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Ultrasound Imaging

What is ultrasound imaging?

Ultrasound imaging, also known as sonography, is the measure of echoes throughout the body in the form of sound waves. Physicians use ultrasound to determine how far along a woman is in her pregnancy. These sound waves determine the size, shape, and position of the developing baby. Physicians also may use ultrasound imaging to detect tumors or other abnormalities in organs or tissues.  Unlike conventional x-rays, ultrasound does not need to use radiation. Ultrasound is generally safe for a developing baby and mother. A technologist applies a gel before placing and moving the transducer over the skin.

What are the benefits of ultrasound?

Ultrasound is a painless, non-invasive procedure, so there are no needles. Also, ultrasound imaging does not require the use of any ionizing radiation. Ultrasound is a safe, accurate way for physicians to see the progress of a pregnant woman’s developing baby. Physicians also look to ultrasound, a form of real-time imaging, to guide minimally invasive procedures, and to show movement and any abnormalities inside the body.

What happens during an ultrasound?

Ultrasound imaging uses high-frequency sound waves to produce images of your body’s organs, or to check the blood flow through your veins and arteries. Ultrasound scanners consist of a computer, a video display screen, and a transducer. The transducer, similar to a microphone, is attached to the scanner. During the exam, a gel is placed on the skin over the part of your body to be imaged.  The physician moves the transducer to different positions to view parts of the body at different angles. The ultrasound image is immediately visible on a nearby video display screen that looks much like a computer or television monitor. The image is created based on the amplitude (strength), frequency, and time it takes for the sound signal to return from the patient to the transducer and the type of body structure the sound travels through. An ultrasound exam usually takes about 45 to 60 minutes.

Preparing for the test:

  • You should wear comfortable, loose-fitting clothing for your ultrasound exam (You may be asked to wear a gown during the procedure).
  • For some exams, you may be asked not to eat or drink for as many as 12 hours before your appointment.
  • For some exams, you may be asked to drink up to six glasses of water two hours prior to your exam and avoid urinating so that your bladder is full when the scan begins.
  • For gallbladder or abdomen ultrasounds, you should have nothing to eat or drink six hours before the exam.
  • Do not chew gum or smoke for 6 hours before the exam.

What happens after the ultrasound?

Your ultrasound scans are interpreted by our board-certified radiologists, perinatologists, cardiologists, and a team of imaging specialists and delivered to your physician via our state-of-the-art computer system. If your images are ever needed, they can be accessed by any UPMC hospital or facility at any time of the day or night.

If you have any questions about preparing for your ultrasound exam, please call 1-800-533-UPMC (8762).


Additional Information

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Supplemental content provided by A.D.A.M. Health Solutions. All rights reserved.

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