_____________ occurs when the ultrasound beam hits gas or ai…
_____________ occurs when the ultrasound beam hits gas or air. Because of the large drop in acoustic impedance (at the soft tissue/air interface), the entire ultrasound beam is reflected back to the transducer, a portion of which bounces off the transducer and reenters the patient’s body. This occurs repeatedly and appears on the screen as a set of bright parallel lines that are the same distance from each other.