An ultrasound scan, sometimes called a sonogram, is a procedure that uses high-frequency sound waves to create an image of part of the inside of the body. A small device called an ultrasound probe is used, which gives off high-frequency sound waves. When these sound waves bounce off different parts of the body, they create "echoes" that are picked up by the probe and turned into a moving image. This image is displayed on a monitor while the scan is carried out. The scan can take 30-45 minutes to complete. Ultrasounds are commonly used to monitor pregnancy and can diagnose issues in the breast, eyes, thyroid, skin, and muscles.