What is General Ultrasound Imaging?

Ultrasound is safe and painless, and produces pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or sonography, involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin.

High-frequency sound waves are transmitted from the probe through the gel into the body. The transducer collects the sounds that bounce back and a computer then uses those sound waves to create an image.

Ultrasound examinations do not use ionizing radiation (as used in x-rays), thus there is no radiation exposure to the patient.

General Ultrasound

Because ultrasound images are captured in real-time, they can show the structure and movement of the body’s internal organs, as well as blood flowing through blood vessels.

Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions.

Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats the sound wave data into 3-D images.

A Doppler ultrasound study may be part of an ultrasound examination.

Doppler ultrasound, also called color Doppler ultrasonography, is a special ultrasound technique that allows the physician to see and evaluate blood flow through arteries and veins in the abdomen, arms, legs, neck and/or brain (in infants and children) or within various body organs such as the liver or kidneys.

• Color Doppler uses a computer to convert Doppler measurements into an array of colors to show the speed and direction of blood flow through a blood vessel.

• Power Doppler is a newer technique that is more sensitive than color Doppler and capable of providing greater detail of blood flow, especially when blood flow is little or minimal. Power Doppler, however, does not help the radiologist determine the direction of blood flow, which may be important in some situations.

• Spectral Doppler displays blood flow measurements graphically, in terms of the distance traveled per unit of time, rather than as a color picture. It can also convert blood flow information into a distinctive sound that can be heard with every heartbeat.

What are some common uses of the procedure?

Ultrasound examinations can help to diagnose a variety of conditions and to assess organ damage following illness.

Ultrasound is used to help physicians evaluate symptoms such as:

• pain

• swelling

• infection

Ultrasound is a useful way of examining many of the body’s internal organs, including but not limited to the:

• heart and blood vessels, including the abdominal aorta and its major branches

• liver

• gallbladder

• spleen

• pancreas

• kidneys

• bladder

• uterus, ovaries, and unborn child (fetus) in pregnant patients

• eyes

• thyroid and parathyroid glands

• scrotum (testicles)

• brain in infants

• hips in infants

• spine in infants

Ultrasound is also used to:

• guide procedures such as needle biopsies, in which needles are used to sample cells from an abnormal area for laboratory testing.

• image the breasts and guide biopsy of breast cancer (see the Ultrasound-Guided Breast Biopsy page.

• diagnose a variety of heart conditions, including valve problems and congestive heart failure, and to assess damage after a heart attack. Ultrasound of the heart is commonly called an “echocardiogram” or “echo” for short.

Doppler ultrasound images can help the physician to see and evaluate:

• blockages to blood flow (such as clots)

• narrowing of vessels

• tumors and congenital vascular malformations

• reduced or absent blood flow to various organs

• greater than normal blood flow to different areas, which is sometimes seen in infections

With knowledge about the speed and volume of blood flow gained from a Doppler ultrasound image, the physician can often determine whether a patient is a good candidate for a procedure like angioplasty.