DE4331020A1 - Ultrasonic medical investigation and treatment appts. with three=dimension display - uses focussing piezoelectric ultrasonic source with two or three dimensional receiving transducer array - Google Patents

Abstract

The ultrasonic source (1) is a spherically shaped piezoelectric device with a central opening (2) producing ultrasonic waves in a sector (RS1 to RS2) with a focus point (F) on the optical axis (A). In the free space bounded by an inner sector (RS2,RS2) an acoustic lens (3) is positioned with a focal point (F) lying in the optical axis of the transducer array (4). The latter consists of a spatial 4 x 4 x 4 ultrasonic sensor matrix whose output signals are acquired by an electronic unit (5) and displayed on a VDU (6). USE/ADVANTAGE - Therapeutic ultrasonic treatment of internal organs using display for location purposes. Simple and time-saving.

Description

The invention relates to an ultrasound imaging device to generate an ultrasound image of an object and a Therapy device for treating a patient's body object located with focused acoustic world len, which as a location device for the object to be treated contains such an ultrasound imaging device.

Conventional ultrasound imaging devices produce in the Re gel a two-dimensional image of an object to be imaged, where it is with the generated image, one sees from the so-called called ultrasonic cameras (US Pat. No. 5,072,722), as a rule is a sectional view of the object, such as in Case of the widespread B-mode ultrasound image (U.S. Patent No. 4,526,168). Three-dimensional ultrasound images can be made in the Usually only be generated with great effort, for example by making one under different areas of the object-detecting number of ultra sound cross-sectional images, from which the data for the production a three-dimensional ultrasound image are extracted (U.S. Patent 5,005,579). Such an approach is cumbersome and time consuming compared to the usual ultrasonic cut Image imaging devices that provide real-time images. In Therapy devices for the treatment of in the body of a pati objects located with focused acoustic waves are therefore almost out of ultrasound tracking devices finally contain ultrasound imaging devices that only deliver sectional images. Still, it would be in the interest a more effective and gentler treatment progress, via additional image information  Lich to be able to dispose of the object to be treated Alignment of the therapy facility and the patient's body would make ducks simpler relative to each other.

The invention has for its object an ultrasound Ab educational institution specifying it on simple, time Economical and therefore economical way allowed, spatial Take ultrasound pictures of an object. The invention is still the task of a therapy facility for the treatment of an ob in the body of a patient jektes with focused acoustic waves whose ul Traschall locating device in the interest of a better Aus Direction of the therapy facility and the patient's body relative to each other compared to conventional therapy facilities provides additional image information.

According to the invention, the ultrasound imaging device part of the task solved by an Ultra sound imaging device for imaging an object, having

• a) a source of acoustic waves, which are pulse-like, in egg generates converging acoustic waves at the focus,
• b) an acoustic imaging lens, the object-side focal point lies in the area of the focus of the acoustic waves,
• c) Ultrasonic sensor means with at least two dimens sional sensor matrix in the area of the image side Focal point of the imaging lens is arranged, which is the spatial distribution of the pressure on the image to be imaged Reflected object, stepped through the imaging lens Corresponding proportions of the pulse-like acoustic waves output electrical output signals,  
• d) imaging electronics, which the output signals of the Ultrasound sensor means are supplied and the reason the output signals were scaled, real, three dimensional image of the object generated, and
• e) display means showing the image, preferably in perspective or two-dimensional.

While in the case of conventional, according to the layplan principle working ultrasound imaging equipment a variety must be emitted by pulsed acoustic waves in order to generate a single slice (the achievable resolution increases with the number of impulsive acoustics emitted waves), is sufficient in the case of the invention due to the Use of an at least two-dimensional sensor matrix un depending on the resolution of the sensor matrix, a single im pulse-like acoustic wave to in relation to the area in which are the pressure sensors of the sensor matrix, which are used for Get the signals necessary for imaging. To this In this way, a considerable gain in speed is achieved. In in fact, when using a two-dimensional Sensor matrix provided the same in each case A three-dimensional ultrasound image in im can be generated essentially at the same time as a conventional one Lich ultrasound cross-section, so that three-dimensional ultra sound images can be generated in real time. Under in real Ultrasound images generated at this time are said to be ultra sound pictures can be understood in such a short time span are generated that the state represented in the image also in the case of moving objects essentially with that at the end the present state of the object Right. The duration of the image creation process can therefore be for me medical purposes do not significantly exceed 200 to 300 ms  and should preferably be in the order of magnitude of approximately 60 ms gene, since then with continuous, immediately successive gender imaging the representation of the object as flicker or is felt smoothly. Imaging can be done in a similar way way (e.g. time window) as with conventional Ultra sound devices. Imaging can also be done by a computation process that results from the radiation optics itself known algorithms are based.

When using a two-dimensional sensor matrix according to a variant of the invention provided that the ultrasonic Sensor means one level in several, preferably regularly arranged pressure sensors divided sensor matrix and means to adjust the distance between the sensor matrix and the Have imaging lens. The adjustment is made step by step wise, preferably with a step size that corresponds to the distance between two adjacent pressure sensors of the two corresponds to the dimensional sensor matrix. It is achieved that the measurement of the spatial distribution of the pressure on spatial regularly arranged measuring points. The adjustment of the Distance between the sensor matrix and the imaging lens can both by adjusting the sensor matrix relative to the Imaging lens as well as by adjusting the imaging lens relative to the sensor matrix. The adjustment is made preferably in the direction of the acoustic axis of the Imaging lens.

While in the case of using a two-dimensional sensor matrix for creating a three-dimensional image of the object tes needs a number of pulse-like acoustic waves which is equal to the number of steps by which the Ab stood between the sensor matrix and the imaging lens must be provided is sufficient in the case of a preferred embodiment Form of the invention for creating the three-dimensional  Image of the object a single pulse-like acoustic wave. This embodiment of the invention provides that the Ultra sound sensor means designed as a three-dimensional sensor matrix leads, which is a preferably regular spatial An order of pressure sensors contains. Capturing the spatial Distribution of the pressure can therefore be based on the reflected An parts of a single pulse-like acoustic wave. In the case of a three-dimensional sensor matrix, this is Frame rate upwards ultimately only by the maximum The repetition frequency of the pulse-like acoustic waves is limited is. The use of a three-dimensional sensor matrix offers also the advantage that the picture is free of any Be is motion artifacts that must necessarily occur when generating more than one pulse-like acoustic wave an image is required. The use of multiple impulses like acoustic waves could then be necessary at most if the object is of such a size that it image created the dimensions of the three-dimensional sensor matrix exceeds and thus a shift of the sensor matrix and of the object relative to each other is required to be a full to enable permanent mapping of the object. Even in that In this case, however, a few impulsive acoustic signals are sufficient Waves to create the entire spatial image.

The three-dimensional sensor matrix can be adjusted according to a wide range ren preferred embodiment on technically particularly simple way to realize when as a multilayer arrangement of each divided into several pressure sensors, piezoelectric activated and provided with electrodes polyvinylidene fluoride (PVDF) films is executed.

Such films are commercially available and can be found in in a known manner easily in such a way with Elek troden provided that there is a two-dimensional sensor matrix  results. Several such two-dimensional sensor matrices are available then, for example by gluing, to a three-dimensional one Sensor matrix connected in the form of a multilayer arrangement.

To enable adaptation to different conditions lichen, it can be useful if the focus of the impulsarti towards acoustic waves relative to the imaging lens is storable. In this case, according to a variant, the inven tion provided that the imaging lens as a variable lens cher focal length is executed, the focal length at Verla the focus of the impulsive acoustic waves is adjusted that the object focal point of the Abbil at least essentially in the focus of the impulse types against acoustic waves.

The imaging lens can be in the form of a material one Imaging lenses are completely eliminated if they are replaced by an ent speaking, implemented in the imaging electronics Simulation algorithm is formed. Through such a simu lations algorithm can also be in the presence of an Ab fixed focal length educational lens change an imaging lens simulate focal length. Such from radiation optics algorithms known per se are based on the fact that, when known nis the spatial pressure distribution and the way of spreading of the reflected parts of the pulse-like acoustic waves is easily possible by using the refractive law zes to calculate the pressure distribution that results would, if an imaging lens is certain acoustic Properties in the propagation path of the reflected parts would find.

According to a variant of the invention it is provided that the Source of acoustic waves Shock waves as impulsive acousti generated waves. Shock waves are acoustical  pressure impulses with an extremely steep rise front.

The part of the task relating to a therapy facility becomes solved according to the invention by a therapy device for Treatment of an object in a patient's body tes with focused acoustic waves, which a source fo kissed acoustic waves and as a locating device for Locating an object to be treated with an ultrasound image dungseinrichtung according to any one of claims 1 to 7, where at the source of focused acoustic waves both those for Treating focused acoustic waves as well the impulsive acoustic worlds used for image generation len generates and in the picture a the current position of the Focus zone of the focused acoustic treatment Brand indicating waves is shown. Because the location device of the therapy device according to the invention a three created dimensional image, there is additional information available to the therapy facility and the body of the patient align treating patients relative to each other in such a way that there is an optimal location of the object to be treated in the Focus zone of the focused acoustic treatment Waves. Thus, it is more effective and for the patient gentler treatment possible. There are special advantages then when the focus zone of the focus serving for treatment acoustic waves were small against the object to be treated is and an exposure to tissue outside of the object to be treated must be avoided. Based on the case the therapy device according to the invention are available the three-dimensional image information is namely reliable casual and easy possible, the focus zone for the Treatment-focused acoustic waves and the To shift patients or the object relative to each other, that the focus zone is only the object to be treated "scans". A major advantage is that the location  device is able to produce images in quick succession, so that any relocations of the patient or to be object immediately relative to the therapy facility is reflected in the three-dimensional image information find and can thus be taken into account in the therapy.

According to a variant of the invention is an acoustic lens provided an area for focusing the treatment acoustic waves and the imaging lens has forming area. In less expensive and constructive A single component simply takes over the radio tion of the focusing device for treatment serving focused acoustic waves and imaging lens.

A particularly preferred embodiment of the invention provides before that the imaging lens and the ultrasonic sensor means form a unit against the ultrasound head, in particular the sector scanner, an ultrasound locating device is interchangeable. This way it is possible if needed trap in a conventional manner using a conventional Lichen ultrasound tracking device to work.

Embodiments of the invention are in the accompanying Drawings shown. It shows

Fig. 1 is a perspective rough schematic representation of a imaging device according to the invention,

Fig. 2 shows a schematic representation of the ultrasonic sensor having tel of the imaging device shown in FIG. 1 and the circuit diagram corresponding to image generation electronics in the form of a block,

Fig. 3 in the Fig. 2 view of a variant of the analog Ul traschall sensor means and the associated Bilderzeu supply electronics,

Fig. 4 is an imaging device according to the invention as a location device containing therapy device in longitudinal section in a rough schematic representation, and

Fig. 5 shows a variant of the therapy device in accordance with Fig. 4.

The imaging device according to FIG. 1 has a spherical curved concave piezoelectric transducer as the source 1 of acoustic waves, which generates converging pulse-like acoustic waves in a focus F, the outer edge rays of which are designated RS1. The focus F is the center of curvature of the piezoelectric transducer. The focus F lies on the acoustic axis A of the arrangement, to which the source 1 is at least essentially rotationally symmetrical. The source 1 is designed such that a surrounding the acoustic axis A, approximately conical, of acoustic waves at least substantially free space is present, as shown in Fig. 1 by the inner marginal rays RS2 of the acoustic source 1 Waves is indicated. The space free of acoustic waves can either be realized in that the source 1 , as shown in FIG. 1, is provided with a central opening 2 , or in that in the central region of the source 1 there is no radiation of acoustic waves .

An acoustic imaging lens 3 is arranged in the space free of acoustic waves, the acoustic axis of which is identical to the acoustic axis A of the source 1 . The focal point of the imaging lens 3 lies in the area of the focus F of the acoustic waves emanating from the source 1 . In the area of the other focal point of the imaging lens, ultrasound sensor means 4 are arranged, which emit corresponding output signals corresponding to the spatial distribution of the pressure of the reflected from an object O, through the imaging lens 3 portions of the acoustic waves generated by the source I.

The output signals of the ultrasonic sensor means 4 , the education from which will be described in more detail in connection with FIGS . 2 and 3, are supplied to imaging electronics 5 which, based on the output signals of the ultrasonic sensor means 4, produce a true-to-scale, three-dimensional image of the object 8 is calculated and shown in perspective or two-dimensional on display means, namely a monitor 6 .

It is understood that between the object to be imaged O egg on the one hand and the source 1 or the imaging lens 3 and the ultrasound sensor means 4 on the other hand there must be an acoustic coupling. This can be provided, for example, in that the source 1 , the imaging lens 3 and the ultrasound sensor means 4 as well as the object O to be imaged or an object or living being containing the object O to be imaged in a manner known per se, not shown in detail Bath are included, which holds a liquid, such as water, ent as an acoustic propagation medium. However, there is also the possibility, in a manner not shown, of accommodating the source 1 , the imaging lens 3 and the ultrasound sensor means 4 in a housing filled with a suitable acoustic propagation medium, which is closed in a manner known per se with a preferably flexible application membrane, which is provided for contact with the object O to be imaged or an object or patient containing the object O to be imaged.

In order to be able to control the source 1 in the required manner for the output pulse-like acoustic waves, an elec trical pulse generator 7 is provided which acts on the source I with electrical pulses. Each time such a pulse is applied, the source 1 emits an acoustic pressure pulse, which sets up on its way through the acoustic propagation medium to form a so-called shock wave. A shock wave is a pressure pulse with an extremely steep rise front. The pulse generator 7 is connected via a trigger line 8 to the imaging electronics 5 and acts upon the arrival of a trigger pulse generated by the imaging electronics 5 , the source 1 with an electrical pulse.

The structure of the ultrasonic sensor means 4 and the imaging electronics 5 is shown in Fig. 2 in more detail. The ultrasonic sensor means 4 is a spatial 4 × 4 × 4 sensor matrix which is constructed from four piezoelectrically activated PVDF films 9 a to 9 d. Each of the PVDF films is provided on its front side in the illustration in FIG. 2 with four strip-shaped column electrodes which run at regular intervals from one another and parallel to one another and which are designated 10 a to 13 a in the case of the PVDF film 9 a. On the back of the PVDF foils 9 a to 9 d are four strip-shaped row electrodes, which are arranged at mutually parallel distances from one another. The PVDF film 9 a are indicated by dashed lines and designated 14 a to 17 a. The row electrodes 14 a to 17 a run at an angle of 90 ° to the column electrodes 10 a to 13 a and overlap with the column electrodes 10 a to 13 a in the areas hatched in FIG. 1. The PVDF films 9 b to 9 d are provided with column and row electrodes in a manner analogous to the PVDF film 9 a. Incidentally, the row and column electrodes are preferably metallizations applied in strips to the respective PVDF film. The areas shaded in FIG. 2 act in a manner known per se as piezoelectric pressure sensors, the output signals of the individual pressure sensors being able to be tapped between that column electrode and that row electrode which overlap in the area of the respective pressure sensor.

The PVDF films 9 a to 9 d are interposed with insulating layers, not shown in FIG. 2, which prevent short circuits between electrodes between adjacent PVDF films, preferably by bonding to a multilayer arrangement. The arrangement is such that there is a spatially regular arrangement of the pressure sensors, in such a way that the centers of the pressure sensors are at the intersection of the grid lines of a spatial cubic grid.

The column electrodes of the PVDF films 9 a to 9 d can be connected to ground via a 4: 1 analog multiplexer 18 , in such a way that, counted from the left, either all of the first, second, third or fourth column electrodes In order to be able to read out the output signals from the pressure sensors, four 4: 1 analog multiplexers 18 to 22 are also provided, the inputs of which are connected to the row electrodes of one of the PVDF foils 9 a to 9 d. The outputs of the Mul tiplexer 19 to 22 are connected to the inputs of a further 4: 1 analog multiplexer 23 , the output of which is connected to the input of an amplifier 24 . The output signal of the amplifier 24 is fed to an analog / digital converter 25 . Its digital output data are fed to an electronic computing and control unit 26 to which the monitor 6 is connected. The computing and control unit 26 also generates the trigger pulses for the pulse generator 7 , which are supplied to it via the trigger line 8 . In addition, the computing and control unit 26 generates clock signals which are fed via a control line 27 to a multiplexer controller 28 , which controls the multiplexers 18 to 23 via control lines 29 to 34 .

The control of the multiplexers 18 to 23 takes place in such a way that, following the generation of a shock wave by means of the source i, the output signals of all pressure sensors after a period which approximately corresponds to the duration of the shock wave from the source 1 to the focus F. continuously queried in succession, converted into digital data by means of the analog / digital converter 25 and supplied to the computing and control unit 26 which temporarily stores this data. From the data received following the generation of a shock wave, the computing and control unit 26 calculates a three-dimensional image of the object to be imaged, which is finally displayed on the monitor 6 , based on algorithms known per se from algorithms.

Since it is by the reception of the to be imaged Object reflected portions of the generated by the source l output signals of the sensor matrix transient signals, it is necessary that the Clock frequency with which the reading of the output signals of the Sensor matrix and its analog / digital conversion take place extremely high, namely in the MHz range.

The processing speed can be increased if the multiplexer 23 is omitted and each of the multiplexers 19 to 22 is followed by an amplifier and an analog / digital converter. A further increase of the processing is rate possible if each of the PVDF-foils 9 a to 9 d a plurality of analog / are assigned to digital converter, wherein each weils an analog / digital converter sensors for a group of haw, in extreme cases, only a only pressure sensor that is too constant.

According to FIG. 3, instead of a three-dimensional sensor matrix as described in connection with FIG. 2, a two-dimensional sensor matrix can be used. This then contains a single PVDF film 35 , provided with electrodes in a manner analogous to FIG. 2, which is attached to a suitable carrier 36 in the manner roughly schematically indicated in the side view in FIG. 3. In each case one of the column electrodes not visible in FIG. 3 can be connected to ground via a 4: 1 analog multiplexer 38 . In each case one of the row electrodes, which is likewise not visible, can be connected via a 4: 1 analog multiplexer 39 to an amplifier 40 , the output signals of which are fed to an analog / digital converter 41 . Whose digital output data are again fed to an electronic computing and control unit which bears the reference 42 and to which the monitor 6 is connected. The control and arithmetic unit 42 generates the trigger pulses for the pulse generator 7 , which are fed to it via the control line 8 . In addition, the control and arithmetic unit generates the control pulses for the multiplexers 38 and 39 , which are supplied via control lines 43 and 44 .

The reading of the output signals of the pressure sensors of the PVDF film 35 is carried out analogously to the manner described in connection with FIG. 2. In order to be able to detect the spatial distribution of the pressure of the parts of the shock wave reflected on an object to be imaged, although the PVDF film 35 is only a two-dimensional sensor matrix, adjustment means 43 are provided which allow the PVDF Slide 35 in the direction of the acoustic axis A relative to the imaging lens 3 to move, as indicated by the double arrow x. If the PVDF film 35 as in the present case is a regular two-dimensional 4 x 4 sensor array, it is expedient, the PVDF film 35 by means of the adjustment means 43, in such a way to be adjusted, that they can assume four positions which are selected in such a that there is a spatially regular arrangement of the centers of the pressure sensors, which again lie at the intersection of the grid lines of a spatial cubic grid.

The adjusting means 45 are actuated via a control line 46 by the computing and control unit 42 , in such a way that they are adjusted in each case before delivery of a shock wave in the next position. That is, wave at output of the first impact is the PVDF film 35, for example in their entferntesten from the imaging lens 3 position from which they before delivery of a shock wave in each case in which the imaging lens 3 next closer position is adjusted until it closes Lich before the fourth shock wave is brought into its next position in the imaging lens 3 . For each of the positions, the output signals are read out in a manner analogous to FIG. 2 and, after analog / digital conversion, are temporarily stored in the computing and control unit 42 , which finally calculates the three-dimensional image and displays it on the monitor 6 .

From the above it is clear that the ultrasonic sensor means 4 according to FIG. 3, in contrast to those according to FIG. 2, do not allow the three-dimensional image of the object to be imaged to be generated on the basis of the reflected portions of a single shock wave. Rather, a number of shock waves is required, which corresponds to the number of positions of the two-dimensional sensor matrix, ie the PVDF film 35 . It becomes clear that an imaging device using ultrasound sensor means 4 according to FIG. 3 must therefore work more slowly than an imaging device that contains the ultrasound sensor means 4 according to FIG. 2. As has already been explained above, it is also ensured in the case of the variant according to FIG. 3 that the three-dimensional images can be created in real time and thus much faster than in the prior art.

In Fig. 4, a therapy device is shown, which includes an imaging device of the type previously described as a location device. The therapy device is used to treat a patient with focused acoustic waves, in the case of the described embodiment, focused shock waves. Shock waves are used, for example, for the non-invasive destruction of concrements such as e.g. B. kidney stones are used. The therapy device accordingly contains a schematically indicated shock wave source 47 , which is, for example, an electromagnetic shock wave source of the type described in EP-A-0 188 750. The shock wave source 47 generates flat shock waves which are focused by means of an acoustic converging lens 48 onto a focus zone designated FZ. In order to be able to align the therapy device and the body of a patient relative to one another in such a way that an object to be acted on with the shock waves he generates, for example a kidney stone, is located in the focus zone FZ of the shock waves, the therapy device contains an ultrasound location device which, as already mentioned, is an imaging device of the type described above. To generate the pulse-like acoustic waves required for image generation, however, no special source for generating such waves is provided. Rather, the elec trical pulse generator 7 is designed such that it applies the shock wave source 47 for generating therapeutic purposes to the nend shock waves with current pulses of high intensity and for generating shock waves for imaging purposes with Stromim pulses of lower intensity. The corresponding switchover takes place via a control line 49 , via which the pulse generator 7 is connected to a control unit 50 , which at the same time also contains the imaging electronics.

The shock wave source 47 is of annular shape and accordingly has a central opening in which the ultrasonic sensor means 4 are received, which are thus in a space free from shock waves.

As a result of the space free from shock waves, there is the possibility of forming the central region of the converging lens 48 as an imaging lens 3 . The converging lens 48 and the imaging lens 3 then form a single common lens body 51 . The imaging lens 3 is shaped such that its focal point F is located in the center of the focus zone FZ.

The control unit 50 has a switch 58 with which the therapy device can optionally be switched to localization or therapy mode. In the locating mode, the control unit 50 controls the pulse generator 7 in such a way that it only generates low-intensity shock waves. The images generated on the basis of the portions of the shock wave of low intensity reflected on an object to be treated are displayed on the monitor 6 , the control unit 50 displaying a mark F 'in the images, which indicates the position of the center of the focus zone FZ. In the locating operation, the therapy device is now aligned relative to the body B of a patient to be treated so that the image of the object to be treated, for example the stone S of a kidney K with the brand F 'coincides. In this case, the stone S is, as shown in FIG. 4, in the area of the focus zone FZ.

If this is guaranteed, switch 58 can be used to switch to therapy mode. In therapy operation, a shock wave of high intensity is alternately generated in order to achieve the desired therapeutic effect, for example crushing the stone S. Following each shock wave or a preselectable number of shock waves of high intensity, an image of the area S to be treated is made and at least one shock wave of low intensity is emitted and displayed on the monitor 6 . In this way, continuous monitoring of the treatment process is possible. The shock wave source 47 , the converging lens 48 and the imaging lens 3 forming lens body 51 and the sensor means 4 are incidentally accommodated in a housing which is filled with a suitable acoustic propagation medium, for example water, and at its end of application by means of a flexible coupling membrane 53 is sealed liquid-tight. The coupling membrane 53 serves to press the therapy device for acoustic coupling to the body B of the patient as shown in FIG. 4.

The therapy device shown in Fig. 5 differs from that previously described in that the collecting lens 48 has an aligned with the shock wave source 47 central opening. A tube 54 extends through this and is connected to the housing 52 in a liquid-tight manner. In this, an imaging head 55 can optionally be inserted, which is filled with a suitable acoustic propagation medium and contains the imaging lens 3 and the ultrasound sensor means 4 . There is a provided between the ultrasonic sensor means 4 and the control unit 50 switch 56 in the position shown and the imaging head 55 is inserted into the tube 54 , the therapy device can be operated in the manner described in connection with FIG. 4 . If the switch 56 is brought into its other position and, instead of the imaging head 55, an ultrasound sector applicator 57 having the same dimensions is inserted into the tube 54 , conventional B-mode ultrasound images are generated instead of the spatial ultrasound images and displayed on the monitor 6 .

In the case of FIG. 5, the imaging lens 3 is only shown in broken lines. This is to illustrate that it is possible to omit the imaging lens 3 and to reproduce it by an algorithm implemented in the imaging electronics. This possibility exists not only in the case of the therapy device according to FIG. 5, but also in the devices according to FIGS. 1 to 3 and 4.

The described in connection with the embodiments 4 × 4 × 4 sensor matrix or 4 × 4 adjustable in four positions Sensor matrix is only to be understood as an example. Higher resolution Solutions are easily possible, the ones for reading the Output signals from the pressure sensors required multiplexer Arrangement of the respective resolution is easy to adjust.

In the case of the exemplary embodiments described, the three-dimensional image is calculated by the computing and control unit 26 . But there is also the possibility of a three-dimensional image, similar to conventional ultrasound devices, e.g. B. by time window of the output signals of the sensor matrix.

The exemplary embodiments which relate to therapy facilities refer to the treatment of a patient with focussed shock waves. It goes without saying that therapy facilities are also available that other focused acoustic waves to other be send out purposes of action, e.g. B. ultrasonic waves in the case of Hyperthermia can be designed according to the invention.

Claims (10)

1. Ultrasonic imaging device for imaging an object (O), having

• a) a source ( 1 ) of acoustic waves which generates pulse-like acoustic waves converging in a focus (F),
• b) an acoustic imaging lens ( 3 ) whose object-side focal point lies in the area of the focus (F) of the acoustic waves,
• c) Ultrasound sensor means ( 4 ) with an at least two-dimensional sensor matrix, which is arranged in the region of the focal point of the imaging lens ( 3 ) on the image side and which reflects the spatial distribution of the pressure of the object (O) to be imaged, through the imaging lens ( 3 ) give off corresponding electrical output signals to parts of the acoustic waves that have entered,
• d) an electronic imaging system ( 5 ) to which the output signals of the ultrasonic sensor means ( 4 ) are fed and which generates a true-to-scale, real, three-dimensional image of the object (O) on the basis of the output signals, and
• e) display means ( 6 ) which display the image, preferably in perspective or in two dimensions.

2. Imaging device according to claim 1, characterized in that the ultrasonic sensor means ( 4 ) have a flat sensor array divided into a plurality, preferably regularly arranged pressure sensors, and means for adjusting the distance between the sensor matrix and the imaging lens ( 3 ). 3. Imaging device according to claim 1, characterized in that the ultrasonic sensor means ( 4 ) are designed as a three-dimensional sensor matrix which contains a preferably regular spatial arrangement of pressure sensors. 4. Imaging device according to claim 3, characterized characterized that the three-dimensional Sen sormatrix as a multilayer arrangement of several each Pressure sensors divided, piezoelectrically activated and with Electrode-provided polyvinylidene fluoride films is. 5. Imaging device according to one of claims 1 to 4, characterized in that the focus (F) of the pulse-like acoustic waves relative to the imaging lens ( 3 ) is displaceable, and that the imaging lens ( 3 ) is designed as a lens of variable focal length, whose focal length is adjusted during the shift of the focus (F) of the pulse-like acoustic waves in such a way that the object-side focus of the imaging lens ( 3 ) lies at least essentially in the focus of the pulse-like acoustic waves. 6. Imaging device according to one of claims 1 to 5, characterized in that the imaging lens is formed by a simulation algorithm implemented in the imaging electronics ( 5 ). 7. Imaging device according to one of claims 1 to 6, characterized in that the source ( 1 ) generates acoustic waves as pulse-like waves shock waves. 8. Therapy device for treating an object (S) located in the body (B) of a patient with focused acoustic waves, which is a source ( 47 ) of focused acoustic waves and as a locating device for locating an object to be treated (S) according to an ultrasound imaging device Contains one of claims 1 to 7, wherein the source ( 47 ) of focused acoustic waves generates both the focused acoustic waves used for treatment and the pulse-like acoustic waves used for image generation, and wherein the current position of the focus zone (FZ) of the mark indicating treatment of focused acoustic waves is faded in. 9. Therapy device according to claim 8, characterized in that an acoustic lens ( 51 ) is provided which has an area ( 48 ) for focusing the acoustic waves used for treatment and an imaging lens ( 3 ) forming area. 10. Therapy device according to claim 8, that the imaging lens ( 3 ) and the ultrasonic sensor means ( 4 ) form a unit that is interchangeable with the ultrasound head, in particular the sector scanner ( 57 ), an ultrasound locating device.