What is uveitis?
The uvea is the middle layer of the wall of
the eye. It has three parts: the iris, the
ciliary body and the choroid. Inflammation
(or swelling) of any part of the uvea is
called "uveitis." Uveitis can be classified
by the area involved. If the primary area
involved is the iris, the condition is
called "iritis"; the ciliary body, "cyclitis",
and the choroid, "choroiditis." Uveal
inflammation may also involve adjacent
tissues. For example, choroiditis may spread
to the retina and thus becomes a "chorioretinitis."
In order to help diagnose what specific type
of uveitis you may have, it is important for
the ophthalmologist to locate the source of
the inflammation. Once the source is
located, the physician can best treat the
condition and predict the long-term visual
outcome.
The symptoms of uveitis depend upon the area
that is inflamed and the duration of
inflammation. Acute iritis may cause a red
eye with pain and sensitivity to light.
Chronic and posterior inflammation may be
painless but may cause symptoms such as
floaters or decreased vision. These symptoms
should alert you to seek expert medical
attention promptly.
How is uveitis
treated? Untreated uveal inflammation can lead to
blindness. Cataract, glaucoma, retinal
scarring, retinal detachment, optic nerve
damage and atrophy or shrinkage of the eye
are some of the potential complications of
persistent uveitis. Many patients with
uveitis have good vision as their disease is
managed by medicines and eye drops.
A careful medical history, including family,
social and sexual history, is important in
the uveitis patient. Evaluation of uveitis
is directed toward the diagnosis and
identification of possible underlying causes
of the disease. Bacteria, fungi, viruses,
protozoa or other agents along with
abnormalities of the immune system can cause
uveitis. Testing may involve blood tests,
X-rays, special ocular studies or evaluation
by other skilled medical consultants beyond
ophthalmology.
A full medical evaluation may reveal an
inflammatory disease that has involved other
organs besides the eye. Examples of this
include sarcoidosis, rheumatoid arthritis
and related conditions. For these types of
conditions, treatment for the underlying
cause of the uveitis helps all parts of the
body, including the eye.
In most cases, no obvious underlying cause
is found for the uveitis. Treatment then is
directed to the eye inflammation alone.
Treatment may include drops or injections of
cortisone medication around the eye.
Sometimes it may be necessary to use oral
drugs that suppress inflammation, such as
prednisone or cytotoxic (chemotherapeutic)
agents. Treatment can be prolonged for
uveitis. Therefore, close followup with an
ophthalmologist is important to keep the eye
functional and to detect occasional side
effects from the treatments.
How common is diabetic
retinopathy? Because there are so many diabetics in
India, diabetic retinopathy is becoming the
leading cause of new cases of blindness
among people aged 20 to 74 years. Persons
with diabetes need to regularly check their
blood sugar levels to be sure they are
maintaining blood sugar levels that are as
near normal as possible. They should also
regularly see their primary healthcare
provider as well as keep regular checkups
with their ophthalmologist even if they are
not having vision problems.
What is diabetic
retinopathy?
Diabetic retinopathy is a complication of
diabetes that affects the eyes by causing
deterioration of the blood vessels in the
retina. These weakened vessels may leak
fluid or blood, develop brushlike branches,
or become enlarged.
Is it safe for a woman
with diabetic retinopathy to become
pregnant?
Most diabetic women can have a baby without
an increase in retinopathy. In some
patients, however, the retinopathy might
worsen enough to require laser
photocoagulation. In a few cases, vision
might remain decreased. It is recommended
that all patients be frequently monitored
during pregnancy. Generally, this means a
baseline examination and visits at least
every three months.
Can retinopathy be
delayed by keeping blood sugar under
control?
A recent national study showed that strict
control of blood sugar can markedly delay
the onset of diabetic retinopathy and can
slow the progression of early cases. All
diabetics should strive for good control of
their blood sugar because some patients,
even those with more advanced diabetic
retinopathy, might delay the progression of
the disease if their blood sugar is
maintained at a reasonable level. Others,
however, will see a progression of the
disease even if their blood sugar is normal
or near normal.
Does high blood
pressure affect the eyes?
Some studies have shown the patients with
high blood pressure are more likely to have
retinopathy. However, since high blood
pressure alone can damage the eyes, heart,
kidneys and brain, patients should keep
their blood pressure under control and have
it monitored regularly.
Why would a person
with no vision problems require laser
treatment?
Patients with proliferative retinopathy
might have normal vision but are still at
high risk for imminent loss of vision due to
hemorrhage or retinal detachment. Laser
photocoagulation in these patients has been
proven to be effective by the Diabetic
Retinopathy Study.
Is it true that a
person can lose considerable vision shortly
after laser treatment? Each case is different. In
patients with advanced diabetic retinopathy,
laser photocoagulation treatment is not as
effective as it is in patients with early
retinopathy. In many patients, the
progression of retinopathy is delayed. But
in others, the disease progresses despite
the laser treatment or, by coincidence, at
the same time as the treatment.
Should a person with
diabetic retinopathy exercise?
Studies have shown that most patients
with proliferative retinopathy have
hemorrhages at night while they sleep. There
is no convincing evidence that exercise
increases the number of hemorrhages.
Moreover, exercise is important not only for
general well-being, but also for controlling
blood sugar levels. Each patient should
continue routine exercise unless he or she
notices hemorrhages frequently during
exercise.
Why can�t I be given a
stronger prescription for glasses to
compensate for my vision loss?
If the retina is damaged, stronger glasses
cannot return distance vision to normal.
They do provide greater magnification, but
they also force a patient to hold reading
material closer to the face. Most patients
who have a moderate degree of vision loss
opt for a hand-held magnifier in addition to
normal reading glasses, allowing for a more
comfortable reading distance.
Some patients might be helped greatly by low
vision aids. These are special magnifying
devices that enable patients to make the
best use of their remaining eyesight by
enlarging objects so that they can be seen
with parts of the eye other than the macula.
For certain patients, telescopic devices
might improve distance vision. These aids
are available through your own
ophthalmologist
How can I prevent
further vision loss from retinopathy?
There is no evidence that limiting the use
of your eyes, avoiding television or bright
light, taking vitamins or using sunglasses
or any other devices can prevent diabetic
retinopathy or its progression.
What hope does the
future hold for patients with diabetic
retinopathy?
Research into the basic mechanisms of
retinopathy is ongoing. Doctors and
scientists continue to study how the retina
and choroid work and what changes occur
during the aging process.
Research is also under way on means to
control new blood vessel growth and blood
vessel leakage. Recent studies, still
awaiting confirmation, show that certain
antihypertensive medications (high blood
pressure drugs) may slow the development of
retinopathy.
Is there any financial
assistance available for people who have
lost vision? There is financial aid for people
whose best-corrected vision with glasses is
20/200 or worse, or whose visual field is
restricted to 10 degrees or less. They might
be eligible for an additional income tax
deduction as well as other financial and
rehabilitative benefits to help them cope
with vision loss. People with vision
slightly better than 20/200 might be
eligible for rehabilitative services.
What is retinal vein
occlusion?
Arteries carry blood from the heart to
various body parts, and veins return it. The
retina has one major artery and one major
vein, which is called the central retinal
vein. Sometimes, branches of this vein can
be blocked.
What causes retinal
vein occlusion?
In most cases, an underlying causes is not
found, and we never know why it happens.
However, retinal vein occlusion is more
common in patients with high blood pressure
and arteriosclerosis.
Why does retinal vein
occlusion cause decreased vision? What is
the likely visual outcome?
When the vein is blocked, the circulation is
greatly slowed. When this happens, the
retina (the part of the eye which sees, like
the film in a camera) does not work as well
as it should. In addition, tiny blood
vessels called capillaries leak excessive
fluid into the retina, causing it to swell.
This is called macular edema.
The ultimate visual outcome for patients
with retinal vein occlusion cannot be
predicted. About one-quarter of these
patients have spontaneous improvement in
vision, but in others, the vision remains
decreased or even worsens.
The only known way to improve vision for
patients with retinal vein occlusion is to
treat the swollen retina with laser. With
laser treatment, most patients have a small
improvement in vision. A small minority have
improvement to near normal. In many the
vision is not helped at all. However,
physicians normally wait a few months to see
if there is a spontaneous improvement before
considering laser treatment.
Are there any
restrictions or precautions for patients
with retinal vein occlusion?
There is no reason to limit one�s activities
(such as reading, watching TV, etc.).
However, when you have blurred vision in one
eye for any reason, your depth perception is
impaired. If this is true for you, you
should be very careful doing anything that
requires you to judge distances, such as
using machinery, climbing ladders, pouring
hot or hazardous liquids, or driving.
What is central
retinal vein occlusion?
Arteries carry blood from the heart to
various body parts, and veins return it. The
retina has one major artery and one major
vein, which is called the central retinal
vein. Sometimes the vein becomes blocked.
This is called central retinal vein
occlusion.
What causes central
retinal vein occlusion?
In most cases, there is no underlying cause
and doctors do not know why it happens.
However, it is more common in patients with
glaucoma, high blood pressure,
arteriosclerosis and diabetes.
What causes decreased
vision? What is the likely visual outcome?
What can be done to improve vision? When the retinal vein is blocked, the
circulation is greatly slowed. When this
happens, the part of the eye which sees
(like the film in a camera) does not work as
well as it should.
The ultimate visual outcome cannot be
predicted. A few patients, with time, have
spontaneous improvement in vision. Some
patients get worse. Currently, there is no
known way to improve vision. Laser, eye
drops and glasses will not help.
If there is no
treatment for central retinal vein
occlusion, why are follow-up visits
necessary? Although nothing can be done to help
their vision, patients who have had a
central retinal vein occlusion need to be
seen at regular intervals because in about
one-third of all cases, a severe form of
glaucoma, called neovascular glaucoma,
develops. If it looks like this is about to
occur, a laser treatment is necessary.
Though the laser does not improve vision, it
does prevent glaucoma from developing. Of
course, if there is any marked decrease in
vision or if the eye becomes painful, it is
important to see your doctor immediately.
Are there any
restrictions or precautions for patients
with central retinal vein occlusion? There is no reason to limit one�s
activities (such as reading, watching TV,
etc.). However, when you have blurred vision
in one eye for any reason, your depth
perception is impaired. If this is true for
you, you should be very careful doing
anything that requires you to judge
distances, such as using machinery, climbing
ladders, pouring hot or hazardous liquids,
or driving.
What happens during
macular translocation surgery? In order to move the retina, an
operation is performed. This can be
performed under local or general anesthesia.
There are three basic steps to this
operation.
First, the retina is intentionally detached
(the wall paper lifted off the wall) by
injecting fluid under the retina. Second,
several stitches are placed towards the back
of the eye to mildly indent the wall of the
eye. (These stitches are not visible
afterwards and remain permanent.) Third, an
air bubble is placed into the main cavity of
the eye. After surgery, patients are
instructed to sit upright for 24 to 48
hours. The air bubble, in combination with
the indentation of the wall of the eye,
pushes the retina back into position against
the back wall of the eye.
Although some variations with this technique
may be used depending on the specific
circumstances, these basic steps are
performed to achieve macular translocation.
The air bubble injected into the eye will be
gradually absorbed by the body within a few
days to weeks. In general, laser treatment
is performed as quickly as possible after
surgery (usually within one week) to the CNV.
What are the risks and
benefits of macular translocation surgery? It is impossible to predict exactly how
far the retina will shift as a result of
this surgery. If your doctor suggests
macular translocation surgery, he or she
believes there is a reasonable chance that
the retina will move far enough to safely
allow treatment of the CNV. Unfortunately,
in a minority of patients, there is no
sufficient movement of the retina.
There are risks associated with this
surgery. These include infection,
hemorrhage, cataract, glaucoma and retinal
detachment. Although many of these problems
are correctable, there is a small risk that
irreversible loss of vision could develop as
a result of this surgery. Macular
translocation surgery does not �cure�
macular degeneration. In some cases
successful closure of the CNV may only be
temporary and new blood vessels will grow.
If this occurs, then additional laser
surgery may be necessary. In some cases,
additional laser surgery may not be
possible. The long-term benefit of macular
translocation surgery is not known.
Preliminary results are encouraging, but not
every patient benefits from the procedure.
There is generally only mild-to-moderate
discomfort after this surgery, lasting
one-to-two weeks. Some restrictions in
activity beyond special positioning
requirements may be required. As a result of
moving the retina, some patients may
experience double vision, depending on the
quality of vision in the other eye. The
recovery of vision after surgery is quite
variable. Some patients require several
weeks or even months to fully assess their
visual recovery. This is often temporary. If
not, in some cases it may be possible to
correct visual impairments with eye glasses.
COPYRIGHT � 2014 APOLLO EYE INSTITUTE DR
MALLIKA GOYAL
