Abstract: A steering mechanism for an ultrasonic transducer assembly includes a housing having a longitudinal axis that extends generally parallel to the proximal end of a catheter. An annular steering ring is mounted to the housing for rotation about the longitudinal axis, and a steering hub is mounted for rotation in the housing and coupled to the steering ring such that rotation of the steering ring with respect to the housing causes rotation of the steering hub. A steering line is secured adjacent the steering hub and extends to the distal end of the catheter such that rotation of the steering hub alters the effective length of the steering line to steer the distal end. The steering line is preferably formed of a stranded polymer such as a gel spun polyethylene.

Abstract: An ultrasonic transducer includes an elongated catheter that carries a phased linear array of ultrasonic transducer elements at a distal end. This array is aligned with the azimuthal axis of the array oriented substantially parallel to a longitudinal axis of the catheter near the distal end. Two sets of steering lines are carried by the catheter and coupled to the catheter near the distal end. The first set of steering lines is effective to steer the distal end in a first plane, and the second set of steering lines is effective to steer the distal end in a second plane, transverse to the first plane.

Abstract: A phased array transducer for an ultrasonic imaging system includes a flexible support element which supports an array of piezoelectric transducer elements. Shape transducers such as strain gauges or capacitive transducers are coupled to the support element to generate a signal indicative of the instantaneously prevailing curvature of the array. A user-controlled actuator is coupled to the support element to flex the support element between at least first and second configurations, wherein the support element has separate curvatures along the axis of the transducer in each of the first and second configurations. In some applications the transducer elements are positioned for separate scan formats in the first and second configurations. The support element can be provided with first and second alternating regions which differ in flexibility, in order to concentrate flexing of the support element in the second regions.