HIFU irradiation device

Abstract

To facilitate an operation to match the position of a focal point of an ultrasonic wave for treatment to a treatment part in a high intensity focused ultrasound (HIFU) irradiation device.SOLUTION: A vibrator control unit 18 controls a plurality of ultrasonic vibrators 32 arranged along a recessed surface 30. A probe driving unit 14 rotates an ultrasonic probe 12 arranged on a central axis 40 of the recessed surface 30 around the central axis 40. A data acquisition unit 16 acquires B mode image data by the ultrasonic probe 12. A controller 22 controls the vibrator control unit 18, the probe driving unit 14, and the data acquisition unit 16. The controller 22 executes processing to search for a focal point F of an ultrasonic wave emitted from the plurality of ultrasonic vibrators 32 on a B mode image indicated by the B mode image data while changing a rotation angle position of the ultrasonic probe 12 around the central axis 40 when the plurality of ultrasonic vibrators 32 are caused to transmit the ultrasonic wave.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a HIFU irradiation device and a focus adjustment method thereof, and in particular to adjustment of the position of the focus using a B-mode image. [Background technology]

[0002] A treatment device using high intensity focused ultrasound is widely used. This treatment device is called a HIFU irradiation device or HIFU irradiation system, and necrotizes biological tissue by irradiating a treatment site with focused ultrasound.

[0003] In general, a HIFU irradiation device is equipped with a plurality of ultrasonic transducers for treatment arranged along a concave surface. The plurality of ultrasonic transducers are arranged so that ultrasonic waves emitted from each of them are irradiated to one point to form a focal point. During treatment, the position of the focal point is adjusted to the treatment area and ultrasonic waves are irradiated. To confirm the irradiation position, an ultrasonic diagnostic device that shows the focal point on an ultrasonic image is used.

[0004] The following Patent Document 1 describes an ultrasonic treatment device that observes the position of the focal point using an ultrasonic diagnostic device that displays a B-mode image (tomographic image). In this device, a therapeutic ultrasonic transducer emits ultrasonic waves at a low level that do not affect tissue, and an ultrasonic imaging probe transmits and receives ultrasonic waves to display a tomographic image. Since the acoustic properties of the patient's tissue change according to changes in the tissue temperature, the position of the focal point is indicated in the tomographic image by changes in brightness. Also, as shown in Non-Patent Document 1, the irradiation of ultrasonic waves causes displacement in the patient's tissue, and therefore the position of the focal point is indicated in the tomographic image by changes in brightness. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-71069 [Non-patent literature]

[0006] [Non-Patent Document 1] Tissue hardness measurement using ARFI Internet<https: / / www.innervision.co.jp / sp / ad / suite / siemens / technical_notes / 140368> Summary of the Invention [Problem to be solved by the invention]

[0007] In treatment using high-intensity focused ultrasound, if there is an area in the patient's tissue that has different acoustic properties from the surrounding area, the refraction of the ultrasound emitted from the therapeutic ultrasound transducer may cause the focal position to shift compared to when the acoustic properties are uniform. This can cause the ultrasound focus to not appear on the B-mode image, making it difficult to adjust the focal position of the therapeutic ultrasound to the treatment area.

[0008] An object of the present invention is to facilitate the operation of adjusting the focal position of therapeutic ultrasound to a treatment site in a HIFU irradiation device. [Means for solving the problem]

[0009] The HIFU irradiation device according to the present invention includes a transducer control unit that controls a plurality of ultrasonic transducers arranged along a concave surface, a probe driving unit that rotates an ultrasonic probe arranged on a central axis of the concave surface around the central axis, a data acquisition unit that acquires B-mode image data by the ultrasonic probe, and a controller that controls the transducer control unit, the probe driving unit, and the data acquisition unit, and the controller executes a process of searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while changing a rotation angle position of the ultrasonic probe around the central axis when the plurality of ultrasonic transducers are transmitting ultrasonic waves, and a process of stopping the ultrasonic probe at the rotation angle position when the focal point is detected.

[0010] Desirably, the controller adjusts the delay time of the ultrasound emitted from each of the multiple ultrasonic transducers while keeping the ultrasonic probe stationary at the rotational angle position when the focal point is detected, to move the focal point closer to the central axis or position the focal point on the central axis.

[0011] Further, the HIFU irradiation device according to the present invention includes a transducer control unit that controls a plurality of ultrasonic transducers arranged along a concave surface, an ultrasonic transducer driving unit that rotates the plurality of ultrasonic transducers around a central axis of the concave surface, a data acquisition unit that acquires B-mode image data by an ultrasonic probe arranged on the central axis of the concave surface, and a controller that controls the transducer control unit, the ultrasonic transducer driving unit, and the data acquisition unit, and the controller executes a process of searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while changing rotation angle positions of the plurality of ultrasonic transducers around the central axis when the plurality of ultrasonic transducers are caused to transmit ultrasonic waves, and a process of stopping the plurality of ultrasonic transducers at the rotation angle position when the focal points are detected.

[0012] Desirably, the controller adjusts the delay time of the ultrasound emitted from each of the multiple ultrasonic transducers while keeping the multiple ultrasonic transducers stationary at the rotational angle position when the focal point is detected, to move the focal point closer to the central axis or position the focal point on the central axis.

[0013] Further, the HIFU irradiation device according to the present invention includes a transducer control unit which controls a plurality of ultrasonic transducers arranged along a concave surface, a data acquisition unit which acquires B-mode image data by an ultrasonic probe arranged on a central axis of the concave surface, and a controller which controls the transducer control unit and the data acquisition unit, and the controller executes a process of searching for a focus of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while adjusting a delay time of ultrasonic waves emitted from each of the plurality of ultrasonic transducers when the plurality of ultrasonic transducers are made to transmit ultrasonic waves.

[0014] Desirably, ultrasonic waves are generated from each of the plurality of ultrasonic transducers at the delay time when the focus is detected, and then the delay time of the ultrasonic waves emitted from each of the plurality of ultrasonic transducers is adjusted to bring the focus closer to the central axis or to position the focus on the central axis.

[0015] The present invention is also a focus adjustment method for a HIFU irradiation device including a plurality of ultrasonic transducers arranged along a concave surface, an ultrasonic probe arranged on a central axis of the concave surface and rotatably around the central axis, and a data acquisition unit that acquires B-mode image data by the ultrasonic probe, the focus adjustment method including the steps of: searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while changing a rotation angle position of the ultrasonic probe around the central axis when ultrasonic waves are transmitted from the plurality of ultrasonic transducers; and stopping the ultrasonic probe at the rotation angle position when the focal point is detected.

[0016] Desirably, the method includes a step of adjusting the delay time of each ultrasonic wave emitted from the plurality of ultrasonic transducers while keeping the ultrasonic probe stationary at the rotational angle position when the focal point is detected, to bring the focal point closer to the central axis or to position the focal point on the central axis.

[0017] The present invention is also a focus adjustment method for a HIFU irradiation device including a plurality of ultrasonic transducers arranged along a concave surface, the plurality of ultrasonic transducers being rotatably arranged around a central axis of the concave surface, an ultrasonic probe arranged on the central axis of the concave surface, and a data acquisition unit acquiring B-mode image data by the ultrasonic probe, the focus adjustment method including the steps of: searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while changing rotation angle positions of the plurality of ultrasonic transducers around the central axis when ultrasonic waves are transmitted from the plurality of ultrasonic transducers; and stopping the plurality of ultrasonic transducers at the rotation angle positions when the focal points are detected.

[0018] Desirably, the method includes a step of adjusting the delay time of each ultrasonic wave emitted from the multiple ultrasonic transducers while keeping the multiple ultrasonic transducers stationary at the rotational angle position when the focal point is detected, to bring the focal point closer to the central axis or to position the focal point on the central axis.

[0019] The present invention is also a focus adjustment method for a HIFU irradiation device including a plurality of ultrasonic transducers arranged along a concave surface, and a data acquisition unit for acquiring B-mode image data by an ultrasonic probe arranged on a central axis of the concave surface, the focus adjustment method including a step of searching for a focus of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image shown by the B-mode image data while adjusting a delay time of ultrasonic waves emitted from each of the plurality of ultrasonic transducers when ultrasonic waves are transmitted from the plurality of ultrasonic transducers.

[0020] Desirably, the method includes a step of generating ultrasound from each of the plurality of ultrasonic transducers with the delay time when the focus is detected, and then adjusting the delay time of the ultrasound emitted from each of the plurality of ultrasonic transducers to bring the focus closer to the central axis or to position the focus on the central axis. Effect of the Invention

[0021] According to the present invention, the operation of adjusting the focal position of therapeutic ultrasound to the treatment site can be facilitated. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing the configuration of a HIFU irradiation device according to a first embodiment. [Diagram 2] FIG. 11 is a diagram illustrating a focus adjustment process. [Diagram 3] FIG. 11 is a diagram illustrating a focus adjustment process. [Figure 4] FIG. 11 is a diagram illustrating a focus adjustment process. [Diagram 5] FIG. 11 is a diagram showing the configuration of a HIFU irradiation apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] An embodiment of the present invention will be described with reference to each drawing. The same components shown in multiple drawings are given the same reference numerals to simplify the description. Fig. 1 shows the configuration of a HIFU irradiation device 100 according to a first embodiment of the present invention. The HIFU irradiation device 100 includes a HIFU transducer unit 10, an ultrasonic probe 12, a coupling bag 24, a probe driver 14, a data acquisition unit 16, a transducer control unit 18, a display unit 20, and a controller 22.

[0024] 1 shows a cross section of the HIFU transducer unit 10. The HIFU transducer unit 10 includes a transducer housing 26 having a concave surface 30 with an opening facing downward, and a plurality of ultrasonic transducers 32 arranged along the concave surface 30 in the transducer housing 26 and fixed to the transducer housing 26. The HIFU transducer unit 10 does not necessarily have to have a substantial concave surface 30. In this case, the plurality of ultrasonic transducers 32 may be fixed to the transducer housing 26 so as to be arranged along a virtual concave surface.

[0025] The concave surface 30 of the transducer housing 26 may have a shape similar to that of a side surface of a pyramid. Here, a pyramid refers to a three-dimensional shape formed by a collection of straight lines extending from one point in space to the bottom surface. The concave surface 30 of the transducer housing 26 may also have a shape that bulges out like a dome on the upper side. Each ultrasonic transducer 32 is fixed to the transducer housing 26 so that when each ultrasonic transducer 32 emits ultrasonic waves, the intensity of the ultrasonic waves is intensified at a treatment reference point P below the transducer housing 26.

[0026] The controller 22 may be a personal computer, a tablet computer, or the like. The controller 22 may realize each function by executing a program. An operation device (not shown) for a 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 unit 20, a switch, a keyboard, or the like.

[0027] The transducer control unit 18 may be configured by a processor that executes a program to control each ultrasonic transducer 32. The transducer control unit 18 causes each ultrasonic transducer 32 to generate ultrasonic waves in response to the control of the controller 22. The transducer control unit 18 also adjusts at least one of the intensity and delay time of the ultrasonic waves generated by each ultrasonic transducer 32 in response to the control of the controller 22.

[0028] The ultrasonic probe 12 extending in the vertical direction is attached to the transducer housing 26 so that ultrasonic waves are transmitted and received at a position below the transducer housing 26 and above the treatment reference point P. In this embodiment, the ultrasonic probe 12 penetrates the apex of the concave surface 30 of the transducer housing 26 in the vertical direction, and a transmitting / receiving unit 28 that transmits and receives ultrasonic waves faces downward.

[0029] A coupling bag 24 is provided below the HIFU transducer unit 10 to match acoustic impedance between each ultrasonic transducer 32 and the patient, and between the ultrasonic probe 12 and the patient. The coupling bag 24 may be a bag filled with a liquid such as water. The ultrasonic probe 12 penetrates the coupling bag 24 from above to the inside, and the transmitting / receiving unit 28 is located inside the coupling bag 24.

[0030] An ultrasonic diagnostic device may be used as the data acquisition unit 16. The data acquisition unit 16 executes the following process according to the control of the controller 22. That is, the data acquisition unit 16 causes the ultrasonic probe 12 to transmit ultrasonic waves and causes scanning with a beam of the transmitted ultrasonic waves (ultrasonic beam).

[0031] The transmitting / receiving unit 28 of the ultrasonic probe 12 has a long axis direction and a short axis direction, and an ultrasonic beam is scanned on an observation surface 44 that spreads in the long axis direction and in a direction away from the transmitting / receiving unit 28. The ultrasonic probe 12 is attached to the HIFU transducer unit 10 so that the observation surface 44 includes a central axis 40 that passes through the apex of the concave surface 30 of the transducer housing 26 from top to bottom.

[0032] The data acquisition unit 16 causes the ultrasonic probe 12 to receive reflected ultrasonic waves arriving from the direction in which the ultrasonic beam is directed, and acquires reception signals based on the reflected ultrasonic waves received from each direction in which the ultrasonic beam is directed. The data acquisition unit 16 generates ultrasonic data based on the reception signals obtained at the observation plane 44, and outputs the data to the controller 22. The ultrasonic data may be, for example, data indicating a B-mode image (tomographic image) acquired for the observation plane 44.

[0033] The ultrasonic probe 12 is freely rotatable around a central axis 40 by a probe driver 14. The probe driver 14 rotates the ultrasonic probe 12 around the central axis 40 relative to the HIFU transducer unit 10. That is, the probe driver 14 rotates the ultrasonic probe 12 around the central axis 40 and rotates an observation surface 44 of the ultrasonic probe 12 around the central axis 40 in response to the control of the controller 22.

[0034] During treatment, the coupling bag 24, the ultrasonic probe 12, and the HIFU transducer unit 10 are positioned so that the lower part of the coupling bag 24 is in close contact with the patient. Before the therapeutic ultrasonic waves are irradiated from the HIFU transducer unit 10 to the patient, the following positioning process is performed.

[0035] The transducer control unit 18 causes each ultrasonic transducer 32 included in the HIFU transducer unit 10 to transmit ultrasonic waves having a lower intensity than that during treatment. The probe driving unit 14 sets the rotation angle position (position represented by a rotation angle) of the ultrasonic probe 12 so that the ultrasonic beam scans an observation plane 44 expanding in a predetermined direction.

[0036] The data acquisition unit 16 causes the ultrasonic probe 12 to scan an ultrasonic beam on an observation plane 44 defined by the rotation angle position of the ultrasonic probe 12, acquires ultrasonic data, and outputs the data to the controller 22. The controller 22 causes the display unit 20 to display a B-mode image indicated by the ultrasonic data and an image indicating the treatment reference point P in a superimposed manner. The user as a practitioner refers to the image displayed on the display unit 20 to confirm the difference between the position (focus F) where the ultrasonic waves transmitted from the HIFU transducer unit 10 are intensified and the position of the treatment reference point P.

[0037] When the difference between the position of the focal point F and the position of the treatment reference point P is not within the allowable range, the user changes the position or posture of the coupling bag 24, the ultrasonic probe 12, and the HIFU transducer unit 10. Alternatively, the user changes the contact state between the coupling bag 24 and the patient 34. After the user confirms that the position of the focal point F and the position of the treatment reference point P match, or that the difference between the position of the focal point F and the position of the treatment reference point P is within the allowable range, the user performs an operation for treatment on the controller 22. The controller 22 controls the transducer control unit 18 in response to the operation by the user. The transducer control unit 18 causes each ultrasonic transducer 32 to transmit therapeutic ultrasonic waves having an intensity required for treatment in response to the control by the controller 22. As a result, the living tissue at the focal point F is cauterized, and treatment is performed.

[0038] In treatment using high-intensity focused ultrasound, if there is an area in the patient's tissue that has acoustic characteristics different from the surroundings, the position of the focal point F may shift from the case where the acoustic characteristics are uniform due to refraction of the ultrasound emitted from the ultrasound transducer 32. This may cause the ultrasound focal point F to not appear on the B-mode image, making the positioning process difficult.

[0039] Therefore, in the HIFU irradiation apparatus 100 according to this embodiment, a focus adjustment process described below may be performed before the positioning process is performed. By the focus adjustment process, the focus F moves onto the observation plane 44 of the ultrasonic probe 12. Furthermore, the focus F may be moved closer to the central axis 40 or set on the central axis 40.

[0040] The controller 22 controls the data acquisition unit 16 to cause the data acquisition unit 16 to acquire B-mode image data as ultrasound data. The data acquisition unit 16 causes the ultrasound probe 12 to transmit ultrasound and scan the observation plane 44 with the ultrasound beam. The data acquisition unit 16 causes the ultrasound probe 12 to receive reflected ultrasound arriving from the direction in which the ultrasound beam is directed, and acquires reception signals based on the reflected ultrasound received from each direction in which the ultrasound beam is directed. The data acquisition unit 16 generates ultrasound data based on the reception signals obtained at the observation plane 44, and outputs the data to the controller 22.

[0041] Moreover, the controller 22 controls the transducer control section 18 to cause each of the ultrasonic transducers 32 included in the HIFU transducer unit 10 to transmit ultrasonic waves having an intensity lower than that during treatment.

[0042] Figures 2 to 4 are diagrams for explaining the focus adjustment process. The left side of Figure 2 shows a state in which the minor axis direction of the transmitting / receiving unit 28 is oriented left and right. The right side of Figure 2 shows a state in which the major axis direction of the transmitting / receiving unit 28 is oriented left and right. Figure 3 shows a state in which the major axis direction of the transmitting / receiving unit 28 is oriented left and right, and Figure 4 shows a state in which the minor axis direction of the transmitting / receiving unit 28 is oriented left and right.

[0043] The left side of FIG. 2 shows a state where the focal point F is located at a position away from the observation surface 44. However, in this figure, for clarity, the notation of the coupling bag 24 is omitted. The notation of the coupling bag 24 is also omitted in FIG. 3 and FIG. 4 described later. The controller 22 controls the probe driving unit 14 to search for the focal point F on the B-mode image shown by the ultrasound data output from the data acquisition unit 16 while rotating the ultrasound probe 12 about the central axis 40. The probe driving unit 14 rotates the ultrasound probe 12 around the central axis 40 within a range of at least 90°. The controller 22 controls the probe driving unit 14 to stop the ultrasound probe 12 at the rotation angle position when the focal point F is detected on the B-mode image. The right side of FIG. 2 and the left side of FIG. 3 show the ultrasound beam scanning area 42 and the focal point F when the focal point F is detected on the B-mode image. Here, the ultrasound beam scanning area 42 is an area where the ultrasound beam is scanned, and B-mode image data is generated for this area.

[0044] The controller 22 controls the transducer control unit 18 to adjust the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32, and move the focal point F within the observation plane 44. That is, the transducer control unit 18 adjusts the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32 in accordance with the control of the controller 22, moves the focal point F within the observation plane 44, and moves the focal point F closer to the central axis 40 or positions the focal point F on the central axis 40. The right side of FIG. 3 shows a schematic diagram of the ultrasonic beam scanning region 42 and the focal point F when the focal point F is positioned on the central axis 40.

[0045] In the HIFU irradiation apparatus 100, as shown in the left side of FIG. 3, even if the focus F is not located on the central axis 40, the positioning process may be performed with the focus F on the B-mode image, or as shown in the right side of FIG. 3, the positioning process may be performed with the focus F located on the central axis 40.

[0046] The focus adjustment process may be performed by adjusting the delay time of the ultrasonic waves emitted from each of the multiple ultrasonic transducers 32 without rotating the ultrasonic probe 12. The left side of FIG. 4 shows a state where the focal point F is located at a position away from the observation surface 44. The controller 22 controls the transducer control unit 18 to adjust the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32, and move the focal point F within a plane intersecting the observation surface 44, for example, within a plane perpendicular to the observation surface 44. That is, the transducer control unit 18 adjusts the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32 according to the control of the controller 22, moves the focal point F within the plane intersecting the observation surface 44, and positions the focal point F on the observation surface 44. The right side of FIG. 4 shows the ultrasonic beam scanning area 42 and the focal point F when the focal point F is positioned on the observation surface 44.

[0047] The state shown on the right side of Fig. 4 is the same as the state shown on the left side of Fig. 3. The controller 22 controls the transducer control unit 18 to adjust the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32, and move the focal point F within the observation plane 44. That is, the transducer control unit 18 adjusts the delay time of the ultrasonic waves generated by each of the multiple ultrasonic transducers 32 according to the control of the controller 22, moves the focal point F within the observation plane 44, and moves the focal point F closer to the central axis 40 or positions the focal point F on the central axis 40. The right side of Fig. 3 shows a schematic view of the ultrasonic beam scanning area 42 and the focal point F when the focal point F is positioned on the central axis 40.

[0048] Even when the ultrasonic probe 12 is not rotated, in the HIFU irradiation device 100, even if the focal point F is not located on the central axis 40, the positioning process may be performed in a state where the focal point F is located on the B-mode image as shown on the left side of Fig. 3. Also, the positioning process may be performed in a state where the focal point F is located on the central axis 40 as shown on the right side of Fig. 3.

[0049] In this manner, in the HIFU irradiation apparatus 100, the focus adjustment process is performed by a focus adjustment method including the following steps (i) to (iii). (i) a step of searching for a focal point F of the ultrasound emitted from the plurality of ultrasound transducers 32 on a B-mode image shown by the B-mode image data while changing a rotation angle position of the ultrasound probe 12 around the central axis 40 while transmitting ultrasound from the plurality of ultrasound transducers 32; (ii) stopping the ultrasonic probe 12 at the rotation angle position when the focal point F is detected; (iii) A step of adjusting the delay time of each ultrasonic wave emitted from the plurality of ultrasonic transducers 32 while keeping the ultrasonic probe 12 stationary at the rotation angle position when the focal point F is detected, to bring the focal point closer to the central axis 40 or to position the focal point F on the central axis 40.

[0050] In the focus adjustment method, the above step (iii) does not necessarily have to be performed. The focus adjustment method may be one in which the above steps (i) and (ii) are performed.

[0051] Moreover, in the HIFU irradiation apparatus 100, the focus adjustment process may be performed by a focus adjustment method including the following steps (a) and (b). (a) a step of searching for a focal point F of the ultrasound emitted from the plurality of ultrasound transducers 32 on a B-mode image shown by the B-mode image data while adjusting a delay time of the ultrasound emitted from each of the plurality of ultrasound transducers 32 while transmitting ultrasound from the plurality of ultrasound transducers 32; (b) A step of adjusting the delay time of the ultrasonic waves emitted from each of the plurality of ultrasonic transducers 32 from a state in which the ultrasonic waves are generated from each of the plurality of ultrasonic transducers 32 at the delay time when the focal point F is detected, thereby bringing the focal point closer to the central axis 40 or positioning the focal point F on the central axis 40.

[0052] In the focus adjustment method, the step (b) above does not necessarily have to be performed. The focus adjustment method may be one in which the step (a) above is performed.

[0053] 5 shows the configuration of a HIFU irradiation device 102 according to the second embodiment of the present invention. The HIFU irradiation device 102 is obtained by adding a transducer unit driving section 90 to the HIFU irradiation device 100. The transducer unit driving section 90 rotates the HIFU transducer unit 10 around the central axis 40 with respect to a reference coordinate system fixed to a bed or the like on which a patient 34 lies, under the control of the controller 22. That is, the transducer unit driving section 90 has a function as an ultrasonic transducer driving section that rotates a plurality of ultrasonic transducers 32 arranged along the concave surface 30 around the central axis 40.

[0054] In this embodiment, the probe driver 14 maintains the ultrasonic probe 12 in a stationary state. Here, the state in which the ultrasonic probe 12 is stationary refers to a state in which the ultrasonic probe 12 is stationary in the reference coordinate system. The transducer unit driver 90 rotates the HIFU transducer unit 10 in a rotation direction opposite to the rotation direction of the ultrasonic probe 12 in the focus adjustment process described with reference to Figs. 2 to 4 for the first embodiment.

[0055] The probe driver 14 rotates the ultrasonic probe 12 around the central axis 40 relative to the HIFU transducer unit 10. Therefore, by setting the rotation angle of the ultrasonic probe 12 relative to the HIFU transducer unit 10 to the same angle in the opposite direction as the rotation angle in the reference coordinate system of the HIFU transducer unit 10, the ultrasonic probe 12 is brought into a stationary state in the reference coordinate system. This allows the position of the focal point F on the B-mode image to be adjusted without changing the B-mode image displayed on the display unit 20.

[0056] In the HIFU irradiation device 102, the focus adjustment process is performed by a focus adjustment method including the following steps (α) to (γ). (α) A step of searching for a focal point F of the ultrasound emitted from the plurality of ultrasound transducers 32 on a B-mode image shown by the B-mode image data while changing the rotation angle position of the HIFU transducer unit 10 around the central axis 40, i.e., the rotation angle positions of the plurality of ultrasound transducers 32, while transmitting ultrasound from the plurality of ultrasound transducers 32. (β) Step of stopping the HIFU transducer unit 10 at the rotation angle position when the focal point F is detected (γ) A step of adjusting the delay time of each ultrasonic wave emitted from the plurality of ultrasonic transducers 32 while keeping the HIFU transducer unit 10 stationary at the rotation angle position when the focal point F is detected, to bring the focal point closer to the central axis 40 or to position the focal point F on the central axis 40.

[0057] In the focus adjustment method, the above step (γ) does not necessarily have to be performed. The focus adjustment method may be one in which the above steps (α) and (β) are performed.

[0058] According to the focus adjustment process described above, the focus F can be positioned on the observation surface 44. Therefore, even if the focus F does not appear in the B-mode image due to refraction, the positioning process can be performed by positioning the focus F on the observation surface 44. Furthermore, in the focus adjustment process, the focus F may be brought closer to the central axis 40, or the focus F may be set on the central axis 40. In this case, the focus F is located below the ultrasound probe 12, and the image of the focus F is located at a position where it is easy to see in the B-mode image. This makes it easier to perform the positioning process. [Explanation of symbols]

[0059] 10 HIFU transducer unit, 12 ultrasonic probe, 14 probe drive unit, 16 data acquisition unit, 18 transducer control unit, 20 display unit, 22 controller, 24 coupling bag, 26 transducer housing, 28 transceiver unit, 30 concave surface, 32 ultrasonic transducer, 40 central axis, 42 ultrasonic beam scanning area, 44 observation surface, 90 transducer unit drive unit, 100, 102 HIFU irradiation device.

Claims

1. A transducer control unit that controls a plurality of ultrasonic transducers arranged along the concave surface; a probe driving unit that rotates an ultrasonic probe disposed on a central axis of the concave surface around the central axis; a data acquisition unit that acquires B-mode image data by the ultrasonic probe; a controller for controlling the transducer control unit, the probe driving unit, and the data acquisition unit; The controller: a process of searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image represented by the B-mode image data while changing a rotation angle position of the ultrasonic probe around the central axis while transmitting ultrasonic waves from the plurality of ultrasonic transducers; and performing a process of stopping the ultrasonic probe at the rotation angle position when the focus is detected.

2. 2. The HIFU irradiation device according to claim 1, The controller: A HIFU irradiation device characterized by adjusting the delay time of ultrasonic waves emitted from each of the multiple ultrasonic transducers while keeping the ultrasonic probe stationary at the rotation angle position when the focus is detected, to bring the focus closer to the central axis or to position the focus on the central axis.

3. A transducer control unit that controls a plurality of ultrasonic transducers arranged along the concave surface; an ultrasonic transducer driving unit that rotates the ultrasonic transducers around a central axis of the concave surface; a data acquisition unit that acquires B-mode image data using an ultrasonic probe disposed on a central axis of the concave surface; A controller that controls the transducer control unit, the ultrasonic transducer driving unit, and the data acquisition unit, The controller: a process of searching for focal points of ultrasound emitted from the plurality of ultrasound transducers on a B-mode image represented by the B-mode image data while changing rotation angle positions of the plurality of ultrasound transducers around the central axis while transmitting ultrasound from the plurality of ultrasound transducers; and performing a process of stopping the plurality of ultrasonic transducers at the rotation angle position when the focus is detected.

4. 4. The HIFU irradiation device according to claim 3, The controller: A HIFU irradiation device characterized in that, while the plurality of ultrasonic transducers are kept stationary at the rotation angle position when the focus is detected, the delay time of the ultrasonic waves emitted from each of the plurality of ultrasonic transducers is adjusted to bring the focus closer to the central axis or to position the focus on the central axis.

5. A transducer control unit that controls a plurality of ultrasonic transducers arranged along the concave surface; a data acquisition unit that acquires B-mode image data using an ultrasonic probe disposed on a central axis of the concave surface; a controller for controlling the transducer control unit and the data acquisition unit; The controller: A HIFU irradiation device characterized in that, when transmitting ultrasound from the plurality of ultrasound transducers, a process is executed to search for a focus of the ultrasound emitted from the plurality of ultrasound transducers on a B-mode image represented by the B-mode image data while adjusting a delay time of the ultrasound emitted from each of the plurality of ultrasound transducers.

6. 6. The HIFU irradiation device according to claim 5, A HIFU irradiation device characterized in that, from a state in which ultrasonic waves are generated from each of the plurality of ultrasonic transducers at the delay time when the focus is detected, the delay time of the ultrasonic waves emitted from each of the plurality of ultrasonic transducers is further adjusted to bring the focus closer to the central axis or to position the focus on the central axis.

7. A plurality of ultrasonic transducers arranged along the concave surface; an ultrasonic probe disposed on a central axis of the concave surface and rotatably around the central axis; A focus adjustment method for a HIFU irradiator comprising: a data acquisition unit that acquires B-mode image data by the ultrasonic probe, a step of searching for focal points of ultrasonic waves emitted from the plurality of ultrasonic transducers on a B-mode image represented by the B-mode image data while changing a rotation angle position of the ultrasonic probe around the central axis while transmitting ultrasonic waves from the plurality of ultrasonic transducers; and stopping the ultrasonic probe at the rotational angle position when the focus was detected.

8. 8. The focus adjustment method according to claim 7, A focus adjustment method comprising the steps of: adjusting a delay time of each ultrasonic wave emitted from a plurality of ultrasonic transducers while keeping the ultrasonic probe stationary at the rotation angle position when the focus is detected, thereby moving the focus closer to the central axis or positioning the focus on the central axis.

9. A plurality of ultrasonic transducers arranged along the concave surface, the plurality of ultrasonic transducers being rotatably arranged around a central axis of the concave surface; an ultrasonic probe disposed on a central axis of the concave surface; A focus adjustment method for a HIFU irradiator comprising: a data acquisition unit that acquires B-mode image data by the ultrasonic probe, a step of searching for focal points of ultrasound emitted from the plurality of ultrasound transducers on a B-mode image represented by the B-mode image data while changing rotation angle positions of the plurality of ultrasound transducers around the central axis while transmitting ultrasound from the plurality of ultrasound transducers; and stopping the plurality of ultrasonic transducers at the rotational angle position when the focus is detected.

10. 10. The focus adjustment method according to claim 9, further comprising the steps of: A focus adjustment method comprising the steps of: adjusting a delay time of each ultrasonic wave emitted from the plurality of ultrasonic transducers while keeping the plurality of ultrasonic transducers stationary at the rotational angle position when the focus is detected, thereby moving the focus closer to the central axis or positioning the focus on the central axis.

11. A plurality of ultrasonic transducers arranged along the concave surface; A data acquisition unit that acquires B-mode image data by an ultrasonic probe disposed on a central axis of the concave surface, A focus adjustment method comprising the steps of: searching for a focus of ultrasound emitted from the plurality of ultrasound transducers on a B-mode image represented by the B-mode image data while adjusting a delay time of the ultrasound emitted from each of the plurality of ultrasound transducers while transmitting ultrasound from the plurality of ultrasound transducers.

12. The focus adjustment method according to claim 11, A focus adjustment method characterized by including a step of: generating ultrasonic waves from each of the plurality of ultrasonic transducers at the delay time when the focus is detected; and then adjusting the delay time of the ultrasonic waves emitted from each of the plurality of ultrasonic transducers to bring the focus closer to the central axis or to position the focus on the central axis.

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