Fluorescein Angiography

Synonym/Acronym

ocular angiography, FA, FFA, fundus fluorescein angiography, OCT.

Rationale

To assist in detecting vascular changes in the eyes affecting vision related to diseases such as diabetic retinopathy and macular degeneration.

Patient Preparation

There are no food, fluid, or activity restrictions unless by medical direction. Instruct the patient to avoid eye medications (particularly miotic eye drops, which may constrict the pupil, preventing a clear view of the fundus, and mydriatic eye drops in order to avoid instigation of an acute open-angle attack in patients with narrow-angle glaucoma) for at least 1 day prior to the test. Patients with blue or hazel eye color have the option of requesting dilating drops with a lower concentration than standard drops, as blue or hazel eyes dilate faster than brown eyes and will remain dilated for a longer period of time. Ensure that the patient understands that they must refrain from driving until the pupils return to normal (about 4 hr) after the test and has made arrangements to have someone else be responsible for transportation after the test.

Normal Findings

No leakage of dye from retinal blood vessels
Normal retina and retinal and choroidal vessels
No evidence of vascular abnormalities, such as hemorrhage, retinopathy, aneurysms, or obstructions caused by stenosis and resulting in collateral circulation.

Critical Findings and Potential Interventions ⬆ ⬇

Overview ⬆ ⬇

(Study type: Sensory (ocular); related body system: Nervous system.)

Ocular imaging is a valuable tool for diagnosing eye diseases and disorders. There are two main imaging techniques used to identify abnormalities in eye structure and function: FA and OCT. FA is invasive and requires dilation prior to imaging; OCT is noninvasive and can be performed with or without dilation. The ophthalmologist will determine whether dilation will be needed and which study will be used as each method has its strengths and weaknesses.

Fluorescein angiography involves the color radiographic examination of the retinal vasculature following rapid IV injection of a sodium fluorescein contrast medium. A special camera allows images to be taken in sequence and manipulated by a computer to provide views of the retinal vessels during filling and emptying of the dye. The camera allows only light waves in the blue range to strike the fundus of the eye. When the fluorescein reaches the blood vessels in the eye, blue light excites the dye molecules to a higher state of activity and causes them to emit a greenish-yellow fluorescence that is recorded.

Optical coherence tomography is an imaging technique that uses light waves to create high-resolution, cross-sectional pictures of the anatomical structures at the back of the eye, namely the retina, retinal nerve fiber layer, and optic nerve head. A beam of light is used to scan an area of the patient’s eye. Light reflected back from the structures of the eye is measured and recorded as three-dimensional, cross-sectional images of the retina. Adaptive optics (AO) is a new, improved imaging technique, based on optical coherence tomography, that in combination with artificial intelligence (AI) is reported to be 100 times faster and able to provide images that are 3.5–fold better in quality. The improved technology will eventually enable health care providers (HCPs) to identify and evaluate very early development of age-related macular degeneration (AMD) and other retinal diseases.

Indications ⬆ ⬇

Detect arterial or venous occlusion evidenced by the reduced, delayed, or absent flow of the contrast medium through the vessels or possible vessel leakage of the medium.
Detect possible vascular disorders affecting visual acuity.
Detect presence of microaneurysms caused by hypertensive retinopathy.
Detect the presence of tumors, retinal edema, or inflammation, as evidenced by abnormal patterns or degree of fluorescence.
Diagnose and manage diabetic retinopathy. For additional information regarding screening guidelines and management of diabetes, refer to the study titled “Glucose.”
Diagnose past reduced flow or patency of the vascular circulation of the retina, as evidenced by neovascularization.
Diagnose presence of macular degeneration and any other degeneration and any associated hemorrhaging.
Observe ocular effects resulting from the long-term use of high-risk medications.

Contraindications ⬆ ⬇

Patients with a past history of hypersensitivity to radiographic dyes. Address concerns about nausea and vomiting, as appropriate.

Patients with narrow-angle glaucoma if pupil dilation is performed; dilation can initiate a severe and sight-threatening open-angle attack.

Patients with allergies to mydriatics if pupil dilation using mydriatics is performed.

Interfering Factors ⬆ ⬇

Presence of cataracts may interfere with fundal view.
Ineffective dilation of the pupils may impair clear imaging.

Other Considerations

Allergic reaction to radiographic dye, including nausea and vomiting, may interrupt the procedure.

Potential Medical Diagnosis: Clinical Significance of Results ⬆ ⬇

Abnormal Findings Related to

Aneurysm
Arteriovenous shunts
Diabetic retinopathy
Macular degeneration
Neovascularization
Obstructive disorders of the arteries or veins that lead to collateral circulation
Ocular histoplasmosis
Retinal vascular occlusion

Nursing Implications ⬆

Before the Study: Planning and Implementation

Teaching the Patient What to Expect

Review the procedure with the patient.
Discuss how this procedure can assist in detecting changes in the eye that affect vision. It may also be used as a preoperative assessment tool prior to retinal laser procedures.
Explain that for the OCT procedure, there are no special instructions.

Explain that prior to the procedure, laboratory testing may be required to assess for impaired kidney function (creatinine level and estimated glomerular filtration rate). The effects of fluorescein sodium on kidney function are not well understood, and the HCP may choose to assess kidney function if warranted.
Explain that the procedure can take up to 60 min to dilate and evaluate both eyes and is performed in a quiet, darkened room. Advise that there may be a brief stinging sensation when the dilating drop is put in the eye.
Discuss that some discomfort may be experienced during the insertion of the IV to allow intermittent infusion of dye. When fluorescein dye is injected, it may cause facial flushing or nausea and vomiting.

FA Procedural Information

The patient is instructed to remove contact lenses or glasses, as appropriate, and reminded that it is important to keep the eyes open and fixated for the test.
The patient is advised that mydriatics, if used, may cause blurred vision and sensitivity to light. There may be a brief stinging sensation when the drop is put in the eye.
The ordered mydriatic is administered to each eye if dilation is to be performed. Remind the patient that the dilating effects of ordered mydriatic drops may last up to 4 to 6 hr.
Positioning for this position is seated in a chair that faces the camera. The patient is instructed to look at a directed target while the eyes are examined.
An intermittent infusion device is inserted for subsequent injection of the contrast media or emergency medications.
After the eye drops are administered but before the dye is injected, color fundus photographs are taken.
The patient is instructed to place the chin in the chin rest and gently press the forehead against the support bar, open both eyes wide, and look at the desired target.
Fluorescein dye is injected into the brachial vein using the intermittent infusion device, and a rapid sequence of photographs is taken and repeated after the dye has reached the retinal vascular system. Follow-up photographs are taken in 20 to 30 min.
At the conclusion of the procedure, the IV is removed and direct pressure is applied with a dry gauze to stop bleeding. The venipuncture site is observed for bleeding or hematoma formation.
Once the examination is completed, the patient is advised to gently rinse the face, especially eyelids and corners of the eye to remove any crystallized residue of the dilation drops, if used. Gentle rinsing and drying by dabbing without rubbing is crucial to avoid causing a corneal abrasion. Rinsing helps decrease the time the eyes remain dilated by removing residue that otherwise would be washed back into the eye when the patient blinks.

OCT Procedural Information

Positioning for this position is seated in a chair that faces the camera. The patient is instructed to look at a directed target while the eyes are examined.
The patient is instructed to place the chin in the chin rest and gently press the forehead against the support bar, open both eyes wide, and look at the desired target.
Once the examination is completed, the patient is advised to gently rinse the face, especially eyelids and corners of the eye to remove any crystallized residue of the dilation drops, if used. Gentle rinsing and drying by dabbing without rubbing is crucial to avoid causing a corneal abrasion. Rinsing helps decrease the time the eyes remain dilated by removing residue that otherwise would be washed back into the eye when the patient blinks.

Potential Nursing Actions

Investigate the patient’s known or suspected vision loss; changes in visual acuity, including type and cause; use of glasses or contact lenses; and eye conditions with treatment regimens.

Make sure a written and informed consent has been signed prior to the procedure and before administering any medications.

Safety Considerations

Ensure that the patient understands that they must refrain from driving until the pupils return to normal (about 4 hr) after the test.
Ensure that arrangements were made to have someone else be responsible for patient transportation after the test.

After the Study: Implementation & Evaluation Potential Nursing Actions

Avoiding Complications

Monitor the patient for complications related to the procedure.
Observe for hypersensitive reaction to the dye. Anaphylaxis, bronchospasm, cardiac arrest, laryngeal edema, myocardial infarction, nausea, pruritus, urticaria, or vomiting can occur in response to the dye, and extravasation of the dye can occur during injection.
Dilation can initiate a severe and sight-threatening open-angle attack in patients with narrow-angle glaucoma if pupil dilation is performed.

Treatment Considerations

Follow postprocedure vital sign and assessment protocol.
Explain that visual acuity and responses to light may change. Suggest wearing dark glasses after the dilated test until the pupils return to normal size. Note that after the FA, yellow discoloration of the skin and urine from the radiographic dye are normally present for up to 2 days.

Nutritional Considerations

Abnormal findings may be associated with diabetes.
Discuss the nutritional management of diabetes.
There is no “diabetic diet”; however, many meal-planning approaches with nutritional goals are endorsed by the American Diabetes Association.
Patients who adhere to dietary recommendations report a better general feeling of health, better weight management, greater management of glucose and lipid values, and improved use of insulin. Variety in dietary patterns is beneficial for people with diabetes.
Encourage consultation with a registered dietitian who is a certified diabetes educator.

Clinical Judgement

Consider ways to get acceptance of the necessary dietary changes associated with diabetes to support visual health.

Follow-Up Evaluation and Desired Outcomes

Accepts that vision loss may impair independent activity and precipitate the loss of driving privileges.
Acknowledges contact information regarding vision aids provided for the American Heart Association (www.heart.org/HEARTORG), American Macular Degeneration Foundation (www.macular.org), Glaucoma Research Foundation (www.glaucoma .org), American Diabetes Association (www.diabetes.org), National Heart, Lung, and Blood Institute (www.nhlbi .nih.gov), or the U.S. Department of Agriculture’s resource for nutrition (www.myplate.gov).

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