Diabetic retinopathy can have serious complications for a person’s sight if untreated. To help detect the condition, an eye doctor may perform a technique called fluorescein angiography to examine blood vessels in the eye.
Ophthalmologists can use fluorescein angiography (FA) to manage or check for eye conditions such as diabetic retinopathy (DR). During the procedure, an eye doctor injects fluorescent dye into a person’s bloodstream. The dye highlights blood vessels at the back of the eye, allowing the doctor to check blood vessels and the structure of the eye.
DR is a
Early diagnosis can help
This article discusses FA and how medical professionals use it to detect DR.
Ophthalmologists can use FA to:
- find and help diagnose eye conditions, such as DR
- track changes in eye conditions over time
- target areas of a person’s eye for treatment
Ophthalmologists may use FA to help diagnose other eye conditions apart from DR, such as:
- macular edema
- age-related macular degeneration (AMD)
- macular pucker
- ocular melanoma
- central or branch retinal vein occlusions
The procedure takes less than 30 minutes. Medical professionals recommend that people fast for 2–4 hours before their procedure. A person should also inform the ophthalmologist if they have any
Ophthalmologists use eye drops that dilate, or widen, the pupils of a person’s eye during FA. Therefore, they also recommend that people do not drive themselves to and from the appointment and wear sunglasses after the procedure.
Medical professionals will also review a person’s medical history before starting the procedure. If a person is
Ophthalmologists use a special camera for the FA procedure. A person sits in front of the camera and rests their head on chin and forehead supports. This keeps their head still during the FA.
Ophthalmologists prepare a person for FA by:
- asking them to remove any contact lenses
- putting drops in their eyes to widen their pupils
- injecting yellow sodium fluorescein dye into one of their veins, usually in their arm
- waiting 10–15 seconds for the dye to travel through their body to their eyes
The fluorescein dye allows clear observation of the blood vessels in the eye. A technician will then take photographs of a person’s eye to enable an eye doctor to interpret the results and see any problems or where to focus treatment.
People may experience some side effects after FA, such as:
- objects seeming dark or tinted for a few minutes
- a burning skin sensation for a few minutes as the ophthalmologist injects the dye
- skin that looks a different color for a few hours due to the dye
- blurry vision and light sensitivity for several hours due to the dilating eye drops
- urine that looks orange or dark yellow for up to 24 hours afterward
- itchy skin
- breathing issues or other problems in very rare cases
Ophthalmologists also prepare standard emergency equipment to manage allergic reactions before starting the procedure. They will treat any allergic reactions with pills or injectable medication.
Ophthalmologists may use other tests to help diagnose a person’s DR,
Dilated eye exams
During an eye exam, ophthalmologists put eye drops in a person’s eyes to widen their pupils. They then use a specialized lens to check the back of their eyes. This is usually the first test an ophthalmologist uses to check for DR.
Optical coherence tomography (OCT)
Ophthalmologists use an OCT machine to scan a person’s retina using light waves. This provides a detailed scan of the thickness of each layer of the retina. This helps ophthalmologists find and measure swelling of a person’s macula, a key part of their retina.
Ophthalmologists can use FA to detect, diagnose, and target treatment for DR. They usually use this technique alongside other tests, such as dilated eye exams.
Untreated DR can cause people to lose some or all of their vision over time. However, early diagnosis and treatment can help prevent vision loss. As such, ophthalmologists recommend people living with diabetes have yearly exam exams to assess eye health and detect early signs of DR.