Diabetic
Retinopathy
Overview
Diabetes is a
disease that occurs when the pancreas does not
secrete enough insulin or the body is unable
to process it properly.
Insulin is the hormone that regulates
the level of sugar (glucose) in the blood.
Diabetes can affect children and
adults.
How does
diabetes affect the retina?
Patients with
diabetes are more likely to develop eye
problems such as cataracts
and glaucoma,
but
the disease’s affect on the retina
is the main threat to vision.
Most patients develop diabetic changes
in the retina after approximately 20 years.
The effect of diabetes on the eye is
called diabetic retinopathy.
Over time,
diabetes affects the circulatory system of the
retina. The
earliest phase of the disease is known as
background diabetic retinopathy.
In this phase, the arteries in the
retina become weakened and leak, forming
small, dot-like hemorrhages.
These leaking vessels often lead to
swelling or edema in the retina and decreased
vision.
The next
stage is known as proliferative diabetic
retinopathy.
In this stage, circulation problems
cause areas of the retina to become
oxygen-deprived or ischemic.
New, fragile, vessels develop as the
circulatory system attempts to maintain
adequate oxygen levels within the retina.
This is called neovascularization.
Unfortunately, these delicate vessels
hemorrhage easily.
Blood may leak into the retina and vitreous,
causing spots or floaters,
along with decreased vision.
In the later
phases of the disease, continued abnormal
vessel growth and scar tissue may cause
serious problems such as retinal
detachment and glaucoma.
Illustration
by Mark Erickson
Signs and Symptoms
The
affect of diabetic retinopathy on vision
varies widely, depending on the stage of the
disease.
Some common symptoms of diabetic
retinopathy are listed below, however,
diabetes may cause other eye symptoms.
Detection and Diagnosis
Diabetic
patients require routine eye examinations so
related eye problems can be detected and
treated as early as possible.
Most diabetic patients are frequently
examined by an internist or endocrinologist
who in turn work closely with the
ophthalmologist.
The
diagnosis of diabetic retinopathy is made
following a detailed examination of the retina
with an ophthalmoscope.
Most patients with diabetic retinopathy
are referred to vitreo-retinal surgeons who
specialize in treating this disease.
Treatment
Diabetic
retinopathy is treated in many ways depending
on the stage of the disease and the specific
problem that requires attention.
The retinal surgeon relies on several
tests to monitor the progression of the
disease and to make decisions for the
appropriate treatment.
These include:
fluorescein
angiography, retinal
photography, and ultrasound imaging of the
eye.
The abnormal
growth of tiny blood vessels and the
associated complication of bleeding is one of
the most common problems treated by vitreo-retinal
surgeons.
Laser surgery called pan retinal
photocoagulation (PRP) is usually the
treatment of choice for this problem.
With
PRP, the
surgeon uses laser to destroy oxygen-deprived
retinal tissue outside of the patient’s
central vision.
While this creates blind spots in the
peripheral vision, PRP prevents the continued
growth of the fragile vessels and seals the
leaking ones.
The goal of the treatment is to arrest
the progression of the disease.
Vitrectomy
is another surgery commonly needed for
diabetic patients who suffer a vitreous
hemorrhage (bleeding in the gel-like substance
that fills the center of the eye).
During a vitrectomy, the retina surgeon
carefully removes blood and vitreous from the
eye, and replaces it with clear salt solution
(saline).
At the same time, the surgeon may also
gently cut strands of vitreous attached to the
retina that create traction and could lead to
retinal detachment or tears.
Patients with
diabetes are at greater risk of developing
retinal tears and detachment.
Tears are often sealed with laser
surgery.
Retinal detachment requires surgical
treatment to reattach the retina to the back
of the eye.
The prognosis for visual recovery is
dependent on the severity of the detachment.
Prevention
Researchers
have found that diabetic patients who are able
to maintain appropriate blood sugar levels
have fewer eye problems than those with poor
control.
Diet and exercise play important roles
in the overall health of those with diabetes.
Diabetics can
also greatly reduce the possibilities of eye
complications by scheduling routine
examinations with an ophthalmologist.
Many problems can be treated with much
greater success when caught early.
About
our Retinal Specialists
More
about Diabetes Control
More
about vitrectomy
St.
Luke's Cataract & Laser Institute
provides this on-line information for
educational and communication purposes only
and it should not be construed as personal
medical advice. Information published on
this St. Luke's website is not intended to
replace, supplant, or augment a consultation
with an eye care professional regarding the
viewer/user's own medical care. St.
Luke's disclaims any and all liability for
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