JP2015217247A5 - - Google Patents

Description

Ultrasonic therapy apparatus and ultrasonic therapy system

  The present invention relates to an ultrasound treatment apparatus and an ultrasound treatment system, and relates to an ultrasound treatment apparatus and an ultrasound treatment apparatus for treating a target site set in a living body using high intensity focused ultrasound (HIFU). The present invention relates to a sonic therapy system.

  HIFU treatment is known as a less invasive treatment that uses locally focused ultrasound to locally heat a focused biological tissue that is set at the treatment site and cauterize the tissue at that site. Yes. For example, it has been proposed to insert a treatment probe into the rectum of a living body and irradiate HIFU to the lesioned part at the site to be treated. In addition, an ultrasonic treatment apparatus using HIFU introduced in Patent Document 1 has proposed a treatment probe for driving a plurality of treatment transducers (transducers) with ultrasonic electric signals supplied from a multichannel generator. ing. According to this, HIFU can be focused on a wide range of treatment target parts by independently controlling the amplitude, frequency, and phase of the ultrasonic electric signal supplied to each treatment transducer.

Japanese Patent No. 4519905 JP 2011-115461 A

Palmeri ML, Wang MH, Dahl JJ, Frinkley KD, et al. Quantifying hepatic shear modulus in vivo using acoustic radiation force.Ultrasound inMedicine & Biology 2008; 34: 546-58.

  However, since high intensity treatment ultrasonic waves are periodically emitted from each treatment vibrator, there is a possibility that the skin on the surface of the living body on the treatment ultrasonic beam may be burned. That is, in normal HIFU treatment, a high-intensity ultrasonic wave called a trigger pulse and an ultrasonic wave called a heating pulse whose intensity is lower than the trigger pulse are repeatedly irradiated. When there is a boundary between propagation media (for example, skin and water) having extremely different impedances on such a therapeutic ultrasonic beam, bubbles due to a cavitation phenomenon are generated at the interface by the trigger pulse. Subsequently, when the heating pulse is irradiated, the bubbles are broken and heat is generated, and if the treatment ultrasonic beam is strong, there is a possibility that the skin becomes hot due to high temperature. When such a skin burn occurs, not only the lesion in the deep part of the living body cannot be treated, but also damage to normal tissue becomes a problem.

Therefore, since the intensity of the therapeutic ultrasonic beam emitted from each treatment transducer is limited, a treatment probe in which a plurality of treatment transducers are arranged in a hemispherical concave surface has been proposed.
According to this, even if the intensity | strength of the therapeutic ultrasound beam inject | emitted from each treatment vibrator | oscillator is restrict | limited, the therapeutic ultrasound energy required for a treatment can be focused on a treatment object site | part.

  On the other hand, it is known that the incident angle of the therapeutic ultrasound beam on the body surface (skin) of the living body affects the therapeutic effect, and the ideal incident angle of the therapeutic ultrasound beam is perpendicular to the body surface (90 °). In other words, when the treatment ultrasound beam is incident on the body surface perpendicularly, there is little loss of reflection or absorption of the treatment ultrasound on the skin, and the treatment ultrasound enters the living body and energy to the focal point set in the treatment target site. Highest transmission efficiency.

  By the way, when the treatment transducers of the treatment probe are distributed on the concave surface of the hemisphere, the treatment ultrasonic beam is incident on the body surface according to the position of the treatment transducer on the concave surface or the shape of the body surface. The angle is different. However, as the incident angle with respect to the body surface moves away from the vertical, the rate at which the therapeutic ultrasound beam emitted from the treatment transducer is reflected or absorbed by the body surface increases, and the energy transfer efficiency to the inside of the living body and the focal point decreases. To do. As a result, there is a problem that the total amount of HIFU energy irradiated to the treatment target site is reduced and the treatment effect is lowered.

  The problem to be solved by the present invention is to maintain the total amount of HIFU energy irradiated to the treatment target site at the target value even if the incident angle of the treatment ultrasonic beam of each treatment transducer with respect to the body surface is different, An object of the present invention is to provide an ultrasonic treatment apparatus and an ultrasonic treatment system capable of obtaining a desired therapeutic effect.

  In order to solve the above-described problems, the ultrasonic treatment apparatus of the present invention is a treatment that irradiates a therapeutic ultrasonic wave to a focal point set in a treatment target site of a living body from a plurality of treatment vibrators arranged on a hemispherical concave surface A probe, a treatment transducer control unit for controlling the intensity of the treatment ultrasound beam emitted from each treatment transducer, and a central portion of the concave surface of the treatment probe for imaging between the living body and the living body An imaging probe having a plurality of imaging transducers for transmitting and receiving the ultrasound, an ultrasound image forming unit for generating an ultrasound image including the focal point generated from a reception signal of the imaging probe, and the ultrasound A display unit that displays an image, and the treatment transducer control unit, based on the ultrasound image displayed on the display unit, of the treatment ultrasound beam irradiated to the focal point from each treatment transducer Body surface of the living body Angle of incidence is calculated, and for compensating the intensity of the therapeutic ultrasound beams the decrease in accordance with the calculated the incident angle is emitted from each treatment resonator for.

  According to the ultrasonic treatment apparatus of the present invention, each treatment transducer that calculates an incident angle with respect to the body surface of a living body for each treatment ultrasonic beam emitted from a plurality of treatment transducers and decreases according to the calculated incidence angle. Compensates for a decrease in the intensity of the therapeutic ultrasound beam applied to the focal point. Thereby, even if the treatment ultrasound is reflected or absorbed by the body surface and decreases according to the incident angle of the treatment ultrasound beam with respect to the body surface, the intensity of the treatment ultrasound beam irradiated to the focal point from each treatment vibrator is reduced. Compensated. As a result, the HIFU energy irradiated to the treatment target site from the entire treatment probe can be maintained at the target value, and desired treatment accuracy and treatment effect can be stably obtained.

  In addition, according to the present invention, since the incident angle of the therapeutic ultrasonic beam on the body surface is calculated, it is possible to warn the operator of the incident angle of each therapeutic transducer with image information, sound, or the like. Thereby, the surgeon can avoid irradiation of therapeutic ultrasonic waves exceeding the allowable incident angle range. Specifically, based on the warning, the operator changes or maintains the position and angle of the treatment probe (in this specification, collectively referred to as “position”), thereby maintaining the energy transfer efficiency above a certain level. A therapeutic effect that ensures a high degree of treatment accuracy can be obtained. In addition, side effects such as skin burns can be suppressed. If the surgeon changes the position of the treatment probe based on the warning, the incident angle of the treatment ultrasound beam of each treatment transducer at the changed position with respect to the body surface of the living body is calculated, and the treatment ultrasound beam Needless to say, the process of compensating the intensity is repeated.

  According to the present invention, the total amount of HIFU energy irradiated to the treatment target region is maintained at the target value even when the incident angles of the treatment ultrasonic beams of the individual treatment transducers on the body surface are different, and a desired treatment effect is achieved. Can be obtained.

1 is a diagram illustrating an overall configuration of an ultrasonic therapy system according to an embodiment of the present invention. It is a block block diagram of the ultrasonic therapy apparatus of one Embodiment of this invention. It is a figure explaining the structure of the ultrasonic treatment probe of one Embodiment of this invention. It is a figure explaining focused ultrasound treatment. It is a figure explaining the navigation guide display function of the ultrasonic treatment system of one embodiment of the present invention. It is a flowchart which shows the process sequence of the ultrasonic treatment system of one Embodiment of this invention. FIG. 7 is a detailed flowchart of a portion related to a characteristic part of an embodiment of the present invention shown in the flowchart of FIG. It is a figure which shows arrangement | positioning of the treatment ultrasonic beam inject | emitted from the some treatment vibrator | oscillator of the treatment probe of one Embodiment of this invention, and a some treatment vibrator | oscillator. It is a figure explaining the pulse pattern of HIFU. It is a figure explaining the method of compensating the intensity | strength of a therapeutic ultrasonic beam according to an incident angle while describing the calculation method of the incident angle which the therapeutic ultrasonic beam which concerns on the characteristic of this invention injects into a body surface. 4 is a data table showing the treatment transducers (channels) calculated according to the present invention, the incidence angle of the treatment ultrasonic beam with respect to the body surface, and the intensity of the treatment ultrasonic beam to be compensated according to the incidence angle. It is a figure which shows the example of a display of GUI at the time of the surgery or treatment of one Embodiment of this invention.

  Hereinafter, the present invention will be described based on embodiments.

  FIG. 1 shows the overall configuration of the ultrasonic therapy system of the present invention. A magnetic resonance imaging (MRI) apparatus 1 which is one of medical imaging apparatuses is, for example, a perpendicular magnetic field permanent magnet type MRI apparatus. However, the present invention is not limited to the MRI apparatus, and a known medical image apparatus such as a CT apparatus, a PET apparatus, an ultrasonic image apparatus, or the like can be applied.

As illustrated, the MRI apparatus 1 includes an upper magnet 3 and a lower magnet 5 that generate a vertical static magnetic field, a support 7 that connects the magnets and supports the upper magnet 3, a position detection device 9, an arm 11, and a monitor 13. 14, a monitor support unit 15, a reference tool 17, a personal computer 19, a bed 21, an MRI control unit 23, and the like. A gradient magnetic field generator (not shown) of the MRI apparatus 1 generates a gradient magnetic field. The MRI apparatus 1 further includes an RF transmitter (not shown ) for generating nuclear magnetic resonance in a living body (patient 24) in a static magnetic field, and an RF receiver (not shown) for receiving a nuclear magnetic resonance signal from the patient 24. Yes.

  The position detection device 9 is a three-dimensional position detector that detects a three-dimensional position and posture of the ultrasonic therapy probe 37 (hereinafter collectively referred to as a position). That is, the position detection device 9 includes two infrared cameras 25 and a light emitting diode (not shown) that emits infrared light, and detects the three-dimensional position of the pointer 27 attached to the ultrasonic therapy probe 37. Thereby, the pointer 27 functions as an instruction device for the imaging tomographic plane of the ultrasonic image and the MR image, together with the function of detecting the position of the ultrasonic therapy probe 37. Further, the position detection device 9 is connected to the upper magnet 3 so as to be movable by the arm 11, and is formed so that the arrangement with respect to the MRI apparatus 1 can be appropriately changed. On the monitor 13, an ultrasonic image of the tomographic plane of the patient 24 indicated by the pointer 27 held by the operator 29 is displayed. The monitor 13 is connected to the upper magnet 3 by the monitor support portion 15 in the same manner as the infrared camera 25. The reference tool 17 links the coordinate system of the infrared camera 25 and the coordinate system of the MRI apparatus 1, includes three reflection spheres 35, and is provided on the side surface of the upper magnet 3.

  Information of the pointer 27 detected and calculated by the infrared camera 25 is transmitted to the personal computer 19 as position data of the ultrasonic treatment probe 37, for example, via the RS232C cable 33. The MRI control unit 23 is composed of a workstation and controls an RF transmitter, an RF receiver, etc. (not shown). Further, the MRI control unit 23 is connected to the personal computer 19. In the personal computer 19, the position data of the pointer 27 detected and calculated by the infrared camera 25 is converted into position data of the imaging range in the MRI apparatus 1 and transmitted to the MRI control unit 23. The position data is reflected in the control of the imaging section of the imaging sequence. The MR image acquired with the new imaging section is displayed on the monitor 13. MR images are simultaneously recorded in the video recording device 34.

The ultrasonic therapy apparatus 40 projects an ultrasonic image obtained by the ultrasonic therapy probe 37 to which the pointer 27 is attached on a dedicated monitor 38. The ultrasonic image is an image processing is performed are transferred to the personal computer 19, displayed on the monitor 13. The ultrasonic therapy probe 37 is formed of a non-magnetic material such as ceramic that can be operated even in the magnetic field of the MRI apparatus 1. The ultrasonic therapy probe 37 may be selectively used as 2 MHz or 1 MHz as necessary.

FIG. 2 shows a block configuration of the main part of the ultrasonic therapy apparatus 40. The ultrasonic treatment apparatus 40 is configured to include an ultrasonic treatment probe 37 that treats a patient 24 by irradiating therapeutic ultrasound, and irradiates the patient 24 with HIFU (high-density focused ultrasound) to perform ultrasonic treatment. Is what you do. In addition, the ultrasonic treatment device 40 uses a reflected echo signal obtained by transmitting and receiving ultrasonic waves from the ultrasonic treatment probe 37 into the patient 24, and uses a two-dimensional ultrasonic image or a three-dimensional ultrasonic image including a treatment target region. Is displayed on the monitor 38. That is, as will be described later, the ultrasound treatment probe 37 includes a treatment probe 37a (FIG. 3) for irradiating HIFU treatment ultrasound and an imaging probe 37b (FIG. 3) for imaging an ultrasound image. In addition, the ultrasonic therapy apparatus 40 includes an ultrasonic transmission / reception unit 44 that transmits and receives an ultrasonic signal to the imaging probe 37b, and a two-dimensional ultrasonic image (for example, a B-mode image) including a HIFU focus based on the received signal or a tertiary Ultrasound image constructing unit 45 constituting the original ultrasound image, monitor 38 displaying the ultrasound image composed of the ultrasound image constructing unit 45, treatment probe 37a and imaging probe 37b for irradiating the patient 24 HIFU controller 49 for switching the ultrasonic intensity to be supplied to, ultrasonic control unit 47 for controlling each component, and control panel 48 for giving instructions to ultrasonic control unit 47.

The HIFU controller 49 drives the imaging probe 37b when operating the ultrasound therapy apparatus 40 as an ultrasound imaging apparatus to irradiate the patient 24 with weak ultrasound for imaging, and when operating as the therapy apparatus, the therapy probe 37a The patient 24 is irradiated with intense ultrasonic waves for treatment. In this example, the ultrasonic diagnostic apparatus is incorporated in the ultrasonic therapeutic apparatus 40, but the ultrasonic diagnostic apparatus and the ultrasonic therapeutic apparatus may be configured as separate apparatuses. The HIFU controller 49 is a treatment transducer controller that controls the treatment transducer 39 (FIG. 3) of the treatment probe 37a, and controls the intensity of the treatment ultrasonic beam emitted from each treatment transducer. It has become.

FIG. 3 shows a configuration diagram of an embodiment of the ultrasonic therapy probe 37 according to the feature of the present invention.
FIG. 4A is a cross-sectional view of a plane passing through the central axis of the ultrasonic treatment probe 37, and FIG. 4B is a front view of the ultrasonic treatment probe 37 viewed from the ultrasonic emission surface side. As is apparent from the figure, the ultrasonic treatment probe 37 includes a treatment probe 37a formed on a hemispherical concave surface and an imaging probe 37b for imaging an ultrasonic image disposed on the central axis of the concave surface. Is formed. The imaging probe 37b can capture a tomographic image (ultrasonic image) of the fan-shaped region 601 shown in the figure.

As shown in FIG. 4 (b), the treatment probe 37a divides the concave surface into a plurality of concentric annular regions and further divides the annular region into a plurality of regions in the radial direction. 39 is provided. In other words, the treatment probe 37a is configured as a two-dimensional matrix array transducer in which a plurality of treatment transducers 39 are arranged. Here, the number of divisions of the plurality of treatment transducers 39 is 40 in the illustrated example for simplification, but the number of divisions is generally 2 ⁿ , for example, 512 or 1024 Things are used. The imaging probe 37b is an imaging ultrasonic probe for imaging and drawing the tomographic plane 601 including the focus of the treatment target region.

An outline of performing treatment by irradiating high-intensity focused ultrasound (HIFU) with the thus configured ultrasound treatment apparatus 40 will be described with reference to FIG. As shown in FIG. 4 (a), the HIFU 404, which is a bundle of therapeutic ultrasound beams 404a emitted from the respective treatment transducers 39 of the treatment probe 37a, is irradiated so as to be focused on a focal point 403. Further, as shown in FIG. 4 (b), the range treated (cauterized) by one HIFU irradiation is, for example, a diameter Φ of 5 to 10 mm. Therefore, when performing treatment with HIFU irradiation, as shown in FIG. 4 (c), the position of the focal point 403, which is the irradiation position of HIFU404, is sequentially moved to irradiate the entire treatment target region (target) 402 with HIFU404. To do. At that time, the state of treatment is monitored by an ultrasonic image picked up by the image pickup probe 37b attached to the center of the ultrasonic treatment probe 37. However, if treatment and monitoring are performed simultaneously, they will appear in the image as noise. Therefore, a clear diagnostic image free from noise is acquired by operating the treatment probe 37a and the imaging probe 37b alternately. Note that by performing focus visualization with ARFI (Acoustic Radiation Force Impulse) as shown in Non- Patent Document 1, the actual affected area in the living tissue is calculated for the ideal cautery area, and three-dimensional measurement is performed. Thus, a three-dimensional treatment planned area can be calculated.

In the following, with reference to FIG. 5, illustrating a navigation guide display function of the present embodiment. The operator 29 adjusts the focus 403 of the treatment probe 37a connected to the ultrasonic therapy apparatus 40 with respect to the patient 24 to one point of the treatment target site (target). That is, the position of the ultrasonic treatment probe 37 is detected from the position of the pointer 27 by the infrared camera 25 attached to the position detection device 9, and the simulated images of the focal point 403 and the HIFU 404 of the treatment probe 37a are displayed on the navigation screens 531 to 534. Each is displayed. The surgeon 29 operates the position of the ultrasonic therapy probe 37 while viewing the navigation screens 531 to 534 to adjust the focus 403 of the therapy probe 37a to the target. As the navigation screen configuration, for example, a three-dimensional volume rendering image 534 or the like can be used in addition to the three-axis cross sections (Axial, Sagittal, Coronal) 531 to 533, but can be freely customized. In addition, the operator 29 previously sets a treatment planned area 536 that is a treatment target site, a warning area, a margin, and the like in advance.

  In addition to the simulated image of the ultrasonic therapy probe 37, preoperative planning (surgical simulation) information 537 can be superimposed on the navigation image. In the case of a volume rendering image 534 or the like, the treatment scheduled area 536 can be displayed in a three-dimensional manner. Further, it is possible to provide a function of issuing a warning when entering the treatment scheduled area 536 or the warning area on the navigation images 531 to 534. In addition, for example, when the treatment scheduled area 536 enters the warning area, a function of automatically changing the navigation image and the treatment parameter can be provided.

When the above-described operation is performed inside the gantry of the MRI apparatus 1 , the above-described information is fed back continuously and in real time to the ultrasound treatment system, and includes the same image including a simulated image of the ultrasound treatment probe 37 in the treatment target region. An MRI imaging cross-sectional image 508 and an ultrasonic image 509 can be displayed. That is, the surgeon 29 can use the two-dimensional real-time image obtained by the MRI apparatus 1 and the three-dimensional image information obtained by navigation for treatment as necessary. As one application of the high-speed imaging sequence of the MRI apparatus 1, a real-time dynamic imaging method called fluoroscopy (fluoroscopic imaging) is being clinically applied. In fluoroscopy, by repeating imaging and image reconstruction with a period of about 1 second or less, it can be used to extract the dynamics of internal tissues and grasp the position of an instrument inserted from the outside like a fluoroscopic imaging. Generate and display dynamic images. This application is also applied to three-dimensional high-speed imaging.

  FIG. 6 shows a flowchart of the processing procedure of an embodiment of the ultrasonic therapy system of the present invention. First, a plurality of three-dimensional volume imaging and three-dimensional image reconstruction are performed using the MRI apparatus 1 (S1). Next, a specific area (segmentation) in which treatment is indispensable is depicted from the three-dimensional image by image processing (S2). Based on the rendered image including the specific area, the area that allows HIFU irradiation and the area that cannot be irradiated are discriminated and set (S3). Next, a treatment scheduled area and a margin area including them are set (S4). After inputting parameters necessary for HIFU irradiation (S5), the HIFU treatment plan is executed to simulate the position of the ultrasonic treatment probe 37 (S6). After the treatment plan, the operation support guidance function such as navigation is activated (S7), and the operation is started (S8).

At the time of surgery, following the change in the position of the ultrasound treatment probe 37, a simulated image showing the focus position 403 of the treatment probe 37a and the treatment ultrasound beam bundle 404 that is the HIFU irradiation path is superimposed and displayed on the navigation image ( S9). Thereby, the surgeon 29 guides the ultrasonic therapy probe 37 to the planned treatment position (target position) using the images and numerical information displayed on the monitor 38 and the GUI (S10). After the guidance, the position of the target is confirmed with an MR image (for example, a blood flow image) or an ultrasonic image (elastography) (S11).

Next, the body surface (skin) of the living body is drawn from the ultrasonic image and the MR image (S12). Then, based on the position of the treatment probe 37a detected by the position detection device 9, the position data of each treatment transducer 39 stored in advance is determined, and the treatment that is emitted from each treatment transducer 39 and reaches the focal point 403 is performed. A simulated image of the ultrasonic beam 404a is drawn on at least one of the ultrasonic image and the MR image. Based on the simulated image, the incident angle of the therapeutic ultrasonic beam 404a on the body surface is calculated (S13). Correction for compensating the intensity of the therapeutic ultrasonic beam 404a of each therapeutic transducer 39, which decreases according to the calculated incident angles of all the therapeutic ultrasonic beams 404a, is performed (S14). After compensation, simultaneously with the start of HIFU treatment, monitoring is performed using MR images or ultrasonic diagnostic images, and the course of treatment is recorded as appropriate (S15). These processes are repeated a plurality of times for the region to be treated, and after confirming the therapeutic effect (S16), the presence or absence of the need for additional treatment is confirmed, and the process ends (S17).

Figure 7 shows a flowchart of a detailed procedure of S 14 of FIG. 1 is a characteristic portion of the present invention. The incident angle of the therapeutic ultrasound beams 404a emitted from each treatment vibrator 39 calculated in S 13 of FIG. 1, determines allowable incident angle range or a preset (S21). If even one of the therapeutic ultrasound beams 404a is outside the allowable incident angle range, the operator 29 is notified and warned that one or more of the depicted incident angles are outside the allowable incident angle range (S22). Then, the operator 29 is inquired as to whether or not to change the position of the ultrasonic therapy probe 37 and is left to the judgment of the operator 29 (S23). Determination of the operator 29 with respect to this, when changing the position of the ultrasound therapy probe 37 returns to S 9 in FIG. If the judgment does not change the position of the ultrasonic treatment probe 37, the process proceeds to S 25 described later.

On the other hand, when the incident angle of the therapeutic ultrasonic beam 404a emitted from the therapeutic transducer 39 is within the specified range, the operator 29 is notified of this fact (S24). Then, the intensity of the therapeutic ultrasonic beam 404a that decreases in accordance with the incident angle of the therapeutic ultrasonic beam 404a is compensated (S25).
Next, it is checked whether or not there is a concern about skin burns due to the intensity of the compensated therapeutic ultrasonic beam 404a, that is, whether or not the upper limit value of the set therapeutic ultrasonic beam 404a is exceeded (S26). Then, if there is a concern about skin burns due to the compensated therapeutic ultrasonic beam 404a, a warning is given and the movement of the position of the ultrasonic therapeutic probe 37 is recommended (S27). In addition, when skin burns are not a concern due to the intensity of the compensated treatment ultrasonic beam 404a, the operator 29 is notified of the setting conditions including the intensity of the treatment ultrasonic beam 404a corresponding to each treatment transducer 39, and treatment is performed. Urges final decision to be made (S28). In addition, after recommending the movement of the position of the ultrasonic therapy probe 37 in S 27, it is possible to proceed to S 28 and notify the operator 29 of the set conditions so as to prompt the final decision on treatment. That is, the number of therapeutic ultrasound beams 404a that are likely to cause skin burns and the intensity of the compensated therapeutic ultrasound beam 404a are presented, and treatment is started when the operator 29 determines that there is no problem.

  FIG. 8 (a) shows an example of irradiation of the therapeutic ultrasonic beam 404a by each therapeutic transducer 39 of the therapeutic probe 37a. Here, for convenience of explanation, the plurality of divided treatment transducers 39 are referred to as channels for emitting treatment ultrasonic waves. As shown in FIG. 8 (b), the concave surface is divided into a plurality of concentric annular regions i (i = 5 in the illustrated example), and the annular region is further divided into a plurality of regions j in the radial direction (in the illustrated example). , J = 8), and a plurality of channels Cij are provided. The therapeutic ultrasound beam 404a emitted from each channel Cij is focused on the focal point 403. That is, by independently controlling the phase of each treatment transducer 39, the emission angles of the plurality of treatment ultrasonic beams 404a can be controlled and focused on the focal point 403. The focal point 403 can be moved in three dimensions (front and rear, left and right, depth direction).

FIG. 9 shows pulse patterns of HIFU irradiated from the channels Cij in FIG. 8 (b). The treatment is performed by irradiating the trigger pulse 801 and the heating pulse 803 alternately and alternately for the set times 802 and 804, respectively, and irradiating with the total set time 805. The two-dimensionally arranged channels Cij are basically driven by the same pulse pattern to perform treatment.
The trigger pulse 801 is an instantaneous high-intensity pulse for generating bubbles, and the heating pulse 803 is composed of a continuous wave that pulverizes the generated bubbles to induce thermal coagulation. For example, a trigger pulse 801 having a trigger intensity 806 is applied for a set time (for example, several ms) 802, and then a heating pulse 803 having a heating intensity 808 is applied for a set time 804. This pulse pattern is defined by the number of repetitions per second: Pulse Repetition Frequency (PRF) 809 and a total setting time 805, which defines the HIFU intensity. That is, by controlling the amplitude, frequency, and set time of the trigger pulse 801 and the heating pulse 803 , the HIFU intensity or the intensity of the therapeutic ultrasonic beam (the energy of the therapeutic ultrasonic wave) can be controlled.

For example, if the setting time 802 of the trigger pulse 801 is set long and the PRF 809 is set small, bubbles are easily generated, but it is possible to cause burns by concentrating energy on the skin through which the treatment ultrasonic beam 404a passes. Increases nature. However, there is a conflicting feature that the ablation range in the treatment target region is increased and the treatment effect can be improved. That is, when the trigger pulse is irradiated for PRF times × trigger setting time 802 per second, the cavitation occurrence rate increases in proportion to the irradiation time of the trigger pulse 801, but the concern of skin burns increases. Patent Document 2 introduces the content of transmitting a pulse for generating bubbles and a pulse for increasing the diameter of the generated bubbles to a target region of a living body. As a result, it is possible to realize an embolization treatment that is minimally invasive and has a high blood flow blocking effect.

Referring to FIG. 10, the angle (incidence angle θij) at which the therapeutic ultrasound beam 404a emitted from each channel Cij is incident on the body surface (skin) of the living body is calculated, and each channel Cij is determined according to the incident angle θij. An intensity compensation method according to an embodiment of the present invention for compensating the intensity of the therapeutic ultrasound beam 404a will be described.
(Calculation of incident angle)
Based on the ultrasonic image displayed on the monitor 38, the HIFU controller 49 calculates the incident angle θij of the therapeutic ultrasonic beam 404a irradiated to the focal point 403 from each therapeutic transducer 39 with respect to the body surface 900 of the living body. It has become. Further, the HIFU controller 49 compensates the intensity of the therapeutic ultrasonic beam 404a emitted from each channel Cij corresponding to each therapeutic transducer 39 according to the incident angle θij of the therapeutic ultrasonic beam 404a. . That is, the HIFU controller 49 detects the position (position and posture) of the treatment probe 37a with the position detection device 9, and based on the ultrasonic image of the imaging probe 37b assembled integrally with the treatment probe 37a, A three-dimensional positional relationship with the focal point 403 is obtained. In other words, based on the pre-registered geometry of the treatment probe 37a and the position data of each channel Cij, a simulated image of the treatment ultrasound beam 404a emitted from each channel Cij is drawn based on the real-time ultrasound image. Then, the incident angle θij formed with the body surface 900 that can be identified from the change in luminance of the ultrasonic image is calculated. This calculation is performed three-dimensionally. Here, in the illustrated example of the incident angle θij, the angle formed between the body surface 900 and the straight line connecting the edge of each treatment transducer 39 and the focal point 403 is obtained, but the present invention is not limited to this, The angle formed by the body surface 900 and the straight line connecting the center of the area of the treatment transducer 39 and the focal point 403 may be obtained.

Further, the HIFU controller 49 is configured to issue an alarm by sound or display when the calculated therapeutic ultrasound beam 404a, that is, the incident angle θij of the channel Cij exceeds a predetermined allowable incident angle range. ing.
(Detection of body surface)
The body surface 900 may have a different positional relationship depending on the three-dimensional position of each channel Cij. Therefore, the tomographic plane (scan plane) position of the two-dimensional ultrasonic image shown in FIG. 10 (a) is obtained based on the position information of the imaging probe. Next, the personal computer 19 reads the volume data of the MR image, generates a three-dimensional MR image by a rendering method, and displays it on the monitor 38. In addition, a three-dimensional simulated image of the therapeutic ultrasound beam 404a is generated and superimposed on the three-dimensional MR image. Based on the three-dimensional MR image of the body surface 900 of the displayed three-dimensional MR image and the three-dimensional simulation image of the treatment ultrasonic beam 404a, the HIFU controller 49 determines the incident angles θij of all the treatment ultrasonic beams 404a with respect to the body surface 900. Is calculated.

Note that the angles at which the therapeutic ultrasound beams 404a of all the channels Cij are incident on the body surface 900 can be calculated without using a three-dimensional MR image. For example, the HIFU controller 49 rotates the tomographic plane (scanning plane) of the two-dimensional ultrasonic image around the main axis (line connecting the probe center and the focal point) of the treatment probe 37a, and the ultrasonic wave at an arbitrary rotational position. An MR image corresponding to the tomographic plane of the image is cut out from the volume data, and a simulated image of the therapeutic ultrasound beam 404a is superimposed and displayed. Thereby, the HIFU controller 49 can calculate the three-dimensional incident angle θij.
(Intensity compensation of therapeutic ultrasonic beam)
When the incident angle θij is 90 degrees, the therapeutic ultrasound beam 404a is irradiated to the focal point 403 without being reflected by the body surface 900. Here, the incident angle θij is defined as an acute angle range of 0 to 90 degrees. When the incident angle θij is smaller than 90 degrees, the treatment ultrasonic beam 404a is reflected or absorbed by the body surface 900 according to the incident angle θij, and the HIFU intensity irradiated to the focal point 403 decreases. The amount of decrease is compensated, and the HIFU intensity irradiated to the focal point 403 is corrected to be maintained at the target value. In other words, compensation is performed according to the incident angle θij so that the intensity of the treatment ultrasonic beam 404a irradiated from the treatment transducer 39 of each channel Cij to the focal point 403 becomes 100% of the target value of each treatment transducer 39. To do.

FIG. 10 (b) shows a setting example of a compensation graph of the therapeutic ultrasonic beam intensity of the channel Cij, with the incident angle θij as the horizontal axis and the intensity of the therapeutic ultrasonic beam 404a of each channel Cij after compensation as the vertical axis. . In the figure, the therapeutic ultrasonic beam intensity E1 is the target value 100% of each channel Cij, and the therapeutic ultrasonic beam intensities E2 and E3 are intensities after compensation. The compensation graph is a curve as shown in the illustrated example, but the compensation is made such that the incident angle θ is in the range of 70 to 90 degrees as the allowable incident angle. That is, in the HIFU controller 49, a value for compensating the intensity of the therapeutic ultrasonic beam 404a emitted from each channel Cij corresponding to each therapeutic transducer 39 is determined in advance according to the incident angle θij of the therapeutic ultrasonic beam 404a. It has been. In the present invention, the allowable incident angle θ is not limited to a range of 70 to 90 degrees, but it is desirable to set in consideration of skin burns in order to widen the compensation range of the incident angle θ. For example, the compensation intensity when the incident angle θ is 70 to 90 degrees corresponds to between E1 and E2 of the compensation graph. The incident angle θ in that range is automatically compensated. On the other hand, if the surgeon 29 authenticates, the incident angle θ in the range of 70 degrees or less can be compensated. However, since there are concerns about side effects such as burns, a warning prompting the user to accept the risk of actual irradiation is displayed on the GUI.

The incident angle θij calculated in this way is registered in the database shown in FIG.
The database contains channel numbers. It is composed of incident angle θ (°), allowable incident angle (°), whether it is within the allowable range (○ mark is within the allowable range), treatment ultrasonic beam intensity (compensation magnification) predefined by the operator 29 Yes. Further, the compensated therapeutic ultrasound beam intensity of each channel Cij can be imaged and displayed so as to be distinguishable by hue, shading, or a combination thereof depending on the intensity. As a result, the channel result after treatment ultrasonic beam intensity compensation can be seen at a glance. In accordance with the therapeutic ultrasonic beam intensity (compensation magnification) registered in the database, compensation is automatically made when the therapeutic ultrasonic beam from the corresponding channel Cij is irradiated.

Further, the ultrasonic image constructing unit 45 includes a treatment probe image composing unit that generates a simulated image representing the arrangement of the plurality of treatment transducers 39 of the treatment probe 37a and renders it on the monitor 38. Furthermore, the treatment probe image configuration unit changes the display hue or shading of the simulated image of each treatment transducer 39 according to the intensity of the treatment ultrasonic beam 404a corrected by the HIFU controller 49 , and the treatment probe shown in FIG. An image 1008 is displayed on the monitor 38. Further, the bar display 1009 represents the intensity of the therapeutic ultrasonic beam 404a corresponding to the display hue or shading of the simulated image. Thus, the surgeon can recognize the intensity of the treatment ultrasonic beam 404a of each channel Cij at a glance by looking at the treatment probe image 1008 and the bar display 1009.

FIG. 12 shows a GUI display example at the time of surgery / treatment of the present invention. By pressing the 3D imaging button 1101, the Axial section 1131, the Sagittal section 1132, the Coronal section 1133, and the Volume Rendering screen 1134 are reconstructed and displayed. When a segmentation button 1102 is pressed, segmentation / region extraction is performed automatically (or manually). Further, by depressing a HIFU irradiation enable / disable area setting button 1103, an ultrasound inaccessible area 1140 is identified in addition to the tumor area 1119 with respect to the drawn segmentation information. In addition, by pressing the treatment plan / margin setting button 1104, the HIFU 404 can be calculated in advance, and it can be guided along the treatment. These pieces of information can be freely rotated on the Volume Rendering screen 1134 and can be observed from different viewpoints / angles. Also, a tumor region (treatment target site) 1119 and a margin region 1120 including them are set.

Here, by pressing a treatment parameter setting button 1105, a treatment parameter for a tumor region (treatment target site) 1119 can be input. Specific input values include the type, shape, output intensity, and unit output intensity for each channel of the treatment probe 37a.
At the time of actual surgery, by pressing a navigation button 1106, a surgery support function such as equipment necessary for treatment and navigation operates in conjunction with each other. The position of the ultrasonic therapy probe 37 is detected and superimposed on the Axial cross section 1131, the sagittal cross section 1132, the coronal cross section 1133, and the volume rendering screen 1134. The surgeon guides the ultrasonic therapy probe 37 with reference to the treatment path 1138 obtained in advance.

In addition, the past position of the ultrasound treatment probe 37 can be displayed, and the information screen 1125 includes the difference between the tumor area and the treatment area as the log information in addition to the treatment progress and biological information, the number of treatments, the time, the ratio, and the remaining treatment. The frequency schedule can also be displayed in real time as surgery information. By pressing the channel intensity compensation button 1107 immediately before the treatment, the incident angle between the treatment ultrasonic beam 404a and the body surface 900 with respect to the focal point 403 is calculated, and a database as probe information 1111 is created. Further, the compensation information of the therapeutic ultrasonic beam intensity that is made into a database can be visualized for each channel.

The personal computer 19 also has a warning function that prompts the position change of the ultrasound treatment probe 37 when the irradiation path of the HIFU 404 passes through the ultrasound inaccessible area 1140. By displaying these information on the navigation image immediately before the treatment, the information is visually transmitted to the operator 29 . By pressing the HIFU irradiation and effects confirmation button 1108, the therapeutic ultrasonic waves and imaging ultrasonic waves are irradiated alternately, treatment information and ultrasound image 1117 of the treated area 1118 to the treatment target site 1119 is displayed in real time, each species Information and warning information can also be displayed. For example, a previously treated region 1118 that has been treated in the past can be displayed in a superimposed manner, and a function that issues a warning can be automatically turned ON / OFF when the region exceeds the scheduled treatment region or when an abnormality occurs in the patient. In addition to the treatment target region 1119, “remaining treatment region = treatment target region 1119−treated region 1118” and a margin region 1120 are also displayed. As a result, the operator can visually recognize the remaining treatment area, and if under the MRI, the MRI imaging and the ultrasonic imaging are also provided with a function of alternately imaging. On the MR image, the specific area, the margin area, and the ARFI treatment planned area are displayed in the same manner, and images with different tissue contrasts are displayed. The operator 29 determines whether or not to perform retreatment from the image information 1131 to 1134 before and after treatment and the operation progress information, and retreats as necessary.
Another advantage of MRI is that it can be imaged deep into the body. As a result, the surgeon can move the surgical tool and perform additional treatment while viewing the previous treatment image. The information before and after the treatment can be linked with the surgical information 1125 in addition to the ultrasonic image 1117, the three-axis cross sections 1131 to 1133, the Volume Rendering image 1134, and the MR image.

  The ultrasonic therapy probe 37 supports not only manual operation by a human hand but also mechanical operation by a manipulator. The position information may be acquired from the position detection device 9 or may be displayed three-dimensionally 1131 to 1134 using coordinates by a manipulator.

As described above, the ultrasonic treatment apparatus of the present invention includes a treatment probe 37a for irradiating treatment ultrasonic waves from a plurality of treatment transducers 39 disposed on a hemispherical concave surface to a focal point 403 set on a living body, The HIFU controller 49, which is a treatment transducer control unit for controlling the intensity of the treatment ultrasonic beam 404a emitted from each treatment transducer 39, and the center of the concave surface of the treatment probe 37a are provided for imaging between the living body and the living body. An imaging probe 37b having a plurality of imaging transducers for transmitting and receiving ultrasonic waves, an ultrasonic image constructing unit 45 for generating an ultrasonic image including a focal point generated from a reception signal of the imaging probe, and ultrasonic waves And an HIFU controller 49 for displaying the image on the body surface 900 of the treatment ultrasound beam 404a irradiated from the treatment transducers 39 to the focal point 403 based on the ultrasound image displayed on the monitor 38. Calculate the incident angle θij, It is configured to compensate for the intensity of the therapeutic ultrasound beams 404a which decreases in accordance with the incident angle θij that issued.

  Furthermore, the ultrasonic treatment system of the present invention accumulates the position detection device 9 for detecting the position of the treatment probe 37a and the three-dimensional volume image data including the treatment target part of the living body in addition to the above-described ultrasonic treatment apparatus. The navigation image corresponding to the tomographic plane of the ultrasonic image is generated from the three-dimensional volume image data and displayed on the monitor 38 based on the position of the treatment probe 37a detected by the video recording device 34 and the position detection device 9 And an MRI apparatus 1 having a navigation image forming unit incorporated in the personal computer 19 to be configured.

  In particular, the MRI apparatus 1 includes a personal computer 19 incorporating a therapeutic ultrasound beam rendering unit that generates a simulated image of a therapeutic ultrasound beam that is focused on each treatment transducer and renders it superimposed on a navigation image. Further, the HIFU controller 49 calculates the incident angle θij of the therapeutic ultrasound beam 404a that is incident on the body surface 900 based on the simulated image of the therapeutic ultrasound beam 404a drawn on the navigation image. The therapeutic ultrasonic beam rendering unit generates a simulated image of the therapeutic transducer 39 disposed in a cross section passing through the central axis of the therapeutic probe 37a and superimposes it on the ultrasonic image.

  Further, the navigation image construction unit generates a three-dimensional navigation image and draws it on the monitor 38, and the therapeutic ultrasonic beam drawing unit generates a three-dimensional simulated image of the therapeutic ultrasonic beam 404a and overlays it on the three-dimensional navigation image. To draw on the monitor 38. Further, the HIFU controller 49 calculates the incident angle of the therapeutic ultrasound beam based on the three-dimensional navigation image drawn on the monitor 38 and the three-dimensional simulated image of the therapeutic ultrasound beam.

  Instead, the navigation image construction unit generates a two-dimensional navigation image corresponding to the tomographic plane of the ultrasonic image at a position obtained by rotating the tomographic plane of the two-dimensional ultrasonic image around the main axis of the treatment probe 37a. The treatment ultrasonic beam drawing unit generates a two-dimensional simulated image of the treatment ultrasonic beam at a position where the treatment probe 37a is virtually rotated and superimposes it on the two-dimensional navigation image on the monitor 38. Based on the two-dimensional navigation image drawn on the monitor 38 and the two-dimensional simulated image of the treatment ultrasonic beam 404a, the drawing HIFU controller 49 generates the treatment ultrasonic beam 404a at the position where the treatment probe 37a is virtually rotated. The incident angle can be calculated.

  As mentioned above, although this invention was demonstrated based on one Embodiment, this invention is not limited to these, It is possible to implement in the form deform | transformed or changed in the range of the main point of this invention. It will be obvious to those skilled in the art, and it is obvious that such modifications or alterations belong to the scope of the claims of the present application.

  DESCRIPTION OF SYMBOLS 1 ... MRI apparatus, 3 ... Upper magnet, 5 ... Lower magnet, 7 ... Support | pillar, 9 ... Position detection device, 11 ... Arm, 13, 14 ... Monitor, 15 ... Monitor support part, 17 ... Reference tool, 19 ... Personal computer , 21 ... bed, 23 ... control unit, 24 ... patient, 25 ... infrared camera, 27 ... pointer, 29 ... surgeon, 33 ... RS232C cable, 34 ... video recording device, 35 ... reflection sphere, 37 ... ultrasonic therapy probe , 37a ... treatment probe, 37b ... imaging probe, 38 ... monitor, 39 ... treatment transducer, 40 ... ultrasonic therapy device, 44 ... ultrasonic transmission / reception unit, 45 ... ultrasonic image construction unit, 47 ... ultrasonic control unit, 48 ... control panel, 49 ... HIFU controller

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