Ultrasonic treatment device

Abstract

To facilitate confirmation that an affected part is irradiated with a therapeutic ultrasonic wave in the therapy using an ultrasonic therapeutic device.SOLUTION: In therapeutic ultrasonic wave transmission processing, an ultrasonic vibrator 28 is caused to transmit a therapeutic ultrasonic wave 38. In irradiation region image generation processing, a plurality of imaging pulses 46 are transmitted to an ultrasonic probe 16 at different timings and by different phases as a plurality of ultrasonic waves after the therapeutic ultrasonic wave 38 is transmitted, and reflected by a biological tissue, and a plurality of reception signals based on a plurality of the reflected ultrasonic waves received by the ultrasonic probe 16 are added and totalled so that irradiation region data based on a non-linear component of each reception signal is generated. In assistance ultrasonic wave transmission processing, the ultrasonic vibrator 28 is caused to transmit an interleave pulse 50 at a timing between two timings at which two imaging pulses adjacent to each other on a temporal axis of the plurality of imaging pulses 46 are transmitted.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an ultrasonic treatment apparatus, and more particularly to an apparatus including an ultrasonic vibrator for treatment and an ultrasonic probe for image generation.

Background Art

[0002] Treatment apparatuses using high-density focused ultrasound therapy are widely used. This ultrasonic treatment apparatus is referred to as a HIFU irradiation apparatus or a HIFU irradiation system (High Intensity Focused Ultrasound), and irradiates ultrasonic waves to a treatment site to necrotize tissue.

[0003] Generally, a HIFU irradiation apparatus includes a plurality of ultrasonic vibrators arranged on a bowl-shaped surface. The plurality of ultrasonic vibrators are arranged such that ultrasonic waves emitted from each of them are irradiated to a single point to form a focus. During treatment, the position of the focus is adjusted to the treatment site and ultrasonic waves are irradiated. For confirmation of the irradiation position, an ultrasonic imaging apparatus that represents the focus on an ultrasonic image is used.

[0004] Patent Document 1 below describes an ultrasonic treatment apparatus that observes the position of a focus using an ultrasonic imaging apparatus that displays a B-mode image (tomographic image). In this apparatus, weak-level ultrasonic waves that do not affect the tissue are emitted from the ultrasonic vibrator for treatment, and a tomographic image is displayed by transmitting and receiving ultrasonic waves with an ultrasonic imaging probe. Since the acoustic characteristics of the tissue of the subject change according to the temperature change of the tissue, the position of the focus is indicated by the intensity of the brightness in the tomographic image.

[0005] Patent Document 2 describes, as a technique related to the present invention, a technique for visualizing an echo component generated by scattering with a microbubble-based contrast agent by discriminating it from a component generated by non-linear propagation of a transmission pulse.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Laid-Open No. 8-71069 [Patent Document 2] International Publication No. 2005 / 087109 [Patent Document 3] Japanese Patent Laid-Open No. 2023-79320 [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] Generally, when strong therapeutic ultrasonic waves are irradiated on the affected part of a living tissue, bubbles (cavities) are generated at the irradiated location by cavitation. In the treatment using a conventional HIFU irradiation device, as a method for confirming that the therapeutic ultrasonic waves have been irradiated on the affected part, there are those based on the observation of the positions of the bubbles generated by cavitation and the observation of the patient's living tissue. The observation of the positions of the bubbles is performed, for example, by harmonic imaging in which ultrasonic waves are transmitted from an ultrasonic probe toward the affected part and the harmonic waves generated from around the bubbles are received by the ultrasonic probe as described in Patent Document 3. Also, the observation of the patient's living tissue is performed by acquiring a B-mode image by transmitting and receiving ultrasonic waves with an ultrasonic probe.

[0008] In the treatment using a HIFU irradiation device, for example, when the area of the affected part is narrow, the therapeutic ultrasonic waves are irradiated in a narrow range. Therefore, due to the small amount of bubbles generated, it may be difficult to confirm that the therapeutic ultrasonic waves have been irradiated on the affected part.

[0009] An object of the present invention is to facilitate confirmation that therapeutic ultrasonic waves have been irradiated on the affected part in the treatment using an ultrasonic treatment device. [Means for Solving the Problems]

[0010] The present invention includes a therapeutic ultrasonic transducer, an ultrasonic probe, and a control unit that controls the ultrasonic transducer and the ultrasonic probe. The control unit executes a therapeutic ultrasonic transmission process for repeatedly transmitting therapeutic ultrasonic waves to the ultrasonic transducer, an auxiliary ultrasonic transmission process for transmitting auxiliary ultrasonic waves to the ultrasonic transducer, and irradiates a plurality of ultrasonic waves to the ultrasonic probe at different timings and different phases during an irradiation pause period while the therapeutic ultrasonic waves are repeatedly transmitted, reflects them from a biological tissue, and synthesizes a plurality of received signals based on the plurality of reflected ultrasonic waves received by the ultrasonic probe, thereby generating irradiation region data based on a non-linear component of each received signal, that is, an irradiation region image generation process. In the auxiliary ultrasonic transmission process, the auxiliary ultrasonic waves are transmitted to the ultrasonic transducer at a timing between two timings at which two adjacent ultrasonic waves among the plurality of ultrasonic waves that are the targets to be synthesized, which are the sources of the plurality of received signals synthesized in the irradiation region image generation process, are transmitted on the time axis. , increase the non-linear component The method is characterized by including the above process.

[0011] Preferably, the auxiliary ultrasonic transmission process of the synthesis target includes a process of transmitting the auxiliary ultrasonic waves to the ultrasonic transducer at a timing earlier than an intermediate timing between two timings at which two adjacent ultrasonic waves among the plurality of ultrasonic waves are transmitted on the time axis.

[0012] Preferably, the auxiliary ultrasonic transmission process includes a process of transmitting the auxiliary ultrasonic waves to the ultrasonic transducer at a timing earlier than the plurality of ultrasonic waves after the therapeutic ultrasonic waves are transmitted. of the synthesis target Preferably, the plurality of received signals are signals based on a plurality of reflected ultrasonic waves received by the ultrasonic probe based on M ultrasonic waves sequentially transmitted from the ultrasonic probe with a phase difference of 360° / M.

[0013] of the synthesis target M kinds ultra

[0014] ​​Preferably, the control unit executes a B-mode image generation process for generating B-mode image data of the biological tissue using any one of the plurality of received signals.

[0015] Preferably, the control unit causes a display device to display an irradiation area image based on the irradiation area data and a B-mode image based on the B-mode image data.

[0016] Preferably, the control unit overlaps to represent the irradiation area image based on the irradiation area data and the B-mode image based on the B-mode image data and causes the display device to display them.

Advantages of the Invention

[0017] According to the present invention, it is possible to easily confirm that the therapeutic ultrasonic wave has been irradiated to the affected part.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0019] Embodiments of the present invention will be described with reference to the respective figures. The same reference numerals are assigned to the same components shown in a plurality of drawings to simplify the description. FIG. 1 shows the configuration of a HIFU irradiation device 100 (ultrasonic treatment device) according to an embodiment of the present invention. The HIFU irradiation device 100 includes a HIFU vibrator unit 10, a HIFU drive circuit 14, an ultrasonic probe 16, a transmission / reception circuit 18, an imaging calculation unit 20, a controller 22, a display device 24, and a drive device 26.

[0020] The controller 22 may be a personal computer, a tablet computer, or the like. An operation device (not shown) for the user to operate the HIFU irradiation device 100 is connected to the controller 22. The operation device may include a mouse, a touch panel integrated with the display device 24, a switch, a keyboard, or the like.

[0021] The HIFU vibrator unit 10 includes a vibrator housing 12 having a concave surface 4 with an opening facing downward, and a plurality of ultrasonic vibrators 28 arranged along the concave surface 4 in the vibrator housing 12 and fixed to the vibrator housing 12. The HIFU vibrator unit 10 does not necessarily have a physical concave surface 4. In this case, the plurality of ultrasonic vibrators 28 may be fixed to the vibrator housing 12 so as to be arranged along a virtual concave surface 4.

[0022] The concave surface 4 of the vibrator housing 12 may have a shape similar to the side surface of a cone. Here, a cone refers to a three-dimensional shape formed by a set of straight lines extending from a point in space to a bottom surface. Further, the concave surface 4 of the vibrator housing 12 may have a shape that bulges upward in a dome shape. Each ultrasonic vibrator 28 is fixed to the vibrator housing 12 so that when each ultrasonic vibrator 28 emits ultrasonic waves, the intensity of the ultrasonic waves is enhanced at the focal point F below the vibrator housing 12.

[0023] The HIFU driving circuit 14 generates ultrasonic waves in each ultrasonic vibrator 28 included in the HIFU vibrator unit 10 in accordance with the control of the controller 22. Further, the HIFU driving circuit 14 adjusts the intensity of the ultrasonic waves generated by each ultrasonic vibrator 28 in accordance with the control of the controller 22.

[0024] The ultrasonic probe 16 is fixed to the vibrator housing 12 so that ultrasonic waves are transmitted and received at a position below the vibrator housing 12 and above the focal point F. In the present embodiment, the ultrasonic probe 16 penetrates the vertex portion of the vibrator housing 12 in the vertical direction, and the transmission / reception unit 2 for transmitting and receiving ultrasonic waves is directed downward.

[0025] A general ultrasonic imaging device may be used for the transmission / reception circuit 18 and the imaging calculation unit 20. The imaging calculation unit 20 may be configured by a processor that executes a program to control the transmission / reception circuit 18. The transmission / reception circuit 18 executes the following processes in accordance with the control of the imaging calculation unit 20. That is, the transmission / reception circuit 18 causes the ultrasonic probe 16 to transmit ultrasonic waves and scans a beam (ultrasonic beam) formed by the transmitted ultrasonic waves. The ultrasonic beam is scanned on an observation plane including the central axis 3 extending vertically from the vertex portion of the vibrator housing 12. The transmission / reception circuit 18 causes the ultrasonic probe 16 to receive the reflected ultrasonic waves arriving from the direction in which the ultrasonic beam is directed, and acquires a reception signal based on the reflected ultrasonic waves received from each direction in which the ultrasonic beam is directed from the ultrasonic probe 16. The transmission / reception circuit 18 outputs each reception signal to the imaging calculation unit 20.

[0026] The imaging calculation unit 20 generates ultrasonic data based on each reception signal output from the transmission / reception circuit 18. The ultrasonic data may be irradiation region data indicating a region where a non-linear component has occurred in the biological tissue of the patient, or B-mode image data indicating a B-mode image (tomographic image) acquired for the biological tissue of the patient.

[0027] The drive device 26 moves the HIFU oscillator unit 10 and the ultrasonic probe 16 and adjusts their positions according to the control of the controller 22. Further, the drive device 26 may rotate the ultrasonic probe 16 around the central axis 3 according to the control of the controller 22, and rotate the observation surface of the ultrasonic probe 16 around the central axis 3.

[0028] Before the therapeutic ultrasonic wave is irradiated from the HIFU oscillator unit 10 to the patient, the following positioning process is executed. The HIFU drive circuit 14 causes each ultrasonic oscillator 28 to transmit an ultrasonic wave with a lower intensity than during treatment. The drive device 26 sets the rotation angle position of the ultrasonic probe 16 so that the ultrasonic probe 16 scans the ultrasonic beam on the observation surface at a predetermined rotation angle position.

[0029] The imaging calculation unit 20 scans the ultrasonic probe 16 with an ultrasonic beam on the observation surface, acquires B-mode image data as ultrasonic data, and outputs it to the controller 22. The controller 22 causes the B-mode image to be displayed on the display device 24. The user as the operator refers to the B-mode image displayed on the display device 24 and confirms the difference between the position where the ultrasonic wave transmitted from the HIFU oscillator unit 10 is intensified (focus) and the position of the affected part.

[0030] When the difference between the position of the focus F and the position of the affected part is not within the allowable range, the user changes the position or posture of the ultrasonic probe 16 and the HIFU oscillator unit 10. After the user confirms that the position of the focus F and the position of the affected part match, or the difference between the position of the focus F and the position of the affected part is within the allowable range, the user performs an operation for treatment on the controller 22. The controller 22 controls the HIFU drive circuit 14 according to the operation by the user. The HIFU drive circuit 14 causes each ultrasonic oscillator 28 to transmit a therapeutic ultrasonic wave having the intensity required for treatment according to the control by the controller 22. Thereby, the biological tissue is cauterized at the focus F and treatment is performed.

[0031] The HIFU irradiation device 100 executes an irradiation area display process that displays an image (irradiation area image) indicating the irradiation area irradiated with the therapeutic ultrasonic wave on the display device 24 while irradiating the patient with the therapeutic ultrasonic wave. The irradiation area image is an image indicated by the irradiation area data. The irradiation area image may be displayed side by side with the B-mode image, or may be displayed superimposed on the B-mode image. Here, the process of displaying two images superimposed may be a process of synthesizing image data so that one image is translucent and the other image is visible, generating new image data, and displaying an image based on the new image data.

[0032] FIG. 2 conceptually shows the transmission timings of the therapeutic ultrasonic wave 38 transmitted from the HIFU oscillator unit 10 and the HIFU / imaging hybrid wave 36 transmitted from the HIFU oscillator unit 10 and the ultrasonic probe 16 when the irradiation area display process is executed.

[0033] The therapeutic ultrasonic wave 38 is composed of a therapeutic ultrasonic wave pulse 44 including a trigger pulse 40 and a heating burst 42 following the trigger pulse 40. The therapeutic ultrasonic wave pulse 44 is repeatedly transmitted from the HIFU oscillator unit 10 over time. An irradiation pause period 48 is provided between adjacent therapeutic ultrasonic wave pulses 44 on the time axis, and during the irradiation pause period 48, the transmission of the therapeutic ultrasonic wave 38 is stopped. The amplitude of the heating burst 42 may be smaller than the amplitude of the trigger pulse 40. The time length T1 of the trigger pulse 40 may be shorter than the time length T3 of the heating burst 42.

[0034] When the therapeutic ultrasonic wave pulse 44 is transmitted from the HIFU oscillator unit 10, the biological tissue is cauterized at the focus F. While the trigger pulse 40 irradiates the biological tissue, bubbles are generated from the biological tissue, and the state in which bubbles are generated is maintained by the irradiation of the heating burst 42.

[0035] During the irradiation pause period 48, an HIFU / imaging hybrid wave 36 is transmitted from the HIFU oscillator unit 10 and the ultrasonic probe 16. The HIFU / imaging hybrid wave 36 includes a first imaging pulse 46-1, a second imaging pulse 46-2, and a third imaging pulse 46-3 transmitted from the ultrasonic probe 16 at time intervals of time τ0. The second imaging pulse 46-2 is 120° out of phase with respect to the first imaging pulse 46-1. The third imaging pulse 46-3 is 120° out of phase with respect to the second imaging pulse 46-2. In the following description, any one of the first imaging pulse 46-1 to the third imaging pulse 46-3 that is not specified may be referred to as an imaging pulse 46.

[0036] The HIFU / imaging hybrid wave 36 further includes a first interleaved pulse 50-1 and a second interleaved pulse 50-2 transmitted from the HIFU oscillator unit 10. In the following description, any one of the first interleaved pulse 50-1 and the second interleaved pulse 50-2 that is not specified may be referred to as an interleaved pulse 50.

[0037] The first interleaved pulse 50-1 is transmitted at a timing between two timings at which the first imaging pulse 46-1 and the second imaging pulse 46-2 are transmitted, and the second interleaved pulse 50-2 is transmitted at a timing between two timings at which the second imaging pulse 46-2 and the third imaging pulse 46-3 are transmitted.

[0038] Specifically, the first interleaved pulse 50-1 is transmitted when a time τ1 has elapsed after the first imaging pulse 46-1 is transmitted, and the second Imaging pulse 46-2 is transmitted. Also, when a time τ1 has elapsed after the second imaging pulse 46-2 is transmitted, the second interleaved pulse 50-2 is transmitted, and when a time τ2 has elapsed after the second interleaved pulse 50-2 is transmitted, the third Imaging pulse 46 -3 is transmitted.

[0039] The time τ1 is shorter than the time τ2. That is, the first interleaved pulse 50-1 is transmitted at a timing earlier than the intermediate timing between the timing at which the first imaging pulse 46-1 is transmitted and the timing at which the second imaging pulse 46-2 is transmitted. Here, the intermediate timing refers to the timing corresponding to the midpoint between two points on the time axis. Also, the second interleaved pulse 50-2 is transmitted at a timing earlier than the intermediate timing between the timing at which the second imaging pulse 46-2 is transmitted and the timing at which the third imaging pulse 46-3 is transmitted.

[0040] The times τ1 and τ2 may be determined such that the HIFU / imaging hybrid wave 36 acts on the biological tissue as follows. The first interleaved pulse 50-1 reaches the affected part after the reflected ultrasonic wave generated based on the first imaging pulse 46-1 is received by the ultrasonic probe 16 and vibrates the bubbles generated at the affected part. The second imaging pulse 46-2 reaches the affected part after the multiple reflection waves generated in the biological tissue by the first interleaved pulse 50-1 are sufficiently attenuated. The second interleaved pulse 50-2 reaches the affected part after the reflected ultrasonic wave generated based on the second imaging pulse 46-2 is received by the ultrasonic probe 16 and vibrates the bubbles generated at the affected part. The third imaging pulse 46-3 reaches the affected part after the multiple reflection waves generated in the biological tissue by the second interleaved pulse 50-2 are sufficiently attenuated.

[0041] Each interleaved pulse 50 may be composed of a single ultrasonic pulse or may be composed of a plurality of consecutive ultrasonic pulses on the time axis. In the lower right of FIG. 3, the timings of the respective ultrasonic pulses when the interleaved pulse 50 is composed of, in order from above, a single ultrasonic pulse, a three-wave ultrasonic pulse, and a ten-wave ultrasonic pulse are shown respectively.

[0042] In the example shown in FIG. 2, the time from when the first imaging pulse 46-1 is transmitted until the first interleaved pulse 50-1 is transmitted is equal to the time from when the second imaging pulse 46-2 is transmitted until the second interleaved pulse 50-2 is transmitted, but these times may be different.

[0043] Each imaging pulse 46 reflects within the biological tissue. When the imaging pulse 46 reflects around the bubbles generated by the therapeutic ultrasonic pulse 44, non-linear components such as harmonics are generated. Therefore, the reflected ultrasonic wave reflected from the biological tissue includes non-linear components caused by the bubbles in addition to the fundamental wave. Generally, the greater the amount of bubbles generated, the greater the intensity of the non-linear components generated.

[0044] Returning to FIG. 1, the process by which the HIFU irradiation device 100 receives the reflected ultrasonic wave for each imaging pulse 46 will be described. The ultrasonic probe 16 receives the first to third reflected ultrasonic waves for the first to third imaging pulses 46-1 to 46-3, and outputs the first to third received signals to the transmission / reception circuit 18 respectively. The transmission / reception circuit 18 performs amplification etc. on the first to third received signals and outputs them to the imaging operation unit 20.

[0045] The imaging operation unit 20 adds and sums the first to third received signals, and generates a non-linear signal obtained by adding and summing the non-linear components included in each of the first to third received signals. Due to the phase relationships of the first to third imaging pulses 46-1 to 46-3, the fundamental wave component is suppressed in the signal obtained by adding and summing the first to third received signals. The imaging operation unit 20 generates a non-linear signal for the first to third reflected ultrasonic waves arriving from each direction towards which the ultrasonic beam is directed, and generates irradiation region data based on the non-linear signals generated for each direction. The irradiation region data is image data indicating an irradiation region image showing the region where bubbles are generated among the regions scanned by the ultrasonic beam.

[0046] Also, the imaging operation unit 20 generates a B-mode image based on one of the first to third reflected ultrasonic waves. For example, the imaging operation unit 20 generates pixel data for the B-mode image in each direction based on the second reflected ultrasonic wave arriving from each direction towards which the ultrasonic beam is directed, and generates B-mode image data based on the pixel data obtained for each direction. Note that the reflected ultrasonic wave serving as the basis for the B-mode image data may be the first reflected ultrasonic wave or the third reflected ultrasonic wave.

[0047] The imaging operation unit 20 outputs the irradiation region data and the B-mode image data to the controller 22. The controller 22 causes the display device 24 to display an image (B-mode irradiation region image) in which the irradiation region image is superimposed on the B-mode image based on the irradiation region data and the B-mode image data.

[0048] The imaging operation unit 20 outputs the irradiation region data and the B-mode image data to the controller 22 at frame time intervals (the reciprocal of the frame rate). The controller 22 sequentially causes the display device 24 to display the B-mode irradiation region image as time elapses.

[0049] Note that the controller 22 may display the irradiation area image and the B-mode image separately without overlapping them. For example, the controller 22 may display the irradiation area image and the B-mode image side by side on the display device 24 so that they can be compared.

[0050] The experimental results are shown in FIG. 4. In the upper left and lower left of FIG. 4, the B-mode image and the irradiation area image are shown respectively for the case where the conventional basic imaging ultrasonic wave is used. The basic imaging ultrasonic wave is obtained by removing the first interleaved pulse 50-1 and the second interleaved pulse 50-2 from the HIFU / imaging hybrid wave 36. In the transmission of the basic imaging ultrasonic wave, when the first imaging pulse 46-1 is transmitted and then the first interleaved pulse 50-1 is not transmitted and the time τ0 has elapsed, the second imaging pulse 46-2 is transmitted. Further, when the second imaging pulse 46-2 is transmitted and then the second interleaved pulse 50-2 is not transmitted and the time τ0 has elapsed, the third imaging pulse 46-3 is transmitted. The horizontal axis in each drawing indicates the width [mm], and the vertical axis indicates the depth [mm]. The image of the bubble 60 appears in each image.

[0051] In the upper right and lower right of FIG. 4, the B-mode image and the irradiation area image are shown respectively for the present embodiment using the HIFU / imaging hybrid wave 36. As the interleaved pulse 50, one composed of three ultrasonic pulses consecutive on the time axis was used. The horizontal axis in each drawing indicates the width [mm], and the vertical axis indicates the depth [mm]. The image of the bubble 60 appears in each image. As is clear from the lower left figure and the lower right figure, the bubbles 60 generated in the irradiation area are more clearly shown when the HIFU / imaging hybrid wave 36 is used than when the basic imaging ultrasonic wave is used.

[0052] Figure 5 shows the bubble-to-tissue contrast ratio of the irradiation area image (hereinafter referred to as the contrast ratio). The contrast ratio when using the HIFU / imaging hybrid wave 36 is approximately 9 dB higher than the contrast ratio when using the basic imaging ultrasonic wave without using the interleaved pulse 50. The experimental conditions are as follows. The period T0 from transmitting the previous trigger pulse 40 to transmitting the next trigger pulse 40 is 50 msec. The time length T1 of the trigger pulse 40 is 0.1 msec. The time T2 from the end of transmitting the trigger pulse 40 to the start of transmitting the heating burst 42 is 3 msec. The time length T3 of the heating burst 42 is 43.9 ms ec is. The time T4 from the end of transmitting the heating burst 42 to the start of transmitting the HIFU / imaging hybrid wave 36 is 1 ms ec is. The time τ1 in the HIFU / imaging hybrid wave 36 is 120 μsec, and the time τ2 is 280 μsec. The irradiation pause period T5 is 3 msec.

[0053] Figure 6 shows the contrast ratios when the configurations of the HIFU / imaging hybrid wave 36 are different. From the first to the third from the left, the contrast ratios are shown in order for the case where the interleaved pulse 50 is composed of 10 high-intensity ultrasonic pulses, the case where it is composed of 3 high-intensity ultrasonic pulses, and the case where it is composed of 1 high-intensity pulse. From the fourth to the sixth from the left, the contrast ratios are shown in order for the case where the interleaved pulse 50 is composed of 10 medium-intensity ultrasonic pulses, the case where it is composed of 3 medium-intensity ultrasonic pulses, and the case where it is composed of 1 medium-intensity pulse. Here, the high-intensity ultrasonic pulse refers to the ultrasonic pulse when the amplitude is the same as that of the trigger pulse 40, and the medium-intensity ultrasonic pulse refers to the ultrasonic pulse when the amplitude is the same as that of the heating burst 42. On the far right, the contrast ratio when using the basic imaging ultrasonic wave is shown.

[0054] As shown in Fig. 6, the larger the amplitude of the interleaved pulse 50, the greater the tendency for the contrast ratio to increase. Also, the greater the number of ultrasonic pulses that make up the interleaved pulse 50, the greater the tendency for the contrast ratio to increase.

[0055] Thus, in the HIFU irradiation apparatus 100 according to this embodiment, by transmitting the HIFU / imaging hybrid wave 36, the first interleaved pulse 50-1 is transmitted between the transmission of the first imaging pulse 46-1 and the transmission of the second imaging pulse 46-2. When the first interleaved pulse 50-1 is transmitted to the affected area, the bubbles generated in the affected area by the therapeutic ultrasonic wave 38 vibrate, increasing the non-linear component generated by the second imaging pulse 46-2. Also, between the transmission of the second imaging pulse 46-2 and the transmission of the third imaging pulse 46-3, the second interleaved pulse 50-2 is transmitted. When the second interleaved pulse 50-2 is transmitted to the affected area, the bubbles generated in the affected area by the therapeutic ultrasonic wave 38 vibrate, increasing the non-linear component generated by the third imaging pulse 46-3. As a result, the magnitude of the non-linear signal increases, the bubbles shown in the irradiation area image are emphasized, and it becomes easier for the user to confirm that the therapeutic ultrasonic wave 38 has been irradiated to the affected area.

[0056] In the above, the process of transmitting the interleaved pulse 50 at the timing between two timings when two adjacent imaging pulses 46 on the time axis are transmitted was shown. The interleaved pulse 50 may be transmitted after the therapeutic ultrasonic pulse 44 is transmitted and before the first imaging pulse 46 is transmitted.

[0057] Also, in the above, the process of transmitting the imaging pulse 46 for generating ultrasonic data three times was shown. The imaging pulse 46 may be transmitted two or four or more times. When the imaging ultrasonic wave is transmitted M times (M is an integer of 2 or more), the phase difference between adjacent imaging pulses 46 on the time axis is set to 360° / M. Alternatively, regardless of the transmission order, the phase of each imaging ultrasonic wave may be set such that the phases of θ + i·360° / M (θ is an arbitrary phase, i is an integer from 0 to M - 1) are assigned to the M imaging pulses 46.

[0058] The imaging operation unit 20 adds and sums the first received signal to the Mth received signal, and generates a non-linear signal obtained by adding and summing the non-linear components included in each of the first received signal to the Mth received signal. Also, the imaging operation unit 20 generates a B-mode image based on one of the first reflected ultrasonic wave to the Mth reflected ultrasonic wave.

[0059] In the above, an embodiment was shown in which a pulse including the trigger pulse 40 and the heating burst 42 following the trigger pulse 40 was used as the therapeutic ultrasonic pulse 44. As the therapeutic ultrasonic pulse 44, a pulse including only the trigger pulse 40 and not including the heating burst 42 may be used.

[0060] FIG. 7 conceptually shows the transmission timing of the therapeutic ultrasonic pulse 44 not including the heating burst 42 and the HIFU / imaging hybrid wave 36. When the irradiation pause period T5 has elapsed after the transmission of the previous trigger pulse 40 has ended, the next trigger pulse 40 is transmitted. During the irradiation pause period T5, the HIFU / imaging hybrid wave 36 is transmitted when the time T4 has elapsed after the transmission of the trigger pulse 40 has ended.

[0061] Figure 8 shows the contrast ratio when using a therapeutic ultrasonic pulse 44 that does not include a heating burst 42. On the left side, the contrast ratio when using an interleaved pulse 50 with a HIFU / imaging hybrid wave 36 composed of three high-intensity ultrasonic pulses is shown. On the right side, the contrast ratio when using basic imaging ultrasonic waves is shown. The contrast ratio when using the HIFU / imaging hybrid wave 36 is approximately 6 dB greater than the contrast ratio when using basic imaging ultrasonic waves. Even when the therapeutic ultrasonic pulse 44 does not include a heating burst 42, similar to the case where the therapeutic ultrasonic pulse 44 includes a heating burst 42, the contrast ratio tends to be larger when using the HIFU / imaging hybrid wave 36 compared to when using basic imaging ultrasonic waves.

[0062] As described above, the HIFU irradiation device 100 is an ultrasonic treatment device including a HIFU oscillator unit 10 including a therapeutic ultrasonic oscillator 28, an ultrasonic probe 16, and a control unit 30 that controls the ultrasonic oscillator 28 and the ultrasonic probe 16. The control unit 30 is composed of a HIFU drive circuit 14, a transmission / reception circuit 18, an imaging calculation unit 20, and a controller 22.

[0063] The control unit 30 executes a therapeutic ultrasonic transmission process, an auxiliary ultrasonic transmission process, and an irradiation area image generation process. The therapeutic ultrasonic transmission process is a process of transmitting a therapeutic ultrasonic wave 38 to the ultrasonic oscillator 28. The irradiation area image generation process is a process executed after the therapeutic ultrasonic wave 38 is transmitted. The irradiation area image generation process is a process of transmitting a plurality of imaging pulses 46 as a plurality of ultrasonic waves to the ultrasonic probe 16 at different timings, reflecting from the biological tissue, and generating irradiation area data based on the non-linear component of each received signal by adding and summing (synthesizing) the first received signal to the Mth received signal (a plurality of received signals) of the first reflected ultrasonic wave to the Mth reflected ultrasonic wave (a plurality of reflected ultrasonic waves) received by the ultrasonic probe 16.

[0064] In addition, the auxiliary ultrasonic transmission process includes a process of causing the ultrasonic transducer 28 to transmit an interleaved pulse 50 as auxiliary ultrasonic waves at a timing between two timings at which two adjacent ones among a plurality of imaging pulses 46 are transmitted on the time axis.

[0065] In addition, the auxiliary ultrasonic transmission process may include a process of causing the ultrasonic transducer 28 to transmit an interleaved pulse 50 as auxiliary ultrasonic waves at a timing earlier than that of the plurality of imaging pulses 46 after the therapeutic ultrasonic wave 38 is transmitted.

[0066] The control unit 30 executes a B-mode image generation process for generating B-mode image data of biological tissue using any one of a plurality of received signals.

[0067] The control unit 30 executes a display process for causing the display device 24 to display an irradiation area image based on the irradiation area data and a B-mode image based on the B-mode image data. The control unit 30 may cause the display device 24 to display the irradiation area image and the B-mode image superimposed on each other.

[0068] According to such a configuration and process, the biological tissue is irradiated with the therapeutic ultrasonic wave 38, and the area irradiated with the therapeutic ultrasonic wave 38 is shown on the irradiation area image. This makes it easy for the user to confirm that the therapeutic ultrasonic wave 38 has been irradiated to the affected part. In addition, the transmission of the interleaved pulse 50 increases the non-linear component generated by the imaging pulse 46. As a result, the magnitude of the non-linear signal increases, the bubbles shown in the irradiation area image are emphasized, and it becomes easy for the user to confirm that the therapeutic ultrasonic wave 38 has been irradiated to the affected part.

[0069] Configuration 1: A therapeutic ultrasonic transducer, An ultrasonic probe, A control unit that controls the ultrasonic transducer and the ultrasonic probe, and The control unit is A therapeutic ultrasonic wave transmission process for causing the ultrasonic transducer to transmit a therapeutic ultrasonic wave, and An auxiliary ultrasonic wave transmission process for causing the ultrasonic oscillator to transmit an auxiliary ultrasonic wave, After the therapeutic ultrasonic wave is transmitted, a plurality of ultrasonic waves are transmitted to the ultrasonic probe at different timings and different phases, reflected by the biological tissue, and a plurality of received signals based on the plurality of reflected ultrasonic waves received by the ultrasonic probe are synthesized to generate irradiation region data based on the non-linear component of each received signal. An irradiation region image generation process, and execute, The auxiliary ultrasonic wave transmission process is, An ultrasonic therapy apparatus, characterized in that it includes a process of transmitting the auxiliary ultrasonic wave to the ultrasonic oscillator at a timing between two timings at which two adjacent ones of the plurality of ultrasonic waves are transmitted on the time axis. Configuration 2: The ultrasonic therapy apparatus according to Configuration 1, The auxiliary ultrasonic wave transmission process is, An ultrasonic therapy apparatus, characterized in that it includes a process of transmitting the auxiliary ultrasonic wave to the ultrasonic oscillator at a timing earlier than the intermediate timing between two timings at which two adjacent ones of the plurality of ultrasonic waves are transmitted on the time axis. Configuration 3: The ultrasonic therapy apparatus according to Configuration 1 or Configuration 2, The auxiliary ultrasonic wave transmission process is, An ultrasonic therapy apparatus, characterized in that it includes a process of transmitting the auxiliary ultrasonic wave to the ultrasonic oscillator at a timing earlier than the plurality of ultrasonic waves after the therapeutic ultrasonic wave is transmitted. Configuration 4: The ultrasonic therapy apparatus according to any one of Configurations 1 to 3, The plurality of received signals are signals based on a plurality of reflected ultrasonic waves received by the ultrasonic probe based on M ultrasonic waves sequentially transmitted from the ultrasonic probe with a phase difference of 360° / M. An ultrasonic therapy apparatus characterized by that. Configuration 5: structure The ultrasonic therapy apparatus according to any one of Configurations 1 to 4, The control unit An ultrasonic treatment apparatus, characterized in that it executes a B-mode image generation process for generating B-mode image data of the biological tissue by using any one of the plurality of received signals. Configuration 6: The ultrasonic treatment apparatus according to Configuration 5, wherein the control unit, displays an irradiation region image based on the irradiation region data and a B-mode image based on the B-mode image data on a display device. Configuration 7: The ultrasonic treatment apparatus according to Configuration 5, wherein the control unit, superimposes an irradiation region image based on the irradiation region data and a B-mode image based on the B-mode image data and displays the result on the display device.

Explanation of Reference Numerals

[0070] 2 Transmitting and receiving unit, 3 Central axis, 4 Concave surface, 10 HIFU oscillator unit, 14 HIFU drive circuit, 16 Ultrasonic probe, 18 Transmitting and receiving circuit, 20 Imaging operation unit, 22 Controller, 24 Display device, 26 Drive device, 28 Ultrasonic oscillator, 30 Control unit, 36 HIFU / Imaging hybrid wave, 38 Therapeutic ultrasonic wave, 40 Trigger pulse, 42 Heating burst, 44 Therapeutic ultrasonic pulse, 46-1 First imaging pulse, 46-2 Second imaging pulse, 46-3 Third imaging pulse, 48 Irradiation pause period, 50-1 First interleaved pulse (auxiliary ultrasonic wave), 50-2 Second interleaved pulse (auxiliary ultrasonic wave), 60 Bubble, 100 HIFU irradiation device (ultrasonic treatment apparatus).

Claims

1. A therapeutic ultrasonic vibrator, an ultrasonic probe, and a control unit that controls the ultrasonic vibrator and the ultrasonic probe, wherein the control unit performs a therapeutic ultrasonic wave transmission process for repeatedly transmitting therapeutic ultrasonic waves to the ultrasonic vibrator, performs an auxiliary ultrasonic wave transmission process for transmitting auxiliary ultrasonic waves to the ultrasonic vibrator, transmits a plurality of ultrasonic waves to the ultrasonic probe at different timings and different phases during an irradiation pause period while the therapeutic ultrasonic waves are repeatedly transmitted, reflects them from a biological tissue, and generates irradiation region data based on the non-linear component of each received signal by synthesizing a plurality of received signals based on the plurality of reflected ultrasonic waves received by the ultrasonic probe, wherein the auxiliary ultrasonic wave transmission process includes transmitting the auxiliary ultrasonic wave to the ultrasonic vibrator at a timing between two timings at which two adjacent ones of the plurality of ultrasonic waves that are the sources of the plurality of received signals synthesized in the irradiation region image generation process are transmitted, and a process of increasing the non-linear component. An ultrasonic treatment apparatus characterized by this.

2. The ultrasonic treatment apparatus according to claim 1, wherein the auxiliary ultrasonic wave transmission process includes transmitting the auxiliary ultrasonic wave to the ultrasonic vibrator at a timing earlier than the intermediate timing between two timings at which two adjacent ones of the plurality of ultrasonic waves that are the synthesis targets are transmitted. An ultrasonic treatment apparatus characterized by this.

3. The ultrasonic treatment apparatus according to claim 1 or claim 2, wherein the auxiliary ultrasonic wave transmission process includes transmitting the auxiliary ultrasonic wave to the ultrasonic vibrator at a timing earlier than the plurality of ultrasonic waves that are the synthesis targets after the therapeutic ultrasonic wave is transmitted. An ultrasonic treatment apparatus characterized by this.

4. The ultrasonic treatment apparatus according to claim 1 or claim 2, wherein the plurality of received signals are signals based on a plurality of reflected ultrasonic waves received by the ultrasonic probe based on M ultrasonic waves of the synthesis targets sequentially transmitted from the ultrasonic probe with a phase difference of 360° / M. An ultrasonic treatment apparatus characterized by this.

5. The ultrasonic treatment apparatus according to claim 1 or claim 2, wherein the control unit performs a B-mode image generation process for generating B-mode image data of the biological tissue using any one of the plurality of received signals. An ultrasonic treatment apparatus characterized by this.

6. The ultrasonic treatment device according to claim 5, wherein the control unit causes a display device to display an irradiation area image based on the irradiation area data and a B-mode image based on the B-mode image data.

7. The ultrasonic treatment device according to claim 5, wherein the control unit causes a display device to display, in an overlapping manner, an irradiation area image based on the irradiation area data and a B-mode image based on the B-mode image data.

Images