What is Fluorescein Angiography?
Fluorescein angiography is a diagnostic technique ophthalmologists use to closely examine the blood vessels and flow pattern at the back of your eye. A colored dye is injected into a vein in your arm, where it then makes its way through the body and up to the smaller vessels of your eye. From there, a special camera takes a series of photos to capture how and when the blood vessels receive blood.
What is it Used For?
Fluorescein angiography is used to help your ophthalmologist see what is happening in the retinal and choroidal vasculature at the back of your eye. The retina is a small thin nerve layer that detects light, and receives nutrients and oxygen from very small blood vessels. The choroid lies directly underneath the retina, and also has many blood vessels to help nourish the eye. It is sight threatening if there is a problem with the eye’s circulation, such as a blockage, leak, or new vessel formation, and fluorescein angiography can help detect this by highlighting any abnormalities. It is most often used to:
- Help diagnose & monitor eye conditions such as…
- Macular degeneration
- Diabetic retinopathy
- Retinal vein occlusion
- Macular edema
- Guide laser surgery
- Monitor the effect of laser surgery
How Fluorescein Angiography Works
- Special drops to widen your pupil are instilled – this helps the photographer see a large view of the back of your eye during the procedure. After about 20-30 minutes, your pupils should be fully dilated.
- You will receive an injection of the fluorescein dye in your forearm.
- The dye will then pass through the retinal and choroidal blood vessels, and a series of photos are taken. You will see many quick bursts of light, but it is important to try and keep your eyes wide open. The process takes about 30 minutes.
Before the procedure, it is important to alert the medical team of any conditions such as severe allergies, a kidney disorder, asthma, bronchitis, heart disease, if you are pregnant or nursing, or if you have a previous history of nausea, vomiting, or skin reactions.
Side Effects of Fluorescein Angiography
Some possible side effects to be aware of:
- There may be a burning sensation if the dye leaks from your vein anywhere.
- Have enlarged pupils makes your eyes sensitive to light. Make sure to bring sunglasses with you to your appointment.
- Your vision may also be blurry from the dilating drops. Make sure to arrange for a ride home after the procedure.
- Your vision may appear darker/have a colored tint for a couple minutes afterwards.
- Your skin may turn yellowish for several hours due to the fluorescein dye.
- Your urine will turn dark orange or yellow up to 24 hours following the test because your kidneys help remove the dye from your blood.
- 5% of people may have reactions to the dye such as nausea, vomiting, itching, or mild skin irritations around the injection site.
- Some may feel faint or have an elevated body temperature.
- Severe or life threatening respiratory, cardiac or neurological reactions may rarely occur. These would require immediate medical treatment.