A dual frequency ultrasonic and sonic actuator with constrained impact mass is presented. According to one aspect, displacement of the impact mass is constrained by cavity to which ultrasonic stress from the tip of a horn is applied. According to another aspect, the displacement of the impact mass is constrained by a spring attached to the tip of the horn. According to another aspect, the displacement of the impact mass is constrained by a flexure. The constrained impact mass converts the ultrasonic stress to lower frequency sonic stress that is coupled to a transmitting element for transmission through a surface. According to one aspect, the transmitting element is a longitudinal probe. According to another aspect, the transmitting element is a drill bit used to penetrate though the surface. According to another aspect, the transmitting element is a thumper used to transmit elastic waves though the surface.

An elongate endovascular element for crossing through an obstruction in a blood vessel comprises: a proximal section; a distal tip section of smaller diameter than the proximal section; and a distally-tapering intermediate section extending between the proximal and distal tip sections; wherein the tapered intermediate section has a length that is substantially λ/2 or a multiple of λ/2, where λ is a wavelength of a driving frequency that will produce longitudinal resonance in the element.

A medical device may include an elongated body, a balloon positioned at a distal portion of the elongated body, and one or more pressure-wave emitters positioned along a central longitudinal axis of the elongated body within the balloon. The one or more pressure-wave emitters may be configured to propagate pressure waves radially outward through the fluid to fragment a calcified lesion at the target treatment site. The at least one of the one or more pressure-wave emitters may include an electronic emitter comprising a first electrode and a second electrode. The first electrode and the second electrode may be arranged to define a spark gap between the first electrode and the second electrode, and the second electrode may comprise a portion of a hypotube.

An endovascular apparatus for crossing through an obstruction in a blood vessel comprises an elongate endovascular element such as a wire. The element has a proximal section, a distal tip section of smaller diameter than the proximal section; and a distally-tapering intermediate section extending between the proximal and distal tip sections. The apparatus comprises an ultrasonic transducer, mechanically coupled to the proximal section of the element for ultrasonically activating the element, hence exciting the distal tip section to facilitate crossing through the obstruction. A catheter surrounds the element, leaving at least part of the distal tip section of the element protruding distally beyond a distal end of the catheter.

An endovascular apparatus for crossing through an obstruction in a blood vessel comprises: an elongate endovascular element such as a wire; an ultrasonic transducer, mechanically coupled to the endovascular element for ultrasonically exciting a distal tip portion thereof to facilitate the crossing through the obstruction, and one or more damping features, mechanically coupled to the endovascular element to attenuate lateral displacement of the endovascular element at positions away from the distal tip portion.

A PZT transducer-horn integrated ultrasonic driving structure consists of a nut, a bolt, a left PZT circular stack, a flange, a right PZT truncated stack and a horn. The horn, the right PZT truncated stack, the flange and the left PZT circular stack are arranged in sequence and connected via the bolt and then fastened via the nut; the right PZT transducer is a truncated cone-shaped stack formed by PZT circular plates; and the right PZT transducer and the horn are integrated to form the ultrasonic driving structure. Considering the dimension of PZT on two sides of the flange and the horn meet the requirements for ultrasonic vibration node and antinode, the dimension of round contour of the circular PZT stack and flange is reduced to increase the thickness of the truncated PZT stack and flange. With the integrated structure, the effect of reducing the contour dimension of the ultrasonic driving surgical device can be obtained, and the outer diameter is reduced to the range of 8-10 mm as compared with the range of 12-15 mm in the prior art, thereby further meeting the application requirements.

A medical instrument includes a tubular cutter extending along an axis and having a windowed outer sleeve and a moveable inner cutting sleeve. An ultrasound transducer is operatively coupled to the inner cutting sleeve in order to induce motion in the inner cutting sleeve to enhance cutting or resection of tissue by the inner cutting sleeve as it is reciprocated or otherwise moved past the cutting window. The instrument typically will include a motor drive configured to reciprocate and/or rotate the inner cutting sleeve relative to the windowed outer sleeve, usually at a reciprocation rate between 1 and 10 Hz.

An elongate endovascular element for crossing through an obstruction in a blood vessel comprises: a proximal section; a distal tip section of smaller diameter than the proximal section; and a distally-tapering intermediate section extending between the proximal and distal tip sections; wherein the tapered intermediate section has a length that is substantially λ/2 or a multiple of λ/2 , where λ is a wavelength of a driving frequency that will produce longitudinal resonance in the element.

A method of fabricating an ultrasonic medical device is presented. The method includes machining a surgical tool from a flat metal stock, contacting a face of a first transducer with a first face of the surgical tool, and contacting a face of a second transducer with an opposing face of the surgical tool opposite the first transducer. The first and second transducers are configured to operate in a D31 mode with respect to the longitudinal portion of the surgical tool. Upon activation, the first transducer and the second transducer are configured to induce a standing wave in the surgical tool and the induced standing wave comprises a node at a node location in the surgical tool and an antinode at an antinode location in the surgical tool.

A medical device may include an elongated body, a balloon positioned at a distal portion of the elongated body, and one or more pressure-wave emitters positioned along a central longitudinal axis of the elongated body within the balloon. The one or more pressure-wave emitters may be configured to propagate pressure waves radially outward through the fluid to fragment a calcified lesion at the target treatment site. The at least one of the one or more pressure-wave emitters may include an electronic emitter comprising a first electrode and a second electrode. The first electrode and the second electrode may be arranged to define a spark gap between the first electrode and the second electrode, and the second electrode may comprise a portion of a hypotube.