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 injury or other damages that could
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