What is Fluorescein Angiography?
Fluorescein is a non-toxic orange dye. In this test, the dye is injected into your bloodstream via a small vein in your hand or arm. A series of photographs of the back of your eye are then taken.
Why is this procedure necessary?
This procedure enables the doctor to examine the small blood vessels at the back of the eye. It can diagnose areas of poor blood supply, leakage from blood vessels, and abnormal new vessels. In this way, it can help in providing a diagnosis and planning for treatment.
Are there any alternatives?
Whilst we can look at the back of your eye with a microscope (clinical examination), this dye test is the only effective way of examining the integrity of blood vessels within the eye.
Should I eat and drink before the procedure?
It is advisable to eat a light meal before the procedure and diabetic patients are advised to ensure that sufficient food has been taken. There is no need to restrict drinks.
Should I take my normal medication?
- Please inform medical and nursing staff of any medication that you use.
- Take all your medications as normal, but avoid eye ointments until after the procedure as they are greasy and affect image quality in the test.
How is the test performed?
You may be asked some questions about your general health and any treatment that you may be taking or have taken in the past. You may be asked to sign a consent form. Please inform the nurse if you have any known allergies (including food allergies), have had any side effects from a previous Fluorescein Angiography test, or you are pregnant or breastfeeding. Your pupils will be dilated (made bigger) with eye drops which take approximately 30 minutes to work. A small cannula will be passed into a vein in your hand or arm, through which the Fluorescein dye will be injected. A series of photographs are taken as the dye enters the blood vessels at the back of the eye. It is important to keep still during the procedure so that the best images can be taken. If you are not comfortable at the camera, tell the nurse before the dye is injected so that your position can be adjusted optimally.
When can I go home after the procedure?
Following the procedure you will be asked to remain in the department for around half an hour.
Are there any side effects or risks to the procedure?
All procedures, no matter how big or small, carry a risk.
- During the procedure you may feel warm or experience a ‘hot flush’. This usually occurs in the first minute and then subsides.
- Your skin may be tinged with yellow, and your urine and tears may be discoloured yellow for 24 hours after the procedure. This is normal and wears off as the dye leaves your body.
- Occasionally more severe symptoms may occur. You may feel nauseous, a few people experience vomiting, and some people feel faint, but this does not last long.
- Approximately one patient in every 20,000 will experience a moderate to severe allergic reaction known as Anaphylactic Shock (collapse and, or severe breathlessness).
- The dye is not radioactive – no radiation is involved in this test.
Can my optician or optometrist do this test?
No. Fluorescein angiography is ordered, and interpreted, by an ophthalmic surgeon.
Will it improve my vision?
The procedure itself will not improve or indeed affect your vision whatsoever. However the dilating drops and the bright light of the camera may blur your vision for a few hours.
Following the procedure
- Drink plenty of fluids
- Do not sit in strong sunshine for 24 hours after the test.
- If you are having a blood test within 48 hours after the test, please inform the doctor requesting those blood tests that you have had fluorescein angiography.
- Your urine will be yellow-orange for up to 24 hours – this is the dye leaving your body.
- Please drink plenty of fluids following the test.
When will I get the results of my test?
A follow-up appointment will be made for you to discuss the results with your ophthalmologist. Alternatively, if the test indicates that you require treatment, this may be scheduled for you straight away.
Can I drive home?
You will not be able to drive home or use a mobility scooter after your procedure. This is because of the drops. Please bring a companion, or make suitable transport arrangements, so you can get home afterwards. You may resume driving the day after your procedure when your vision has returned to normal.