Diagnosis of pulmonary embolism (PE)

A doctor will make a diagnosis of PE using a similar approach to diagnosing a DVT. Step 1 involves asking questions, assessing clinical signs and then completing a clinical decision rule. Step 2 is performing a D-dimer test, and Step 3 involves imaging the lungs to see if a clot can be seen.

The following imaging tests are used to diagnose PE:

  • Spiral computed tomography (CT) scan. Doctors use this test to look for blood clots in the lungs and legs. Dye is injected into a vein to make the blood vessels visible on X-ray image. This test allows doctors to detect PE in most patients. The test only takes a few minutes. Results are available shortly after the scan is completed.
  • Ventilation–perfusion lung scan (VQ scan). Doctors use this test to detect PE. The VQ scan uses a radioactive material to show how well oxygen and blood are flowing to all areas of the lungs.