A pulmonary ventilation/perfusion scan involves two nuclear scan tests. These tests use inhaled and injected radioactive material (radioisotopes) to measure breathing (ventilation) and circulation (perfusion) in all areas of the lungs.

V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan

A pulmonary ventilation/perfusion scan is actually two tests. These tests may be performed separately or together.

During the perfusion scan, a health care provider injects radioactive albumin into your vein. You are placed on a movable table that is under the arm of a scanner. The machine scans your lungs as blood flows through them to find the location of the radioactive particles.

During the ventilation scan, you breathe in radioactive gas through a mask while you are sitting or lying on a table under the scanner arm.

You do not need to stop eating (fast), eat a special diet, or take any medications before the test.

A chest x-ray is usually done before or after a ventilation and perfusion scan.

You will sign a consent form and wear a hospital gown or comfortable clothing that does not have metal fasteners.

The table may feel hard or cold. You may feel a sharp prick while the material is injected into the vein for the perfusion part of the scan.

The mask used during the ventilation scan may make you feel nervous about being in a small space (claustrophobia). You must lie still during the scan.

The radioisotope injection usually does not cause discomfort.

The ventilation scan is used to see how well air and blood flow moves through the lungs. The perfusion scan measures the blood supply through the lungs.

A ventilation and perfusion scan is most often done to detect a pulmonary embolus (blood clot in the lungs). It is also used to:

• Detect abnormal circulation (shunts) in the blood vessels of the lungs (pulmonary vessels)
• Test lung function in people with advanced pulmonary disease, such as COPD

Images

Albumin injection

Next Section

Pulmonary ventilation/perfusion scan Results

Review Date: 09/15/2010
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)