Test Overview
An eye angiogram uses fluorescein dye and a camera to take pictures
and evaluate the blood flow through the vessels in the back of the eye (
retina
).
See a picture of the
structures of the eye
.
During an eye angiogram, the dye is injected
into a vein in your arm. Once injected, it takes about 10 to 15 seconds to
circulate through your body. As the dye enters the blood vessels in your eyes,
a series of photos are taken to chart the dye's progress. More pictures are
taken after most of the dye has passed through your eyes to see if any of it
has leaked out of the blood vessels. Any dye that leaks out of the blood
vessels will color the tissues and fluid in the eye. Filters in the camera
allow the areas colored by the dye to show up in the photos.
Unlike other
angiogram procedures, an eye angiogram is not an
X-ray procedure, so you are not exposed to any
radiation.
Why It Is Done
An eye angiogram is done to:
- Confirm the presence of abnormal blood vessels
in or under the retina.
- Check for and locate leaking blood vessels
in the retina, especially if you have symptoms that suggest damage to or
swelling of the retina, such as blurred or distorted vision. This is often
caused by
diabetic retinopathy
or
macular degeneration
.
- Help find
inflammation or tumors in the eye.
- Locate the precise areas of the
retina that need treatment prior to laser eye surgery.
- Help find
blockage in the blood vessels that feed or drain blood from the retina (retinal
arteries and veins).
How To Prepare
If you wear contact lenses, remove them
before the test. After the test, do not put soft contact lenses back in your
eyes for at least 4 hours because the contacts may become stained from the dye
used for the test.
Before the test, tell your doctor if
you:
- Have ever had an
allergic reaction
to X-ray
contrast materials
, iodine (which is present in
indocyanine green dye), fluorescein, or dilating eyedrops.
- Have a
history of
glaucoma, including
closed-angle glaucoma. You may need to delay doses of
certain eyedrops until after the test. The doctor also may not use dilating
eyedrops or may use different eyedrops before the test.
- Are taking
any prescription or over-the-counter medicines.
- Are or might be
pregnant or are breast-feeding. Most doctors discourage the use of this test
during pregnancy, especially during the first 3 months, and while a woman is
breast-feeding.
Talk to your doctor about any concerns you have regarding
the need for the test, its risks, how it will be done, or what the results may
mean. To help you understand the importance of this test, fill out the
medical test information form
(What is a
PDF
document?)
.
After the test:
- Your vision may be blurred for up to 12
hours.
- You should not drive until the effects of the dilating
eyedrops wear off. Arrange for someone to drive you home.
- You
should wear sunglasses until your
pupils
return to normal size. Bright light and
sunshine may hurt your eyes.
How It Is Done
An eye angiogram is done in a hospital
or doctor's office by an
ophthalmologist
.
Before the test, the
doctor uses drops to widen, or dilate, your pupils. You will be seated in a
chair facing the camera. You should loosen or remove any restrictive clothing
around your neck. You will be asked to place your chin on a chin rest and your
forehead against a bar to stabilize your head. Keep your teeth closed, open
your eyes as widely as you can, and stare straight ahead while breathing and
blinking normally. A few photographs will be taken.
An
IV
needle is then placed in a vein in your arm and the
dye is injected. Once injected, it takes about 10 to 15 seconds for the dye to
be visible in the blood vessels in your eyes.
As the dye enters
the eyes, the doctor takes a rapid series of photos for a few minutes. The
photos show the dye's progress through the blood vessels in your eyes. The dye
makes the blood vessels show up clearly in the photos. More photos are taken
after most of the dye has passed through the eyes to see whether any of the
blood vessels are leaking the dye. If dye leaks out of a blood vessel, it will
color the surrounding tissue and fluid in the eye.
The test
usually takes about 30 minutes, unless additional photos are needed. If more
photos are needed, you will rest for 20 minutes before 5 to 10 more photos are
taken. Photos can be taken up to 1 hour after an injection.
How It Feels
When fluorescein dye is injected into
your arm, you may notice a metallic taste in your mouth, mild nausea, and a
brief sensation of warmth.
After the test, your skin, the whites
of your eyes, and your urine may be bright yellow or orange, but these effects
wear off in 24 to 48 hours.
Because of the dilating eyedrops,
your vision may be blurred, and your eyes may be sensitive to light for up to
12 hours. Avoid bright light and sunshine. Wear dark glasses when you go
outside.
Risks
While the fluorescein dye is injected, you may
become nauseated and feel flushed. These symptoms pass quickly.
Some people are allergic to the dye. Tell your doctor if you feel lightheaded, need to vomit, or have
itching and
hives
after the dye is injected. Very rarely, a person may have a serious allergic
reaction (
anaphylaxis
) and need emergency care.
Dye that
leaks out of the vein around the injection site may cause pain and may injure
the skin.
The dye may pose a risk to a
fetus
. If you are pregnant, talk to your doctor about
these risks.
Results
An
eye angiogram
uses fluorescein or indocyanine dye and
a camera to take pictures and evaluate the blood flow through the vessels in
the back of the eye (
retina
).
This test takes
about 30 minutes. Your doctor can usually review the results soon after.
Eye angiogram
| Normal: |
- The dye flows through the blood vessels
in the
retina
without delays.
- There are no leaks or areas of
blockages.
|
| Abnormal: |
- The dye flows very slowly through the
blood vessels.
- The flow of dye is blocked.
- The dye
leaks from the blood vessels.
- The dye pools in the surrounding eye
tissue or in the
optic disc
.
|
Many conditions can change eye angiogram results. Your
doctor will discuss any significant abnormal results with you in relation to
your symptoms and past health.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
-
Cataracts
.
- Inadequate dilation of the
pupils
.
- Inability to keep your eyes wide
open and to stare straight ahead during the test.
What To Think About
- Most doctors discourage the use of this test
during pregnancy—especially during the first 3 months.
- Since the
dye passes to your baby in breast milk, it is not safe to
breast-feed
for 24 to 48 hours after this test. Use a
breast pump to empty your breasts and discard the milk until it is safe to
start breast-feeding again. You may wish to collect and store breast milk for
several days before the test or purchase formula to use during this
time.
- The dye is filtered through your kidneys and passes out of
your body in your urine within about 48 hours. Your urine may be bright yellow
or orange during this time.
- A dye called indocyanine green is better at finding some types of
eye problems and may be used instead of fluorescein. It allows the doctor to
see whether blood vessels underneath the
retina are leaking.
References
Other Works Consulted
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis:
Saunders.
- Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
Credits
|
By
| Healthwise Staff |
|
Primary Medical Reviewer
| Kathleen Romito, MD - Family Medicine |
|
Specialist Medical Reviewer
| Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology |
|
Last Revised
| August 20, 2012 |
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