Diagnostic ultrasound, sometimes called sonography, is a procedure that uses sound waves higher than the human ear can detect to examine structures and tissues within the body. A small device called a transducer is used to send sound waves into the body, which are reflected off of internal structures. The returning sound waves (echoes) are then sent back to the same transducer and the attached equipment electronically changes the echoes into a picture of your internal structures.
A warmed gel will be applied to the skin surface to provide better contact between the transducer and the skin. The gel is easily removed, but the patient should wear easily washable clothing. Ultrasound provides a noninvasive, safe and painless means of observing soft tissue anatomy.
Ultrasound cannot be used to examine bones because bone weakens sound waves. In addition, ultrasound cannot obtain images through bowel gas. There are no known harmful effects associated with the medical use of sonography.