Eye Condition Flashcards
describe each eye condition, stability, VA, refractive error; VF, contrast sensitivity, preferred task and ambient lighting; accommodation
ACHROMOTOPSIA (ROD MONOCHROMACY)
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
a congenital defect in or absence of CONES
results in inability to see color and reduced clear central vision
stable
VA: 20/100 to 20/200
astigmatism
normal VF
reduced contrast sensitivity
dim task lighting; very high sensitivity to ambient light
no color vision; name some colors by brightness
accommod. varies by age
ALBINISM
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
Ocular: congenital absence of pigment in iris & choroid
Oculocutaneous: congenital lack of pigment in iris, choroid, hair and skin.
Causes light sensitivity, nystagmus & reduced VA
stable
VA: 20/60 to 20/400
astigmatism
normal VF, contrast sensitivity & color vision
task lighting: dim to intermediate;
high to very high sensitivity to ambient light
accommod. varies by age
ANIRIDIA
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
congenital malformation of iris that can be accompanied by nystagmus, photophobia, reduced VA and often glaucoma
cataract & glaucoma may develop
20/200 to 20/400
astigmatism
VF normal unless glaucoma
reduced contrast sensitivity
task lighting: dim to intermed.
ambient lighting: high to very high sensitivity
normal color vision
reduced accommod.
COLOBOMA
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
notches or other defects caused by improper fusion of tissue during gestation; may affect the iris, lens, retina, choroid, ciliary body, eyelid and/or optic nerve
usually stable; retinal complicatns may develop
20 / 20 to 20/400
refractive error varies
VF: depends upon retinal area involved; superior most common
contrast sensitivity, preferred and ambient task lighting and accommod. vary
normal color vision
CONGENITAL CATARACT (w. cataract removal)
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
aphakia (lens removed surgically), deprivation amblyopia / lazy eye, nystagmus may or may not be present
glaucoma may develop
VA: 20/40 to 20/400
high hyperopia
normal VF (unless adv. glaucoma)
reduced contrast sensitivity
preferred task lighting varies
moderate sensitivity to ambient light
normal color vision
no accommodatn bcuz cataract isremoved
CORTICAL VISUAL IMPAIRMENT /
CEREBRAL VISUAL IMPAIRMENT
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
dysfunction of posterior visual pathway and/or occipital lobe;, usually accompanied by other neurological disorders
can improve at an early age; variable visual functioning
VA: varies
refractive error varies
VF: nearly always reduced
contrast sensitivity: reduced
preferred task lighting varies
sensitivity to ambient lighting: high in about 1/3 of cases
may prefer primary colors
accommod. varies w/ age
DELAYED VISUAL MATURATION
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
brain dysfunction assoc. w/ varying causes
improves by 8 mos of age in most children
VA, refractive error, VF: varies
reduced contrast sensitivity
task lighting, sensitivity to ambient lighting, color vision and accommod. vary
DIABETIC RETINOPATHY
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
abnormal retinal swelling and/or new blood vessel growth; glaucoma may develop
laser treatment or surgery may stabilize
20/20 to NLP
refractive error: variable is sugar levels not regulated
VF: depends upon retinal damage
contrast sensitivity & color vision: reduced
preferred task lighting & ambient lighting: moderate
accommodation: reduced
GLAUCOMA
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
optic nerve atrophy due to elevated IOP, insufficient blood flow
often stabilized or slowed with treatment
VA: reduced in adv. cases
myopia more common
VF: mid and then far peripheral, can be central
contrast sensitivity & color vision are reduced
preferred task lighting & ambient lighting: moderate
accommod. varies with age
KERTACONUS
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
thinning and distortion of cornea w/ possible scarring
slowly progressive, may require surgery
20/20 to 20/60 w/ contact lenses
contact lenses usually required
VF and color vision: normal
contrast sensitivy reduced
preferred task lighting and sensitivity to ambient lighting varies
accommod. varies with age
MACULAR DEGENERATION
incl age-related, myopic, juvenile, Stargardt’s disease, histoplasmosis (fungal disease) and toxoplasmosis
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
deterioration of central vision caused by a degeneration of the central retina
usually progressive for several years
20/25 to 20/1000
refractive error varies
central scotomas
contrast sensitivity and color vision are reduced
prefer bright task lighting; sensitivity to ambient lighting is high
accommod. varies with age
MACULAR HOLES
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
photoreceptor layers pulled away from center of macula
stable: surgery may be possible in early stages
20/40 to 20/400
refractive error varies
small, central scotomas
reduced contrast sensitivity
preferred task lighting & sensitivity to ambient lighting: moderate
normal color vision
accommod. varies with age
MARFAN’S SYNDROME
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
connective tissue disorder causes crystalline lens to loosen
possib glaucoma; lens position may vary
VA: near normal
high myopia
VF, contrast sensitivity and color vision normal
preferred task lighting and sensitivity to task lighting moderate
reduced accommod
NYSTAGMUS (congenital)
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
involuntary movement of they eye, usually rhythmical and faster in one direction than other; horiz or vert
stable
20/20 to 20/120
refractive error and accommod vary
everything normal
OPTIC ATROPHY
definition
stability
VA
refractive error
VF
contrast sensitivity
task and ambient lighting
color vision
accommodation
optic nerve atrophy; nystagmus may be present
usually stable
20/80 to 20/2000
refractive error, VF and accommod vary
reduced contrast sensitivity and color vision
moderate task lighting and sensitivity to ambient lighting
