Diagnostic medical sonographers use special imaging equipment that directs sound waves into a patient's body (in a procedure commonly known as ultrasound, sonogram, or echocardiogram) to assess and diagnose various medical conditions.

Diagnostic ultrasound uses high-frequency sound waves to produce images of the inside of the body. The sonographer presses an instrument called an ultrasound transducer to the parts of the patient's body that are being examined. The transducer emits pulses of sound that bounce back, causing echoes. The echoes are then sent to the ultrasound machine, which processes them and displays them as images.