Ultrasound imaging, also called Ultrasound Scanning or Sonography, involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. Ultrasound exams do not use ionizing (X-ray) radiation. 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.

In an Ultrasound examination, a transducer both emits sound waves and records the waves as they echo. When the transducer is pressed against the skin, it directs a stream of inaudible, high-frequency sound waves into the body. As the sound waves bounce off of internal organs, fluids and tissues, the sensitive microphone in the transducer records tiny changes in the sound’s pitch and direction. These signature waves are instantly measured and displayed by a computer, which in turn creates a real-time picture on the monitor. These live images are usually recorded on videotape, and one or more frames of the moving pictures are typically captured as still images.

A Doppler Ultrasound study may be part of an Ultrasound examination. This special technique measures the direction and speed of blood cells as they move through vessels, including the body’s major arteries and veins in the abdomen, arms, legs and neck. The movement of blood cells causes a change in pitch of the reflected sound waves (known as the Doppler effect). A computer collects and processes the sounds and creates graphs or pictures that represent the flow of blood through the blood vessels.

Procedure

Most ultrasound examinations are painless, fast and easy. Depending on your procedure, you may be asked to change from your street clothes into a gown. While lying on a cushioned examination stretcher, the UMI sonographer will rub a warm gel on your skin around the area to be examined. 

About the Gel

• All Ultrasound exams at UMI use a warmed gel for patient comfort.
• The gel acts as a coupling agent, so that the sound waves emitted from the transducer can be efficiently transmitted and received to and from the body.
• Once the imaging is complete, the gel will be wiped off your skin. The water-soluble gel does not stain fabrics or skin. Also, because it is hypoallergenic, its use carries no risk of allergic reaction.

After the gel is applied, the sonographer will press the transducer firmly against your body, moving it back and forth over the area of interest until the desired images are captured. There may be varying degrees of discomfort from pressure as the transducer is pressed against the area being examined. You may be asked to hold your breath for short periods of time throughout the exam.

Ultrasound exams in which the transducer is attached to a probe and inserted into an opening of the body may produce minimal discomfort.

If a Doppler Ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured.

A typical Ultrasound exam takes approximately 40 minutes. After an Ultrasound exam, you should be able to resume your normal activities. 

General preparation tips

• Please arrive 15 minutes prior to the exam time to complete a registration form, billing information, and a brief medical history questionnaire.
• The following Ultrasound exam modalities require no special pre-exam preparation: Arterial, Musculoskeletal, Scrotal, Trans-vaginal, Thyroid and Venous.
• Other exam types that require preparation include:
• Pelvic: Please drink 32 oz. (one quart, or four eight-ounce glasses) of water one hour prior to the time of the exam. This will ensure a full bladder, which facilitates a proper diagnostic setting. (If your bladder becomes painfully full, feel free to urinate just enough to be comfortable while still ensuring a full bladder for the exam.)
• Abdomen: (kidneys, gallbladder, liver, pancreas, aorta, and spleen): It is important that you take nothing by mouth (i.e., no food or water) after midnight of the evening preceding a morning abdominal Ultrasound. If the exam is scheduled for an afternoon, please be sure to fast for at least 4 hours prior to the exam. (Note: If the exam is called for under urgent conditions and the fasting guidelines cannot be followed, please notify your UMI radiologist before the exam gets underway.)
• Your entire stay for the exam is estimated at 1 hour, including advance arrival time.

For more detailed information on many radiology procedures, please visit this informational site.