Lung Scan

A lung scan (or ventilation-perfusion scan), uses a radioactive substance (or tracer) to examine your lungs. A lung scan is performed to gain information about the airflow and blood flow in the lungs. It can help detect blood clots (pulmonary emboli), or other abnormalities.

Before Your Procedure

• Tell your physician if you are pregnant or nursing.
• You should have a chest X-ray done within 12-24 hours of performing the scan. No other preparation is required.

During Your Procedure

• You will first breathe for approximately 3-4 minutes on a machine that contains oxygen and a small amount of radioactivity. The radioactive gas will clear from your lungs as you breathe. The amount of radiation you receive is similar to a chest X-ray. This air mixture will show airflow into your lungs on a series of images.
• Next, you will have a radioactive substance (or tracer) injected into a vein in your arm. You will not feel any effects from the injection. The radioactive substance travels through the blood and eventually into your lungs.
• You may be asked to move into different positions so your lungs can be viewed from other angles.
• It is important to remain very still during the scans to avoid blurring the pictures.
• Total length of exam is about 1 hour.

After Your Procedure

• Your doctor will be contacted with the results of your test and will discuss the results with you.