If your ophthalmologist suspects an abnormality with your retina or choroid (the inside of the back of your eye), he or she may recommend special tests called fluorescein and/or indocyanine green (ICG) angiograms. What are fluorescein/ICG angiograms?
What are fluorescein/ICG angiograms?
Fluorescein/ICG angiograms are diagnostic procedures that involve taking a rapid series of photographs (not X-rays) of your eye while a small amount of dye (fluorescein or indocyanine green) is injected into a vein in your arm. The dye is carried by your blood stream throughout the whole body, reaching your eye in about 10 seconds. Photographs are taken at different intervals up to 30 minutes after the injection.
The photographs show what changes have taken place in the retina and choroid and where the changes are located. The two dyes allow visualization of structures within the eye and may or may not be used together, depending on what abnormality your ophthalmologist suspects.
A fluorescein and/or ICG angiogram may be necessary to establish a diagnosis or if your doctor feels that you may benefit from treatment. If you are going to be treated with a laser, the photographs provide a kind of “map” for the doctor to use during the treatment.
Note: Fluorescein and/or ICG angiography is often performed several times after treatment to evaluate the effectiveness of your therapy.
The fluorescein dye may make your skin yellowish for several hours after the procedures. The dye also discolors your urine bright yellow for a day or so.
Unlike fluorescein dye, indocyanine green contains 5% iodine; therefore, patients with iodine allergies may have reactions to ICG dye.
Fortunately, allergic reactions to either dye are rare and are usually treated with antihistamine medications. Although severe allergic reactions (anaphylaxis) can occur, these are considered extremely rare.
Note: Fluorescein/ICG angiography is generally not performed on patients who are pregnant or who have liver disease.
Or call 216.444.2020 or 1.800.223.2273 ext. 4-2020 to schedule an appointment with a Cole Eye Institute ophthalmologist.