomy - used when no other option is available (removal of blood, scar tissue, & viterous)
Rehab & Medical Model
The opthamlmologist and or optometrist and OT work as a team in the eval process
Team approach