title: Concentric beam Doppler: should we be going in circles?
authors.forename: A C
authors.initials: AC
authors.lastname: Perrino
authors.forename: P G
authors.initials: PG
authors.lastname: Barash
mesh_terms: D001011:Aorta / Q000502:physiology; D001783:Blood Flow Velocity; D002302:Cardiac Output; D006801:Humans; D014463:Ultrasonography