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Ultrasound

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Illustrations

Abdominal ultrasound
Abdominal ultrasound
Ultrasound in pregnancy
Ultrasound in pregnancy
17 week ultrasound
17 week ultrasound
30 week ultrasound
30 week ultrasound
Carotid duplex
Carotid duplex
Ultrasound comparison
Ultrasound comparison
Thyroid ultrasound
Thyroid ultrasound
Ultrasound
Ultrasound
Ultrasound, normal fetus- ventricles of brain
Ultrasound, normal fetus- ventricles of brain

Alternative Names    Return to top

Sonogram

Definition    Return to top

Ultrasound involves the use of high-frequency sound waves to create images of organs and systems within the body.

How the Test is Performed    Return to top

An ultrasound machine creates images that allow various organs in the body to be examined. The machine sends out high-frequency sound waves, which reflect off body structures. A computer receives these reflected waves and uses them to create a picture. Unlike with an x-ray, there is no ionizing radiation exposure with this test.

The test is done in the ultrasound or radiology department. You will be lying down for the procedure. A clear, water-based conducting gel is applied to the skin over the area being examined to help with the transmission of the sound waves. A handheld probe called a transducer is then moved over the area being examined. You may be asked to change position so that other areas can be examined.

For specific information about ultrasound examinations, please refer to the following topics:

How to Prepare for the Test    Return to top

Preparation for the procedure will depend on the body region being examined.

How the Test Will Feel    Return to top

There is generally little discomfort with ultrasound procedures. The conducting gel may feel slightly cold and wet.

Why the Test is Performed    Return to top

The reason for the examination will depend on your symptoms.

Normal Results    Return to top

Results are considered normal if the organs and structures in the region being examined are normal in appearance.

What Abnormal Results Mean    Return to top

The significance of abnormal results will depend on the body region being examined and the nature of the problem. Consult your health care provider with any questions and concerns.

Risks    Return to top

There are no documented risks. No ionizing radiation exposure is involved.

Considerations    Return to top

Most ultrasound examinations are performed in the manner described. However, certain circumstances require that the ultrasound probe be inserted into the body, rather than simply passing it over the skin. Consult your health care provider to determine the specifics of your test.

Update Date: 10/24/2006

Updated by: Stuart Bentley-Hibbert, M.D., Ph.D., Department of Radiology, Weill Cornell Medical Center, New York, NY. Review provided by VeriMed Healthcare Network.

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