Abstract: A device for producing high pressure ultrasound pulses. The device includes an ultrasound source having a piezoelectric transducer provided with electrodes and presenting polarization in a given direction (f1). An electrical voltage is applied to the electrodes to emit an ultrasound wave and to apply an electric field in a direction (f2) opposite to the polarization direction (f1) in order to compress the ultrasound transducer. A transient electric field having the same direction (f3) as the polarization direction (f1) is then applied so as to cause a compression ultrasound wave to be emitted in the coupling medium.

Abstract: A device for producing high pressure ultrasound pulses. The device includes an ultrasound source having a piezoelectric transducer provided with electrodes and presenting polarization in a given direction (f1). An electrical voltage is applied to the electrodes to emit an ultrasound wave and to apply an electric field in a direction (f2) opposite to the polarization direction (f1) in order to compress the ultrasound transducer. A transient electric field having the same direction (f3) as the polarization direction (f1) is then applied so as to cause a compression ultrasound wave to be emitted in the coupling medium.

Abstract: A method for treating myomas or tumors having a pedicle includes the steps of locating the pedicle of a myoma or a tumor using Doppler echography and delivering focused ultrasound to the pedicle.

Abstract: An ultrasound applicator for heating, via an internal path, an ultrasound absorbent medium, includes an application head having a longitudinal axis and including at least one ultrasonic transducer having a planar emission face and an opposite face, a leakproof membrane which overlays and is spaced from the emission face, and which is transparent to ultrasound, and means for preventing propagation of ultrasound from the opposite face; means for remotely connecting the transducer to an electricity generator; and means for providing ultrasound coupling with the membrane. The planar emission face emits ultrasound waves through the membrane and in a direction that is substantially perpendicular to the emission face, such that the waves emitted are substantially planar and do not diverge in the vicinity of the transducer and the application head.

Abstract: The invention relates to the use of Dirac-type autocorrelation function signals for powering multielements ultrasonic transducers used in therapeutic application in order to minimize or eliminate secondary focusing. The Dirac-type autocorrelation function signals may be generated by a pseudo random binary code.

Abstract: A therapeutic endo-rectal probe comprises at least a piezoelectric transducer element mounted in a support member itself connected to a rigid guide means enabling endo-rectal insertion of said probe, the outside shape of said support member preferably being that of a disk having an outline that is for the most part substantially circular or substantially elliptical, thereby facilitating endo-rectal insertion.

Abstract: A method and apparatus for performing therapy using ultrasound. The apparatus uses a treatment device having at least one piezoelectric transducer element to supply ultrasonic waves focussed onto a focal point or region that determines the tissue zone submitted to therapy. The treatment device, which is controlled by a control device, supplies two types of ultrasonic waves, the first one being thermal waves that produce a predominantly thermal effect on the tissue being treated and the second one being cavitation waves that produce a predominantly cavitation effect on the tissue to be treated.

Abstract: An ultrasonic probe for flow rate measurement by the Doppler effect includes at least one wide-beam ultrasound transducer fixed on a support block and at least one narrow-beam ultrasound transducer fixed on a support block and whose beam position is known in relation to the wide beam, and a control and processing unit which processes and measures the characteristics of the signal from the narrow-beam transducer in order to determine the only appropriate direction for pointing the wide-beam transducer to enable an accurate measurement of flow rate to be performed.

Abstract: A therapeutic endo-rectal probe comprises a piezoelectric transducer element mounted in a support member itself connected to a rigid guide means enabling endo-rectal insertion of the probe, the outside shape of the support member preferably being that of a disk having an outline that is for the most part substantially circular or substantially elliptical, thereby facilitating endo-rectal insertion.

Abstract: The invention relates to an apparatus for a real-time tracking and imaging of objects. The apparatus comprises of a real-time image forming device, a device for coupling the image forming device with a wave generator generating waves adapted to effect appropriate treatment of said object directed towards a target focus, wherein the coupling device includes a device for displacing the image forming device relative to said target focus. The invention offers the advantage of great positional freedom for the image forming device, enhanced resolution and safe observation of objects within the body of a mammal, and in particular a human being. The object is in particular selected from a concretion, a bone or a tumor, notably a cancerous tumor.

Abstract: The invention relates to a composite piezoelectric transducer for making an acoustic or an ultrasonic therapeutic apparatus. The transducer may be a single large-size transducer or it may be a multi-transducer device and it advantageously emits ultrasonic waves that are focused on a focal point.

Abstract: The invention relates to a method for manufacturing an acoustic sensor, and also to the sensor. The sensor comprises a piezoelectric sheet (12) mounted on a support (14) and electrically connected to electrodes (16,18) connected by electrical conductors (20,22) to a measurement device, characterized in that the assembly constituted by the sheet (12) and its support (14) is coated with a one-piece polymerizable coating layer (24) which is preferably electrically insulating, such that the portion (24a) of the coating layer (24) overlying the sheet (12) constitutes a protective layer which is rendered non-detachable or essentially non-detachable from the piezoelectric sheet (12). The method for manufacturing this sensor is extremely simple and inexpensive, and the protective layer is non-detachable.

Abstract: The present invention relates to a method and a device for producing an electric discharge between two electrodes. This method characterized in that the resistance to the passage of the electric arc, at least between the electrodes, is considerably reduced so as to bring it to a resistance value near to or slightly higher than the critical resistance, by interposing at least between the electrodes, an electrically conductive electrolyte contained in an essentially closed reservoir surrounding the electrodes. The invention makes it possible to improve the rate of discharge of an electric current produced between the electrodes, by eliminating substantially completely the latency time.

Abstract: The invention relates to a process for manufacturing a device generating shockwaves which are only slightly, if at all, felt be the patients.This shockwave generating device comprises a truncated ellipsoidal reflector (12) which has a ratio (b)/(a) greater than 0.69, and preferably between 0.60 and 0.85 and a connection (14) supplying electric current to the electrodes (6, 8), which connection comprises a capacitor (18) having a capacitance less than or equal to 500 nanofarads.The result is a reduction of the energy density at skin level of the emitted shockwaves which are only slightly, if at all, felt by the patients, thus permitting a treatment without anaesthesia.

Abstract: The invention relates to an apparatus for selective destruction of cells including soft tissues and bones inside a living subject's body.This apparatus is characterized in that it comproses:means for generating gas bubbles in situ within the cells to be selectively destroyed, andimplosion means capable of provoking the implosion in situ of the gas bubbles, thereby destroying the cells to be destroyed which are adjacent the imploded gas bubbles.The invention makes it possible to destroy cells inside a living subject's body by a non-invasive and extracorporeal and also extremely simple and efficient way, further permitting the treatment of metastases.

Abstract: The present invention relates to a method and device for discharging an electric current between two electrodes, comprising considerably reducing the resistance to the passage of electric current at least between the electrodes so as to bring it to a resistance value near to or slightly higher than the critical resistance by interposing a conductive electrolyte between electrodes. This improves the rate of discharge of an electric current produced between the electrodes, by eliminating substantially completely the latency time.

Abstract: The invention relates to a device for providing improved electrical contact between an electrical conductor and an electrode. The device is characterized in that it comprises a fixed position nut-forming contact element made of an electrically conductive material and including an axial bore through which the electrode passes, the electrical conductor terminating at the nut-forming element in the form of a connection tab. The nut-forming element advantageously comprises two half-disks for facilitating assembly and disassembly while providing improved electrical contact during operation.

Abstract: A method and apparatus for coordinating the initial positions in three dimensions of a device (10) for triggering and focusing shots and a locating arm (14). The apparatus includes structure (20) for calibrating the distance (D) between the free end (14a) of the locating arm (14) and the device (10) for triggering and focusing shots, the calibration structure (20) preferably comprising a link member (22). The invention improves the accuracy with which a target is located and, therefore, the effectiveness with which it is destroyed.

Abstract: The invention relates to a device generating ultrasonic waves focused in a ocal point. Said generator device comprises a plurality of transducer elements arranged externally on a support means for focusing into a focal point, such as a circular dome, and is characterized in that the transducer elements are divided into at least two groups of transducer elements, of which the resonance frequency differs in such a way that the principal positive ultrasonic waves produced by each group add up together and the positive and negative secondary ultrasonic waves are at least partly cancelled, thus reducing significantly the negative waves. This device can be advantageously used for extracorporeal lithotripsy.

Abstract: The invention relates to a method and to a device for improving the dische regime of an electric arc produced between two electrodes. The device is characterized in that it includes means an insulating element (32), preferably spherical in shape, for increasing the resistance to the passage of the electric arc (A) between ends of the electrodes (12, 14). By using the invention it is possible to obtain an arc discharge of the critically damped type. The method and the device are preferably used in shock wave generator apparatus for hydraulic lithotripsy.