Erhard Schmidt

Shockwave source having a centrally disposed ultrasound locating system

A shockwave source of the type wherein a shockwave is generated by rapid electromagnetic repulsion of a membrane by a rapidly energized coil has a central opening extending through the membrane and the coil. An ultrasound head of an ultrasound transmission and reception system is received in the opening. The ultrasound head is disposed in a mount which is rotatable around its longitudinal axis by a rotary drive. In one embodiment of the shockwave source, the shockwave source also has a focusing device disposed in front of the membrane, and in this embodiment the focusing device also has a central opening in which the ultrasound head is received. The ultrasound head has a distal end in contact with a liquid coupling agent for promoting transmission to, and reception from, a patient to which the shockwave source is coupled. The shockwave source is particularly suited for lithotripsy treatment of gallstones.

Lithotripter with locating system integrated therewith and method for its use

A lithotripter for disintegrating a calculus in the body of a patient has a shock wave source which emits shock wave pulses which are focussed to the calculus by an acoustic lens. As seen in the propagation direction of the shock wave pulses, a semi-transmissive acoustic mirror is disposed in front of the acoustic lens at a fixed angle. An ultrasound transducer, which is part of an ultrasound locating system, such as an ultrasound sector scanner, is disposed laterally with respect to the acoustic mirror, so that ultrasound waves are transmitted by the transducer to the calculus, and the reflected waves are transmitted from the calculus to the transducer, reflected by the acoustic mirror. Shock wave pulses from the shock wave source are only minimally impeded by the mirror, so that the therapy is substantially uninfluenced by the presence of the mirror. The ultrasound signals are used to identify the position of the calculus in the patient, so that the position can be continuously observed, even during the time in which the shock pulses are acting on the calculus. The approach path of the shock wave pulse to the calculus can also be ultrasonically monitored.

Ultrasound transducer arrangement having an acoustic matching layer

In an ultrasound transducer arrangement having an electroacoustic transducer part, at least one acoustic matching layer is allocated to the transducer part. The acoustic matching layer is composed of an electrically conductive skeleton having interspaces connected to one another. The skeleton is constructed of particles connected to one another. The size of the particles is smaller than the wavelength of an acoustic wave in a matching layer, as a result of which no significant scattering of the wave occurs in the matching layer. The interspaces are filled with a curable casting compound.