What Is Fluorescein Angiography?

Fluorescein angiography is a medical procedure used in the diagnosis of retinal problems. A dye is introduced into the bloodstream. When the dye reaches the blood vessels in the eye a series of flash photographs are taken. These pictures reveal the blood vessels in the retina of the eye as well as other abnormalities in the back of the eye, according to the Mayo Clinic.

The Dye

• Fluorescein dye in the bloodstream appears bright yellow in photographs. These photographs show the blood vessels, and any leaks, in high contrast to the rest of the retina.

The Procedure

• The pupil of the patient's eye is dilated to improve the view of the back of the eye. Initial pictures are taken to establish a baseline before the fluorescein dye is introduced by an intravenous injection. Photographs are taken every few seconds as the dye moves through the system. The photographs are usually interpreted by an ophthalmologist.

Side Effects

• The fluorescein injection can cause feelings of nausea and a brief warm sensation, according to the National Institute for Health. The symptoms are usually mild and brief. The eye dilation will cause reduced visual acuity for up to 12 hours. The patient should not drive until vision returns to normal.

Contraindications

• Patients with allergies to iodine may not be candidates for fluorescein angiography. Inform the doctor of any allergies before the test. Ophthalmologists may ask the patient to temporarily discontinue some drugs that interfere with the test. Patients are asked to sign a consent form before the procedure.

Results

• Normal results indicate the blood vessels in the back of the eye are of normal size with no leaks. Abnormal results can indicate a range of diseases including cancer, macular degeneration and diabetic retinopathy. The test can be repeated at intervals to track the changes in the blood vessels of the eye.