Mismatched air and blood flow suggesting pulmonary embolism.
General health information, not a diagnosis. In an emergency, call 102. Always consult a qualified health professional.
A Ventilation-perfusion (V/Q) scan is a diagnostic imaging test used to assess blood flow and air distribution in the lungs. It helps identify conditions such as pulmonary embolism, where blood clots obstruct the flow of blood in the lungs. The test involves injecting a small amount of radioactive tracer into the bloodstream or swallowing it, which allows healthcare providers to observe the flow of air and blood in the lungs. The effectiveness of the test is measured by the typical effective dose, which is about 1 to 2 mSv, similar to the natural background radiation received over 4 to 8 months. The test results must be interpreted by a qualified health worker and should be considered alongside other diagnostic findings.
Mismatched air and blood flow suggesting pulmonary embolism.
Suspected PE when CT contrast is unsuitable (for example in pregnancy).
A small radioactive tracer is injected or swallowed. Preparation depends on the test; tell staff if pregnant or breastfeeding, as feeding may need a pause.
Typical effective dose 1 to 2 mSv, similar to about 4 to 8 months of natural background radiation (about 3 mSv a year). Tell staff if you are or might be pregnant; the benefit usually outweighs the small risk, and shielding or alternatives can be considered.
about 1 hour. General information, not a diagnosis. Results must be interpreted by a qualified health worker.
Consult a doctor to interpret results — a single test does not make a diagnosis.
Uses your location once to list the nearest facilities. Nothing is stored.
Why is Ventilation-perfusion (V/Q) scan done?
Suspected PE when CT contrast is unsuitable (for example in pregnancy).
How do I prepare for Ventilation-perfusion (V/Q) scan?
A small radioactive tracer is injected or swallowed. Preparation depends on the test; tell staff if pregnant or breastfeeding, as feeding may need a pause.
Is Ventilation-perfusion (V/Q) scan safe in pregnancy?
Typical effective dose 1 to 2 mSv, similar to about 4 to 8 months of natural background radiation (about 3 mSv a year). Tell staff if you are or might be pregnant; the benefit usually outweighs the small risk, and shielding or alternatives can be considered.
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