title: The effects of tissue velocity changes on acoustical interfaces.
abstract: Three case reports illustrate the changes in a distal acoustic interface after transmission of an ultrasonic beam through a tissue containing two different tissue velocities. The "break" created in the distal interface should be recognized and should not be interpreted as representing a pathologic change.
mesh_terms: D000368:Aged; D055592:Biophysical Phenomena; D001703:Biophysics; D003560:Cysts / Q000175:diagnosis; D005260:Female; D006801:Humans; D008067:Lipoma / Q000175:diagnosis; D008099:Liver; D008107:Liver Diseases / Q000175:diagnosis; D008113:Liver Neoplasms / Q000175:diagnosis; D008297:Male; D014463:Ultrasonography