Glossary of Eye Conditions on Such A Site
The following massive list is from the American Foundation of the Blind’s Website. They state this may be shared and that is the list I am sharing below. It is a list of all the Eye Conditions which Might Cause a person to have Low Vision.
A
Achromatopsia
Rare, inherited vision disorder in which a person has little or
no ability to see color. People with achromatopsia also commonly experience some
vision loss, especially in bright light, to which they are extremely sensitive.
The severity of achromatopsia varies. Although there is no cure or treatment for
this disorder, people with achromatopsia can manage its symptoms. For example,
they can wear sunglasses or tinted contact lenses to cope with bright light.
They can use magnifiers and other devices for
low vision to help them read, and telescopes to
help them see distant objects.
Suggested resource:
www.achromat.org
Acute Zonal Occult Outer Retinopathy (AZOOR)
Acute zonal occult outer retinopathy (AZOOR) is a retinal disease characterized by sudden onset of flashing lights and visual field changes in an individual with a normal retinal exam. It affects women 3 times more frequently than men; most people affected are Caucasian, middle-aged, and myopic. A viral illness has preceded many of the reported cases. Initially only one eye is involved but the other eye may be affected months to years later.
Age-related macular degeneration (ARMD)
See
macular degeneration.
Suggested resources:
Age-Related Macular Degeneration
http://www.amdalliance.org
www.amd.org
Albinism
A hereditary condition characterized by a variable lack of
pigment in the eyes, skin, or hair. People with albinism may have pale pink skin
and blond to white hair, but there are different types of albinism, and the
amount of pigment varies. The irises of their eyes may be white or pinkish. They
are sensitive to bright light and glare and commonly have other vision problems.
While some people with albinism can see well enough to drive, many have impaired
vision or may even be legally blind. Albinism is often accompanied by
nystagmus or
strabismus. People with albinism are sensitive
to bright light and glare and may wear tinted eyeglasses. Bifocals, magnifiers,
and other optical devices can help people with albinism.
Suggested resources:
Albinism
www.albinism.org
Amblyopia
A condition in which a person's vision does not develop properly
in early childhood because the eye and the brain are not working together
correctly. Amblyopia, which usually affects only one eye, is also known as "lazy
eye." A person with amblyopia experiences blurred vision in the affected eye.
However, children often do not complain of blurred vision in the amblyopic eye
because this seems normal to them. Early treatment is advisable, because if left
untreated, this condition may lead to permanent vision problems. Treatment
options include vision therapy exercises or prescription eyeglasses. People with
amblyopia may need to wear an eye patch over their stronger eye in order to
force the affected eye to function as it should.
Suggested resources:
Amblyopia
www.preventblindness.org/children/amblyopiaFAQ.html
Aniridia
Partial or complete absence of the iris of the eye. This rare
condition, usually present at birth, results in impaired vision and sensitivity
to light. People with aniridia are also at high risk for certain other eye
conditions, such as
glaucoma,
nystagmus, and
cataracts. People with aniridia may benefit
from wearing tinted contact lenses or sunglasses, using magnifiers, and avoiding
intense or glaring light.
Suggested resources:
Aniridia
Anophthalmia
Rare condition in which one or both eyes do not form during
pregnancy. When both eyes are affected, blindness results. There is no cure for
anophthalmia. Prosthetic eyes can promote proper growth of the eye sockets and
development of facial bones and also serve cosmetic purposes.
Suggested resource:
www.nei.nih.gov/health/anoph/anophthalmia
Aphakia
Absence of the lens of the eye. Aphakia is usually associated
with the surgical removal of a
cataract but may also result from a wound or
other cause. Without the lens, the eye cannot adjust its focus for seeing at
different distances. Contact lenses or eyeglasses are used to correct the vision
of someone with aphakia. In cataract surgery, an artificial lens is inserted to
replace the lens removed. A person with aphakia will benefit from good, but not
excessive, lighting and high-contrast reading materials.
Suggested resource:
http://www.tsbvi.edu/curriculum-a-publications/970-aphakia
Astigmatism
Common vision condition, usually present from birth, caused by an
irregularly curved cornea or lens. People with astigmatism may experience
blurred vision, eyestrain, or headaches. Two-thirds of Americans who have
myopia also have astigmatism. Astigmatism can
be corrected with eyeglasses or contact lenses. Corrective surgery is another
option.
Suggested resource:
www.nei.nih.gov/health/errors/astigmatism.asp
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Best's Disease
Rare, inherited condition that affects the macula, the area in
the middle of the retina, and can cause blurred or distorted vision or a loss of
central vision. Best's Disease, also known as Vitelliform Macular Dystrophy, may
affect both eyes. The disease's effects on sight vary and may not become severe
for many years, if ever. Most people are not significantly affected until after
age 40. There is no treatment for Best's Disease, but a person whose vision is
impaired by this disease may benefit from devices for
low vision.
Suggested resource:
http://ghr.nlm.nih.gov/condition/vitelliform-macular-dystrophy
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Cataract
A condition in which the lens of the eye, which is normally
clear, becomes cloudy or opaque. Cataracts generally form slowly and without
pain. They can affect one or both eyes. Over time, a cataract may interfere with
vision, causing images to appear blurred or fuzzy and colors to seem faded. Most
cataracts are related to aging. In fact, cataracts affect more than 50 percent
of all adults by age 80 and are the primary cause of vision loss in people 55
and older. People with early cataract may benefit from new eyeglasses, bright
lighting, anti-glare sunglasses, or magnifying lenses. If, despite such devices,
cataract interferes with daily activities, surgery is the only effective
treatment. Cataract surgery, which is common, involves removal of the cloudy
lens and replacement with an artificial lens.
Suggested
resources:
Cataracts
https://nei.nih.gov/health/cataract/
Charles Bonnet syndrome
Visual disturbances usually occurring in people who have
experienced visual impairment or sight loss later in life, as through
macular degeneration. People with Charles
Bonnet syndrome may see a wide range of images, from simple patterns to people,
animals, and buildings. The visual disturbances associated with this syndrome
are not signs of mental illness, and people realize that the images they are
seeing are not real. There is no cure for Charles Bonnet syndrome. However, the
symptoms often stop on their own. People who have Charles Bonnet syndrome should
consult with an eye care specialist because treatment for vision disorders may
help.
Suggested resources:
Charles Bonnet Syndrome
http://syndrome.org/charles-bonnet-syndrome/
Chorioretinal Atrophy
Chorioretinal atrophy is, as the name implies a degeneration, or atrophy of the retina. It affects males more than females. It is an autosomal dominant disorder caused by mutations in the CRB1 gene.
Choroidal Neovascularization
Choroidal neovascularization refers to new and abnormal blood vessels that grow, multiply, and develop into a cluster beneath the macula. The macula is the part of the retina that provides the clearest central vision.
Choroideremia
Rare disorder that causes progressive loss of the choroid, an
important layer under the retina that is responsible for some of its blood
supply. Choroideremia is an inherited disorder that generally affects males
only. It commonly begins as night blindness in childhood and gradually advances
to increasing vision loss. Most people with this disorder are able to retain
good vision until age 40 or 50. There is no treatment for choroideremia, but
people who have the disorder may find it helpful to use optical, electronic, or
computer-based devices for
low vision.
Suggested resource:
http://curechm.org/what-is-choroideremia/
Coloboma
A cleft or gap in some part of the eye, such as the iris, lens,
or retina, that is caused by a defect in the development of the eyeball. How
much coloboma affects a person's vision depends on the size and location of the
cleft and on whether it occurs in one or both eyes. For example, someone with
only a tiny defect in the iris may have normal vision. However, a person with
large defects in the retina and optic nerve may have limited vision. Children
whose vision is impaired by coloboma may benefit from using reading materials
that have large black print and well-spaced letters and words. They may also
find it helpful to read one line at a time with the aid of a cutout reading
window.
Suggested resource:
http://www.tsbvi.edu/curriculum-a-publications/977-coloboma
Color blindness
A vision problem in which a person has difficulty distinguishing
certain colors—most commonly red and green, but sometimes blue and green or blue
and yellow. Color blindness is not really a form of blindness, but rather a
deficiency in color perception. It usually affects both eyes and is much more
common in males than in females. There is no treatment or cure for this problem,
but a color-blind person can learn to adapt in various ways. For example, a
color-blind driver can remember that the light positioned at the top of a
traffic light is the red one. It is beneficial to diagnose color blindness in
children at an early age so that steps can be taken to avoid learning problems
related to color perception.
Suggested resource:
http://www.tsbvi.edu/instructional-resources/69-information-about-color-and-color-blindness
Cone-rod dystrophy
Inherited disease that, over time, causes deterioration of the
specialized light-sensitive cells of the retina. People with cone-rod dystrophy
typically experience decreased sharpness of vision followed by a loss of
peripheral vision and color perception. The most common form of cone-rod
dystrophy is
retinitis pigmentosa. There is no treatment or
cure for this disease, which is also referred to as cone-rod degeneration,
progressive cone-rod dystrophy, and retinal cone dystrophy.
Suggested resources:
www.blindness.org/glossary/cone-rod-dystrophy
Congenital eye defects
Any of various conditions present at birth that affect the eyes or vision. Some congenital eye conditions, such as retinitis pigmentosa, are passed on through genes. Others, such as vision loss due to German measles, result from a disease or deficiency during pregnancy. Sometimes, as in the case of coloboma, the cause of a congenital eye defect is not known. Congenital eye defects can impair vision or even cause blindness. Some conditions are immediately apparent in an infant, while others may not become known until later in life.
Conjunctivitis
Conjunctivitis is inflammation of the conjunctiva, which is the
thin translucent tissue that lines the inner surface of the eyelid and the outer
surface of the sclera, which is the white part of the eye.
Conjunctivitis is usually associated with redness of the white part of the eyes,
light sensitivity (photophobia), excessive tearing, ocular discomfort (gritty
sensation, itching, burning), and/or discharge.
There are many different causes of conjunctivitis. Some types of conjunctivitis
are infectious, while others are not. These can generally be differentiated from
one another based on history and an examination by an eye doctor.
Suggested Resource:
Conjunctivitis
Corneal disease
Disease or disorder that affects the cornea, the clear, curved
surface that covers the front of the eye. The effects of corneal disease vary.
Some corneal conditions cause few, if any, vision problems. For example,
infections of the cornea can often be treated with antibiotics. However, if the
cornea becomes cloudy, light cannot penetrate the eye to reach the retina, and
severe visual impairment, or even blindness, may result. Corneal dystrophies are
usually inherited conditions in which one or more parts of the cornea lose their
clarity due to a buildup of cloudy material.
Keratoconus is the most common corneal
dystrophy in the United States. When corneal disease causes the cornea to become
permanently clouded or scarred, doctors may be able to restore vision with a
corneal transplant—surgical replacement of the old cornea with a new one.
Suggested resource:
http://www.nei.nih.gov/health/cornealdisease/
Cortical visual impairment
Visual impairment caused by damage to those parts of the brain
related to vision. Although the eye is normal, the brain cannot properly process
the information it receives. The degree of vision loss may be mild or severe and
can vary greatly, even from day to day. Also known as cerebral visual
impairment, cortical visual impairment (CVI) may be temporary or permanent.
People with cortical visual impairment have difficulty using what their eye
sees. For example, they may have trouble recognizing faces, interpreting
drawings, perceiving depth, or distinguishing between background and foreground.
Children with cortical visual impairment are often able to see better when told
in advance what to look for. Cortical visual impairment is also known as
neurological visual impairment (NVI).
Suggested resources:
Cortical Visual Impairment, Traumatic Brain Injury, and
Neurological Vision Loss — www.afb.org/cvi
tech.aph.org/cvi/
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De Morsier's Syndrome
Rare disorder, present at birth, in which the optic nerve is underdeveloped, the pituitary gland does not function properly, and often a portion of brain tissue is not formed. De Morsier's Syndrome, also known as septo-optic dysplasia, may cause blindness in one or both eyes and is also often accompanied by nystagmus and various other symptoms. Some children with De Morsier's Syndrome have normal intelligence, while others may be developmentally delayed, learning-disabled, or mentally retarded. Some symptoms of this disorder can be treated, but the visual impairment usually cannot be corrected. Visual devices, such as a magnifier or a computer designed for visually impaired users, may benefit some people with De Morsier's Syndrome.
Diabetic retinopathy
Eye condition that results from the damaging effect of diabetes
on the circulatory system of the retina. The longer someone has had diabetes,
the greater the person's likelihood of developing diabetic retinopathy. Changes
in the tiny blood vessels of the retina can lead to vision loss. People with
diabetes should have routine eye examinations so that diabetes-related problems
can be diagnosed and treated as soon as possible. Maintaining strict control of
blood sugar levels helps to prevent diabetic retinopathy. Surgical and laser
treatments can help many people affected with this condition.
Suggested resources:
Diabetes and Diabetic Retinopathy
www.nei.nih.gov/health/diabetic/retinopathy.asp
Dry eye syndrome
Persistent dryness of the eyes resulting from too little
production of tears or too rapid evaporation of tears. People with dry eye
syndrome may experience such symptoms as itching, burning, or stinging eyes.
Some people feel as though something is caught in their eye, causing an
irritation. Dry eye syndrome has many causes. For example, it may be linked to
wearing contact lenses for long periods of time or to living in a dry or dusty
climate. It may be a side effect of medication or a symptom of certain diseases.
An eye doctor may recommend the application of special eye drops—"artificial
tears"—to moisten the eyes or the use of a humidifier to increase humidity in
the air. Not rubbing the eyes and avoiding such irritants as tobacco smoke can
also help persons with dry eye syndrome.
Suggested resource:
www.dryeye.org/patients.htm
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Floaters and spots
Specks or strands that seem to float across the field of vision.
Floaters and spots are actually shadows on the retina cast by tiny bits of gel
or cells inside the clear fluid that fills the eye. Floaters and spots usually
are normal and harmless. However, in some cases they may warn of serious
conditions such as
retinal detachment,
diabetic retinopathy, or infection. Someone who
experiences a sudden decline in vision accompanied by flashes and floaters or a
sudden increase in the number of floaters should consult an ophthalmologist
urgently.
Suggested resources:
Floaters
www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/spots-and-floaters
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Glaucoma
Disease in which the pressure of the fluid inside the eye is too
high, resulting in a loss of peripheral vision. If the condition is not
diagnosed and treated, the increased pressure can damage the optic nerve and
eventually lead to blindness. Vision lost as a result of such damage cannot be
restored. A person who has glaucoma may not realize it at first, because the
disease often progresses with no symptoms or warning signs. Early detection
through regular eye examination and prompt treatment is essential to prevent
vision loss. Daily medication (usually eye drops), surgery, or a combination of
both enables most people to control their intraocular pressure and retain their
vision.
Suggested resources:
Visual Impairment and Glaucoma
www.glaucoma.org
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H
Hemianopia
Blindness affecting half of the field of vision. Hemianopia, also
known as hemianopsia, may be caused by various medical conditions, but usually
results from a stroke or brain injury. It may affect either the right or left
side of the visual field and is usually permanent. Hemianopia can produce
various effects, from minor to severe. For example, a person may be able to see
only to one side when looking ahead, or objects that the person sees may differ
in clarity or brightness. Such visual impairment can make it difficult to
perform daily tasks, from reading to crossing streets. There is no specific
treatment for hemianopia, but
low vision rehabilitation specialists can help
people learn to make the most of the sight that they have. In addition, some
people with hemianopia benefit from the use of magnifiers or special prism
lenses.
Suggested resources:
www.lowvision.org/new_page_1hemi.htm
http://www.tsbvi.edu/instructional-resources/986-hemianopsia
Hyperopia
This common vision problem, also known as farsightedness, occurs
when light rays entering the eye focus behind the retina, not directly on it.
People with hyperopia are usually able to see distant objects well, but close
objects appear blurry. Hyperopia may cause eyestrain or headaches, especially
with reading. Eyeglasses or contact lenses can correct hyperopia. For people who
do not want to wear glasses or contact lenses, laser vision correction is
sometimes possible.
Suggested resource:
http://www.aoa.org/x4696.xml
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Keratoconus
Rare condition, often inherited, in which the cornea becomes
progressively thinner and gradually bulges outward, causing blurred or distorted
vision. Keratoconus usually affects both eyes. At first, people with this
condition can correct their sight with eyeglasses. However, as symptoms worsen
over time, specially designed contact lenses are needed to improve vision. Most
people with keratoconus will not experience severe visual impairment. However,
as many as one in five will eventually require a corneal transplant (surgical
replacement of the old cornea with a new one).
Suggested resource:
www.nkcf.org
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Late-Onset Retinal Degeneration (L-ORD)
A genetic retinal disorder. Onset typically occurs in the fifth to sixth decade of a person’s life. Symptoms include night blindness, progressing to severe central and peripheral degeneration with choroidal neovascularization and chorioretinal atrophy. Because it is late onset, it is often mistaken for regular macular degeneration. Note, however, that this disorder, in its severest state, affects both central and peripheral vision and thus leads to total blindness, unlike some of the more common macular disorders.
Laurence-Moon-Bardet-Biedl Syndrome
Rare, inherited disorder affecting many parts of the body. People
with this condition have
retinitis pigmentosa accompanied by mental
retardation, paralysis of the legs, and various other symptoms.
Suggested resource:
http://rarediseases.about.com/od/rarediseasesl/a/lmbbs.htm
Leber's congenital amaurosis
Inherited condition, probably caused by degeneration of the
retina, in which an infant is born blind or develops severe vision loss soon
after birth. Children with Leber's congenital amaurosis typically also have
nystagmus, and some also have mental
retardation and hearing disorders. At present, there is no treatment for this
condition.
Suggested resources:
Foundation for Retinal Research
www.tsbvi.edu/seehear/spring01/lebers.htm
Legal blindness
A level of visual impairment that has been defined by law to determine eligibility for benefits. It refers to central visual acuity of 20/200 or less in the better eye with the best possible correction, or a visual field of 20 degrees or less.
Low vision
Vision loss that may be severe enough to impede a person's
ability to carry on everyday activities, but still allows some functionally
useful sight. Low vision may be caused by
macular degeneration,
cataracts,
glaucoma, or other eye conditions or diseases.
Low vision may range from moderate impairment to near-total blindness. It cannot
be fully corrected by eyeglasses, contact lenses, or surgery. However, a person
with low vision may benefit from any of a variety of available optical devices,
such as electronic magnifying glasses or eyeglass-mounted telescopes. In
addition, special software developed for computer users with low vision can
display type in large size or read text aloud.
Suggested resource:
www.lowvision.org
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Macular degeneration
Disease that causes dysfunction of the macula, the area in the
middle of the retina that makes possible the sharp central vision needed for
such everyday activities as reading, driving, and recognizing faces and colors.
The condition is commonly known as age-related macular degeneration (AMD) and is
the leading cause of visual impairment among older people. However, there are
also other types of macular degeneration, such as
Stargardt's Disease and
Best's Disease. Macular degeneration causes
blurred, distorted, or dim vision or a blind spot in the center of the visual
field. Peripheral vision is generally not affected. This condition is painless
and may progress so gradually that the affected person at first notices little
change. There is no cure for macular degeneration, but drug therapy, laser
surgery, or other medical treatment may in some cases be able to slow the
disease's progression or prevent further vision loss. People with macular
degeneration can also benefit from the use of various devices for
low vision, such as magnifiers, high-intensity
lamps, and pocket-sized telescopes.
Suggested resources:
Age-related Macular Degeneration (AMD)
www.amd.org
www.brightfocus.org/macular
Macular hole
A macular hole is a full thickness hole in the central part of
the retina called the macula. It may be caused by injury or inflammatory
swelling of the retina, but most commonly occurs as an age-related event without
any predisposing conditions. Macular holes are thought to be caused by
tractional forces associated with the vitreous gel separating from the retina in
the macula and around the central macula called the fovea. Surgery is the
treatment of choice for full-thickness macular holes.
Suggested resources:
Macular Hole
Marfan Syndrome
Disorder of the connective tissue, affecting the heart and blood
vessels, skeletal system, eyes, and other parts of the body. The condition is
present at birth. Symptoms vary from person to person, ranging from mild to
severe. People with Marfan syndrome are often nearsighted (see
myopia), and about half have dislocation of one
or both lenses of the eye. There is no cure for Marfan syndrome. Treatment
depends on which body systems are affected. Early eye examinations can detect
vision problems related to the disorder, which can usually be corrected with
eyeglasses, contact lenses or eye surgery.
Suggested resource:
www.marfan.org
Microphthalmia
Rare disorder, usually inherited, in which one or both eyes are
abnormally small. The degree of visual impairment varies, from reduced vision to
blindness. Extreme microphthalmia resembles some forms of
anophthalmia. There is no treatment or cure for
microphthalmia. In certain cases, artificial eyes can be used to promote proper
growth of the eye sockets and to help with cosmetic appearance.
Suggested resource:
http://www.nei.nih.gov/health/anoph/
Myopia
This condition, commonly known as nearsightedness, occurs when
light rays entering the eye focus in front of the retina, not directly on it.
People with myopia are usually able to see close objects well, but objects in
the distance—such as highway signs or writing on a chalkboard—appear blurred.
People with this condition may squint to see distant objects and experience
eyestrain or, sometimes, headaches. Eyeglasses or contact lenses can correct
myopia. Surgery is another alternative.
Suggested resource:
http://www.aoa.org/myopia.xml
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Neurological visual impairment (NVI)
See
cortical visual impairment.
Suggested resource:
www.sfsu.edu/~cadbs/Eng022.html
Neuromyelitis optica (NMO)
Neuromyelitis optica (NMO), also known as Devic's disease, is an autoimmune disorder in which immune system cells and antibodies mistakenly attack and destroy myelin cells in the optic nerves (neuritis) and the spinal cord (myelitis). NMO leads to loss of myelin, which is a fatty substance that surrounds nerve fibers and helps nerve signals move from cell to cell. The syndrome can cause blindness in one or both eyes and can be followed by varying degrees of paralysis in the arms and legs. Most individuals with the syndrome experience clusters of attacks months or years apart, followed by partial recovery during periods of remission. The onset of NMO varies from childhood to adulthood, with two peaks, one in childhood and the other in adults in their 40s. The syndrome is sometimes confused with multiple sclerosis (MS) because both can cause attacks of optic neuritis and myelitis.
Non-24-Hour Sleep-Wake Disorder (Non-24)
Non-24-Hour Sleep-Wake Disorder (Non-24) is a serious, chronic,
and rare circadian rhythm disorder that affects a majority of totally blind
individuals who lack light perception and cannot reset their master body clocks
to the 24-hour day. Non-24 is most commonly found in blind individuals who
cannot perceive light, the primary environmental cue for synchronizing their
circadian rhythm to the 24-hour day. In the United States, this disorder affects
approximately 80,000 totally blind individuals who lack the light sensitivity
necessary to reset their internal "body clocks." In general, individuals with
Non-24 suffer from a variety of clinical symptoms as they cycle into and out of
phase, resulting in disrupted nighttime sleep patterns and/or excessive daytime
sleepiness.
Suggested resources:
FDA Approval for Drug That Regulates Sleep Patterns
Discovering That I Had Non-24
Nystagmus
Condition that involves involuntary, rapid, repetitive movements
of one or both eyes from side to side, up and down, or in a circular motion.
Nystagmus may be present at birth or, less commonly, may result from disease or
injury. In some cases, the condition can reduce or interfere with vision. For
example, children with nystagmus may frequently lose their place when reading.
Placing a cutout reading window over words or using a card to "underline" text
can be helpful.
Suggested resource:
www.nystagmus.org
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Optic nerve atrophy
Degeneration of the optic nerve, which carries vision information from the eye to the brain. People who have optic nerve atrophy may have dimmed or blurred vision as well as a reduced field of vision. They may also have difficulty seeing contrast and fine detail. Vision loss through optic nerve atrophy is permanent. However, if the underlying cause can be identified and successfully treated, further vision loss may be prevented. Bright lighting, high contrast, and bold colors can help children with optic nerve atrophy see more clearly.
Optic nerve hypoplasia
Condition, present at birth, in which the optic nerve is
underdeveloped, so that adequate visual information is not carried from the eye
to the brain. The effects of optic nerve hypoplasia have a broad range, from
little or no visual impairment to near-total blindness. The condition may affect
one or both eyes. There is no treatment or cure for optic nerve hypoplasia.
However, depending on the degree of visual impairment, a person with this
condition may benefit from the use of devices for
low vision.
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Presbyopia
The eye's gradually decreasing ability to focus on nearby
objects. Presbyopia is a normal part of aging and affects virtually everyone,
usually becoming noticeable after age 40. People with presbyopia typically hold
reading materials at arm's length in order to bring the words into focus. They
may experience headaches or eyestrain while reading, viewing a computer screen,
or doing close work. Presbyopia can be corrected with reading glasses, bifocal
or variable focus lenses, or contact lenses. Using bright, direct light when
reading is also helpful.
Suggested resources:
http://www.aoa.org/presbyopia.xml
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Retinal detachment
Separation of the retina from the underlying supportive tissues.
Retinal detachment may result from injury, disease, or other causes. A person
with retinal detachment usually does not experience pain, but may see floaters
(see
floaters and spots) or bright flashes of light,
may have blurred vision, or may see a shadow or curtain over part of the field
of vision. Retinal detachment requires prompt medical attention to prevent
permanent vision loss. There are several methods of treatment for retinal
detachment, including laser surgery.
Suggested resource:
www.nei.nih.gov/health/retinaldetach/index.asp
Retinitis pigmentosa
Degeneration of the retina, resulting in decreased night vision,
a gradual loss of peripheral vision, and in some cases, loss of central vision.
The degeneration progresses over time and can lead to blindness. Retinitis
pigmentosa is a rare, inherited disease for which there is as yet no treatment
or cure. Some ophthalmologists believe that treatment with high doses of Vitamin
A can slow the progression of retinitis pigmentosa, and that taking Vitamin E
makes it worse. Early diagnosis enables a person with the disease to plan and
prepare for its progression. In addition, depending on the degree of vision
loss, electronic magnifiers, night-vision scopes, and other such special devices
for impaired vision can provide some benefit for people with the disease.
Suggested resource:
http://www.blindness.org/eye-conditions/retinitis-pigmentosa
Retinoblastoma
Malignant tumor (cancer) of the retina, generally affecting
children under the age of 6. Usually hereditary, retinoblastoma may affect one
or both eyes. Retinoblastoma has a cure rate of over 90 percent if treated
early. Without prompt treatment, the cancer can spread to the eye socket, the
brain, and elsewhere, and can cause death. Depending on the size and location of
the tumor, treatment options include laser surgery, cryotherapy (a freezing
treatment), radiation, and chemotherapy. In some cases, the affected eye may
need to be removed.
Suggested resource:
www.aoa.org/x8066.xml
Retinopathy of prematurity (ROP)
Condition associated with premature birth, in which the growth of
normal blood vessels in the retina stops, and abnormal blood vessels develop. As
a result, the infant has an increased risk of detachment of the retina (see
retinal detachment). Retinopathy of prematurity
can lead to reduced vision or blindness. Laser therapy can help this condition
if diagnosis and treatment occur early. Children who experience minor effects
may benefit from the use of devices for
low vision as they get older. Retinopathy of
prematurity was formerly called retrolental fibroplasia.
Suggested resources:
www.ropard.org
http://www.nei.nih.gov/health/rop/index.asp
Retrolental fibroplasia
See retinopathy of prematurity.
Rod-cone dystrophy
See
Cone-rod dystrophy.
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Scotoma
Gap or blind spot in the field of vision that may result from
damage to the retina. How much a scotoma impairs sight depends mainly on whether
it affects central or peripheral vision. Common causes of scotoma include
macular degeneration,
glaucoma, and inflammation of the optic nerve.
People who experience significant vision loss because of scotomas may benefit
from the use of magnifiers, bright lighting, and large-print reading materials.
Suggested resource:
http://www.tsbvi.edu/curriculum-a-publications/1093-scotoma
Septo-Optic Dysplasia (SOD)
See
De Morsier's Syndrome.
Suggested resources:
www.focusfamilies.org/focus/usdefault.asp
www.ninds.nih.gov/health_and_medical/disorders/septo-optic.htm
Stargardt's Disease
Inherited disease that causes gradual degeneration of the macula,
the area in the middle of the retina that makes possible the central vision
needed for reading, driving, recognizing colors, and other activities of daily
life. Effects of Stargardt's Disease, which start at an early age, vary from
minor to total loss of detail vision. Over a period of years, people with the
disease typically lose sharpness of vision, experience decreased color vision,
and may have blind spots. However, peripheral and night vision usually remain
unaffected, and complete loss of sight is rare. There is no cure or treatment
for Stargardt's Disease, but such devices as magnifying screens and binocular
lenses can help people cope with vision limitations.
Suggested resource:
www.mdsupport.org/library/stargrdt.html
Strabismus
Condition in which the eyes are not both directed toward the same
point simultaneously. Strabismus occurs when eye muscles are not working
together properly. It is most commonly an inherited condition, but may also be
caused by disease or injury. If diagnosed early, strabismus can usually be
corrected. The condition may be treated with corrective eyeglasses, eye-muscle
exercises, surgery, or a combination of these approaches. Young children with
this condition may need to wear an eye patch over their stronger eye to force
their weaker eye to function correctly. Children whose strabismus is not
corrected may develop
amblyopia.
Suggested resource:
http://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/strabismus?sso=y
Sturge-Weber Syndrome
Disorder, present at birth, characterized by a facial birthmark
and any of various neurological, visual, and developmental symptoms. People with
Sturge-Weber syndrome may, for example, experience seizures,
glaucoma, partial paralysis, and learning
disabilities. There is no cure for Sturge-Weber syndrome, but many of the
symptoms can be treated. For instance, medications may be prescribed to control
seizures, and surgery or eye drops may be used to treat glaucoma.
Suggested resource:
http://sturgeweber.kennedykrieger.org/
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Trachoma
Contagious eye infection, caused by bacteria, that affects the
eyelid and cornea. Trachoma can lead to scarring and blindness if not treated.
The infection is spread by contact with discharge from the eyes or nose of
infected persons and also transmitted by certain flies. Trachoma is rare in the
United States, but it affects millions of people around the world, many of them
children. Antibiotics are generally an effective treatment for trachoma,
especially if used early in the infection. In certain cases, eyelid surgery may
be needed.
Suggested resource:
www.trachoma.org
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Usher Syndrome