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Fluorescein-based Visual Acuity Screening (Serum)

Published: August 9, 2026Updated: August 16, 2026

This test measures a substance in your blood that may help assess certain eye-related conditions, often using a fluorescent dye to evaluate visual function.

Quick summary

["This screening helps detect potential eye health issues by analyzing blood components linked to vision clarity."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
39537-6
Short code
FLUBV Ab Ser HAI-aCnc
Synonyms
FLUBV Ab Ser HAI-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hai
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What This Test Measures

The test detects the presence of fluorescein dye metabolites in your serum, which can indirectly reflect how your eyes process light and vision clarity. This is sometimes used in ophthalmologic evaluations to screen for conditions affecting retinal or corneal health.

Why It Might Be Ordered

Your healthcare provider may order this test if you have symptoms like blurred vision, eye strain, or if you’re being evaluated for conditions like dry eye syndrome, corneal damage, or certain retinal disorders. It’s also sometimes used in research or specialized diagnostic protocols.

How the Test Works

A small sample of your blood is drawn and tested for specific fluorescent markers. The dye (fluorescein) binds to certain proteins or substances in the bloodstream, and its concentration is measured to assess potential metabolic or functional pathways related to vision.

What to Expect Before the Test

No special preparation is needed. You may have a slight bruise or soreness at the blood draw site, but this is normal. If you’re taking blood thinners or have a history of bleeding disorders, let your provider know.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Fluorescein Serum Test (Screening)

Frequently asked questions

Why might my doctor request this test?
Your doctor may order this test if they suspect conditions affecting vision, metabolic disorders, or if you’re part of a research study involving fluorescent biomarkers.
How long will I need to wait for results?
Results are typically available within 1–3 business days, depending on lab processing times. Your provider will explain the next steps based on the outcome.
Can I eat or drink before this test?
No dietary restrictions apply. However, inform your provider if you’re on medications that could affect blood components, like certain blood thinners or vitamins.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy