JP2006068102A - Ultrasonic treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ultrasonic treatment system capable of producing a functional image and a morphological image and determining the state of an affected part (tumor) on site by assembling a nuclear medicine diagnostic apparatus with an X-ray CT apparatus. <P>SOLUTION: The γ rays emitted from a subject are detected by radiation detectors 21B-21D. A radiation detector 21A disposed in an area A shielded by this ultrasonic treatment system 4 receives the γ rays attenuated by acoustic medium 42 and does not detect the γ rays. When the nuclear medicine diagnostic apparatus 2 is a PET (Positron Emission Computed Tomograph), the detection signals of the γ rays detected by the radiation detectors 21B-21D are processed by a coincidence method and reconstructed. When the nuclear medicine diagnostic apparatus 2 is a SPECT (Single Photon Emission Computed Tomograph), the detection signals are reconstructed without being processed by the coincidence method. The functional image data are produced by reconstructing the signals and composed with the morphological image generated by the X-ray CT apparatus to be displayed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrasound treatment apparatus that performs treatment by irradiating a subject with focused intense ultrasound. In particular, a nuclear medicine diagnostic apparatus capable of generating a functional image of a subject, called a positron emission CT apparatus or a single photon emission CT apparatus, and an object called an X-ray CT apparatus, an MRI apparatus, or an ultrasonic diagnostic apparatus. The present invention relates to an ultrasonic therapy apparatus including an imaging apparatus capable of generating a morphological image of a specimen.

  Generally, clinical diagnosis includes morphological diagnosis and functional diagnosis. What is important in clinical diagnosis is whether or not the tissue or organ functions normally due to a disease. In many diseases, anatomical morphological changes in tissues occur as functional abnormalities progress. An X-ray diagnostic apparatus and an X-ray CT apparatus are devices for this morphological diagnosis.

  On the other hand, a radioisotope (hereinafter abbreviated as RI) or its labeled compound is used to selectively take in specific tissues or organs in the living body, and γ rays emitted from the RI are There is a method of measuring from outside the body and imaging the RI dose distribution to make a diagnosis, which is called a nuclear medicine diagnostic method.

  In the nuclear medicine diagnostic method, the principle itself that the labeled substance is accumulated in a specific tissue or organ is linked to the physiological function of the tissue or organ and the biochemical substance metabolism function. In addition, functional diagnosis at an early stage of the lesion is possible. As this nuclear medicine diagnostic apparatus, a positron emission computed tomography (hereinafter referred to as a PET apparatus) or a single photon emission computed tomography (hereinafter referred to as a SPECT apparatus). is there.

  An apparatus using radiation, such as an X-ray CT apparatus, a PET apparatus, and a SPECT apparatus, measures a physical quantity of an integral value (flight direction) of radiation emitted from the human body, and backprojects the integral value to the human body. The physical quantity of each voxel is calculated and imaged.

  An X-ray CT apparatus is an apparatus that measures the intensity of X-rays that have passed through a subject, and images morphological information of the subject from the penetration rate of the X-ray beam in the body. The subject is irradiated with an X-ray beam from an X-ray source, the X-ray intensity that has passed through the body is measured by an X-ray detector disposed on the opposite side of the subject, and the integral absorption coefficient of the subject is calculated. An X-ray source and an X-ray detector are swung around the subject to measure the transmitted X-ray beam, and the integral series coefficient distribution in the body is obtained. From this integrated absorption coefficient, the absorption coefficient of each voxel is obtained using a filtered back projection method (Filtered Back Projection Method) or the like, and the value is converted into a CT value.

PET apparatus, positron emission ^{(15 O, 13 N, 11} C, 18 F , etc.), and a radioactive agent comprising a material having a gathering property to specific cells in the body is administered to a subject, and measuring the distribution This is a device for imaging. Radiopharmaceuticals include fluorodeoxyglucose (2- [F-18] fluoro-2-deoxy-D-glucose, ¹⁸ FDG) and the like. Used to identify the site. Radionuclides taken into the body decay and release positron (β +). The emitted positron combines with electrons and emits a pair of annihilation gamma rays (positron annihilation lines) having energy of 511 keV when annihilating. Since this pair of γ rays is emitted in directions almost opposite to each other (180 ° ± 0.6 °), if this pair of annihilation γ rays is detected by a radiation detector, between which two radiation detectors You can see if the positron has been released. In this way, it is possible to simultaneously detect annihilation γ-ray pairs with a radiation detector arranged so as to surround the object, accumulate the radiation direction data, and obtain projection data. For example, since ¹⁸ FDG collects in cancer cells with intense glucose metabolism, a cancer lesion can be detected by a PET apparatus. It is possible to identify and image the radiation position (accumulation position of the radionuclide) from the positional relationship of the simultaneously measured detectors and the signal intensity information.

The SPECT apparatus is an apparatus that administers a radiopharmaceutical containing a single photon emitting nuclide to a subject, detects γ-rays emitted from the nuclide with a radiation detector, measures the distribution thereof, and forms an image. The energy of γ rays emitted from the single photon emission nuclide used at the time of inspection by the SPECT apparatus is several hundred keV. Since this γ ray is a single γ ray, its flight direction cannot be identified. Therefore, in the SPECT apparatus, a collimator made of lead or the like is inserted in front of the radiation detector, and projection data is obtained by detecting only γ rays from a specific direction. A SPECT device administers a radiopharmaceutical containing a substance having a property of accumulating in a specific tumor or molecule and a single photon emitting nuclide (such as ⁹⁹ Tc, ⁶⁷ Ga, ²⁰¹ Ti, etc.) to a subject, and generates from the radiopharmaceutical. The gamma ray is detected to identify a place where the radiopharmaceutical is distributed (for example, a place where cancer cells are present). Similar to a PET apparatus, image data is obtained by back projecting projection data using a filtered back projection method or the like. The difference from the PET apparatus is that the coincidence counting method is unnecessary because the generation position of a single gamma ray can be specified using a collimator.

  The PET device and the SPECT device can extract a site where radiopharmaceuticals are accumulated with good contrast in order to obtain a functional image using in vivo metabolism, but have a problem that the positional relationship with surrounding organs cannot be grasped. Therefore, in recent years, attention has been paid to a technique for performing a more advanced diagnosis by synthesizing a morphological image that is a tomographic image obtained by an X-ray CT apparatus and a functional image that is a tomographic image obtained by a PET apparatus or a SPECT apparatus. , Has begun to be used.

  An image obtained by combining a morphological image and a functional image (referred to as a combined tomographic image) includes discrimination information indicating whether the tumor is normal and three-dimensional position information. There are features that can be obtained in the field.

  On the other hand, when a living tissue is irradiated with focused intense ultrasound (HIFU), a portion where the ultrasonic energy density is high generates heat and is solidified. An ultrasonic therapy apparatus for treating cancer by cauterizing and necrotizing tumor tissue using this phenomenon has also been developed.

  Conventionally, the configuration of an ultrasonic therapy apparatus that has been proposed is roughly divided into the following two types according to an apparatus for monitoring an affected area, and there is no combination with other diagnostic apparatuses.

  As a first combination, there is a combination of an ultrasonic diagnostic apparatus and an ultrasonic treatment apparatus. A probe for an ultrasonic diagnostic apparatus is attached inside an ultrasonic applicator for an ultrasonic therapy apparatus, and diagnosis is performed mainly in the B mode. When the focused intense ultrasound is irradiated to the living tissue, the living tissue generates heat, and when the cauterization progresses, the affected area becomes close to a boiling state, so that cavitation (microbubbles) is generated and detected as a so-called “high echo”. It was estimated that shochu was completed by confirming this high echo.

  As a second combination, there is a combination of a magnetic resonance imaging apparatus (MRI apparatus) and an ultrasonic therapy apparatus. When an MRI apparatus is used, the vertical warm-up time of the MRI signal changes with temperature. Therefore, monitoring is performed using the change in the image value, and the phase of the MRI image changes under the influence of temperature. A method for monitoring by using this is proposed. By observing at 70 ° C. or higher at which protein denaturation occurs with an MRI apparatus and assuming that all cells were heat-denatured necrotic at 70 ° C. or higher, it was estimated that cauterization was possible at the stage of 70 ° C. or higher.

  Considering the portability of the apparatus, the diagnostic apparatus needs to be small, so the intensity of the focused high-power ultrasonic wave is different. However, since the same ultrasonic wave is used, a configuration combined with the ultrasonic diagnostic apparatus has been devised. However, in the case of ultrasound images, “temperature measurement” (measurement method that applies the change in sound velocity in living tissue depending on temperature) has not been put to practical use, so it is suitable for measuring temperature rise due to cauterization of the affected area. There is also the idea that it is not.

  On the other hand, in the MRI apparatus, the temperature dependence of the phase information in each pixel of the MRI image can be accurately measured by applying the fact that the temperature dependence hardly depends on the composition of the living tissue. I figured it out.

Further, there is known an ultrasonic therapeutic apparatus in which two or more radiation detectors (gamma probes) are combined with an ultrasonic applicator for an ultrasonic therapeutic apparatus (Patent Document 1). In this ultrasonic therapy apparatus, the position of a tumor in which ¹⁸ FDG or the like is accumulated is identified by using a gamma probe as a clue, and cauterized with focused high-power ultrasonic waves.

JP 2003-235863 (paragraph [0013], FIG. 3)

Both the ultrasonic diagnostic apparatus and the MRI apparatus can generate an image reflecting the affected tissue. However, because it does not reflect physiological function (in most cases, tumors have an increased metabolic function and ¹⁸ FDG accumulates), it is easy to identify on the spot whether the tumor is malignant or benign. There wasn't. Usually, in order to perform cauterization treatment immediately after diagnosis by an ultrasonic diagnostic apparatus or an MRI apparatus, it is necessary to confirm by another diagnostic method, specifically, a definitive diagnosis (such as biopsy and tissue examination).

  Coupling obtained by a combination of a PET apparatus and an X-ray CT apparatus (hereinafter referred to as a PET / CT apparatus) or a combination of a SPECT apparatus and an X-ray CT apparatus (hereinafter referred to as a SPECT / CT apparatus) Because the tomographic image includes a functional image and a morphological image (including information on the positional relationship between the tumor and the transducer), it is possible to make a judgment close to a definitive diagnosis on the spot, but it is combined with an ultrasonic therapy device. No device has been proposed.

  Ultrasonic applicators for ultrasonic therapy devices are piezoelectric ceramics (ultrasound transducers), electrodes, and acoustic media for propagating ultrasonic energy to living tissue (mostly degassed sterile water, physiological Salt water). When an ultrasonic therapy apparatus is combined with a PET / CT apparatus or a SPECT / CT apparatus, it is necessary to dispose this ultrasonic applicator between the affected area and the radiation detector. For this reason, the γ-rays are greatly attenuated by the acoustic medium of the ultrasonic applicator, and there is a problem that a blind spot that cannot be performed by the “coincidence method” performed in the PET apparatus occurs in some imaging regions. Due to such problems, conventionally, no proposal has been made for a PET / CT apparatus or a combination of a SPECT apparatus / CT apparatus and an ultrasonic treatment apparatus.

  In addition, the ultrasonic therapy apparatus described in Patent Document 1 is an effective apparatus when the shape of the tumor is as simple as a sphere. However, when the shape of the tumor is complicated, the entire image of the tumor cannot be grasped. There is a problem that it is difficult to confirm the site to be used.

  This invention solves the above-mentioned problem, by combining a nuclear medicine diagnostic apparatus consisting of a PET apparatus or a SPECT apparatus and an imaging apparatus consisting of an X-ray CT apparatus, etc., to generate a functional image and a morphological image, An object of the present invention is to provide an ultrasonic therapy apparatus that can easily identify whether a tumor is malignant or benign on the spot.

  In addition, by detecting the radiation in consideration of the position of the ultrasonic applicator provided in the ultrasonic therapy apparatus, a function image can be generated even if the ultrasonic therapy apparatus and the nuclear medicine diagnostic apparatus are combined. An object is to provide a sonication device.

  It is another object of the present invention to provide an ultrasonic therapy apparatus that makes it easy to determine the completion of cauterization based on pixel values (luminance, intensity, etc.) of a functional image generated by a nuclear medicine diagnostic apparatus.

  The invention according to claim 1 is an imaging device that generates a first tomographic image by irradiating a subject with X-rays or ultrasonic waves, or applying a gradient magnetic field and a high-frequency magnetic field, and the subject And a plurality of radiation detectors are installed, and radiation emitted from the radiopharmaceutical administered to the subject is detected by the plurality of radiation detectors to generate a second tomographic image of the subject. A nuclear medicine diagnostic apparatus; a display device that displays a combined tomogram obtained by combining the first tomogram and the second tomogram; and a region surrounded by the plurality of radiation detectors, An ultrasonic therapy apparatus comprising: an ultrasonic medium having an acoustic medium between a subject and irradiating a focused ultrasonic wave to an affected part of the subject.

  In the present invention, the imaging apparatus corresponds to, for example, any of an X-ray CT apparatus, an MRI apparatus, and an ultrasonic diagnostic apparatus. An X-ray CT apparatus includes an X-ray source and an X-ray detector with a subject interposed therebetween, and the X-ray detector detects X-rays irradiated from the X-ray source and transmitted through the subject. X-ray CT image (first tomographic image) is generated. The MRI apparatus applies a plurality of gradient magnetic fields and high-frequency magnetic fields to the subject, and generates a nuclear magnetic resonance image (first tomographic image) based on the projection data of the nuclear magnetic resonance signal obtained as a result. Is. The ultrasonic diagnostic apparatus irradiates an object with ultrasonic waves by an ultrasonic probe installed in an ultrasonic applicator and receives a reflected wave from the object, thereby obtaining an ultrasonic diagnostic image (first tomographic image). ). The first tomographic image generated by the imaging apparatus corresponds to the morphological image of the subject.

  The nuclear medicine diagnosis apparatus corresponds to a PET apparatus that is a positron emission CT apparatus or a SPECT apparatus that is a single photon emission CT apparatus, and the second tomogram generated by the nuclear medicine diagnosis apparatus is a function of the subject. Corresponds to an image.

  As in the present invention, by combining and displaying the first tomographic image corresponding to the morphological image and the second tomographic image corresponding to the functional image, the affected part to be irradiated with the focused ultrasonic wave by the ultrasonic applicator It becomes possible to judge the state of (tumor) on the spot.

  Invention of Claim 2 is an ultrasonic therapy apparatus of Claim 1, Comprising: The said radiation detector is arrange | positioned over the perimeter so that the said ultrasonic applicator may be surrounded, The said ultrasonic applicator is Radiation is detected by a detector arranged in a region other than the shielded region.

  Since the radiation is attenuated by the acoustic medium, the radiation detector installed in the portion shielded by the acoustic medium does not detect the radiation. Therefore, the radiation is detected by the radiation detector arranged in the other part, and a functional image is generated. For example, it is assumed that radiation that has not been detected due to the positional relationship between the ultrasonic applicator and the radiation source is not generated, and other radiation is detected. In the case of a PET apparatus, the position is measured by a coincidence method, and in the case of a SPECT apparatus, the position is measured by a collimator. By detecting radiation in this way, even if the ultrasonic applicator is installed in the imaging region of the nuclear medicine diagnostic apparatus, there may be some blind spots (regions where no radiation is detected), Imaging of an affected part (tumor) becomes possible. By applying this, it becomes possible to perform ablation treatment by irradiating ultrasound with an ultrasonic applicator while photographing with a nuclear medicine diagnostic device, so ablation while observing the state of ablation with a nuclear medicine diagnostic device. Treatment can be performed. The SPECT apparatus has an advantage that the blind spot is smaller than that of the PET apparatus.

  Invention of Claim 3 is an ultrasonic therapy apparatus in any one of Claim 1 or Claim 2, Comprising: The said ultrasonic applicator is freely installed / removed from the area | region enclosed by the said radiation detector. When the radiation is detected by the radiation detector of the nuclear medicine diagnostic apparatus, the ultrasonic applicator is moved outside the region surrounded by the radiation detection apparatus.

  The invention according to claim 4 is the ultrasonic treatment apparatus according to claim 1, further comprising a bed on which a subject is placed, in which a groove is formed, and the radiation detector Is installed around the bed, the acoustic medium is filled in the groove, and the ultrasonic applicator is installed in the acoustic medium.

  Invention of Claim 5 is an ultrasonic therapy apparatus of Claim 4, Comprising: The acoustic medium discharge means installed in the groove part formed in the said bed, and discharge | emits the said acoustic medium to the outer side of the said groove part And a moving means for moving the ultrasonic applicator to the outside of the region surrounded by the radiation detector along the groove.

  A sixth aspect of the present invention is the ultrasonic treatment apparatus according to any one of the first to fifth aspects, wherein the ultrasonic treatment apparatus has a predetermined length so as to cross the second tomographic image displayed on the display device. A first region-of-interest setting means for setting a region of interest consisting of a plurality of line segments, and a second value for sequentially calculating pixel values of the second tomographic image on the line segment set by the first region-of-interest setting unit. 1 pixel value calculation means, and the display device displays the pixel value calculated by the first pixel value calculation means.

  The invention according to claim 7 is the ultrasonic therapy apparatus according to any one of claims 1 to 5, wherein the predetermined area is included so as to include the second tomographic image displayed on the display device. A second region-of-interest setting unit for setting a region of interest, and an average pixel value or a total pixel value of the second tomographic image in the region of interest set by the second region-of-interest setting unit A second pixel value calculating means for calculating, calculating a change amount per unit time of the average pixel value or the total pixel value, and comparing the change amount per unit time with a preset value; Furthermore, it is characterized by having.

  The invention according to claim 8 is the ultrasonic therapy apparatus according to any one of claims 1 to 7, comprising marker setting means for setting a marker indicating a position to irradiate focused ultrasound. In addition, the display device displays a combined tomographic image obtained by combining the first tomographic image and the second tomographic image, and displays the set marker. .

  The invention according to claim 9 is the ultrasonic therapy apparatus according to any one of claims 1 to 8, further comprising position detection means for detecting a position of the ultrasonic applicator, and the display. The apparatus displays a combined tomographic image obtained by combining the first tomographic image and the second tomographic image, and on the combined tomographic image based on the position detected by the position detecting unit, the ultrasonic applicator. And a propagation path of the focused ultrasonic wave irradiated from the ultrasonic applicator is displayed.

  According to the first aspect of the present invention, for example, it is possible to generate a morphological image of a subject by X-rays and the like and to generate a functional image using a nuclear medicine diagnostic apparatus. Thus, the state (malignant or benign) of the affected part (tumor) to be treated can be determined on the spot. This eliminates the need for a separate diagnosis (such as biopsy), and enables ablation treatment immediately after image collection.

  According to the invention described in claim 2, by detecting radiation by a coincidence method with a part of the radiation detector, and further detecting radiation with a radiation detector other than the part shielded by the ultrasonic applicator, Even when the ultrasonic applicator is installed in the imaging region of the nuclear medicine diagnostic apparatus, it is possible to obtain a functional image of the affected part (tumor). This makes it possible to perform cauterization treatment while observing the state of the affected part (tumor) with a nuclear medicine diagnostic apparatus.

  According to the invention of claim 3 and claim 5, when imaging the affected part (tumor) with the nuclear medicine diagnostic apparatus, the ultrasonic applicator can be moved outside the imaging region of the nuclear medicine diagnostic apparatus, The radiation applicator is not shielded by the ultrasonic applicator, which makes it possible to detect radiation with all the radiation detectors.

  According to the invention described in claim 6, a region of interest is set so as to cross the second tomographic image generated by the nuclear medicine diagnostic apparatus, and a pixel value on the line segment is sequentially calculated to display the display device. By displaying the pixel value and observing the change of the pixel value, it becomes easy to confirm the progress of the cauterization. According to the invention of claim 7, the average pixel value or the total pixel value of the second tomographic image is sequentially calculated, and the amount of change per unit time is compared with a preset value (threshold value). This makes it easy to check the progress of shochu.

  According to the eighth aspect of the invention, the operator can easily identify the position of the affected part (tumor) to be irradiated by setting and displaying a marker indicating the ultrasonic irradiation position on the composite image. It becomes. According to the ninth aspect of the invention, the irradiation position can be easily confirmed by displaying the image of the ultrasonic applicator and the propagation path of the ultrasonic wave on the composite image.

  Hereinafter, an ultrasonic therapy apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10.

[First Embodiment]
An ultrasonic therapy apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing a schematic configuration of the ultrasonic therapy apparatus according to the first embodiment. FIG. 2 is a block diagram illustrating a schematic configuration of the ultrasonic therapy apparatus according to the first embodiment. FIG. 3 is a cross-sectional view taken along line AA ′ shown in FIG.

(Constitution)
First, the configuration of the ultrasonic therapy apparatus according to the first embodiment of the present invention will be described. The ultrasonic therapy apparatus 1 mainly includes a nuclear medicine diagnostic apparatus 2, an X-ray CT apparatus 3, an ultrasonic therapy unit 4, a bed apparatus 5, a control unit 6, an operation unit 7, and an image synthesis unit 8. And a display device 9. The nuclear medicine diagnosis apparatus 2 and the X-ray CT apparatus 3 are arranged so that their rotation centers are common.

The nuclear medicine diagnosis apparatus 2 includes a plurality of radiation detectors 21 and a collimator 56 with a rotation mechanism placed on the front surface thereof (which is an essential configuration in the case of a SPECT apparatus, but is not necessary in the case of a PET apparatus), A pulse generator 22, a counting device 23, a storage device 24, and an image reconstruction unit 25 are provided. The nuclear medicine diagnostic apparatus 2 has a hole 10 into which a subject is inserted for examination, and a plurality of radiation detectors 21 are arranged around the hole 10 in an annular shape. The plurality of radiation detectors 21 are, for example, gamma ray detectors including a scintillation crystal made of Bi ₄ Ge ₃ O ₁₂ (BGO) or the like and a photomultiplier tube (PMT). A semiconductor radiation detector may be used as the radiation detector 21. The radiation detector 21 detects γ rays emitted from the subject and outputs a detection signal (hereinafter referred to as a γ ray detection signal) of the γ rays.

  The pulse generator 22 receives the γ-ray detection signal output from the radiation detector 21 and generates a pulse signal having γ-ray energy. The counting device 23 obtains a count value for the γ-ray detection signal using the pulse signal output from the pulse generator 22 and stores the count value data in the storage device 24. Further, in the case of a PET apparatus, the counting device 23 receives the pulse signal output from the pulse generator 22 and performs simultaneous counting for each γ ray pair to obtain a count value, and sets the detection point to the position of γ ray detection. Data is converted into information, and the data is stored in the storage device 24. In the case of a SPECT device, the position can be determined by a collimator, and the count value and the position data at that time are stored in the storage device 24. The image reconstruction unit 25 reconstructs functional image data based on the count value, and outputs the functional image data to the image composition unit 8 and the storage device 24.

  The X-ray CT apparatus 3 has the same configuration as a known X-ray CT apparatus, and supports an X-ray generation source 31, a plurality of X-ray detectors 32, an X-ray generation source 31 and an X detector 32. And a rotation mechanism section (not shown) that rotates the rotation support section around the rotation center. Furthermore, the data collection unit 35, the collected data storage device 36, and the image reconstruction unit 37 are provided.

  The X-ray CT apparatus 3 has a hole 10 that is an observation region into which a subject is inserted for examination. The X-ray generation source 31 and the plurality of X-ray detectors 32 include the hole 10. It is arranged in the opposite direction of about 180 ° across. The X-ray generation source 31 and the plurality of X-ray detectors 32 can turn around the hole 10 by a rotation mechanism.

  The X-ray CT apparatus 3, for example, exposes an X-ray beam while rotating around the subject from the X-ray generation source 31 and moves the subject in the body axis direction so that the subject is spiraled. Scan (helical scan).

  The control unit 6 outputs an X-ray generation control signal for controlling X-ray generation to the X-ray control device 34, and also outputs a detection control signal indicating the detection timing of the X-ray beam and a data acquisition control signal for data collection. The data is output to the data collection unit 35.

  The X-ray controller 34 controls the timing of high voltage generation by the high voltage generator 33 based on the X-ray generation control signal output by the control unit 6. The high voltage generator 33 supplies a high voltage for exposing the X-ray beam to the X-ray generation source 31 in accordance with a control signal from the X-ray control unit 34.

  The X-ray generation source 31 emits a fan-shaped X-ray beam having a thickness in the slice direction toward the subject from multiple directions by the high voltage supplied from the high voltage generator 33. The X-ray detector 32 detects an X-ray beam that is exposed from the X-ray generation source 31 and transmitted through the subject.

  The data acquisition unit 35 amplifies the output current from the X-ray detector 32 based on the data acquisition control signal output by the control unit 6 and then converts the current into digital data, thereby converting the X-ray transmittance for each X-ray path. Collect and output the projection data reflected in. The collected data storage device 36 stores cross-section projection data collected by the data collecting unit 35.

  The image reconstruction unit 37 reconstructs a tomographic image of the subject based on the cross-section projection data. The reconstructed tomographic image data is output to the image composition unit 8 and the collected data storage device 36.

  The couch device 5 includes a couch top plate 51 on which a subject is placed, a couch top plate vertical movement mechanism unit 52 whose base is fixed to the floor, a couch top plate moving unit 53, and a couch control unit 54. It is prepared for. The couch top 51 is inserted into the hole 10 of the nuclear medicine diagnostic apparatus 2 and the hole 10 of the X-ray CT apparatus 3 and is movable in the longitudinal direction. A groove portion 55 is formed in the bed top plate 51, and the ultrasonic treatment unit 4 is disposed in the groove portion 55.

  The couch controller 54 outputs a couch movement signal to the couch top plate moving unit 53 and the couch top plate moving mechanism 52 based on the couch control signal output by the controller 6. The couchtop moving unit 53 moves the couchtop 51 horizontally in the longitudinal direction based on the couch movement signal, and the couchtop vertical movement mechanism 52 moves the couchtop 51 up and down.

  The ultrasonic treatment unit 4 includes an ultrasonic applicator 41, an acoustic medium 42, a holding member 43 that holds the ultrasonic applicator 41 so as to be movable in the longitudinal direction, a phase control circuit unit 44, and a drive circuit unit 45. , And an applicator position detection device 46.

  The ultrasonic applicator 41 includes a circular flat plate ultrasonic transducer that irradiates a therapeutic high-power ultrasonic wave. As the acoustic medium 42, for example, degassed sterilized water or physiological saline is used. An ultrasonic applicator 41 is installed in a groove 55 formed in the bed top plate 51, and an acoustic medium 42 made of sterilized water or the like is filled around the ultrasonic applicator 41. The ultrasonic applicator 41 can be moved in the longitudinal direction in the acoustic medium 42 by a holding member 43. Although not shown in FIG. 2, the holding member 43 is connected to the control unit 6 and moves the ultrasonic applicator 41 in accordance with an instruction from the operation unit 7. The holding member 43 corresponds to the “moving means” of the present invention.

  As the ultrasonic applicator 41 of the present embodiment, a phased array ultrasonic applicator is used. By controlling the drive timing of the drive circuit unit 45 by the phase control circuit unit 44, the focal position, the sound field, and the heating / heating region can be operated without moving the ultrasonic applicator 41. The drive circuit unit 45 is divided into channels corresponding to the number of divided ultrasonic transducers, and is driven by an independent timing signal delayed by the phase control circuit unit 44 by a signal from the control unit 6.

  For example, the applicator position detection device 46 detects the relative position of the ultrasonic applicator 41 with respect to the couch top 51 and outputs the signal to the control unit 6.

  Furthermore, an ultrasonic diagnostic apparatus 47 that can monitor the affected area of the subject in real time may be provided. Specifically, like the ultrasonic applicator described in Patent Document 1, an ultrasonic probe for imaging an ultrasonic diagnostic image is provided in the center of the ultrasonic transducer of the ultrasonic applicator 41. When an ultrasonic probe for ultrasonic diagnostic imaging is provided, first, the rough position of the affected part of the subject is confirmed by the ultrasonic probe, and then a tomographic image is obtained by the nuclear medicine diagnostic apparatus 2 and the X-ray CT apparatus 3. Take a picture and confirm the detailed location of the affected area. In this way, by confirming the rough position of the affected area with the ultrasonic probe for ultrasonic diagnostic imaging, it becomes possible to find the affected area relatively easily, and the convenience of the ultrasonic therapy apparatus can be improved. It becomes.

  The operation unit 7 is for inputting various instruction information from the operator to the ultrasonic therapy apparatus 1. The console 7 is provided with various input devices such as a trackball and a keyboard. Via this operation unit 7, setting of scanning conditions, setting of markers, and other various setting conditions are input. The operation unit 7 is used to set a region of interest, a marker, and the like, which will be described later.

  Next, the arrangement of the radiation detector 21 and the ultrasonic applicator 41 in the ultrasonic treatment unit 4 when the nuclear medicine diagnosis apparatus 2 is a PET apparatus will be described in detail with reference to FIG. The nuclear medicine diagnosis apparatus 2 has a large number of radiation detectors 21 installed in an annular shape inside an annular holding member (not shown). A through-hole 10 that is an observation region into which the couch top 51 is inserted is formed inside a large number of radiation detectors 21. The annular holding member is installed on a support member (not shown), and the support member is installed on the floor of the examination room. When the nuclear medicine diagnostic apparatus 2 is a SPECT apparatus, the collimator 56 with a rotation mechanism in FIG. 11 is added in front of the radiation detector 21.

  In the present embodiment, the cross section of the nuclear medicine diagnostic apparatus 2 shown in FIG. 3 is divided into four regions A to D by two virtual lines (broken lines shown in FIG. 3) passing through the center point O of the nuclear medicine diagnostic apparatus 2. It is divided into two areas. These two virtual lines pass through the center point O and are set to pass through the end of the bed top 51 of the ultrasonic therapy apparatus 4.

  Of the radiation detectors 21 arranged in the regions A to D, the radiation detector 21A arranged in the region A does not detect γ rays. The ultrasonic treatment unit 4 is arranged between the radiation detector 21A arranged in the region A and the affected part of the subject, and the γ rays emitted from the affected part are acoustic media constituting the ultrasonic treatment unit 4 This is because it is attenuated by 42.

  Therefore, γ-rays are detected by the radiation detector 21 arranged in a portion other than the region A shielded by the ultrasonic treatment unit 4. Since the arrangement position of the ultrasonic treatment unit 4 is known in advance, for example, the radiation detector arranged in the region A shielded by the ultrasonic treatment unit 4 with the center point O of the nuclear medicine diagnostic apparatus 2 as the axis of symmetry Γ-rays are detected by the radiation detector 21B arranged at a point-symmetrical position (region B) with respect to 21A. Further, γ rays are also detected by the radiation detectors 21C and 21D arranged in the region C and the region D on both sides of the radiation detector 21B.

  When the nuclear medicine diagnostic apparatus 2 is a PET apparatus, the radiation detectors 21 </ b> A to 21 </ b> D are connected to the pulse generator 22, and all γ-ray detection signals are output to the counting device 23. The gamma ray detection signal output by the radiation detector 21B arranged in the region B, the radiation detector 21C arranged in the region C, and the radiation detector 21D arranged in the region D is subjected to a coincidence counting method by the counting device 23. However, the γ-ray detection signal output by the radiation detector 21B arranged in the region B is regarded as having no generation of γ-rays and is not processed by the coincidence method. In the case where the nuclear medicine diagnostic apparatus 2 is a SPECT apparatus, the position is specified by a collimator, so that the simultaneous counting method is not performed and the process is performed.

  In this embodiment, the two virtual lines are set so as to pass through the end of the bed top 51 and the areas A to D are set. However, the bed top 51 is made of a material that does not attenuate γ rays. If so, the areas A to D may be set by setting a virtual line so as to pass through the end of the acoustic medium 42. In this case, since the detection areas of the radiation detectors 21C and 21D are expanded and the area processed by the coincidence counting method is expanded, the position information of the affected part (tumor) is increased, and the position is further easily identified.

(Operation)
Next, the operation of the ultrasonic therapy apparatus according to the first embodiment will be described. First, a radiopharmaceutical that is selectively taken into a tissue or organ in a region of interest of the subject is administered to the subject. Specifically, a radiopharmaceutical such as ¹⁸ FDG containing a positron emitting nuclide ( ¹⁵ O, ¹³ N, ¹¹ C, ¹⁸ F, etc.) is administered to the subject. Next, the subject is laid face down on the couch top 51. For example, the couch top 51 is moved horizontally in the right direction in FIG. 1 and moved from the X-ray CT apparatus 3 to the nuclear medicine diagnosis apparatus 2. . When the subject is laid on the couch top 51, the affected part of the subject is positioned on the ultrasonic treatment unit 4.

  When the bed top 51 on which the subject is placed passes through the X-ray CT apparatus 3, continuous X-ray projection data is collected by, for example, helical scanning. The moving speed of the couchtop 51 at this time is controlled so as to be synchronized with the rotating speed of the rotating mechanism unit 34 so that a desired slice pitch of the X-ray tomographic image can be obtained.

  The image reconstruction unit 37 reconstructs X-ray tomographic image data of the subject from the projection data stored in the acquired data storage device 36 and the reconstruction parameters, and outputs the X-ray tomographic image data to the image synthesis unit 8. To do. Further, the reconstructed X-ray tomographic image data is stored in the collected data storage unit 36. Note that “reconstruction parameters” include a reconstruction method (function), slice thickness, number of slices, and reconstruction interval. When reconstructing, these parameters are designated, and a plurality of two-dimensional images (tomographic images) are created.

  When the couch top 51 on which the subject is placed reaches the nuclear medicine diagnostic apparatus 2, it stops, and the nuclear medicine diagnostic apparatus 2 collects projection data. 511 keV gamma rays resulting from the radiopharmaceutical are emitted from the affected area of the subject. The plurality of radiation detectors 21 detect γ rays emitted from the subject and output γ ray detection signals. A number of gamma rays generated in the body of the subject due to the radiopharmaceutical are not emitted in a specific direction, but are emitted in all directions. As described above, these γ-rays are emitted in pairs in substantially opposite directions (180 ° ± 0.6 °) and detected by any one of the plurality of radiation detectors 21.

  In the present embodiment, γ rays are not detected by the radiation detector 21 </ b> A arranged in the area A shielded by the ultrasonic treatment unit 4. This is because the γ rays are attenuated by the acoustic medium 42 as described above. The gamma rays emitted from the subject are detected by the radiation detectors 21B to 21D. Among them, when the nuclear medicine diagnosis apparatus 2 is a PET apparatus, the detection signal of γ rays detected by the radiation detector 21 is processed by the coincidence method. Furthermore, when the nuclear medicine diagnosis apparatus 2 is a SPECT apparatus, the processing is performed without the coincidence counting method.

  Upon receiving the γ-ray detection signals output from the radiation detectors 21C and 21D, the pulse generator 22 generates a pulse signal having γ-ray energy. The counting device 23 performs simultaneous counting for each γ-ray pair using the pulse signal output from the pulse generator 22 and obtains a count value for the γ-ray detection signal. Furthermore, the counting device 23 has two detection points at which each γ-ray of the γ-ray pair is detected by a pair of pulse signals for the γ-ray pair (the direction is almost 180 ° different from the center point O of the nuclear medicine diagnostic device 2) The position of the paired radiation detectors 21) is converted into data as position information for γ-ray detection. A signal indicating the count value and the position information of the detection point is output from the counting device 23 to the reconstruction processing unit 25.

  Further, the detection signal of γ rays detected by the radiation detector 21B is output to the pulse generator 22 to generate a pulse signal having the energy of γ rays. The counting device 23 obtains a count value for the γ-ray detection signal using the pulse signal output from the pulse generator 22. This γ-ray detection signal is not processed by the coincidence method. A signal indicating the count value is output to the reconstruction processing unit 25.

  When the nuclear medicine diagnosis apparatus 2 is a PET apparatus, the reconstruction processing unit 25 reconstructs functional image data based on the count value obtained by the coincidence counting method and the position information of the detection points. When the nuclear medicine diagnostic apparatus 2 is a SPECT apparatus, the functional image data is reconstructed based on the count value obtained without the coincidence counting method and the position information of the detection points. The reconstructed functional image data is output from the reconstruction processing unit 25 to the image composition unit 8. Further, the reconstructed functional image data is stored in the storage device 24.

  The X-ray CT image data and the functional image data are combined by the image combining unit 8, combined tomographic image data of both data is generated, and the combined tomographic image is displayed on the monitor of the display device 9. A composite tomographic image displayed on the monitor of the display device 9 is shown in FIG. FIG. 4 is a view showing a composite image obtained by the ultrasonic therapy apparatus according to the first embodiment. On the monitor 9 a of the display device 9, the tomographic image obtained by the X-ray CT apparatus 3 and the tomographic image obtained by the nuclear medicine diagnostic apparatus 2 are displayed as a synthetic tomographic image 11. The tomographic image obtained by the X-ray CT apparatus 3 is represented as a morphological image of the subject, and the tomographic image obtained by the nuclear medicine diagnostic apparatus 2 is represented as a function (physiology) image of the affected part (tumor). The The image 11a is a morphological image obtained by the X-ray CT apparatus 3, and the image 11b is a functional image obtained by the nuclear medicine diagnostic apparatus 2.

  Further, as shown in FIG. 4A, a marker 12 indicating the position of the affected part (tumor) may be displayed on the monitor 9 a of the display device 9. In order to display the marker 12, a marker setting circuit 15 connected to the control unit 6 and the display device 9 is provided. When the operator operates the trackball or the like of the operation unit 7, the marker setting circuit 15 moves the pointer on the monitor of the display device 9 according to the operation signal via the control unit 6. When the marker surrounding the predetermined area is designated by the pointer, the marker setting circuit 15 receives the instruction from the operation unit 7 and displays the marker 12 on the monitor 9 a of the display device 9. The marker 12 can be moved and rotated on the monitor 9a of the display device 9 by operation from the operation unit 7, and the shape and size thereof can be changed. The marker setting circuit 15 receives the signal from the operation unit 7 and changes the shape, size, and position of the marker 12 on the monitor.

  Further, as shown in FIG. 4 (b), the propagation path 13 b of the focused powerful ultrasonic wave may be schematically displayed on the monitor 9 a of the display device 9. The relative position of the ultrasonic applicator 41 with respect to the bed top 51 is detected by the applicator position detection device 46 installed in the ultrasonic treatment unit 4, and the image 13 a of the ultrasonic applicator 41 is displayed on the monitor 9 a of the display device 9. Is displayed. The image 13a and the propagation path 13b of the ultrasonic applicator 41 are stored in advance in a storage device. The applicator position detection device 46 corresponds to the “position detection means” of the present invention.

  Since the approximate propagation path of the ultrasonic wave irradiated from the ultrasonic applicator 41 is known in advance, the propagation path 13b is drawn on the monitor 9a of the display device 9 using the image 13a of the ultrasonic applicator 41 as a base point. To do. This drawing is performed, for example, by the marker setting circuit 15 described above. The marker setting circuit 15 receives a signal indicating the position information output from the applicator position detection device 46 via the control unit 6, and displays the image 13 a of the ultrasonic applicator 41 on the monitor 9 a of the display device 9. . Further, the marker setting circuit 15 draws an approximate propagation path of the ultrasonic wave based on the image 13a of the ultrasonic applicator 41. By displaying the ultrasonic wave propagation path in this manner, the relationship between the ultrasonic irradiation position and the tumor position becomes clear, so that it is easy to determine whether or not the ultrasonic wave is being applied to the tumor.

  When the collection of projection data by the X-ray CT apparatus 3 and the nuclear medicine diagnostic apparatus 2 is completed, the focused applicator 41 of the ultrasonic treatment unit 4 irradiates the affected part of the subject with focused intense ultrasonic waves for ablation treatment. Start.

  As described above, the ultrasonic treatment unit 4 generates the functional image by detecting the γ rays by the radiation detectors 21B to 21D other than the radiation detector 21A in the portion where the ultrasonic treatment unit 4 is installed. Even if it is installed, a functional image can be generated. As a result, after the diagnosis is completed, it becomes possible to perform the cauterization treatment immediately, and it is possible to collect the functional image by the nuclear medicine diagnosis apparatus 2 while performing the cauterization treatment by irradiating the focused intense ultrasonic wave.

  Moreover, in the ultrasonic therapy apparatus 1 according to the present embodiment, it is possible to check whether or not the cauterization of the tumor tissue is completed by using the fact that the image being monitored is a functional image. . This operation will be described with reference to FIGS. 5 and 6 are diagrams showing a composite image and a spectrum of pixel values in an affected area.

  The ultrasound treatment apparatus 1 further includes a pixel value calculation unit 16 and a region of interest setting unit 17 connected to the control unit 6 and the display device 9. When a region to be noted is designated by an operation from the operation unit 7, the region of interest setting unit 17 via the control unit 6 displays a region of interest (ROI) on the monitor 9a of the display device 9 as shown in FIG. ) Is displayed. When the operator operates the operation unit 7, the region-of-interest setting unit 17 sets a region of interest (ROI) 14 represented by a line segment XY across the image 11 a obtained by the tumor and nuclear medicine diagnostic apparatus 2. It is displayed on the monitor 9a.

  When the line segment XY14 is set by the region-of-interest setting unit 17, the coordinates of the line segment XY14 are output to the pixel value calculation unit 16, and based on the coordinates, the pixel value calculation unit 16 via the control unit 6 stores the storage device 24. To read the functional image data located at the coordinates on the line segment XY14. Then, the pixel value calculation unit 24 sequentially calculates the pixel values (luminance, shade, etc.) of the functional image data at each coordinate on the line segment XY14, and the horizontal axis shown in FIGS. Then, a graph is created in which the vertical axis is represented by pixel values (luminance and shade). Then, these graphs are displayed on the monitor 9 a of the display device 9 via the control unit 6. The operator can confirm the progress of the shochu from these graphs, and can determine the completion of the shochu.

  FIG. 5B is a profile of pixel values of functional image data before irradiation with focused intense ultrasound. “Yama” has one shape in the profile before ultrasonic irradiation. When focused strong ultrasound is irradiated to the tumor in this state, as shown in FIG. 5 (c), the profile of the pixel value “Yama” has two shapes, and the peak value of the pixel value is shown in FIG. 5 (b). It becomes lower than that, and the area expands in the XY direction. When the irradiation is further continued, as shown in FIG. 5D, the peak value of the pixel value further decreases, and the region further expands in the XY direction. As described above, FIGS. 5B to 5D are graphs along a time series. In order to obtain these profiles, the pixel value calculation unit 16 sequentially calculates the pixel values of the functional image data every predetermined time and creates a graph.

When a living tissue is cauterized with an ultrasonic applicator and the state of cauterization is observed with an electron microscope, the cell nucleus and the cell wall remain intact, but the state in which the cell fluid has flowed out of the cell is observed. Therefore, radiopharmaceuticals such as ¹⁸ FDG are taken into cells and then stored in the cell fluid, and after irradiating focused intense ultrasound, the cell fluid containing ¹⁸ FDG leaches out of the cell edge. become.

It is possible to determine whether or not the cauterization is completed based on the facts from this observation and the profiles shown in FIGS. That is, it can be determined from the profile shown in FIG. 5B that the radiopharmaceutical is still taken into the cell and does not flow out of the cell. Further, the profile shown in FIG. 5 (c) has a lower pixel value than the profile shown in FIG. 5 (b) and spreads in the XY direction, so that the cell fluid containing the radiopharmaceutical is exposed outside the cells. It can be judged that it has leaked. Further, the profile shown in FIG. 5 (d) has a pixel value peak value lower than the profile shown in FIG. 5 (c) and spreads in the XY direction, so that the cell fluid further flows out of the cells. Can be judged. Therefore, by obtaining these profiles, it is possible to observe the progress of the ¹⁸ FDG concentration decay.

  In this way, the region of interest represented by the line segment is set so as to cross the tumor and the functional image, and the change in the pixel value of the functional image in the line segment is displayed as a graph on the monitor 9a of the display device 9. Thus, it is possible to check the progress of the shochu and determine whether or not the shochu has been completed. Moreover, in this embodiment, since it is possible to collect functional images while cauterizing as described above, cauterization can be performed while confirming the progress of cauterization with a graph on the monitor 9a.

  For example, the profiles shown in FIGS. 5B to 5D are displayed on the monitor 9a of the display device 9 together with the synthetic tomographic image 11 as shown in FIG. In this way, by displaying the composite tomographic image 11 and the profile at the same time, the change in the functional image of the composite tomographic image 11 is observed to determine the state of the ablation, and the change in the profile is observed to determine the state of the ablation. Since it becomes possible to judge, the information for judging a cautery state increases, and the judgment of a cautery state becomes still easier.

  Further, the region of interest is set so as to surround the margin of the tumor to be cauterized by the region of interest setting unit 17, the average pixel value in the region of interest is calculated by the pixel value calculating unit 16, and the average pixel value by cauterization is calculated. You may judge the state of shochu by observing a change.

Specifically, first, the pixel value calculation unit 16 calculates the average pixel value in the region of interest surrounding the margin of the tumor before cauterization. Next, the pixel value calculation unit 16 irradiates the tumor with focused intense ultrasound and sequentially calculates the average pixel value in the region of interest. The cell fluid containing ¹⁸ FDG flows out of the cell by cauterization and quickly dissipates. Therefore, it is considered that the decay time constant of the average pixel value increases after the dissipation. Here, the average pixel value is an average of the pixel values (luminance, density, etc.) of the functional image data at all coordinates included in the region of interest. The decay time constant of the average pixel value is a time until the average pixel value decreases by a constant value. The pixel value calculation unit 16 calculates an average pixel value and calculates an attenuation time constant of the average pixel value, that is, a time until the average pixel value decreases by a certain value. In other words, the pixel value calculation unit 16 calculates the change amount of the average pixel value per unit time (= change rate of the average pixel value).

  Immediately after the irradiation of focused high-power ultrasound, the amount of cell fluid that flows out of the cell is large, so the amount of change in the average pixel value is also large, and the time (decay time constant) until it decreases by a certain value is short. Become. If cauterization is continued, the amount of cell fluid that gradually flows out decreases, and the amount of change in the average pixel value also decreases. As a result, the time (decay time constant) until it decreases by a certain amount becomes longer. That is, if the decay time constant increases, it can be determined that cauterization has progressed and has been completed.

  In other words, immediately after irradiation, the amount of change in average pixel value per unit time (= change rate of average pixel value) is large, but the amount of change in average pixel value per unit time (= average pixel value) over time. Change rate) becomes smaller. That is, if the rate of change of the average pixel value decreases, it can be determined that cauterization has progressed and has been completed.

  Accordingly, it is possible to determine that the cauterization is completed when a threshold value is set in advance and the amount of change in the average pixel value per unit time (= change rate of the average pixel value) is equal to or less than the threshold value. Become. This preset threshold value is determined empirically and is the rate of change of the average pixel value indicating the completion of cauterization. The pixel value calculation unit 16 compares the preset threshold value with the change rate of the average pixel value. Further, the pixel value calculation unit 16 compares the change rate of the average pixel value with a threshold value, and determines whether or not cauterization is completed from the comparison result. The pixel value calculation unit 16 determines that the cauterization has been completed when the change rate of the average pixel value is equal to or less than the threshold value.

  Further, an attenuation time constant of the average pixel value may be calculated and compared with a preset threshold value. When the decay time constant becomes longer than the threshold value, it can be determined that the cauterization is completed. The threshold value set at this time is an attenuation time constant of an average pixel value indicating completion of cauterization.

  When the pixel value calculation unit 16 determines that the cauterization is completed by comparing the change rate or attenuation time constant of the average pixel value and the threshold value, the display device 9 displays an image indicating the completion of the cauterization. By the display, the operator can recognize the completion of the cauterization, and can determine the timing of the end of the irradiation of the focused powerful ultrasonic wave. Furthermore, when the pixel value calculation unit 16 determines that the cauterization is completed, the irradiation of the focused intense ultrasonic wave may be automatically stopped. A signal indicating the completion of cauterization is output from the pixel value calculation unit 16 to the control unit 6, and the control unit 6 stops outputting the signal to the phase control circuit unit 44 of the ultrasonic treatment unit 4, whereby the ultrasonic applicator 41. Stop irradiation. By automatically stopping the irradiation, it is possible to more easily determine the completion of the cauterization and to reduce the burden on the operator.

  In addition, instead of the average pixel value, the total pixel value may be used to determine cauterization. Here, the total pixel value is the sum of the image values (luminance, density, etc.) of the functional image data at all coordinates included in the region of interest.

  The pixel value calculation unit 16 corresponds to the “first pixel value calculation unit” and the “second pixel value calculation unit” of the present invention, and the region of interest setting unit 17 performs the “first region of interest setting” of the present invention. Means "and" second region of interest setting means ".

  In the present embodiment, the morphological images of the subject are collected using the X-ray CT apparatus 3, but a known MRI apparatus may be used instead. When using the MRI apparatus, a plurality of gradient magnetic fields are applied to the subject to obtain projection data of nuclear magnetic resonance signals. Then, a nuclear magnetic resonance image is generated based on the projection data, combined with a functional image obtained by the nuclear medicine diagnostic apparatus 2 as a morphological image, and displayed on the monitor 9a of the display device 9.

[Second Embodiment]
Next, an ultrasonic therapy apparatus according to the second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a side view showing a schematic configuration of the ultrasonic therapy apparatus according to the second embodiment.

  The ultrasonic therapy apparatus according to the second embodiment has substantially the same configuration as the ultrasonic therapy apparatus 1 according to the first embodiment. However, during imaging by the nuclear medicine diagnosis apparatus 2, the bed top plate 51 is The acoustic medium 42 filled in the groove 55 is drained.

  In the ultrasonic therapy apparatus 1 according to the first embodiment, the acoustic medium 42 is still filled in the groove portion 55 of the bed top plate 51, and the state remains as it is even when photographing by the nuclear medicine diagnostic apparatus 2. Keep. Therefore, as described above, the radiation detector 21A arranged in the region shielded by the acoustic medium 42 does not detect γ rays. What improved this is equivalent to the ultrasonic therapy apparatus concerning this 2nd Embodiment.

  A hole (not shown) is formed in the bottom of the groove portion 55 of the couch top plate 51, and a water pipe (not shown) is installed in the hole to drain the acoustic medium 42 filled in the groove portion 55. When photographing with the nuclear medicine diagnostic apparatus 2, the acoustic medium 42 is drained by the water distribution pipe, and the ultrasonic applicator 41 is moved to the outside of the nuclear medicine diagnostic apparatus 2 by the holding member 42. The holes and water distribution pipes formed in the groove 55 correspond to the “acoustic medium discharging means” of the present invention.

  On the other hand, when performing treatment by irradiating the affected part with focused high-power ultrasound by the ultrasonic treatment unit 4, the acoustic medium 42 is supplied to the groove part 53 through the water pipe, and the focused strong ultrasound is irradiated. In this way, by draining or filling the acoustic medium 2 in accordance with the imaging timing of the nuclear medicine diagnostic apparatus 2, it is possible to perform imaging with the nuclear medicine diagnostic apparatus 2 without attenuating γ rays. This makes it possible to detect γ-rays using all the radiation detectors 21 and to detect γ-rays in all directions by a coincidence method. In this case, the nuclear medicine diagnosis apparatus 2 functions as a PET apparatus. In the present embodiment, the collection of the functional image and the cauterization by the ultrasonic treatment unit 4 cannot be performed at the same time, but the affected part can be monitored and the cautery can be performed by one apparatus.

Moreover, a collimator may be installed in the radiation detector 21 and the nuclear medicine diagnostic apparatus 2 may be used as a SPECT apparatus. In this case, a radiopharmaceutical containing a substance having the property of accumulating in a specific tumor or molecule and a single photon emitting nuclide ( ⁹⁹ Tc, ⁶⁷ Ga, ²⁰¹ Ti, etc.) is administered to the subject, and γ generated from the radiopharmaceutical The line is detected by all the radiation detectors 21, the position where the radiopharmaceutical is distributed is specified, and a SPECT image is generated. Even with such a device configuration, it is possible to perform monitoring of the affected area and cauterization with a single device.

[Third Embodiment]
Next, an ultrasonic therapy apparatus according to the third embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a side view showing a schematic configuration of an ultrasonic therapy apparatus according to the third embodiment. FIG. 9 is a cross-sectional view taken along line BB ′ in FIG.

  The ultrasonic therapy apparatus according to the third embodiment has substantially the same configuration as the ultrasonic therapy apparatus 1 according to the first embodiment, but the ultrasonic therapy unit 4 including the ultrasonic applicator 41 is used. Configuration and location are different. The configurations of the nuclear medicine diagnostic apparatus 2 and the X-ray CT apparatus 3 are the same as those of the ultrasonic therapy apparatus 1 according to the first embodiment. In the ultrasonic therapy apparatus 1 according to the first embodiment, the ultrasonic therapy unit 4 is installed in the groove 55 formed in the bed top plate 51, but the ultrasonic therapy apparatus according to the third embodiment. In FIG. 1, the ultrasonic applicator 41 is held by an arm 49 extending from the side surface of the nuclear medicine diagnostic apparatus 2 and is movable in the horizontal and vertical directions.

  In addition to the ultrasonic vibrator, the ultrasonic applicator 41 is provided with a water bag 48 for holding the acoustic medium 42, and the acoustic medium 42 is stored in the water bag 48. Furthermore, an ultrasonic probe for ultrasonic diagnostic imaging may be provided as in the first embodiment. Further, the contact pressure between the subject and the ultrasonic applicator may be detected by a pressure sensor provided in the water bag 48 and adjusted so as to obtain an appropriate pressure by adjusting the loading and unloading of the acoustic medium. .

  The arm 49 that holds the ultrasonic applicator 41 is rotatably connected to the arm members 49a, 49b, and 49c by joint members 49d, 49e, and 49f, and one end of the arm member 49c is connected via the joint member 49f. It is installed on the side of the nuclear medicine diagnostic apparatus 2. The arm member 49a is rotatable in the vertical direction around the joint member 49d, and the arm member 49b is rotatable in the vertical direction around the joint member 49e. Further, the arm member 49c can rotate in the vertical and horizontal directions around the joint member 49f. An ultrasonic applicator 41 is installed at the tip of the arm member 49a. By being held by the arm 49 in this way, the ultrasonic applicator 41 can move in the vertical direction, the horizontal direction, and the front-back direction.

  The arm 49 is connected to an arm control unit (not shown), and when the operator operates the operation unit 7, the ultrasonic applicator 41 installed at the tip of the arm 49 is moved via the control unit 6. be able to.

  Next, the arrangement of the radiation detectors 21 in the nuclear medicine diagnosis apparatus 2 will be described with reference to FIG. As in the first embodiment, the cross section of the nuclear medicine diagnostic apparatus 2 shown in FIG. D is divided into four. These two imaginary lines pass through the center point O and are set so as to pass through in contact with the water bag 48 installed in the ultrasonic applicator 41.

  Of the radiation detectors 21 arranged in the regions A to D, the radiation detector 21A arranged in the region A does not detect γ rays. An ultrasonic applicator 41 including an acoustic medium 42 filled in a water bag 48 is disposed between the radiation detector 21A disposed in the region A and the affected part of the subject, and is emitted from the affected part. This is because the γ rays are attenuated by the acoustic medium 42.

  Therefore, as in the first embodiment, since the arrangement position of the ultrasonic applicator is known in advance, γ rays are detected by the radiation detectors 21B to 21D arranged in the area other than the area A. When the nuclear medicine diagnosis apparatus 2 is a PET apparatus, the detected γ-ray detection signal is processed by the counting apparatus 23 by the coincidence counting method, and the count value and the position information of the detection point are output to the reconstruction processing unit 25. Is done. The regeneration processing unit 25 generates functional image data based on these signals. Thus, the functional image data is generated by selecting the radiation detector 21 that detects γ-rays based on the relationship between the position of the ultrasonic applicator 41 and the position of the center point O.

  The operation of the ultrasonic treatment apparatus according to the third embodiment is the same as that of the ultrasonic treatment apparatus 1 according to the first embodiment, and the X-ray CT is performed by moving the bed top 51 horizontally in the right direction. The apparatus 3 is moved from the apparatus 3 to the nuclear medicine diagnosis apparatus 2, and the X-ray CT image data and the functional image data are combined to generate combined tomographic image data, and the combined tomographic image is displayed on the monitor 9 a of the display device 9. Then, focused ultrasonic waves are applied to the affected part of the subject by the ultrasonic applicator 41.

[Fourth Embodiment]
Next, an ultrasonic therapy apparatus according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a side view showing a schematic configuration of the ultrasonic therapy apparatus according to the fourth embodiment.

  The ultrasonic therapy apparatus according to the fourth embodiment has the same configuration as the ultrasonic therapy apparatus according to the third embodiment, but the operation is different. In the ultrasonic therapy apparatus according to the third embodiment, the ultrasonic applicator 41 is inserted into the hole 10 of the nuclear medicine diagnostic apparatus 2 even during imaging by the nuclear medicine diagnostic apparatus 2. In such an ultrasonic therapy apparatus, the ultrasonic applicator 41 is moved to the outside of the hole 10 of the nuclear medicine diagnostic apparatus 2 when photographing by the nuclear medicine diagnostic apparatus 2. The operator operates the operation unit 7 to drive the arm 49 to make the ultrasonic applicator 41 stand by outside the nuclear medicine diagnostic apparatus 2. Further, when performing treatment, the arm 49 is driven to move the ultrasonic applicator 41 to the upper part of the affected area and irradiate focused intense ultrasonic waves.

  Thus, by moving the ultrasonic applicator 41 to the outside or the inside of the nuclear medicine diagnostic apparatus 2 according to the imaging timing of the nuclear medicine diagnostic apparatus 2, the γ rays are attenuated as in the second embodiment. It is possible to take an image with the nuclear medicine diagnostic apparatus 2 without any problem. This makes it possible to detect γ-rays using all the radiation detectors 21 and to detect γ-rays in all directions by a coincidence method. In the present embodiment, the collection of functional images and the cauterization by the ultrasonic treatment unit 4 cannot be performed at the same time, but the affected part can be monitored and cauterized by one apparatus.

1 is a side view showing a schematic configuration of an ultrasonic therapy apparatus according to a first embodiment of the present invention. 1 is a block diagram showing a schematic configuration of an ultrasonic therapy apparatus according to a first embodiment of the present invention. It is sectional drawing in line segment A-A 'shown in FIG. It is a figure which shows the synthesized image obtained by the ultrasonic therapy apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the synthetic | combination image obtained by the ultrasonic therapy apparatus which concerns on 1st Embodiment of this invention, and the spectrum of the pixel value in an affected part. It is a figure which shows the composite image obtained by the ultrasonic therapy apparatus which concerns on 1st Embodiment of this invention, and the spectrum of the pixel value in an affected part. It is a side view which shows schematic structure of the ultrasonic treatment apparatus which concerns on 2nd Embodiment of this invention. It is a side view which shows schematic structure of the ultrasonic treatment apparatus which concerns on 3rd Embodiment of this invention. It is sectional drawing in line segment B-B 'shown in FIG. It is a side view which shows schematic structure of the ultrasonic therapy apparatus which concerns on 4th Embodiment of this invention. It is sectional drawing which shows the collimator with a rotation mechanism in the ultrasonic therapy apparatus which combined the SPECT apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic therapy apparatus 2 Nuclear medicine diagnostic apparatus 3 X-ray CT apparatus 4 Ultrasonic treatment part 5 Bed apparatus 6 Control part 7 Operation part 8 Image composition part 9 Display apparatus

Claims (10)

An imaging device that generates a first tomographic image by irradiating a subject with X-rays or ultrasonic waves, or applying a gradient magnetic field and a high-frequency magnetic field;
A plurality of radiation detectors are installed surrounding the subject, and a second tomogram of the subject is detected by detecting radiation emitted from a radiopharmaceutical administered to the subject with the plurality of radiation detectors. A nuclear medicine diagnostic device for generating
A display device for displaying a combined tomogram obtained by combining the first tomogram and the second tomogram;
An ultrasonic applicator installed in an area surrounded by the plurality of radiation detectors, having an acoustic medium with the subject, and irradiating focused ultrasound on the affected area of the subject;
An ultrasonic therapy apparatus comprising:   The radiation detector is disposed over the entire circumference so as to surround the ultrasonic applicator, and detects radiation by a detector disposed in a region other than the region shielded by the ultrasonic applicator. The ultrasonic therapy apparatus according to claim 1. The ultrasonic applicator is installed freely in and out of the area surrounded by the radiation detector,
The said ultrasonic applicator is moved to the outer side of the area | region enclosed by the said radiation detection apparatus, when detecting a radiation with the radiation detector of the said nuclear medicine diagnostic apparatus, The Claim 1 or Claim characterized by the above-mentioned. The ultrasonic therapy apparatus according to any one of 2 above. It further has a bed on which a subject is placed, in which a groove is formed,
The radiation detector is placed around the bed;
The ultrasonic therapy apparatus according to claim 1, wherein the acoustic medium is filled in the groove, and the ultrasonic applicator is installed in the acoustic medium. Acoustic medium discharging means installed in a groove formed in the bed and discharging the acoustic medium to the outside of the groove;
Moving means for moving the ultrasonic applicator to the outside of the region surrounded by the radiation detector along the groove;
The ultrasonic therapeutic apparatus according to claim 4, further comprising: First region-of-interest setting means for setting a region of interest consisting of a line segment of a predetermined length so as to cross the second tomographic image displayed on the display device;
First pixel value calculating means for sequentially calculating pixel values of the second tomographic image on the line segment set by the first region of interest setting means;
The ultrasonic treatment apparatus according to claim 1, wherein the display device displays a pixel value calculated by the first pixel value calculation unit. Second region-of-interest setting means for setting a region of interest having a predetermined area so as to include a second tomographic image displayed on the display device;
An average pixel value or total pixel value of the second tomographic image in the region of interest set by the second region of interest setting means is sequentially calculated, and the average pixel value or the total pixel value per unit time A second pixel value calculating means for calculating a change amount and comparing the change amount per unit time with a preset value;
The ultrasonic therapy apparatus according to claim 1, further comprising: Marker setting means for setting a marker indicating a position to irradiate focused ultrasound,
The display device displays a combined tomographic image obtained by combining the first tomographic image and the second tomographic image, and displays the set marker. The ultrasonic therapy apparatus in any one of. It further has a position detecting means for detecting the position of the ultrasonic applicator,
The display device displays a combined tomographic image obtained by combining the first tomographic image and the second tomographic image, and the ultrasonic wave is displayed on the combined tomographic image based on the position detected by the position detecting unit. The ultrasonic therapy apparatus according to claim 1, wherein an image of an applicator and a propagation path of a focused ultrasonic wave irradiated from the ultrasonic applicator are displayed. In the imaging apparatus, an X-ray source and an X-ray detector are installed across the subject, and the X-ray detector detects X-rays irradiated from the X-ray source and transmitted through the subject. An X-ray CT apparatus for generating a first tomographic image of the subject;
An MRI apparatus that applies a plurality of gradient magnetic fields to the subject and generates a first tomographic image composed of a nuclear magnetic resonance image based on projection data of a nuclear magnetic resonance signal obtained as a result,
Alternatively, a first tomographic image including an ultrasonic diagnostic image is obtained by irradiating the subject with ultrasonic waves using an ultrasonic probe installed in the ultrasonic applicator and receiving a reflected wave from the subject. The ultrasonic therapeutic apparatus according to claim 1, wherein the ultrasonic therapeutic apparatus is any one of an ultrasonic diagnostic apparatus that generates a signal.

Images