Ultrasound Procedures and Exams

Abdominal
Neck/Thyroid
Pelvic
Obstetrical
Venous/Arterial
Musculosketal

Abdominal ultrasound is used to examine internal organs such as the gallbladder, liver, spleen, kidneys, and bladder. Common reasons for an abdominal ultrasound include:

1. To look for causes of abdominal pain, particularly from your gallbladder or bile ducts.
2. Evaluate enlarged organs that your physician may have felt at a physical examination.
3. To biopsy a mass with a needle, or to drain an infection.

Abdominal Doppler ultrasound is focused specifically on blood vessels. Doppler ultrasound is used to evaluate:

1. Blood clots.
2. Atherosclerosis and narrowed blood vessels.
3. Congenital blood vessel abnormalities.

HOW TO PREPARE FOR YOUR ABDOMINAL ULTRASOUND

Wear comfortable, loose fitting clothing. In general, do not eat or drink anything for at least 6 hours before your study. Please do not bring young children with you as they get bored and may disrupt the exam.

WHAT WILL HAPPEN DURING YOUR EXAM

Ultrasound imaging is painless, fast and easy. You will lie on your back, or side, on the examining table. The sonographer will spread gel on your skin and place the transducer firmly against your body. They will move the transducer to obtain the appropriate images. The examination usually takes 30 minutes.

THE ULTRASOUND MACHINE

The Ultrasound machine has a transducer, which is a small hand-held device which looks like a microphone. The sonographer will put a clear, water-soluble, lubricating gel on your skin and firmly press the transducer against the skin.

The ultrasound image is then seen on a computer screen attached to the machine. The radiologist or sonographer watches this screen during this examination. During the examination, they will "freeze" the images on the screen and save images from it, which will be evaluated by the radiologist.

Ultrasound is based on the same principles as sonar used by ships, bats or fishermen with fish detectors. As the sound waves go through the body, the waves bounce back, or "echo", back to the transducer. A very fast computer in the ultrasound machine interprets how far away the tissue is that caused the echo, its size, shape and consistency (such as fluid or solid). It then turns this information into the pictures you see on the monitor.

Most of the images are of varying shades of gray. These are "2-D" images that show anatomy. Images also can be obtained with Doppler, which detects movement in the tissues, particularly in blood. These Doppler images can be shown on the computer either as color Doppler pictures or as duplex Doppler pictures. Duplex Doppler shows us white waves, and is usually associated with listening to the waves at the same time, which often gives a rhythmic whooshing sound.

For more information on abdominal ultrasound, check out: www.radiologyinfo.org/content/ultrasound-abdomen.htm (a good general site on abdominal US), and http://www.nlm.nih.gov/medlineplus/ency/article/003777.htm (a similar site, by the National Institutes of Health, with general pictures)