Acoustic wave therapy apparatus

Abstract: In an acoustic wave therapy apparatus, a holder (100) is provided with an irradiation device for generating acoustic waves for medical treatment, and a bag (10) having a variable size and containing an acoustic wave propaga­ tion medium. The holder is also provided with a probe rod (30) having at its one end an ultrasonic probe for ultra­ sonic tomographic imaging. The probe rod has at least one opening (32, 34) at its one end. A pipe (40, 42) is connected to the opening of the probe rod. The pipe is connected to fluid equipment (400) for supplying/discharging the acoustic wave propagation medium into/from the bag member. The holder is held by a hand-type holding apparatus. A connector for connecting/disconnecting the pipe is arranged on a C-arm included in the hand-type holding apparatus.

Description: The present invention relates to an acoustic wave therapy apparatus according to the pre-characterizing part of claim 1. Conventional acoustic wave treatment apparatuses include an ultrasonic shock wave lithotrity apparatus for breaking calculi, etc. in a human body, using shock waves due to focusing ultrasonic energy, and an ultrasonic continuous wave hyperthermic therapy apparatus for treating a tumor by heating it up to a lethal temperature, using continuous focusing ultrasonic energy. This type of acoustic wave treatment apparatus generally has an irradiation device for generating ultrasonic waves. The irradiation device has a concave surface for focusing the generated ultrasonic waves. The acoustic wave generator is arranged to face a subject, with a bag interposed therebetween. An ultrasonic imaging probe is arranged within the bag, for positioning the irradiation device and for obtaining tomograms of the subject for confirming the result of treatment. If a large-diameter acoustic wave generator is employed in this apparatus and generated waves are focused onto a region-of-interest (ROI), a maximum treatment effect is attained with a small treatment energy. In this case, however, if the focus of waves departs from the ROI, a normal tissue is damaged. It is thus important to precisely focus the waves onto the ROI. Fig. 1 is a cross-sectional view for schematically showing a structure of an applicator serving as an important part of an acoustic wave therapy apparatus having this type of imaging means. In Fig. 1, ultrasonic transducers 2 serving as an irradiation device are secured to a holder 4 having a concave surface. The ultrasonic transducers 2 are arranged symmetrical in respect of a probe rod 16 (described later) so that the focal points of the transducers 2 may be positioned at a region-of-interest (ROI) 6. The acoustic wave therapy apparatus has a bag 10 containing water 8 which is put in close contact with a patient 12. The probe rod 16 having an ultrasonic probe 14 is arranged at the center of the holder 4. The ultrasonic probe 14 effects positioning for treatment by means of an image display process, thereby confirming if the ROI 6 has been treated appropriately. In Fig. 1, a dot-and-dash line indicates a region 18 where ultrasonic waves for treatment are radiated, and a two-dot-and-dash line indicates a region 20 (a tomogram display region) where ultrasonic waves for ultrasonic imaging are radiated. When an acoustic wave therapy is performed by this apparatus, a tomogram is formed on the basis of a reflected wave signal received by the ultrasonic probe 14. Observing the tomograms, an operator moves the apparatus so that the focal points of the ultrasonic transducers 2 may coincide with the location of the ROI 6, or positions the apparatus by supplying water 8 into and letting water 8 out of the bag 10. When the focal points of the transducers 2 have coincided with the location of the ROI 6, the transducers 2 are driven, e.g. by intense pulse waves to radiate intense ultrasonic waves onto the ROI 6, thereby subjecting the ROI 6 to, e.g. lithotri The positioning of the focal points of the transducers 2 relative to the ROI 6 will now be described. The size of the bag 10 is adjusted by supplying the water 8 thereinto and letting out the water 8 therefrom. Thus, the focal points of the transducers 2 can be freely positioned relative to the ROI 6. The water 8 is supplied into and discharged from the bag 10 through a pipe (not shown) arranged above the holder 4 or the bag 10. In the above apparatus, however, the water 8 in the bag 10 cannot completely be discharged from the bag 10 since the water 8 is discharged through the pipe arranged above the holder 4 or the bag 10. As a result, the water 8 would remain on the bottom of the bag 10, and the ultrasonic probe 14 is always put in the water 8. This leads to deterioration of characteristics of the ultrasonic probe 14. The object of the present invention is to provide an acoustic wave therapy apparatus capable of exactly treating a region-of-interest, without deteriorating the characteristics of an ultrasonic probe. According to the invention, this is achieved by the characterizing features of claim 1. This invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which: Fig. 1 is a cross-sectional view schematically showing an example of an important portion of a conventional acoustic wave therapy apparatus; Fig. 2 is a perspective view showing an overall structure of an acoustic wave therapy apparatus according to an embodiment of the present invention; Fig. 3 is a cross-sectional view schematically showing the state of connection between an applicator and a C-arm in the embodiment shown in Fig. 2, wherein pipes, etc. are omitted; Fig.4 is a cross-sectional view schematically showing an important portion (applicator) in the same embodiment; Fig. 5 is a perspective view showing an end portion of a probe rod in the same embodiment; Fig. 6 shows an example of arrangement of pipes for connecting the applicator and water equipment in the same embodiment; Fig. 7 is a block diagram showing an electric circuit in the case where the embodiment shown in Fig. 2 has been applied to an ultrasonic shock wave lithotrity apparatus; Figs. 8A to 8C show operation modes of water equipment, in which Fig. 8A illustrates a water supply mode, Fig. 8B a water circulation mode, and Fig. 8C a water discharge mode; Figs. 9A and 9B show an applicator and a tomogram in the case where the bag member of the applicator has been contracted by the discharge operation of the water equipment, in which Fig. 9A is a cross-sectional view illustrating the relationship between the applicator and the patient, and Fig. 9B shows a tomogram displayed on a monitor; Figs. 10A and 10B show an applicator and a tomogram in the case where the bag member of the applicator has been swelled by the supply operation of the water equipment, in which Fig. 10A is a cross-sectional view illustrating the relationship between the applicator and the patient, and Fig. 10B shows a tomogram displayed on a monitor; Fig. 11 is a block diagram showing an electric circuit in the case where the embodiment shown in Fig. 2 has been applied to an ultrasonic continuous wave hyperthermic therapy apparatus; Fig. 12 shows another example of arrangement of pipes for connecting the applicator shown in Fig. 4 and water equipment; and Fig. 13 shows an example of arrangement of pipes for connecting an applicator, different from that shown in Fig. 4, and water equipment. The structure of an acoustic wave therapy apparatus according an embodiment of the present invention will now be described with reference to accompanying Figs. 2 to 7. Referring to Figs. 2 and 3, the overall structure of the apparatus will be described. A holder 4, which is a part of an applicator 100, is held by a holding apparatus 200. The holding apparatus 200 comprises a base 202 set on the floor and provided, desirably, with casters, a column 204 vertically arranged on the base 202, a C-arm mounted slidably on the column 204, and a holding mechanism provided on the C-arm 206 for holding the holder 4. The holding mechanism 208 comprises, for example, a ball and socket joint mechanism. As is shown in Fig. 3, ball members 208-1 are provided on both side portions 4-1 and 4-2 of the holder 4, socket members 208-2 are provided on mutually facing arm portions 206-1 and 206-2 of the C-arm 206. Since the C-arm 206 for holding the applicator 100 is slidable on the column 204 in the direction indicated by a double-headed arrow 212, the applicator 100 can be placed at a desirable height. In addition, as shown in Fig. 2, the applicator 10 can be inclined in the direction indicated by a double-headed arrow 210. Accordingly, the application can be approached to a desired location on a patient (not shown). The applicator 100 is connected to electric equipment 300 over a cable 302 for feeding signals for driving the ultrasonic imaging probe 14. In addition, the applicator 100 is connected to water equipment 400 through three pipes 402 for supply and discharge of water and air. The cable 302 and pipes 402 can be disconnected by means of a connector 500 mounted on the C-arm 206. The connector 500 comprises a plug portion 500-1 for connection with shorter pipes (denoted by 40 and 42 in Fig. 4) extending from the applicator 100, and a socket portion 500-2 secured to the C-arm 206. The plug portion 500-1 is removable from the socket portion 500-2. Namely, by disconnection of the connector 50, a probe unit 600 comprising a probe rod 30 and shorter cables and pipes 302 and 402 can be separated from the applicator 100 and the holding apparatus 200. It is possible to prepare a number of probe units 600 having different frequency characteristics for tomographic imaging, and to use a suitable one of the units 600 in accordance with a region-of-interest. As a result, optimum tomographic imaging can be carried out, and reliable medial treatment can be performed. Referring to Figs. 4 and 6, the applicator 100 and the probe rod 30 will now be described in detail. In the applicator 100, a holder 4 having a concave surface is provided with ultrasonic transducers 2 serving as an irradiation device, and a bag 10 containing water 8. The bag member 10 consists of a flexible water bag (diaphragm) 10-1 and a bellows 10-2. Since the holder 4 has a concave surface, the medical treatment ultrasonic waves (pulse waves or continuous waves) emitted from the ultrasonic transducers 2 can be focused at a focal point determined by the shape of the concave surface of the holder 4. The holder 4 has a through-hole at its central portion. The probe rod 30 is inserted into the through-hole of the holder 4 and arranged vertically movable in the bag member 10. Otherwise, the holder 4 may have a through-hole at the other portion. The bag member 10 is put in close contact with the patient 12. The size of the bag member 10 can be varied by increasing/decreasing the amount of water 8 contained in the bag member 10. Namely, the medical treatment ultrasonic waves can be focused at a desired point in the patient 12, by varying the size of the bag member 10 put in close contact with the patient 12. An ultrasonic probe 14 is provided at an end portion of the probe rod 30. Water ports 32 and 34 are provided in the vicinity of the ultrasonic probe 14. For example, the port 32 serves as a suction port, and the port 34 serves as a supply port. Water passages 36 and 38 extend along the longitudinal axis of the probe rod 30. The passages 36 and 38 are connected at one end to the water ports 32 and 34 and connected at the other end, e.g. to first ends of the pipes 40 and 42. The second ends of the pipes 40 and 42 are connected to the plug portion 500-1 of the connector 500 shown in Fig. 2. A pipe 44, through which air is supplied to or discharged from the inside of the applicator 100, is arranged above the holder 4. The passages 36 and 38 extending along the longitudinal axis of the probe rod 30 may be replaced with two pipes extending similarly along the longitudinal axis of the probe rod 30. According to an example shown in Fig. 5, the water ports 32 and 34 are formed not at the wave transmitting/receiving face (the end portion of the probe rod 30) of the ultrasonic probe 14, but a little above the end portion of the ultrasonic probe 14. Of course, the water ports 32 and 34 may be formed at the the wave transmitting/receiving face (the end portion of the probe rod 30). Referring to Fig. 6, the water equipment connected to the socket portion 500-2 of the connector 500 will now be described. The water equipment 400 comprises pipes 402 for interconnecting various valves (described later), an electromagnetic valve (MV1) 404-1, an electromagnetic valve (MV2) 404-2, an electromagnetic valve (MV3) 404-3, an electromagnetic valve (MV4) 404-4, a three-way valve (TV1) 406-1, a three-way valve (TV2) 406-2, a pump (P) 408, a temperature controller (H) 410, a water tank 412, a vacuum pump (VP) 430 for sucking air from the applicator 100, and a compression pump (CP) 432 for supplying air into the applicator 100. It is desirable that the temperature controller (H) 410 be arranged midway along the passage for supplying, circulating and discharging water, as shown in Fig. 6. Fig. 7 illustrates an electric circuit of the electric equipment 300 and the water equipment 400. The electric circuit of the electric equipment 300 comprises a pulse wave driver (PWD) 302 for pulse-driving the ultrasonic transducers 2, a transmitter/receiver 304 for enabling the ultrasonic probe 14 to transmit/receive ultrasonic waves for tomographic imaging, a reconstruction device (REC) 306 for producing a tomogram on the basis of a signal output from the transmitter/receiver 304, a monitor 308 for displaying the tomogram produced by the reconstruction device 306, a controller 310 for controlling the transmitter/receiver 304 and the pulse-wave driver 302, a CPU 312 for controlling the controller 310, and a console 314 for supplying a command to the CPU 312. In the above embodiment, the ultrasonic transducers 2 are driven by high-voltage pulses applied from the PWD 302, thereby generating shock waves for lithotrity. However, the ultrasonic transducers 2 may be driven by a driver (not shown) with a low power, so that envelope data is obtained from the received echo. The envelope data contributes greatly to enhance the precision of coincidence between the region-of-interest and the focal point of shock waves for lithotrity. The electric circuit of the water equipment 400 comprises valve drivers (VD1, VD2, VD3 an VD4) 414-1, 414-2, 414-3 and 414-4, three-way valve drivers (TD1 and TD2) 416-1 and 416-2, a pump driver (PD) 418, a temperature control driver (HD) 420, a vacuum pump driver (VPD) 434 for driving the vacuum pump 430, a compression pump driver (CPD) 436 for driving the compression pump 432, a water controller 422 for controlling these drivers, and a console 424 for supplying commands to the water controller 422. The operation of the above-described embodiment will now be described with reference to Figs. 8A to 8C, Figs. 9A to 9B, and Figs. 10A and 10B. Fig. 8A illustrates a water supply mode of the acoustic wave therapy apparatus. In the water supply mode, the electromagnetic valves 404-1 and 404-4 are opened and the electromagnetic valves 404-2 and 404-3 are closed by the operation of the water controller 422. Thus, the pump 408 is operated. The water 8 is supplied from the tank 412 into the applicator 100 through the pipes 402, 40 and 42, thereby swelling the bag member 10. Fig. 8A illustrates a water circulation mode of the apparatus. In the water circulation mode, the electromagnetic valves 404-3 and 404-4 are closed and the electromagnetic valves 404-1 and 404-2 are opened by the operation of the water controller 422. Thus, the pump 408 is operated. The water 8 in the applicator 100 can be circulated through the pipes 402, 40 and 42. In this case, the water 8 in the applicator 100 can be cooled or heated by actuating the temperature controller (HD) 410 and the driver 420. Fig. 8C illustrates a water discharge mode of the apparatus. In the water discharge mode, the electromagnetic valves 404-1 and 404-4 are closed and the electromagnetic valves 404-2 and 404-3 are opened by the operation of the water controller 422. Thus, the pump 408 is operated. The water 8 is discharged from the applicator 100 to the tank 412 through the pipes 402, 40 and 42. Thus, the bag member 10 is contracted. According to this apparatus, the water 8 in the bag member 10 can be discharged almost completely, by virtue of the water ports 32 and 34 formed at the probe rod 30. Even if a small amount of water 8 remains on the bottom of the bag member 10, the ultrasonic probe 14 is not immersed in the water 8, and the characteristics of the probe 14 are not degraded. Of course, if the water ports 32 and 34 are formed at the lowest part of the probe rod 30, the water 8 can be discharged completely. This makes easier the cleaning of the inside of the applicator 100 and the replacement of the bag member 10. In the water supply mode, water circulation mode, and water discharge mode, the vacuum pump 430 or the compression pump 432 is operated suitably. In the water supply mode, the amount of air, which corresponds to the amount of water to be supplied, is discharged. In the water discharge mode, the amount of air, which corresponds to the amount of water to be discharge, is supplied. Thus, the bag member 10 is prevented from deformation, while the length of the bellows 10-2 is kept unchanged. In addition, it is easy to discharge the water 8 from the applicator 100 completely, and to replace the bag member 10. By virtue of the above-described water supply mode and the water discharge mode, the focal point of the medical treatment acoustic waves can be made to coincide with a region-of-interest (ROI) in the patient 12. More specifically, Fig. 9A shows the case where the applicator 100 is put on the patient 12 but the amount of water 8 in the applicator 100 is insufficient. In this case, as shown in Fig. 9B, a marker " " 316A representing a focal point 316 departs from an image 6A representing the ROI 6, in an image 20A shown on a screen 308A of the monitor 308. In order to make the focal pint 316 coincide with the ROI 6, the water 8 is supplied into the bag member 10 of the applicator 100 in the water supply mode. As a result, as shown in Fig. 10A, the focal point 316 coincides with the ROI 6. On the screen 308A shown in Fig. 10B, too, it is confirmed that the marker " " 316A representing the focal point 316 coincides with the image 6A representing the ROI 6. Fig. 11 shows a case where the acoustic wave therapy apparatus shown in Figs. 2 to 6 is employed as an ultrasonic continuous wave hyperthermic therapy apparatus. In this case, the pulse wave driver (PWD) 302 is replaced with a continuous wave driver (CWD) 318. Referring to Fig. 12, a description will now be given of a modification of the water equipment of the acoustic wave therapy apparatus shown in Figs. 2 to 5. In this modification, a four-way valve 426 is arranged midway along the pipes 402, and the four-way valve 426 is controlled by a driver (not shown) and the water controller 422. By virtue of this structure, it becomes possible to use the water ports 32 and 34 and passages 40 and 42 simultaneously for supplying water, and also to use them simultaneously for discharging water. Thus, the water supply/discharge performance can be doubly enhanced. Referring to Fig. 13, a description will now be given of a modification of the applicator 100 of the acoustic wave therapy apparatus shown in Figs. 2 to 6. In this applicator, one water port 32 is formed at the probe rod 30, and the other water port 34 is formed at the holder 4. This makes the structure of the probe rod 30 simpler. The cables 302 and pipes 402 may be arranged in order by means of a simple holder, without using the connector 500 which allows the disconnection of the cables 302 and pipes 402.

Claims: An acoustic wave therapy apparatus characterized by comprising: a holder (4) having a concave surface at least on one side thereof, and also having a through-hole; acoustic wave generating means (2), provided on said one side of said holder (4), for generating acoustic waves for medical treatment; a bag member (10) arranged on said one side of the holder (4) and designed to be put in contact with the surface of a subject, and containing an acoustic wave propagation medium (8), the size of said bag member (10) being variable to accommodate said propagation medium which is supplied/discharged into/from said bag member (10) through a pipe member (36, 38, 40, 42, 404) by supply/discharge means (400); a rod member (30) inserted in to said through-hole of the holder (4) and arranged vertically movable in said bag member (10); and an ultrasonic probe (14) for ultrasonic wave tomographic imaging, provided at the bag member-side (10) end portion of the rod member (30), characterized in that said rod member (30) has at least one opening at said end portion, the pipe member (36, 38, 40, 42, 404) extends inside the rod member (30) along its longitudinal axis and is connected to the opening. The apparatus according to claim 1, characterized in that said acoustic wave generating means (2) is adapted to generate high-intensity pulse waves for lithotrity. The apparatus according to claim 1, characterized in that said acoustic wave generating means (2) is adapted to generate high-intensity continuous waves for hyperthermic therapy. The apparatus according to claim 1, characterized in that said acoustic wave propagation medium (8) is water. The apparatus according to claim 1, characterized in that said supply/discharge means (400) includes means for heating the medium (8). The apparatus according to claim 1, characterized in that said supply/discharge means (400) includes circulation means (402, 404-1, 404-2, 404-3, 404-4, 406-1, 406-2, 406, 412) for circulating the acoustic wave propagation medium (8) in the bag member (10) by supplying/discharging the acoustic wave propagation medium (8) into/from the bag member (10). The apparatus according to claim 1, characterized in that said supply/discharge means (400) includes heating means (410), provided midway along the pipe member (36, 38, 40, 42), for heating the acoustic wave propagation medium (8). The apparatus according to claim 1, characterized in that said supply/discharge means (400) includes an air supply/discharge member, for supplying and discharging air into and from the inside of the bag member (10). The apparatus according to claim 1, characterized in that said holder (4) is held by a holding apparatus (200) comprising a base (202) set on the floor, a column (204) vertically arranged in the base (202), a C-arm (206) mounted slidably on the column (204), and a holding mechanism (208) provided on the C-arm (206) for holding the holder (4). The apparatus according to claim 10, characterized in that said holding mechanism (208) comprises a ball-and socket joint mechanism (208-1, 208-2). The apparatus according to claim 10, characterized in that a connector (500) is secured on said C-arm (206), for connecting/disconnecting at least said pipe (404). The apparatus according to claim 1, characterized in that said rod member (30) has a plurality of openings, there are provided a plurality of pipes (36, 38, 40, 42) connected to the openings. The apparatus according to claim 12, characterized in that said supply/discharge means (400) includes fluid equipment connected to said plurality of pipes (36, 38, 40, 42). The apparatus according to claim 13, characterized in that said fluid equipment (400) includes an air supply/discharge member, for supplying and discharging air into and from the inside of the bag member (100). The apparatus according to claim 13, characterized in that said fluid equipment (400) includes pipe (402), flow rate control valves (404-1, 404-2, 404-3, 404-4), direction change valves (406-1, 406-2, 426), a pump (408), a tank (412), and circulation means (414, 416, 418) for circulating the acoustic wave propagation medium (8) in the bog member (10) by a supply/discharge operation. The apparatus according to claim 13, characterized in that said fluid equipment (400) includes heating means (410, 420), provided midway along the pipes, for heating the acoustic wave propagation medium (8). The apparatus according to claim 13, characterized in that said fluid equipment (400) includes cooling means (410, 420), provided midway along the pipes, for cooling the acoustic wave propagation medium (8).

Inventors: KUDO NOBUKI C O INTELLECTUCAL, NOMURA SATOSHI C O INTELLECTUC, KUDO, NOBUKI, C/O INTELLECTUCAL PROPERTY DIVISION, NOMURA, SATOSHI, C/O INTELLECTUCAL PROPERTY DIV.
Applicants: TOSHIBA KK, KABUSHIKI KAISHA TOSHIBA
Application year: 1990
Main classification: A61B17
IPC codes: A61F7, A61B17, A61B18, A61B8