A vibrational method and apparatus for accelerating and increase in efficiency of passage of stones from the ureter comprises introducing into the ureter (U) of a catheter (10) with a vibrating head (12) which imparts radial oscillations to the walls of the ureter at a distance of 0 to 30 mm from the areas where the stone (S) is lodged. Catheter (10) is a flexible tube which has a head (12) which is expandable radially and axially by means of an oscillating element (24) driven from a reciprocating vibrational drive (26). Drive (26) has a tapering end (32) which, during its reciprocations, causes expansions and constrictions of the resilient head, due to its interaction with inner projections (18) and (20). The apparatus is universal in its application and can be used without any changes for pushing the stone, located in the upper part of the ureter, back to the kidney, where the stone can be more readily disintegrated by means of subsequent extracorporeal shock wave lithotripsy. By replacing some parts, the apparatus can be converted into an ultrasonic device for accelerating passage of stones or into an ultrasonic device for destruction of stones in the ureter.
The device comprises a shock wave generator (1, 2, 3) of the ballistic type comprising a projectile (1) provided to execute a to and fro movement within a guide tube, under the control of pneumatic means (13, 14, 5) disposed at one end of this guide tube. A waveguide (4, 19) exhibits an entrance interface (9) situated at the other end of the guide tube (2) and provided to be struck periodically by the projectile and thus to generate, by ballistic effect, ultrasonic shock waves. This waveguide per se is formed by a metal rod, one end of which forms the abovementioned entrance interface and can oscillate longitudinally within a guide (12), while its other end is provided to act by impact on the object (21) to be destroyed or to be processed.
An instrument for extracting stones from the urinary tract of a patient comprising a urological catheter (12) and a stone-extracting basket (26) formed from resilient wires and slidingly inserted into catheter (12). The instrument has a drive unit (18) which is connected to the basket via a rod (22). Drive unit (18) transmits to the rod rotation and axial vibrations, which in turn are transmitted to the basket. When rod (22) rotates, curved portion (21) generates radial vibrations which are transmitted to the basket. In order to prevent basket (26) from rotating, but to transmit to it only axial and radial vibrations, rod (24) is connected to basket (26) through a spherical joint (42). On its front end the basket has a filiform (38) which facilitates insertion of the instrument into the urinary tract. In use, after insertion of the catheter to a position in which the basket is aligned with the location of the stone, the basket is released from the catheter and expands. The urologist maneuvers the basket so that the stone is caught inside the basket, and then the basket is pulled back into the catheter to prevent the stone from falling out of the basket. To facilitate extraction, the drive unit is then energized, imparting axial and radial vibrations to the basket, which under these conditions is gradually withdrawn from the patient's body together with the stone caught into the basket.
A horn connectable to an energy source to amplify ultrasound displacement is connected to a transmitter formed of material having relatively high mechanical Q for transmitting ultrasonic energy therethrough at a frequency f, the transmitter having a horn-shaped configuration of length that is a multiple of a half-wavelength .lambda./2, and preferably this horn-shaped configuration is comprised of multiple horn segments, each of a length substantially equal to a multiple of .lambda./2, where .lambda.=c/f (c is the speed of sound in the high Q material). The transmitter has a proximal end of cross-sectional diameter D.sub.1 connected to the horn and a distal end of cross-sectional diameter D.sub.2, where D.sub.1 >D.sub.2. Ultrasonic energy transmitted through the transmitter drives a tip which is coupled to the transmitter by means of a flexible connector.
An ultrasonic cutting tip assembly for an ultrasonic surgical cutting instrument having an ultrasonic transducer. The assembly includes a transition horn which is operatively couplable to the transducer, an elongated ultrasonic vibration-transmitting tube which is separable from the horn, and a threaded retaining nut. The threaded portion of the nut threadably engages the threaded portion of the transition horn to hold the proximal end of the tube and the horn together so that ultrasonic vibrations can thereby be efficiently transmitted from the transducer to the distal end of the tube, and then to the surgical site. The nut threaded portion can be formed either on the outside or the inside of the nut, and when on the outside in one embodiment, the nut and tube can be formed as an integral member to be threaded into the distal end of the horn. The elimination of all exposed tip nut surface angles greater than forty-five degrees increases the hydrodynamic performance of the assembly.
A method for treating obstructions of tubular anatomical passageways of the urinary tract, including the urethra and fallopian tubes, provides inserting an ultrasonic catheter device into an anatomical passageway, passing ultrasound to the distal end of the catheter and infusing liquid infusate to the distal end of the catheter to expel it through lateral fluid outflow apertures at a rate which will cause fluidic dilation of the anatomical passageway.
