Ultrasound is a medical imaging technique that uses a physical mechanic similar to a submarine’s sonar or dolphin echolocation. The device, called a transducer, sends out high frequency sound waves and then “listens” to the response to create an image based on the sound reflected back at the machine.

This visualization allows the doctor to determine the location of abnormal growths, if there is leakage or rupture in blood vessels, or simply the exact shape and size of the targeted organ to be operated on. Additionally, all image recording happens in “real” time as soon as the machine is turned on and placed on the body. There is no wait for any sort of picture development needed for x-rays and other imaging procedures.

How It Works

The ultrasound procedure begins with the patient lying down on the examination table as a water-based gel is applied to the area on their body that will be observed. This gel allows consistent contact between the body and the transducer, free of any air pockets that could get in the way. The transducer is kept firmly against the skin and is moved back and forth across the area to allow for the most detailed observation possible. The whole procedure usually takes 30 minutes.

There is no discomfort associated with this procedure, although if the part of your body being observed has already been tender there may be some slight pressure against it. If a Doppler type ultrasound is used, you may actually hear the pulses of the device. There is no clinical risk inherent in ultrasonography as it uses no invasive methods, no ionizing radiation, and does not cause any health problems.

How to Prepare

You should come prepared to your ultrasound exam wearing loose-fitting clothing and no jewelry. Please keep in mind that your clothing may need to be removed, depending on what body part is being imaged. Also, it is important to inform your doctor if you have taken a barium enema or any other upper gastrointestinal tract tests within the past few days as they can severely distort the ultrasound image.

If any part of your gastrointestinal tract, aorta, liver or pancreas must be observed, then you will be advised to stop eating for the twelve hours prior to the exam. If your kidneys are the target organ, you may need to drink several glasses of water one hour before the exam, in addition to the aforementioned eating requirements. Your doctor will inform you of any special preparations needed for your specific exam.