Glaucoma
View
This Disease
Back To Top
What is glaucoma?
In some types of glaucoma, pressure in the eye is increased. The term
used by health professionals to describe the pressure in the eye is intraocular
pressure, or IOP.
What types of glaucoma are there?
Primary open-angle glaucoma (POAG) is the most common form of the
disease. Restriction of the drainage angle in the eye keeps excess fluid
from escaping. Most people are not even aware of a problem until the vision
is damaged. In angle-closure glaucoma, the eye's drainage system becomes
completely blocked. If the pressure builds up suddenly, it can cause severe
eye pain, blurred vision, and headache.
What causes increased IOP?
The eye produces a fluid (aqueous humor) that
helps to bathe and nourish the inside of the eye and helps hold its shape.
The fluid flows out of
the eye through a drainage system. A clog in this drainage system traps
fluid inside the eye, increasing the IOP. The cause of changes in the
eye that result in high pressure is not known.
How does glaucoma affect vision?
Researchers believe that elevated pressure
on the optic nerve damages the nerve. This damage slowly causes vision
loss and reduction of the
visual field. The visual field is the entire area seen at a given time
without moving the eyes. Usually in open-angle glaucoma, vision loss
starts at the edges of the visual field, and moves toward the center.
If open-angle glaucoma is not treated, a person's visual field gets smaller
and smaller, as though looking through a tunnel. The disease process
may lead to blindness.
Who is at risk?
Unfortunately, most people who have increased eye pressure
have no symptoms. Predicting risk exactly is impossible. In general, patients
are at greater
risk for open-angle glaucoma if they have:
High intraocular pressure (IOP)
A family history of glaucoma
African descent
Severe nearsightedness (myopia)
Diabetes
Older than 45 years
Used steroids or cortisone for a long time
Had a previous eye injury
How is glaucoma diagnosed?
Because glaucoma usually has no symptoms and
may cause blindness, your greatest risk is not knowing if you have it!
A simple test at your eye
doctor's office provides a diagnosis. Don't wait. Studies suggest that
early diagnosis and treatment can help slow or stop the likelihood of
glaucoma progression.
How is glaucoma treated?
You are the most important part of your glaucoma
treatment. By becoming informed, you play an important role in successful
treatment. Remember
that glaucoma is the leading cause of preventable blindness in the United
States. Eye pressure control is the primary goal of glaucoma treatment.
Studies suggest that lowering IOP can help slow further vision loss. The
damage
already caused by glaucoma can't be reversed. Prescription eye drops or
pills help reduce IOP. It is very important to take the medications regularly,
even if you experience no pain or
symptoms. Your doctor will also want to monitor your progress during
regularly scheduled appointments. If medication is ineffective or causes
side effects, laser or traditional surgery may be recommended. Laser surgery
or trabeculoplasty is a relatively
painless outpatient procedure that effectively lowers IOP in most cases.
Some patients may need eye drops or a repeat laser procedure to control
IOP. If both medical and laser treatment are ineffective, an alternate
passage for drainage can be created surgically (trabeculectomy). More than
three-quarters
of patients treated surgically experience adequately controlled IOP afterwards.
Sometimes pressure-lowering medications are also required.
|
Macular
Degeneration
View
This Disease
Back To Top
What is macular degeneration?
People with age-related macular degeneration lose their central vision
because of damage to the macula, an area at the back of the eye that
allows us to see fine details. Although central vision blurs or darkens,
side vision is not affected. Eventually, activities like reading and
driving become impossible. Macular degeneration is the leading cause
of vision loss in seniors but usually does not result in total blindness.
Most people with macular degeneration retain enough useful vision to
live independently.
What are dry
stage and wet stage macular degeneration?
In dry stage macular degeneration, the most common form of the disease,
macular tissues thin and slowly lose function. Wet macular degeneration
is caused by abnormal blood vessels that grow behind the macula. These
blood vessels frequently leak, causing scar tissue to form. The wet stage
of the disease is less common but usually more damaging than the dry stage.
Left untreated, wet macular degeneration may rapidly
worsen. In general, approximately 14 to 20% of cases of dry stage macular
degeneration progress to wet stage disease.
What are the
symptoms of macular degeneration?
Loss of the ability to see objects clearly
Distorted vision - straight lines appear to be wavy
Loss of clear and correct color vision
Difficulty reading
Central vision blocked by a dark area
Having one or more of these symptoms does not necessarily mean you have
macular degeneration. However, if you have any of these symptoms, you should
see your eye doctor immediately.
Who is at risk for developing macular degeneration?
The disease is more common in people who have a family history of macular
degeneration, light complexion, history of heart disease or lung infection,
and smokers.
How is macular degeneration treated?
Currently there is no treatment for dry
stage macular degeneration. You should still see an eye doctor regularly
so that the condition can be monitored
along with your general health. Your doctor may also prescribe vitamins
C and E plus zinc. Some cases of wet macular degeneration can be treated
with lasers. The laser treatment seals off leaking blood vessels, slowing
or preventing
additional damage to the eye. No treatment can restore sight that has already
been lost due to dry or wet stage macular degeneration.
|
Cataracts
View
This Disease
Back To Top
What are cataracts?
Cataracts are cloudy areas on the lens of the eye. At first they may
go unnoticed. As the cloudiness expands, cataracts left untreated can
significantly affect vision. Over half of all people age 65 or older
has cataracts.
What are the signs and symptoms of cataracts?
Blurred vision
Sensitivity to bright light
Difficulty driving at night
Nearsightedness that continues to get worse
Change in color vision (yellow, orange, and red appear brighter and blue
appears dull)
What causes cataracts?
What causes cataracts is not known, but many factors may contribute
to their formation.
Exposure to toxic substances or radiation, especially
x-rays.
Prolonged exposure to sunlight.
Long-term use of steroid medication.
Rubella: A baby whose mother has German measles (rubella) during pregnancy
may develop cataracts.
Galactosemia: 10 - 30% of newborns with this disease may develop cataracts
within days or weeks of birth. Babies with galactosemia are treated with
a diet that excludes the milk sugar called galactose.
Eye injury
Disease: Inflammatory eye diseases (iritis) or diabetes.
How are cataracts diagnosed?
Cataracts usually develop slowly and painlessly.
An eye examination by a physician can detect cataracts, even before they
interfere with
vision. Having regular eye examinations is an important way to protect
your vision, especially as you get older.
Can cataracts be prevented?
You can reduce the risk of developing cataracts
by wearing glasses that protect your eyes from injury during work or high-risk
sports. You can
also protect your eyes from the harmful effects of sunlight by wearing
sunglasses that block ultraviolet (UV) rays.
How are cataracts treated?
Surgery may be necessary to treat cataracts.
An ophthalmologic surgeon may remove the lens if it begins to interfere
with the sight needed for
daily activities. The surgeon makes a small cut in your eye, removes
the cloudy lens, and implants a plastic intraocular lens (an IOL). At
the end of the procedure, a patch may be placed over the eye. When both
eyes are affected by cataracts, surgery is usually performed on the worst
eye first. After that eye has healed, the cataract in the other eye is
removed.
|
Myopia
View
This Disease
Back To Top
What is myopia?
Myopia or nearsightedness is very common and is usually inherited. Myopia
is a refractive disorder not a disease. The shape of the eye distorts
light so that distant objects appear blurred. Myopia often progresses
during the teenage growing years. People with high myopia have a higher
risk of detached retina and glaucoma.
What are the symptoms of myopia?
Blurred vision
Difficulty seeing distant objects
How is myopia treated?
Eyeglasses or contact lenses can correct the refractive
error caused by myopia. Some types of myopia can be corrected surgically.
|
Astigmatism
View
This Disease
Back To Top
What is astigmatism?
Astigmatism
is a refractive or focusing error. People with astigmatism cannot focus light
to a single point inside the eye. As a result, their
vision is distorted. Astigmatism is generally caused by an irregular
curvature of the cornea, the outer transparent covering of the eye. Astigmatism
is very common and the tendency to develop astigmatism is inherited.
What are the signs and symptoms of astigmatism?
Blurred or distorted
vision
Headache and fatigue
Squinting
Eye discomfort or irritation
How is astigmatism treated?
Slight astigmatism may not require any treatment.
If astigmatism causes eyestrain, headache or vision problems, corrective
or contact lenses can
be prescribed. Surgery can correct some forms of astigmatism. Astigmatism
may change over time, so it's a good idea to schedule regular eye examinations.
|
Hyperopia
View
This Disease
Back To Top
What is hyperopia?
Hyperopia or farsightedness is very common and is usually inherited.
Hyperopia is a refractive disorder not a disease. The shape of the eye
distorts light so that nearby objects appear blurred. More distant objects
may be seen clearly. Hyperopia in children may improve as they grow older.
What are the symptoms of hyperopia?
Blurred vision
Difficulty seeing close objects
Crossed eyes in children
How is hyperopia treated?
Eyeglasses or contact lenses can correct the refractive error caused by
hyperopia. Some types of hyperopia can be corrected surgically.
|
Retinitis
Pigmentosa (Day)
View
This Disease
Back To Top
What is retinitis pigmentosa?
Retinitis pigmentosa is actually
a group of diseases that cause a slow progressive vision loss. Approximately
200,000 Americans have some form
of retinitis pigmentosa. In most cases, retinitis pigmentosa is inherited,
although it may skip generations. People with retinitis pigmentosa
may also develop other treatable eye diseases, such as glaucoma or cataracts.
What are the symptoms of retinitis pigmentosa?
Night blindness
Loss of side vision
What causes retinitis pigmentosa?
People with retinitis pigmentosa gradually
lose the light-sensitive cells at the back of the eye. These cells of the
retina are called rods and cones.
As the cells die, vision decreases.
How is retinitis pigmentosa treated?
At present there is no cure for retinitis pigmentosa. The progress of
the disease can sometimes be slowed to preserve vision. Current research
focuses on the genetic factors. Understanding how retinitis pigmentosa
is passed along could help in finding a way to treat or prevent it.
|
Retinitis
Pigmentosa (Night)
View
This Disease
Back To Top
What is retinitis pigmentosa?
Retinitis pigmentosa is actually a group of diseases that cause a slow
progressive vision loss. Approximately 200,000 Americans have some form
of retinitis pigmentosa. In most cases, retinitis pigmentosa is inherited,
although it may skip generations. People with retinitis pigmentosa may
also develop other treatable eye diseases, such as glaucoma or cataracts.
What are the symptoms of retinitis pigmentosa?
Night blindness
Loss of side vision
What causes retinitis pigmentosa?
People with retinitis pigmentosa gradually lose the light-sensitive
cells at the back of the eye. These cells of the retina are called rods and
cones.
As the cells die, vision decreases.
How is retinitis pigmentosa treated?
At present there is no cure for retinitis pigmentosa. The progress of
the disease can sometimes be slowed to preserve vision. Current research
focuses on the genetic factors. Understanding how retinitis pigmentosa
is passed along could help in finding a way to treat or prevent it.
|
Diabetic
Retinopathy (Proliferative)
View
This Disease
Back To Top
What is diabetic retinopathy?
People with diabetes mellitus cannot use or store sugar properly. High
levels of sugar in the blood can damage blood vessels in the retina,
the nerve tissue at the back of the eye that transmits visual information
to the brain. Diabetes can also damage sight by causing glaucoma, increased
pressure inside the eye, or cataracts.
What are non-proliferative and proliferative diabetic retinopathy?
In non-proliferative diabetic retinopathy blood vessels within the retina
leak blood or fluid. The leaking causes swelling. Blood may also cloud
the clear gel (vitreous) inside the eye. Many patients with diabetes have
a mild form of diabetic retinopathy, which usually does not affect their
vision. If, however, damage to the retina causes swelling (macular edema)
or closes off small blood vessels (macular ischemia), vision suffers. In
proliferative diabetic retinopathy, abnormal new blood vessels grow on
the retina or optic nerve. The new growth is in response to the closure
of other blood vessels that supply the retina. Unfortunately, the new vessels
often create scar tissue that damages the retina. Proliferative diabetic
retinopathy can cause severe vision loss. Bleeding into the vitreous can
impair or block vision too. The blood usually resorbs over months or years.
If it doesn't clear adequately, the blood and vitreous may need to be removed
surgically.
What eye signs and symptoms accompany diabetic retinopathy?
Large fluctuations in refraction
Changes in the cornea, the transparent outer layer of the eye
Cataracts
Optic nerve damage
Who is at risk for diabetic retinopathy?
People with untreated diabetes have a 25 times higher risk of going blind
than other people. The longer a person has had diabetes, the greater the
risk of developing diabetic retinopathy. Therefore, the condition is more
common in patients with juvenile-onset or Type 1 diabetes. Every year 8000
Americans go blind because of diabetic retinopathy.
How is diabetic retinopathy diagnosed?
An eye examination is the only way
to find diabetic retinopathy. A medical eye exam may diagnose diabetic
retinopathy before a patient notices any
vision problems.
How is diabetic retinopathy treated?
The best treatment is to prevent the development of retinopathy as
much as possible. Strictly controlling blood sugar helps to reduce
the risk of vision loss from diabetic retinopathy. High blood pressure
and kidney problems should also be treated. Laser treatment is often
recommended for macular edema, proliferative diabetic retinopathy,
or glaucoma associated with new blood vessel growth. The goal of treatment
is to preserve existing vision. In severe cases of proliferative diabetic
retinopathy, vitrectomy is recommended. During this microsurgical procedure,
the surgeon removes abnormal blood vessels, and the blood-filled gel
(vitreous) inside the eye. The vitreous is replaced with a clear solution.
Can vision loss be prevented?
Yes. The best way to protect vision is to detect and treat diabetic
retinopathy early. That means regular visits to your eye doctor,
especially if you have a family history of diabetes. People with
diabetes can protect their eyesight by strictly controlling their
blood sugar. They should see an eye doctor at least once a year or
if they notice any changes in vision. Women who have diabetes and
become pregnant should see an eye doctor during the first trimester.
Diabetic retinopathy can progress quickly during pregnancy.
|
Diabetic
Retinopathy (Non-Proliferative)
View
This Disease
Back To Top
What is diabetic retinopathy?
People with diabetes mellitus cannot use or store sugar properly. High
levels of sugar in the blood can damage blood vessels in the retina,
the nerve tissue at the back of the eye that transmits visual information
to the brain. Diabetes can also damage sight by causing glaucoma, increased
pressure inside the eye, or cataracts.
What are non-proliferative and proliferative diabetic retinopathy?
In non-proliferative diabetic retinopathy blood vessels within the retina
leak blood or fluid. The leaking causes swelling. Blood may also cloud
the clear gel (vitreous) inside the eye. Many patients with diabetes have
a mild form of diabetic retinopathy, which usually does not affect their
vision. If, however, damage to the retina causes swelling (macular edema)
or closes off small blood vessels (macular ischemia), vision suffers. In
proliferative diabetic retinopathy, abnormal new blood vessels grow on
the retina or optic nerve. The new growth is in response to the closure
of other blood vessels that supply the retina. Unfortunately, the new vessels
often create scar tissue that damages the retina. Proliferative diabetic
retinopathy can cause severe vision loss. Bleeding into the vitreous can
impair or block vision too. The blood usually resorbs over months or years.
If it doesn't clear adequately, the blood and vitreous may need to be removed
surgically.
What eye signs and symptoms accompany diabetic retinopathy?
Large fluctuations in refraction
Changes in the cornea, the transparent outer layer of the eye
Cataracts
Optic nerve damage
Who is at risk for diabetic retinopathy?
People with untreated diabetes have a 25 times higher risk of going blind
than other people. The longer a person has had diabetes, the greater the
risk of developing diabetic retinopathy. Therefore, the condition is more
common in patients with juvenile-onset or Type 1 diabetes. Every year 8000
Americans go blind because of diabetic retinopathy.
How is diabetic retinopathy diagnosed?
An eye examination is the only way to find diabetic retinopathy. A medical
eye exam may diagnose diabetic retinopathy before a patient notices any
vision problems.
How is diabetic retinopathy treated?
The best treatment is to prevent the development of retinopathy as
much as possible. Strictly controlling blood sugar helps to reduce
the risk of vision loss from diabetic retinopathy. High blood pressure
and kidney problems should also be treated. Laser treatment is often
recommended for macular edema, proliferative diabetic retinopathy,
or glaucoma associated with new blood vessel growth. The goal of treatment
is to preserve existing vision. In severe cases of proliferative diabetic
retinopathy, vitrectomy is recommended. During this microsurgical procedure,
the surgeon removes abnormal blood vessels, and the blood-filled gel
(vitreous) inside the eye. The vitreous is replaced with a clear solution.
Can vision loss be prevented?
Yes. The best way to protect vision is to detect and treat diabetic
retinopathy early. That means regular visits to your eye doctor,
especially if you have a family history of diabetes. People with
diabetes can protect their eyesight by strictly controlling their
blood sugar. They should see an eye doctor at least once a year or
if they notice any changes in vision. Women who have diabetes and
become pregnant should see an eye doctor during the first trimester.
Diabetic retinopathy can progress quickly during pregnancy.
Additional Resources
Ophthalmology
Resource Center
International Glaucoma
Association
American Academy
of Ophthalmology
Anatomy
of the Eye
Glaucoma
Foundation
American Society
of Cataract & Refractive Surgery
Macular Degeneration Help
Center
Foundation Fighting
Blindness
Glaucoma Research Foundation
International Council of
Ophthalmology
International Society of
Refractive Surgery
Macular
Degeneration Network
National Alliance
for Eye and Vision Research
Optical Society of America
Prevent Blindness
America
|
