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Lung Disease & Respiratory Health Center

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Lung Scan

How To Prepare

Before your lung scan, tell your doctor if:

  • You are or might be pregnant.
  • You are breast-feeding. The radioactive tracer used in this test can get into your breast milk. Do not breast-feed your baby for 1 or 2 days after this test. During this time, you can give your baby breast milk you stored before the test, or you can give formula. Discard the breast milk you pump for the 1 or 2 days after the test.

A chest X-ray is usually done the same day either before or after the lung scan.

You may be asked to sign a consent form.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

How It Is Done

A lung scan is usually done by a nuclear medicine technologist. The scan pictures are usually interpreted by a radiologist or nuclear medicine specialist.

You will need to remove any jewelry that might interfere with the scan. You may need to take off all or most of your clothes, depending on which area is being examined (you may be allowed to keep on your underwear if it does not interfere with the test). You will be given a cloth or paper covering to use during the test.

During the scan, you will either lie on your back with the scanning camera positioned over or under your chest, or you will sit with the camera positioned next to your chest. The camera does not produce any radiation, so you are not exposed to any more radiation while the scan is being done.

Ventilation scan

For the ventilation scan, a mask will be placed over your mouth and nose. Or you may have a nose clip on your nose and a tube in your mouth that you use for breathing. You will inhale the tracer gas or mist through the mask or tube by taking a deep breath and then holding it. The camera will scan for radiation released by the tracer and produce pictures as the tracer moves through your lungs. You may be asked to breathe the gas in and out through your mouth for several minutes. You may then be asked to hold your breath for short periods (about 10 seconds) and to change positions so your lungs can be viewed from other angles. The camera may move to take pictures from different angles. You need to remain very still during the scans to avoid blurring the pictures.

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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