An ultrasound transducer includes a plurality of piezoelectric elements that are layered in the thickness direction and that generate a longitudinal vibration in the thickness direction. The plurality of piezoelectric elements are arranged so that the thicknesses thereof are sequentially larger from the antinode side of the longitudinal vibration towards the node side of the longitudinal vibration.

An ultrasonic transducer assembly of an ultrasonic surgical instrument includes a piezoelectric stack, an ultrasonic horn secured to and extending distally from the piezoelectric stack, and a casing. The ultrasonic horn includes a body and a nose extending distally from the body. The casing is disposed about the piezoelectric stack and the body of the ultrasonic horn. The casing defines a distal opening through which the nose of the ultrasonic horn extends. The casing is hermetically sealed to the ultrasonic horn about the distal opening to define a hermetically sealed interior enclosing the piezoelectric stack and the body of the ultrasonic horn therein.

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.

A system for delivering ultrasound energy to an internal anatomical target includes an ultrasound transducer having multiple transducer elements collectively operable as a phased array; multiple driver circuits, each being connected to at least one of the transducer elements; multiple phase circuits; a switch matrix selectably coupling the driver circuits to the phase circuits; and a controller configured for (i) receiving as input a target average intensity level and/or an energy level energy to be applied to the target and/or a temperature level in target, (ii) identifying multiple sets of the transducer elements, each of the sets corresponding to multiple transducer elements for shaping and/or focusing, as a phased array, ultrasound energy at the target across tissue intervening between the target and the ultrasound transducer, and (iii) sequentially operating the transducer-element sets to apply and maintain the target average energy level at the target. In various embodiments, the controller operates each of the transducer element sets in accordance with a pulse-width modulation pattern having a duty cycle selected to achieve the target average intensity level, energy level, and/or temperature level at the target in accordance with a time constant of the target tissue.

A method for generating a mechanical wave, including generating a high amplitude mechanical pulse; coupling the mechanical pulse in a proximal end of a transmission member; propagating the mechanical pulse into the transmission member from the proximal end and a distal end thereof; and transmitting the mechanical pulse at the distal end.

A surgical instrument includes a transducer assembly with a housing having a conduit section and a base portion. A fluid passageway is defined through the conduit and base portion, an ultrasonic transducer including a plurality of piezoelectric elements and a plurality of electrodes are arranged in a stack configuration, where an electrode is located between each pair of piezoelectric elements. A first borehole is defined through the ultrasonic transducer and an end mass having a second borehole defined therethrough. A surface of the end mass is positioned adjacent a first end of the ultrasonic transducer, the end mass is configured to engage with the housing, and the conduit section of the housing is configured to pass through the second borehole of the end mass. The end mass is configured to compress the ultrasonic transducer against a surface of the housing when the end mass is engaged with the housing.

A method for generating a mechanical wave, including generating a high amplitude mechanical pulse; coupling the mechanical pulse in a proximal end of a transmission member; propagating the mechanical pulse into the transmission member from the proximal end and a distal end thereof; and transmitting the mechanical pulse at the distal end.

There is provided in accordance with an exemplary embodiment of the invention a method of treating a subject suffering from a nerve related disorder, the method comprising causing a damage region to one or both of a lumen wall or nearby surrounding tissues, the damage region encompassing a volume having dimensions of less than about 6.8 mm in a substantially radial direction, less than about 5.8 mm in a direction substantially tangential to the lumen, less than about 10 mm in a substantially axial direction, the damage region being located no closer than about 0.2 mm from an inner wall of the lumen, the damage region comprises of greater than about 60% of collagen denatured tissue.

A surgical instrument includes a transducer assembly with a housing having a conduit section and a base portion. A fluid passageway is defined through the conduit and base portion, an ultrasonic transducer including a plurality of piezoelectric elements and a plurality of electrodes are arranged in a stack configuration, where an electrode is located between each pair of piezoelectric elements. A first borehole is defined through the ultrasonic transducer and an end mass having a second borehole defined therethrough. A surface of the end mass is positioned adjacent a first end of the ultrasonic transducer, the end mass is configured to engage with the housing, and the conduit section of the housing is configured to pass through the second borehole of the end mass. The end mass is configured to compress the ultrasonic transducer against a surface of the housing when the end mass is engaged with the housing.

A method of treating a calculi mass can include using an ultrasonic probe to produce acoustic energy and fragment the mass. The method can include varying the frequency at which fragmentation occurs to treat the mass with a resonant frequency. The ultrasonic probe can have a distal tip for contact with the mass, where the tip has a morphology for concentrating stress on the mass. The ultrasonic probe can have two or more ultrasonic horns to allow for higher voltage and power levels.