V/Q Scan
Reviewed
A V/Q scan consists of two imaging tests that look for certain lung problems. A ventilation scan measures how air moves in and out of your lungs. A perfusion scan measures circulation (how blood flows in the lungs). The scans help diagnose different lung conditions, but they are most often used to check for a pulmonary embolism (PE).
Preparation and collection
A chest x-ray is usually done before a V/Q scan.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- The scan uses a small amount of radioactive tracer; radiation exposure is very low and leaves the body within a few days.
- The tracer may be harmful to a developing baby; tell your provider if you are pregnant or think you may be pregnant.
- The tracer may contaminate breast milk; tell your provider if you are breastfeeding.
- Allergic reactions to the tracer are rare and usually mild.
- Results should be interpreted by your healthcare provider; the source does not provide specific reference intervals or units.
What to do next
If you have questions about your results, talk to your provider. If diagnosed with a pulmonary embolism, treatment may include blood thinners, clot busters, or surgical procedures.