Abstract: A catheter is provided that has both an ultrasonic transducer array (2) and a inflatable balloon (12) mounted at or near its distal end. A sheath catheter having a transducer array and associated multiplexer (4) arrangement located substantially coaxially within it. Furthermore, a guidewire (8) catheter having an ultrasonic transducer array mounted on it distal end.

Abstract: An ultrasonic color Doppler imaging system capable of discriminating an artery and a vein discriminates types of blood vessels such as the artery and the vein, and discriminatively displays the discriminated result on a display. The blood vessel types of the artery and the vein are determined using blood stream information according to a temporal change of a blood stream velocity pattern, and a different color is displayed according to the determined blood vessel type. Also, the brighter or darker color is displayed according to the blood stream velocity flowing in the blood vessel, to thereby provide accurate blood stream information.

Abstract: The present invention comprises: a search unit; a hollow guide for stabbing a subject; a manipulating device for protruding the search unit out of the tip of the guide and for moving the search unit along a predetermined orbit; device for transmitting/receiving the ultrasound during the movement by the manipulating means along the orbit; and device for producing an image based on the received echo signal by means of an aperture synthesis technique.