JP4012177B2 - Ultrasonic therapy device - Google Patents

Description

  The present invention relates to an ultrasonic treatment apparatus for treating a tumor in a living body using ultrasonic waves.

(1) In recent years, the flow of minimally invasive treatment called MIT (Minimally Invasive Treatment) has attracted attention in various medical fields. One example of this is the practical application of a stone crushing device that irradiates high-power ultrasound from outside the body and treats stones in a non-invasive manner, which has greatly changed the treatment of urinary stones. . As a method for generating high-intensity ultrasonic waves used in this calculus breaking device, an underwater discharge method, an electromagnetic induction method, a micro explosion method, a piezo method, and the like are known. Among these, the piezo method that generates cooperative ultrasonic waves by using a piezo element is particularly powerful as described in JP-A-60-145131, USP-4526168, etc. Attention has been focused on the advantages such as the ability to arbitrarily control the sonic pressure and the ability to arbitrarily control the focal position by phase controlling the drive voltages applied to a plurality of piezo elements.

  On the other hand, MIT is one keyword in the field of tumor treatment. Especially in the case of malignant neoplasms, so-called cancers, because many of the treatments depend on surgical operations, the functions and appearances of the organs are often greatly impaired, and even if life is prolonged. Since a large burden remains for the patient, development of a treatment method and a treatment apparatus with less invasiveness considering QOL (Quality Of Life) is strongly desired.

  In this trend, hyperthermia therapy has been attracting attention as one of the cancer treatment techniques. This is a treatment method in which only cancer cells are selectively killed by heating and maintaining the affected area at 42.5 ° C. or higher by utilizing the difference in heat sensitivity between tumor tissue and normal tissue. As a method for heating, a method using electromagnetic waves such as microwaves has been preceded, but it is difficult to selectively heat a deep tumor due to the electrical characteristics of the living body, and the depth is 5 cm or more. Good treatment results are not expected for these tumors. Therefore, a method of using ultrasonic energy with high convergence and high penetration is considered for the treatment of deep tumors (Japanese Patent Laid-Open No. 61-13955).

In addition, this warming treatment method is further advanced, the ultrasonic wave generated from the piezo element is focused on the affected part, the tumor part is heated to 80 ° C. or more, and the tumor tissue is instantly denatured by protein degeneration or heat degeneration. The law has also been reported (G. Vallancien et.al .: Progress in Uro. 1991, 1,84-88, JP-A-61-13955, Japanese Patent Application No. 3-306106, etc.). In this treatment method, since a very intense ultrasonic wave is applied to a limited area near the focal point, unlike conventional hyperthermia, it is necessary to irradiate the entire area where the tumor exists while scanning the focal point. There is. In particular, when high-intensity ultrasonic waves of several thousand W / cm ² are irradiated, it is considered that a change in acoustic characteristics due to cavitation generated due to irradiation and thermal denaturation of the affected part becomes a serious problem. In the area where cavitation has occurred, heat generation due to ultrasonic waves is likely to occur. A fever may be triggered and sometimes cause side effects.

  In order to solve this problem, there has been proposed a method for controlling so as not to continuously irradiate high-power ultrasonic waves to adjacent parts (Japanese Patent Application No. 4-43603). However, in this method, there has been no description on how to control irradiation when it is necessary to irradiate powerful ultrasonic waves to adjacent parts.

  (2) In addition, therapies that irradiate cancer with a powerful pulse-like ultrasonic wave that crushes stones, instead of fever caused by ultrasonic waves, and necrotize the cells with the mechanical force are also being studied ( For example, Hoshi, S. et al .: J. Urology, Vol. 146: 439, 1991.). By the way, using these ultrasonic treatment devices can reduce the burden on the patient because it is not necessary to open the stomach, but on the other hand, since the affected part cannot be directly observed, A means for obtaining the position of the treatment target is required.

  In the conventional ultrasonic therapy apparatus, there is a method using an ultrasonic tomographic image when positioning the focus of high-intensity ultrasonic waves, but the tumor to be treated often exhibits a three-dimensionally complicated shape, It is very difficult to treat the entire tumor uniformly with a two-dimensional image. Therefore, a combination with a three-dimensional image using ultrasonic waves has been proposed as disclosed in Japanese Patent Application Laid-Open No. 61-209643. However, with ultrasonic waves, the back of the aerated organs such as bones and lungs cannot be seen, and ultrasonic information is displayed. Even if it is based, an accurate three-dimensional image cannot be obtained. Further, in this conventional example, the relative position between the focal point and the treatment site is simply confirmed, there is no means for judging the effect of treatment, and the continuation / end of treatment cannot be determined until several weeks to several months later.

  Therefore, a method of using the above-described ultrasonic therapy apparatus in combination with MRI (Magnetic Resonance Imaging System) or X-ray CT that collects in-vivo three-dimensional information and displays an in-vivo image has been considered. For example, Japanese Patent Laid-Open No. 2-161434 describes an apparatus for performing treatment such as puncture based on an MRI image.

  Further, in Japanese Patent Application No. 5-228744, in order to prevent erroneous irradiation of a normal tissue and perform reliable treatment in an ultrasonic treatment apparatus, the affected area is surely heated to a high temperature using an image diagnostic apparatus, It describes the real-time monitoring that normal tissue is not overheated and the measurement of the warming position. For example, non-invasive temperature measurement is possible using the temperature dependence of MRI chemical shift (Y. Ishihara et al .: Proc. 11th Ann. SMRM Meeting, 4803, 1992). Here, the amount of change in chemical shift due to temperature change is measured using a phase mapping method in which the static magnetic field distribution is replaced with a phase distribution.

  It is the movement of the treatment target that is most problematic when such warming treatment is performed. In the living body, there are inevitable movements such as breathing, pulsation and the like, and this causes the following problems.

  First, when the treatment target moves, ultrasonic irradiation is performed on a site different from the treatment planned site set in the treatment plan before the treatment, and the normal tissue is damaged. Secondly, if the phase mapping method is used when the above-described temperature measurement is performed, it is necessary to acquire a reference image before heating and calculate a difference for each image pixel. Further, since the heat-denatured portion due to heating changes the relaxation time, the denatured portion can be imaged and used for confirmation of the treatment effect (Japanese Patent Application No. 05-228744). The part can be observed clearly. However, when the difference is taken as described above, an error is generated because a difference between different pixels is calculated when the treatment target moves between imaging.

  In order to reduce these effects, it is necessary to detect the target motion vector. Thereby, the irradiation position of the treatment energy can be changed with respect to the movement to follow the movement, and an error can be reduced by performing the difference processing after correcting the image for which the difference processing is performed. Japanese Patent Laid-Open No. Sho 62-217976 discloses that an ultrasonic temperature distribution measuring device adds a perturbation to an imaging probe and moves the imaging surface in a direction with a large correlation coefficient, thereby tracking the difference in the same region of interest. An apparatus for calculating is described.

  Regarding the motion vector detection method, several methods are considered in the field of image processing. Methods using image data as they are, such as pattern matching method and gradient method, are common (essentially equivalent to the method of calculating correlation coefficient by adding perturbation), but the image is subjected to Fourier transform and spatial frequency domain The motion vector can also be calculated by calculating the inverse Fourier transform of the product or the quotient, and calculating the cross-correlation function or impulse response (Takahiko Fukiuki, “Multidimensional signal processing of TV images”, Nikkan Kogyo Shimbun) .

  However, if a general pattern matching method or the like is used to detect the motion, the images are gradually shifted and the least square error between the images is calculated each time. In particular, in the case of three dimensions, until the motion vector is calculated. Requires a huge amount of computation. As described above, motion can also be detected by calculating a correlation coefficient. However, since each correlation coefficient is calculated by giving a three-dimensional perturbation, it takes time to detect a motion vector. Even when the cross-correlation function is calculated, if it is calculated as it is in real time, a two-dimensional convolution integral is calculated, which again takes time. However, in order to follow the movement of the object, real-time movement information is required.

  (3) Furthermore, in Japanese Patent Application No. 05-228744, the relaxation times T1 and T2 change due to the thermal denaturation of the tissue, so that the heat-denatured portion can be depicted with these enhanced images and the therapeutic effect can be confirmed. It is stated.

  (4) In recent years, many MRI systems having open-type magnets that can be easily accessed from the outside have been announced, and the use of this as a monitor MRI for surgery or the like is described in JP-A-4-31446. ing. In such MRI, the surgeon can perform treatment while monitoring with MRI.

  On the other hand, it is also possible to excite only one point at an arbitrary position by performing selective excitation in the x, y, and z directions in MRI. In addition, a technique for performing excitation in an arbitrary shape at an arbitrary site by one excitation has been reported (C.J. Hardy, and H.E.Cline, Journal of Magnetic Resonance, vol.82, pp.647-654, 1989). Using this, only the NMR signal at a certain position can be obtained. It is also possible to perform local excitation three-dimensionally with a single excitation (J. Pauly et al .: “Three-Dimensional π Pulse”, Proc. 10th Ann. SMRM Meeting, 493, 1991). It is also considered that these are applied to a temperature monitoring sequence for heat treatment using ultrasonic waves or the like (US Pat. No. 5,307,812).

  In addition, in experiments using meat pieces for heat treatment using focused ultrasound, it was found that if the irradiation time was lengthened, the denatured area expanded toward the front side along the irradiation axis, and the heated area did not necessarily coincide with the focal point. (Fujimoto et al., Journal of the ME Society of Japan JJME, vol.32 Suppl., Pp.125). Therefore, temperature monitoring during treatment becomes very important.

  (5) Further, as a means for monitoring a treatment site in a patient, for example, in a stone crushing device, as proposed in Japanese Patent Laid-Open No. 63-5736, non-powerful ultrasonic pulses (shock waves) for crushing stones are not used. There is known a device that emits a shock wave only when a focal point coincides with a calculus by analyzing a reflection signal from the calculus by irradiating a weak ultrasonic wave for calculus exploration at the time of irradiation. In addition, as described in Japanese Patent Application Laid-Open No. 4-43603, there is proposed a monitoring system using MRI, CT or an ultrasonic diagnostic apparatus for a warming treatment apparatus using high intensity ultrasound. However, in the heating device using the ultrasonic diagnostic device as the monitoring device, there is a problem that the ultrasonic waves for treatment affect the monitoring, and real-time monitoring during treatment cannot be performed.

  To solve this problem, as proposed in Japanese Patent Application No. 60-241436, therapeutic ultrasound is used when the in-vivo image is not constructed so that the in-vivo image does not affect the in-vivo image. Devices for irradiating are known. In addition, in an ultrasonic heating apparatus that performs monitoring using MRI or CT, a dedicated monitoring apparatus must be prepared separately from the treatment energy source, which increases the installation space of the apparatus and increases the cost burden. There was a drawback.

  In response to the above problems, as disclosed in JP-A-5-194359, a therapeutic ultrasonic energy generation source in which a lithotripsy piezo element and a piezo element for heating / heating treatment are integrated is proposed, An apparatus using a piezo element for pulverizing stones as a weak ultrasonic wave generation source for investigation of a treatment area is known during heating / heating treatment.

  (6) By the way, in the ultrasonic therapy apparatus that focuses the ultrasonic wave from outside the body as described above, the therapeutic ultrasonic wave is reflected when treating a part where the bone is on the upper part, for example, the brain or the liver. For this reason, it has been difficult to irradiate the affected area with sufficient energy. Further, when treating a very deep site near the center of the body, the frequency has to be lowered in order to increase the progress of the ultrasonic wave, and there is a problem that the focal spot size becomes large. Here, it is known that the size W in the azimuth direction of the ultrasonic focus is proportional to R / A * f (A: transducer diameter, R: transducer curvature, f: ultrasonic frequency), that is, inversely proportional to the frequency f. ing.

  In order to solve such problems, in recent years, attempts have been made to treat a body cavity with a transducer for irradiating therapeutic ultrasound. For example, in NTSanghvi et al. Noninvasive transrectal ultrasound device for prostate tissue visualization and tisue ablation in the focal zone using high intensity focused beam., J Ultrasound Med., 1991; 10: 104-109, a transducer is inserted into the rectum. Attempts have been reported to treat the prostatically enlarged prostate.

  (7) In the above-described tumor treatment apparatus, an ultrasonic tomographic image is used when the focal point is positioned. However, a tumor to be treated often has a complicated three-dimensional shape. It is very difficult to treat the entire tumor evenly. Therefore, a combination with a three-dimensional image using ultrasonic waves has been proposed as described in Japanese Patent Application Laid-Open No. 61-209643. However, the ultrasonic waves show the back of aerobic organs such as bones and lungs. In addition, an accurate three-dimensional image could not be obtained based on ultrasonic information.

  Moreover, in the conventional example, the relative position between the focal point and the treatment site is simply confirmed, there is no means for judging the effect of treatment, and the continuation / end of treatment cannot be determined until several weeks to several months later. Therefore, a method using MRI that collects in-vivo three-dimensional information and displays an in-vivo image as CT can be considered. However, in MRI, image reconstruction is not necessarily performed in real time. For this reason, it is impossible to capture a fast movement due to the patient's breathing or body movement. In order to prevent erroneous irradiation due to this movement, an ultrasonic imaging apparatus may be used in combination with CT (Japanese Patent Laid-Open No. 5-300910). At this time, by providing a means for obtaining a relative position between the ultrasonic probe for obtaining a tomographic image and the focus of the therapeutic ultrasonic wave, the focal position is displayed on the ultrasonic image, or two-dimensional or three-dimensional obtained by CT. The position of the ultrasonic tomographic image currently displayed on the three-dimensional in-vivo image is shown, and the ultrasonic tomographic image can be used in accordance with the previously set treatment plan.

Furthermore, it has been reported that tissue degeneration due to heat can be confirmed in MRI T2 images (Ferenc A. Jolesz et al .: MR Imaging of Laser-Tissue Interactions). Therefore, by observing the difference between these two MRI images before and after treatment, it is possible to determine the biological action / therapeutic effect of this treatment, and it is possible to treat while confirming the untreated part. A therapeutic effect can be secured.
JP 60-145131 A US Pat. No. 4,526,168 JP-A 61-13955 Japanese Patent Application No. 3-306106 Japanese Patent Application No. 4-43603 JP-A 61-209634 JP-A-2-161434 Japanese Patent Application No. 5-228744 Japanese Patent Application No. 05-228744 JP-A-4-31446 US Pat. No. 5,307,812 JP 63-5736 A JP-A-4-43603 Japanese Patent Application No. 60-241436 JP-A-5-194359 JP-A 61-209634 Japanese Patent Laid-Open No. 5-300910 Fukiuki Takahiko, “Multidimensional signal processing of TV images”, Nikkan Kogyo Shimbun Fujimoto et al., Journal of the Japan Society of ME, JJME, vol.32 Suppl., Pp.125 NTSanghvi et al., Noninvasive transrectal ultrasound device for prostate tissue visualization and tisue ablation in the focal zone using high intensity focused beam., J Ultrasound Med., 1991; 10: 104-109

Erroneous irradiation preventing functions described in JP Gantaira 5-228744 is pre-check function, the actual temperature monitor during treatment irradiation was not performed. However, the living body has movements such as respiratory movement and body movement, and there is a possibility that the living body may move during treatment irradiation. In such a case, temperature measurement is important as a check for abnormal irradiation conditions. However, in heat treatment, since the focal part is instantaneously heated to a high temperature, the temperature measurement requires a considerably high time follow-up property (real-time property). On the other hand, since the energy irradiation position is known in advance, the measurement range can be limited, and since the temperature distribution is known to be gentle, it is sufficient that the spatial resolution as high as that of a normal image cannot be obtained. In addition to temperature, it is necessary to obtain data indicating therapeutic effects with high time resolution, and a measurement method that gives top priority to time resolution is required.

  However, when such temperature measurement is performed, if the distribution is to be taken as a distribution, for example, in a normal spin echo sequence, the time required for one excitation (repetition time) is multiplied by the number of encodings in order to capture one image. is necessary. For example, if the repetition time is 2 seconds and the number of encoding times is 128, about 5 minutes are required. On the other hand, high-speed imaging such as field echo and ultra-high-speed imaging such as an echo planer have been devised. However, field echo requires several seconds for imaging, and ultra-high-speed imaging requires several hundreds of milliseconds. Even if imaging is performed at a high speed, a certain amount of time is required for the subsequent reconstruction process. As a result, a time lag of about several seconds occurs, and accurate temperature control becomes impossible. In heat treatment, a high temperature is instantaneously reached, so a time lag of several seconds is dangerous.

The purpose of the present invention is to provide accurate and secure therapy system energy irradiation can check during actual treatment whether it is normal by obtaining temperature information of the specific portion only in real time during the treatment irradiation .

The present invention provides a magnetic resonance diagnostic apparatus for collecting image information in a subject and recognizing a treatment target site in the subject, and heat denaturation by irradiating the treatment target site with irradiation of the treatment target site. The therapeutic energy irradiation means for performing treatment, the measurement part setting means capable of arbitrarily setting the temperature measurement part during the treatment energy irradiation by the therapeutic energy irradiation means, and the measurement part setting means When the temperature measurement part shows a predetermined temperature rise based on the temperature information acquired by means for acquiring temperature information using local excitation by the magnetic resonance diagnostic apparatus and the temperature information acquired by the means When the therapeutic energy irradiation means continues the therapeutic energy irradiation and the temperature measurement portion does not show the predetermined temperature rise, the therapeutic energy is emitted. Characterized by a control means for controlling so as to stop the irradiation of the therapeutic energy at the Energy irradiation means.

(Function)
When performing pressurized heat treatment, the operator will determine the site most notable on the treatment, it is inputted to the control unit. Specifically, several points are selected, such as the center of the treatment target where the temperature must rise sufficiently and surrounding important tissues where the temperature should not rise. Then, during the treatment energy irradiation, the magnetic resonance diagnostic apparatus excites the above-mentioned several points by the local excitation method, measures temperature information based on the excitation, and displays it on the screen. Here, since the measurement points are limited and processing such as reconstruction is simplified, the measurement time is greatly shortened. Further, by not displaying a large amount of measurement data, only necessary information can be provided without causing unnecessary confusion to the operator.

According to the present invention, in a treatment apparatus using a magnetic resonance diagnostic apparatus, it becomes possible to perform temperature measurement on a necessary point of a temperature monitor obtained in advance using a local excitation method in real time, and an abnormality can be detected during irradiation. A safe treatment device that can be discovered can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
( First Reference Example )
FIG. 1 is a block diagram showing the configuration of the first reference example . The therapeutic applicator 101 includes a piezo element (group) 102 that generates high-power ultrasonic waves, a coupling solution 104 that guides high-power ultrasonic waves to a patient 103, and a coupling film 105. The piezo element group 102 includes a plurality of piezo elements that irradiate a treatment site with therapeutic ultrasonic waves as an annular array or a linear array, for example. In addition, you may make it irradiate a treatment site | part with the powerful ultrasonic wave for a treatment using a single spherical shell-shaped piezoelectric element. Usually, degassed water is used for the coupling solution 104.

  At the time of treatment, the patient 103 is first placed on a bed, and the patient 103 is fixed at a predetermined position by the table moving device 134. Then, the applicator 101 is placed on the body surface of the patient 103 through the work hole 135, and the coupling film 105 is brought into contact with the skin by an ultrasonic jelly or the like (not shown). Based on the drive phase information from the system controller 119, the phase control circuit 136 controls the drive circuit 109 with a plurality of timing signals each given a predetermined delay, and the drive circuit 109 controls each piezo element of the piezo element group 102. Is driven with a predetermined phase relationship, and a high-power ultrasonic wave for treatment is irradiated toward the focal point 106. By such drive phase control, the focal point 106 of the powerful ultrasonic wave can be set at an arbitrary place in three dimensions. This principle is described in USP-4,526,168, for example.

  At this time, the applicator position detection device 110 detects the position information of the applicator 101 from the signal from the mechanical arm 111 that movably supports the applicator 101, and sends the position information data to the system controller 119. Based on the position information data and the drive phase information, the system controller 119 displays the focal point 106 and the ultrasonic wave incident path for treatment on the CRT display 117 so as to be superimposed on the body morphological image information.

Here, in this reference example , MRI is used as an image diagnostic apparatus. That is, the system controller 119 activates the gradient magnetic field power supply 132 and the transmission / reception circuit 133 in accordance with a predetermined sequence (for example, T2-weighted imaging method) instructed from the console 120, and stores the multi-plane image information of the patient 103 on a memory (not shown). To do. The three-dimensional information on the memory is displayed on the CRT display 117 by the system controller 119.

  Further, the system controller 119 extracts the affected area from the three-dimensional image information obtained prior to the treatment, and slices the affected area according to a predetermined thickness (for example, the ultrasonic focal spot size in the depth direction). Then, each of the plurality of sections obtained by the slice is divided and displayed in a plurality of partial regions (hereinafter referred to as voxels) determined in advance by the focal spot size.

  Further, the water treatment controlled by the system controller 119 in order to keep the degree of deaeration of the coupling solution (deaerated water) 104 in the applicator 101 constant and prevent the body surface and the piezo element group 102 from generating heat. The circuit 121 performs degassing processing and cooling of the coupling solution 104.

FIG. 2 is a diagram for explaining the irradiation procedure of therapeutic high-intensity ultrasonic waves in each section in one slice. The treatment method in this reference example is a method of applying a very strong ultrasonic wave to a limited area near the focal point, and performing ablation all over while scanning the focal point 106 in the tumor-existing region (the treatment site) 107. It is. In particular, when irradiating a very strong ultrasonic wave of 1 k to 100 kW / cm ^{2, it} is considered that cavitation caused by the irradiation and a change in acoustic characteristics due to heat denaturation of the affected area are serious problems. In the area where cavitation has occurred, heat generation due to ultrasonic waves is likely to occur. A fever may be triggered and sometimes cause side effects. In order to solve this problem, it is necessary to set the temporal and spatial intervals of ultrasonic irradiation and to irradiate the adjacent site after the cavitation has sufficiently disappeared. For this purpose, this reference example employs the following intense ultrasonic irradiation procedure.

  (Procedure 1): The irradiation regions that are continuous or close in time are irradiated with ultrasonic waves separated by a predetermined distance (r) or more as shown in FIG.

  Here, the predetermined distance is a distance that is not affected by the cavitation generated by the last irradiation. For example, when the focal size (intensity distribution) in the azimuth direction is 2 mm, the distance is 5 times that of 10 mm or more. It is considered that the position is hardly affected by the last irradiation. The distance between two areas here refers to the distance between the centers (centers of gravity) of the respective areas.

  (Procedure 2): When there is no area corresponding to the procedure 1, irradiation is performed on the farthest from the starting point in all the areas.

  (Procedure 3): Irradiation is performed with a predetermined time interval or more between irradiation regions that are adjacent (continuous) or close in position. This is shown in FIG.

  Here, the predetermined time period is a time period until the cavitation generated in the focal region is almost disappeared when irradiation with high intensity ultrasonic waves is performed. Specifically, although it depends on the medium and the state of the body, it has been found that an interval of 5 to 30 seconds or more is necessary from the results of animal experiments conducted by us.

  The actual irradiation procedure will be described with reference to an example. In the case of FIG. 2 (b1), the region 1 and the region 5 are separated from each other by time t as shown in FIG. 2 (b2). When the region 1 and the region 2 are adjacent to each other as in (c1), it is necessary to perform irradiation at intervals of time t or more as shown in FIG. 2 (c2). At this time, the region 3 is also adjacent to the region 1, but there is no problem because the irradiation timings of the region 1 and the region 3 are already separated by the time t or more. In the case of FIG. 2 (d1), the region 1 and the region 2 and the region 2 and the region 3 are separated from each other by the distance r, so that continuous irradiation is possible, but the region 1 and the region 3 are adjacent to each other. It is necessary to control the irradiation time so that the irradiation timing is more than time t.

  (Procedure 4): In the case of Procedure 2, that is, in the case of FIG. 2 (d1), the interval between ultrasonic irradiations is irradiated with a separately determined time. The separately determined time is, for example, a simple proportional calculation between the distance r capable of continuous irradiation and the distance d between the two regions, and can be determined as follows (see FIG. 2 (d2)).

t ′ = T + (t−T) (1−d / r) (seconds)
Further, the present invention is not limited to this, and it is also possible to irradiate with an interval of time t for all areas that are less than the distance that can be continuously irradiated. In this case, however, the total treatment time is slightly longer.

  FIG. 3 is a flowchart showing the above procedure. This process is executed by the system controller 119 of FIG. First, after determining the starting point of the treatment ultrasonic irradiation position, it is determined whether or not irradiation can be performed at a distance r or more from the starting point (next point) to the next irradiation point (next point). If there is, it is further checked whether there are a plurality of next point candidates (S102). If it is determined yes in S102, the point closest to the starting point is the next point, and if it is determined No, that one candidate is the next point. Then, an ultrasonic irradiation time interval between the starting point and the next point determined in S102 to S104 is set at T seconds. This corresponds to the case of FIG.

  On the other hand, when it is determined No in S101, the point farthest from the starting point is set as the next point (S105), and it is further checked whether the next point and the starting point are adjacent (S106). If it is determined No in S106, the ultrasonic irradiation time interval between the starting point and the next point is set at t ′ seconds. This corresponds to the case of FIGS. 2 (e1) and (e2).

  Furthermore, when it is determined as Yes in S106, the ultrasonic irradiation time interval between the starting point and the next point is left for t seconds. This corresponds to the case of FIGS. 2 (b1) (b2) (c1) (c2) (d1) (d2).

  If irradiation with high intensity ultrasonic waves for treatment is performed on the basis of the procedure as described above, it is possible to perform all irradiation in the shortest time or a time equivalent thereto. A flowchart of this procedure is shown in FIG.

  FIG. 4 shows another procedure of intense ultrasonic irradiation. Each section is divided into several groups in advance, and numbers are assigned sequentially from 1 to A-1, B-1, C-1,..., A-2, B-2, C-2,. It is a method of irradiating in the order. In this method, if the number of groups is set in advance so that the remaining cavitation time is t or more, continuous irradiation to adjacent places can be avoided in most cases. However, since this method is not perfect, a more reliable irradiation procedure can be realized by combining with the methods 3 and 4 described above.

( Second reference example )
FIG. 5 is a block diagram showing the configuration of the second reference example . The therapeutic applicator 101 includes a piezo element group 102 that generates high-power ultrasonic waves, a coupling solution 104 that guides high-power ultrasonic waves to the patient 103, a coupling film 105, an ultrasonic probe 8 that acquires an image of an affected area, and an ultrasonic probe. It comprises a Zθ stage 113 and an Xθ stage 114 for moving and rotating the position of the acoustic probe. The piezo element group 2 is composed of one or a plurality of elements that irradiate high-power therapeutic ultrasonic waves. At the time of treatment, the applicator 110 is placed on the body surface of the patient 103, and the coupling film 105 is brought into contact with the skin using an ultrasonic jelly (not shown). Then, after aligning the focal point 106 of the powerful ultrasonic wave with the affected part 107, the drive circuit 109 drives the piezo element group 102 and irradiates the strong ultrasonic wave toward the focal point 6.

  The applicator 101 is moved by controlling the mechanical arm 111 through the system controller 119 based on information input from the console 120 and the auxiliary input device 118 by the operator. It is also possible to scan and treat the treatment range on the affected area image acquired in advance according to a certain procedure (see Japanese Patent Application Laid-Open No. 05-49551). Here, the image of the affected area is obtained by using the ultrasonic diagnostic apparatus 115 and reconstructing a signal obtained by transmitting and receiving ultrasonic waves with the ultrasonic probe 108 as a B-mode image or a three-dimensional image with the ultrasonic diagnostic apparatus 115. Displayed on the CRT display 117.

  The ultrasonic probe 108 is moved by controlling the Zθ stage 113 and the Xθ stage 114 by the stage controller 112. Further, in order to keep the degassing degree of the coupling solution 104 in the applicator 101 constant and to prevent the body surface and the piezo element group 102 from generating heat, the water treatment circuit 121 performs degassing treatment of the coupling solution 104 and Cool down.

  Next, the moving mechanism of the applicator 101 will be described. 6A and 6B are views showing the positional relationship between the piezo element group 102 and the ultrasonic probe 108 for explaining the moving mechanism. FIG. 6A is a side view and FIG. 6B is a top view.

The feature of this reference example is that the ultrasonic image can always be monitored in real time from the same position when the focal position 106 is mechanically moved. That is, in the conventional apparatus, since the ultrasonic applicator is moved at the same time as the normal applicator is moved, it was not always possible to monitor in the same situation. On the other hand, in this reference example , when the piezo element group 102 moves from the solid line to the broken line position, the Zθ stage 113 and the Xθ stage 114 are controlled by the stage controller 12, and the position / fault direction of the probe 8 (in this figure) The piezoelectric element group 102 can be moved without changing the plane direction of the ultrasonic B-mode image. As a result, an image at the same position can be acquired even during treatment, so the position, size, and state of the tumor are confirmed in advance on the image, and the change between the image and the image during irradiation is imaged and It is possible to easily confirm how far the treatment has progressed.

  FIG. 7 shows another example of a system (applicator unit) that performs treatment by scanning the focal point 106 within the affected area 107 without changing the position / tomographic direction of the ultrasonic probe. By using the XYZ stage 122 in (a) and the Zθφ stage 123 in (b), cauterization treatment of the affected area can be performed without moving the position / tomographic direction of the ultrasonic probe 108 at all.

( Third reference example )
FIG. 8 is a block diagram showing the configuration of the third reference example , which is the same as the reference example 2 except that the piezo element group 102 has a two-dimensional array configuration. In this reference example , the focal position is scanned by controlling the drive phase of each element of the piezo element group 102 as in USP-4,526,168, for example. Also according to this reference example, without moving and rotating the ultrasonic probe 108 in the same manner as described above, it becomes possible to move the position of the focal point 106 of the strong ultrasonic waves.

Next, an image display method on the CRT display 117 during treatment in this reference example will be described with reference to FIG. First, in the ultrasonic B-mode image 126 on the left side of FIG. 9A, the affected part (tumor) 107 is displayed by being sliced substantially perpendicular to the ultrasonic wave incident direction. From the results of experiments conducted by the inventors, it has been found that the acoustic characteristics of the region thermally denatured by ultrasonic heating change greatly compared to the surrounding normal tissue, and the heat denatured region is in front of the focal point. If there is, there is a possibility that sufficient acoustic energy will not propagate after that. For this reason, it is considered necessary to proceed with irradiation in order from the back of the tumor mass during treatment. Therefore, the slice thickness is determined to be approximately the same in consideration of the focal size in the depth direction of the ultrasonic wave, and in the case of this figure, it is divided into four sections “1” to “4” from the deeper side. In addition, the irradiation order is displayed in accordance with this.

  The ultrasonic addition C mode image 127 of each section is displayed on the right side of FIG. An added C-mode image is an image obtained by adding image information of a section having a predetermined thickness, that is, a reflection signal returned from the section in the thickness direction. As a result, when the cross section is viewed as a plane, it is easy to understand intuitively, and by adding the high echo portion of the already-modified region, it can be displayed with more emphasis. In this figure, the section “3” is currently being irradiated, and this is clearly indicated. The point 125 currently irradiated in the cross section is displayed in a different color.

  In the display example of FIG. 9A, “Irradiating” is displayed next to the section being irradiated, but it is also possible to display only the section that is irradiating by changing the color of each section cross-sectional image. Further, instead of clearly indicating the irradiation point 125 with different colors, for example, a blinking display can be performed.

  In addition, as shown in FIG. 9B, in order to grasp how far the irradiation has progressed in the currently irradiated image and how many unirradiated areas exist, the already irradiated area, the unirradiated area, and the currently irradiated area. The area 125 can also be clearly displayed in different colors.

  Further, instead of displaying a B-mode image as shown in FIGS. 9A and 9B, an ultrasonic three-dimensional image is displayed as shown in FIG. By displaying the three-dimensional enlarged image 129 and its added C-mode image 127 together, it is possible to provide an image interface that is easier to understand visually. Then, it is possible to input the contour and size of the tumor using the auxiliary input device 118 such as a mouse or a light pen on the image, and proceed with the treatment based on the information.

As described above, according to the present reference example , accurate monitoring can be performed by the diagnostic imaging apparatus during the powerful ultrasonic irradiation treatment. Furthermore, the position and time control during irradiation is optimized, so side effects on unexpected parts and expansion of the heat-denatured area are suppressed, and heat denaturation can be induced accurately at the target part, making it safe and reliable. Ultrasonic heating treatment can be realized.

( 4th reference example )
FIG. 10 is a block diagram showing a configuration according to the fourth reference example . In this reference example , a magnetic resonance imaging apparatus (MRI) is used as an image diagnostic apparatus, and an ultrasonic therapy apparatus is used as a treatment apparatus.

  In FIG. 10, the static magnetic field magnet 201 is excited by the excitation power source 202 and applies a uniform static magnetic field in the z direction to the subject 203. The gradient magnetic field coil 204 is disposed in a static magnetic field magnet, is driven by a drive circuit 206 controlled by a sequence controller 205, and has magnetic fields in three directions x, y, and z orthogonal to the subject 203 on the bed 207, respectively. Gradient magnetic fields Gx, Gy, Gz whose intensity changes linearly are applied. The high frequency coil 208 is a transmission / reception coil and is disposed in the gradient magnetic field coil 204.

  Under the control of the sequence controller 205, a high frequency signal from the transmission unit 209 is applied to the high frequency coil 208 via the duplexer 210, and a high frequency magnetic field generated thereby is applied to the subject 3 in the high frequency coil 208 on the bed 207. Is done. As the high-frequency coil 208, for example, a saddle type coil, a distributed constant type coil, or a quadrature transmission coil configured using these can be used, which can generate a uniform high-frequency magnetic field in a region to be imaged of the subject 203. When the treatment target is limited and a higher S / N ratio is desired, a surface coil may be used for transmission / reception or reception. When a surface coil is used for reception, a uniform coil is used for transmission.

  A reception signal obtained by receiving a magnetic resonance signal from the subject 203 by the high-frequency coil 208 is sent to the reception unit 211 via the duplexer 210. The duplexer 210 is used to switch the high-frequency coil 208 between transmission and reception, and transmits a high-frequency signal from the transmission unit 209 to the high-frequency coil 208 during transmission, and receives a reception signal from the high-frequency coil 208 during reception. It works to lead to 211.

  The received signal is subjected to detection and band limitation by a low-pass filter, and then sent to the data collection unit 212 under the control of the sequence controller 205. The data collection unit 212 collects received signals and performs A / D conversion, and sends image reconstruction data to the electronic computer 213.

  The electronic computer 213 is controlled by the console 214, performs image reconstruction processing including two-dimensional Fourier transform on the image reconstruction data input from the reception unit 211, and also controls the sequence controller 205. The image data obtained by the electronic computer 213 is supplied to the image display 215 and displayed as an image.

  On the other hand, a piezoelectric element group (not shown) for generating focused ultrasound is arranged on the ultrasonic applicator 216, and is attached to the subject 203 with a water bag (not shown). An independent drive circuit group 217 is connected to each element of the piezo element group, and a phase control circuit group 218 is coupled to the drive circuit group 217. The drive circuit group 217 applies a voltage pulse whose intensity is determined by the potential of the power supply 219 to each element of the piezoelectric element group in response to a trigger from the phase control circuit group 218. The power supply 219 and the phase control circuit group 218 are controlled by the electronic computer 213. It is well known that the position of the focal point can be electronically moved three-dimensionally by controlling the drive phase of each element when transmitting ultrasonic waves using a piezo element (for example, US Pat. No. 4,526). , 168). Accordingly, by generating a delay pulse so as to focus on the treatment site, it is possible to sequentially treat the treatment site without moving the applicator 216.

  Although the focus movement is electronically controlled here, it may be moved mechanically. When the focal point is mechanically moved, the piezo element is either a single spherical shell vibrator, a plurality of vibrators are driven simultaneously, or the phase control circuit group 118 is fixed. Just do it. Further, electronic control and mechanical control may be combined with focus movement. For example, electronic control may be performed in the depth direction, and the piezo element may be mechanically translated in the azimuth direction.

Next, a method for detecting motion between images using spatial frequency data in this reference example will be described.

  First, a case where an impulse response is used will be described. Assuming that the object moves between a plurality of images, the image after the movement is equivalent to the result of convolution integration of the impulse moved by the motion vector on the image before the movement. In FIG. 11, an image signal will be described with one line. If FIG. 11 (a) is the original image f (x) and FIG. 11 (c) is the image g (x) after the movement, FIG. 11 (c) shows the displacement of the motion vector from the center (0). This is equivalent to the convolution integral of the impulse h (x) shown in FIG. This relationship is expressed by the following equation.

g (x) = f (x) * h (x) (1)
h (x) = σ (x−a) * represents a convolution integral, and σ (x) represents a delta function.

  Therefore, when the impulse response between the two images in FIGS. 11A and 11C is calculated, FIG. 11B is obtained, and the deviation from the center of this peak becomes the motion vector. An MRI image is generally obtained by acquiring spatial frequency data, which is a magnetic resonance signal, and performing a Fourier transform on the MRI image. Therefore, after data collection, the quotient of the frequency data of the two images ( That is, if a transfer function is calculated and reconstructed, a motion vector can be detected.

When both sides of the equation (1) are Fourier transformed as g (x) → G (kx), h (x) → H (kx), f (x) → F (kx), respectively, G (kx) = F (kx)・ H (kx) (2)
∴ H (kx) = G (kx) / F (kx) (3)
Thus, an impulse response h (x) that is an inverse Fourier transform of the transfer function H (kx) can be easily calculated. A specific transfer function is calculated by using a Wiener filter, an adaptive filter, an optimum filter, etc. in addition to simple division for each frequency.

Next, the case where a cross correlation function is used will be described. When the cross-correlation function of the two images is calculated, the motion vector can be calculated from the peak at the position of the highest correlation between the two images. The cross-correlation function w (x) of the two images f (x) and g (x) is

It is. As is clear from this equation, a that maximizes W (x) is a motion vector. Also in this case, the cross-correlation function can be calculated by calculating the product of two image data in the frequency domain as shown in the following equation (5) and taking the inverse Fourier transform.

W (kx) = F (kx) · G (kx) (5)
In the case of such processing in the frequency domain, it is necessary to apply a window in order to reduce the influence of discontinuity at the edge of the image. Although the description has been given for one dimension here for simplicity, the motion vector can be calculated from the collected spatial frequency data similarly in two or three dimensions.

  When adapting to temperature distribution measurement, especially in the case of the phase mapping method of chemical shift temperature measurement, this is a method in which the temperature change is reflected in the phase information of the image, and the absolute value image shows the form. Using an absolute value image, a difference is calculated between phase images whose positions are corrected based on the absolute value image.

  FIG. 12 schematically shows a method of detecting a motion from data obtained by MRI, correcting the motion, and calculating a difference. (A) and (b) are the collected spatial frequency data. A transfer function (c) between them is calculated, and (a), (b), and (c) are reconstructed as (d), (e), and (f), respectively. Then, the difference is calculated by moving (d) and (e) by the motion vector obtained from (f). For example, when (a) is calculated before the ultrasonic irradiation, and (b) is calculated as an image obtained during the ultrasonic irradiation, the difference (h) due to the temperature change is drawn.

  Next, a treatment procedure using this motion detection function will be described with reference to the flowchart shown in FIG. First, the case where the phase mapping method of chemical shift temperature measurement is used will be described.

  First, before treatment, a three-dimensional high-definition image is taken by MRI (step S201), a treatment site is set on the image, and a treatment plan is formulated (step S202). Immediately before treatment, the patient is placed in the gantry (step S203), and a three-dimensional image for alignment is taken (step S204). Next, a positional shift between the three-dimensional image obtained in step S203 and the treatment plan image obtained in step S201 is detected (step S205), and whether or not the amount of the deviation is less than a threshold value. (Step S206), if it is equal to or greater than the threshold value, it is determined that the position is shifted, a motion vector is detected using the motion vector detection method, and the shift is corrected using this motion vector ( Step S207).

  If it is determined in step S206 that the position is not displaced, or if displacement correction is performed in step S207, an initial image of the temperature distribution (three-dimensional) is taken immediately thereafter, and then a continuous temperature distribution is obtained. Measurement (morphological images are also acquired simultaneously) is started (step S208), and these image data are stored in the memory (step S209). While obtaining this image, a motion vector for the initial image or the previous image is detected (step S210), and at the same time, the image is reconstructed (step S211). After the position of the subsequent image is moved so as to cancel the movement, the difference between the phase images is calculated (step S212), and a temperature distribution image is obtained.

  On the other hand, ultrasonic irradiation for treatment is performed independently of MRI imaging. That is, N focal positions are set in order (steps S214 to S216 → S220), and ultrasonic irradiation is performed (step S221). After all the set focal positions have been treated, MRI imaging is performed (step S217). When a sufficient therapeutic effect is confirmed at the site to be treated (step S218), the treatment is terminated (step S219). At this time, the coordinate reference is changed from time to time based on the motion vector information obtained in step 210 from the MRI side (step S221). Further, the heating position (hot spot) can be detected from the temperature distribution obtained during the ultrasonic irradiation. If the hot spot deviates from the site to be treated, the ultrasonic irradiation side is controlled to correct this.

  Even when a hot spot is observed by detecting an image change due to the temperature of a T1-weighted image (T1: longitudinal relaxation time), treatment can be performed in exactly the same flow, but the difference-taking image is an absolute value image. . In the case of a T1-weighted image, a position where the intensity of the image signal has changed from a predetermined threshold value may be detected as a hot spot without calculating the difference. In this case, the motion vector information is used only for correcting the ultrasonic irradiation position.

  FIG. 14 shows a schematic diagram of the temporal flow of motion correction based on the initial image reference and FIG. 15 shows the previous image reference. In FIGS. 14 and 15, irradiation is performed to such an extent that the tissue is not damaged first, and a time table for one irradiation when performing treatment irradiation after confirming that the hot spot is in the treatment planned site is shown. Show. In FIG. 14, the movement with respect to the reference image is always detected, and the temperature change from the reference image is measured for the temperature change. In FIG. 15, a motion with respect to the immediately preceding image is detected, and a change in the temperature with respect to the immediately preceding image is also measured. Therefore, the movement is performed on the immediately preceding image, and the accumulated temperature distribution is calculated for the temperature change. In such a case, in order to reduce the accumulated error, for example, once for every 10 imagings, the motion of the image relative to the initial image is detected and the coordinates are corrected.

As described above, according to the present reference example , in a treatment apparatus using an image diagnostic apparatus, a motion image is detected in real time by detecting a motion vector at a higher speed than in the past from spatial frequency data continuously obtained by MRI. The error of the movement is reduced, the shift of coordinates due to movement is reduced, and safe and accurate treatment becomes possible.

(Example )
Next, examples of the present invention will be described. The basic configuration of the apparatus of this embodiment is the same as that of the fourth reference example shown in FIG.

FIG. 16 shows a sequence for performing the point temperature in real time by chemical shift temperature measurement by local excitation according to the present embodiment . RF is a high frequency pulse, Gx, Gy, and Gz are gradient magnetic fields, and daq is a data collection period. Here, spin echo is applied, and a point (strictly, a cylinder) is locally excited by using one-shot local excitation on the xy plane and normal selective excitation in the z direction for local excitation. However, without performing such gradient magnetic field control, only one desired echo signal can be obtained by slicing in the x, y, and z directions as shown in FIG. In these cases, the data acquisition is completed in one sequence execution without using the read and encode gradient magnetic fields. As data, the signal intensity in the excited voxel is observed. Here, since the spectrum is observed when the one-dimensional Fourier transform is performed, the spectrum intensity of water can be observed more selectively. When the temperature measurement at this point is performed using the phase mapping method of chemical shift temperature measurement (Y. Ishihara et al .: Proc. 11th Ann. SMRM Meeting, 4803, 1992), the phase data and reference data of the obtained signal are used. What is necessary is just to calculate the difference of phase data.

  Hereinafter, a case will be described in which one of the treatment points set at the time of treatment planning is treated as a treatment procedure using this temperature measurement. A schematic diagram of this temporal flow is shown in FIG.

  First, for example, a three-dimensional image of the temperature distribution when heating is performed to such an extent that the tissue is not affected (C1), the heating site (hot spot) is confirmed in advance, and the deviation from the set position is detected. Then, the point of local excitation is set to the maximum heating point or a part exceeding a preset temperature threshold (C2). This threshold is determined from the temperature at which the tissue is affected during the irradiation of high-power therapeutic ultrasonic waves. The process at this time is shown in FIG. When the temperature distribution as shown in FIG. 22 (a) is obtained, only the portion above the threshold is extracted as shown in (b), and a representative point (for example, the maximum heat generation point therein) is extracted from the extracted portion. Extract as shown in (c). Here, the temperature measurement site is determined from the temperature distribution image. However, the operator may designate a site to be temperature monitored, such as a treatment site or a site that should not be heated, from a separately obtained morphological image.

  Next, high power irradiation for treatment is performed, and at this time, chemical shift temperature measurement is performed at the temperature measurement point set in C2 (C3). If the expected temperature rise is obtained at the desired site, the irradiation is continued (C4 → C5). If the temperature rise is not sufficient, the focus is shifted and the irradiation is stopped (C4 → C6). Generate an alarm. For a site that is not intended to be heated, a threshold value is given to the upper limit of the temperature at which the temperature does not damage the tissue. If this threshold is exceeded, the treatment is stopped and an alarm is generated. Then, the same treatment is performed for the next focus.

  The measured temperature is displayed as a change in temperature with respect to time on the sub-windows 221 and 222 on the display (for example, the image display in FIG. 10) as shown in FIG. 18, and the measurement position is displayed on the morphological image shown on the main window. Indicated by arrows. If the temperature graph exceeds the dangerous temperature, or if the temperature rise is abnormal, the temperature is displayed in a different color to notify the operator of the abnormality. Further, the position shape 223 of the ultrasonic transducer, the geometric focal point 224, and the like may be superimposed and displayed in the morphological image. Furthermore, the temperature distribution obtained at the time of weak ultrasonic irradiation may be displayed in an overlapping manner or may be switched.

  Next, a case where treatment is performed while measuring a one-dimensional temperature distribution on the ultrasonic irradiation axis at a high speed will be described. The sequence at this time is shown in FIG. Here, a case where a total of two local excitations in the x and y directions is performed and only one z-axis excitation is performed is shown. A field echo sequence is used as the sequence, and a one-dimensional temperature distribution in the z-axis direction is obtained by reading in the z-axis direction. In actual use, the excitation direction is set using the oblique imaging method so as to match the irradiation direction (on the irradiation axis). At this time, the vector directions of the gradients of the first excitation, the second excitation, and the lead are all set to be orthogonal to each other.

  In addition, a case will be described in which a treatment procedure using this temperature measurement is treated for one of a plurality of treatment points set during treatment planning. Moreover, the schematic diagram of this time flow is shown in FIG.

  First, the temperature distribution when heating is performed to such an extent that the tissue is not affected is three-dimensionally imaged (C1), the heating site (hot spot) is confirmed in advance, and the deviation from the set position is detected. Further, the local excitation line is set so as to include the maximum heating point or a portion (plurality) exceeding a preset temperature threshold (C2). The setting procedure at this time is the same as in FIG. Similar to the point temperature measurement, the operator may specify a line to be monitored.

  Next, high power irradiation for treatment is performed, and at this time, chemical shift temperature measurement is performed on the temperature measurement line set in C2. Here, the spatial frequency data obtained after one excitation is subjected to a one-dimensional Fourier transform (C3), and a one-dimensional temperature distribution is calculated (C4). If the expected temperature rise is obtained at the desired site, the irradiation is continued (C5 → C6). If the temperature rise is not sufficient, the focus is shifted and the irradiation is stopped (C5 → C7). Generate an alarm. For a site that is not intended to be heated, a threshold value is given to the upper limit of the temperature at which the temperature does not damage the tissue. If this threshold is exceeded, the treatment is stopped and an alarm is generated. Thereafter, treatment is similarly performed for the next focus.

  Then, representative points of the temperature distribution measured at C4 are displayed as shown in FIG. Alternatively, as shown in FIG. 21, the temperature distribution may be displayed again on the morphological image on the main window every time the temperature is measured by changing the color and superimposing. In this case, the scheduled heating profile is displayed in a different color or dotted line, and an alarm is generated when there is a deviation from that. This temperature distribution may be displayed in the main window with the measurement line displayed in a sub-window indicated by an arrow.

  The morphological image shown so far may be an image obtained before treatment or an image obtained after the heating of one heating point is completed.

  Moreover, you may use the temperature obtained during treatment irradiation by the same treatment sequence for control for ultrasonic irradiation. For example, as shown in FIG. 26, the temperature change expected from the irradiation condition is compared with the actually measured temperature by determining the difference between the two (C1), and the ultrasonic irradiation power is set so as to eliminate this difference. Control (C2). For example, if the measured temperature is lower than the set temperature, it may be controlled to increase the irradiation power.

  Next, a method for simultaneously checking the temperature monitor and the therapeutic effect will be described.

  Here, temperature measurement is performed at points or lines, and relaxation time emphasis data is acquired almost simultaneously. Regarding T2 (lateral relaxation time) enhancement, temperature measurement is continuously performed at points or lines during ultrasonic irradiation, and after the irradiation returns to normal temperature, a T2-weighted image is acquired, and then the next irradiation starts immediately. . At this time, even when the T2 weighted signal is acquired, the treatment time can be shortened by measuring the T2 weighted signal at the planned treatment point using local excitation instead of an image in the procedure as shown in FIG. it can. At this time, since the relaxation time also changes when the temperature rises, this may be corrected by the temperature obtained by the chemical shift temperature measurement. By doing so, temperature monitoring and treatment effect confirmation can be performed simultaneously.

  As shown in FIG. 23, after irradiating a weak ultrasonic wave, after measuring the image or temperature and confirming the position and temperature, if there is no abnormality, immediately irradiate the strong ultrasonic wave to check and for the actual treatment The time lag at the time of irradiation can be reduced, and the positional deviation between them can be reduced.

  As for the longitudinal relaxation time T1, if a field echo is used during temperature measurement, a T1-weighted image can be obtained simultaneously as an absolute value image. Since it is known that the relaxation time T1 also changes due to denaturation, the temperature of the point or line is measured during therapeutic ultrasonic irradiation, and the absolute value of the temperature distribution measured at the time of weak ultrasonic irradiation before irradiation of the next focal point The therapeutic effect is also determined from the image.

  FIG. 24 shows a sequence in which temperature measurement and T1, T2 weighted images are acquired in the same sequence. This is an application of the CPMG (Carr-Purcell-Meiboom-Gill) sequence. By using a 180 ° pulse multiple times after one point of local excitation, multiple echo time signals can be obtained. The T1 weighted signal is obtained from the temperature and the absolute value from the phase of the signal obtained at TE1, and the T2 weighted signal is obtained from the absolute value at the long echo time TE2.

  In this case, the T1 and T2 emphasis signals may be corrected from the temperature. Thereby, a temperature monitor and a therapeutic effect confirmation can be performed by one excitation. At this time, the repetition time TR may be shortened, the 90 ° pulse may be an Ernst angle pulse, the temperature may be measured by field echo, and then the 180 ° pulse may be added to obtain a T2W signal.

In this embodiment, the pin echo sequence and the field echo sequence are used as the MRI pulse sequence. However, other sequences can be used in the same manner as long as local excitation is included. Further, in this embodiment, ultrasonic waves are used as treatment energy in order to treat an affected area particularly in the deep region. However, a laser is used when large energy is input at once, and a microwave is applied when energy is applied to a wide area. It is possible to carry out heat treatment even if it is used appropriately, and this embodiment can be applied to all temperature monitors at this time.

  As described above, according to the present embodiment, in the treatment apparatus using the magnetic resonance diagnostic apparatus, it is possible to perform the temperature measurement on the necessary points of the temperature monitor obtained in advance using the local excitation method in real time. Thus, it is possible to provide a safe treatment apparatus that can detect abnormalities during irradiation.

( 5th reference example )
Next, a fifth reference example will be described. The basic configuration of the apparatus of this reference example is the same as that of Reference example 4 shown in FIG.

In this reference example , a procedure for performing treatment while measuring the one-dimensional temperature distribution on the ultrasonic irradiation axis at high speed will be described. Here, the irradiation axis is an axis connecting the center of the spherical surface of the spherical shell ultrasonic transducer and the center of the transducer. FIG. 27 shows a pulse sequence at this time. Here, a case where a total of two local excitations in the x and y directions is performed and only one z-axis excitation is performed is shown. A field echo sequence is used as the pulse sequence, and a one-dimensional temperature distribution in the z-axis direction is obtained by reading in the z-axis direction. In actual use, the excitation direction is set using the oblique imaging method so as to match the irradiation direction (on the irradiation axis). At this time, the vector directions of the gradients of the first excitation, the second excitation, and the lead are all set to be orthogonal to each other.

  Regarding the detection and control of the position and irradiation axis direction of the ultrasonic applicator 216, the case where the position and irradiation axis direction are controlled by the electronic computer 213, the case where the operator controls via the electronic computer 213, and the direct applicator. Are divided into cases where the operator moves.

  First, the flow of control in the former case is shown in FIG. The electronic computer 213 sets the position and angle of the applicator 216 as determined in advance during the treatment plan, and transmits them to the sequence controller 205 and the applicator drive system 231. Accordingly, the ultrasonic irradiation axis is also calculated. Imaging conditions are determined so as to include the axis, and temperature measurement is performed during heating.

Moreover, the case where the treatment procedure at this time treats one of the treatment points set at the time of treatment planning will be described as an example. Further, this temporal flow is the same as that of FIG. 20 used in Reference Example 5 above.

  Referring to FIG. 20, first, a temperature distribution when heating is performed to such an extent that does not affect the tissue is three-dimensionally imaged (C1), and the heating site (hot spot) is confirmed in advance. The deviation from the set position is confirmed, and the local excitation line is set so as to include a maximum heating point or a part (plurality) exceeding a preset temperature threshold (C2). The setting procedure at this time is the same as in FIG. At this time, imaging may be performed on the surface including the axis already in accordance with the irradiation axis or on a multi-slice thereof.

  Next, high power irradiation for treatment is performed, and at this time, chemical shift temperature measurement is performed on the temperature measurement line set in C2. Here, the spatial frequency data obtained after one excitation is subjected to a one-dimensional Fourier transform (C3), and a one-dimensional temperature distribution is calculated (C4). If the expected temperature rise is obtained at the desired site, the irradiation is continued (C5 → C6), and if the temperature rise is not sufficient, the focus may be shifted and the irradiation is stopped (C5 → C7). Generate an alarm. For a site that is not intended to be heated, a threshold value is given to the upper limit of the temperature at which the temperature does not damage the tissue. If this threshold is exceeded, the treatment is stopped and an alarm is generated. Thereafter, treatment is similarly performed for the next focus.

  Then, representative points of the temperature distribution measured at C4 are displayed as shown in FIG. Alternatively, as shown in FIG. 21, the temperature distribution may be displayed again on the morphological image on the main window every time the temperature is measured by changing the color and superimposing. In this case, the scheduled heating profile is displayed in a different color or dotted line, and an alarm is generated when there is a deviation from that. This temperature distribution may be displayed in the main window with the measurement line displayed in a sub-window indicated by an arrow.

  Next, a case where the operator controls the applicator 216 via the electronic computer 213 will be described. As shown in FIG. 29, first, the operator inputs position and angle data to the potential calculator 213 from the keyboard 231 or the morphological image displayed on the display by the electronic calculator 213 and the computer graphics of the ultrasonic applicator 216 (both When the applicator in the image is moved using the mouse 232, 3D pointer 233, and keyboard 231 based on the (pseudo three-dimensional image), the position and angle data at that time are fed back to the MRI imaging conditions and include the irradiation axis. Line and surface temperature distributions are collected. In addition, you may actually display three-dimensionally using a three-dimensional display.

Next, a case where the operator moves the applicator 216 directly will be described.
FIG. 30 shows a configuration diagram of a hand probe type ultrasonic therapy applicator using an MRI monitor. Here, an open type MRI magnet 300 is used. The encoders 301, 302, and 303 are rotation detection type encoders, and the encoders 304, 305, and 306 are translation detection type encoders, which enable rotation and movement with six degrees of freedom of the translation meter. When the operator grasps the grasping unit 307 and aligns the affected part with the affected part, signals from the respective encoders 301 to 306 can be sent to the computer, and the position and angle of the applicator 216 can be constantly calculated and grasped. These position and angle data are fed back to the MRI imaging conditions, and line or plane data including the irradiation axis is collected. In the case of line data collection, a pulse sequence as shown in FIG. 27 is used, and in the case of a plane, a normal MRI two-dimensional imaging pulse sequence is used.

  Here, an encoder is used to detect the position and angle of the applicator 216, but detection may be performed using an optical gyro instead. A schematic diagram in this case is shown in FIG. The positions of two points of the applicator 216 are measured by the optical gyros 311 and 312. The position information is sent to the electronic computer 213, and MRI imaging suitable for the position is performed.

  In addition, the position and angle can be detected using a television camera. A schematic diagram of the detection method at this time is shown in FIG. Here, the cameras 323 and 324 are installed in two directions, and the applicator is provided with self-lighting pointers 321 and 322 such as LEDs, and light from these pointers 321 and 322 is transmitted from the two directions. The position and angle of the applicator 216 can be calculated by measuring and calculating the three-dimensional pointer position from the positions of the cameras 323 and 324.

  At this time, a display that is not easily affected by a magnetic field such as a liquid crystal display is placed in a shield room at a position where an operator can see it, and a morphological image of the surface including the irradiation axis and a temperature distribution image are displayed here. . The morphological image at this time may be constructed from three-dimensional image data obtained in advance, or images of the same surface may be collected alternately or simultaneously with the temperature distribution. Alternatively, the morphological image may display three-dimensional data as a pseudo three-dimensional image, and display a two-dimensional or one-dimensional temperature distribution image in an overlapping manner.

  When an operator performs an interactive treatment by controlling an input device such as a mouse 232 or 3D pointer 233 or an applicator 216 as shown in FIG. 29, a switch is installed on the input device or applicator 216. deep. First, morphological images are continuously acquired in real time for the surface including the irradiation axis, and the morphological image and the planned heating portion are displayed in an overlapping manner. The applicator 216 or the input device is moved so that the treatment planned site (affected part) and the heating planned site are aligned. When the coincidence is confirmed, the switch is operated, and ultrasonic heating is performed with a very weak intensity that does not damage the tissue. The temperature distribution is measured simultaneously under the control of the electric potential calculator 213, and it is determined whether or not the heating part in the measured temperature distribution matches the scheduled part using the electronic computer 213, and automatically powerful by the control of the electronic computer 213. Irradiate with ultrasound immediately.

  However, since the positional deviation occurs three-dimensionally, when two-dimensional or one-dimensional imaging is performed, the positional deviation may occur in the slice direction. At this time, know the temperature rise with respect to the irradiation power in advance, if it does not reach this, it is determined that a positional deviation has occurred, and the temperature is measured in the same way in another slice, and compared with this, the slice direction Know the maximum heating position. Alternatively, multi-slice imaging may be performed to detect a three-dimensional positional deviation. Further, although it may be orthogonal or simply crossed, the temperature distribution of a plurality of screens may be imaged, and the slice including the maximum temperature rise point in each plane may be imaged again.

  The operator confirms the match between the heated area and the planned treatment area, and manual irradiation of intense ultrasonic waves with another switch may be performed, or the heated area and the heated area during weak heating coincide. It is also possible to automatically irradiate with powerful ultrasonic waves after confirming with a computer. Alternatively, a phased array may be used for the piezo element, and the deviation at this time may be corrected electronically by phase control.

In addition, in this reference example , ultrasonic waves were used as the treatment energy to treat the affected part in the deep local area. However, a laser is used to apply large energy at once, and a microwave is used to input energy to a wide area. It is possible to perform heat treatment even using the above, and the method of this reference example can be applied to all temperature monitors at this time. In this case, for example, even with a laser, the temperature of the surface including the irradiation axis may be measured.

As described above, according to the present reference example , in a treatment apparatus using a magnetic resonance diagnostic apparatus, temperature information of a part corresponding to a treatment position can be constantly obtained at high speed, and treatment with high treatment efficiency and safety can be achieved. It becomes possible.

( Sixth reference example )
FIG. 33 is a diagram showing the configuration of the sixth reference example . In the figure, an ultrasonic applicator 401 includes a piezo element 402, an ultrasonic probe 40 for imaging and a flexible water bag 404 that are inserted and arranged at the center thereof. The applicator 401 uses an acoustic energy propagation medium 407 (for example, water) made of a substance having an acoustic impedance close to that of a living body to treat a treatment target 406 in the body of the patient 405 as shown in the figure. 405 is contacted.

  The piezo element 402 is driven by a drive circuit 408. The drive circuit 408 is connected to the control circuit 409 and adjusts the drive voltage of the piezo element 402 by a control signal from the control circuit 409. The drive circuit 408 has two output terminals, which are independent of each other, but output the same signal. One output terminal of the drive circuit 408 is connected to one input of the piezo element 402 and the reception wave detection circuit 410, and the other output terminal is connected to the other input of the reception wave detection circuit 410.

  The reception wave detection circuit 410 detects a reflected ultrasonic signal from the treatment object 406 superimposed on the drive voltage. The level detection circuit 411 and the phase shift detection circuit 412 detect the level and phase of the reflected wave signal from the reception wave detection circuit 410, respectively, and output the information to the control circuit 409.

In this reference example , an in-vivo image acquired by the diagnostic ultrasound probe 403 and the ultrasound diagnostic apparatus 413 and information on a change in the treatment area from the control circuit 409 are converted into a CRT via a digital scan converter (DSC) 414. It is displayed on the display 415.

Next, the operation of this reference example will be described by taking an example of cauterization treatment using high-intensity ultrasound.

This reference example is characterized in that a change in the treatment area is detected in real time by a high-power ultrasonic wave for treatment emitted from the piezo element 402 toward the treatment object 406. The therapeutic ultrasound emitted from the piezo element 402 toward the focal point raises the temperature of the focal region to 60-80 degrees Celsius in a few seconds. As a result, the living tissue in the focal region undergoes thermal denaturation and dies. Thereafter, when irradiation with ultrasonic energy is further continued, the heat-denatured region expands. Since the acoustic characteristics of this heat-denatured necrotic living tissue are different from those of normal cells, ultrasonic waves are reflected at the interface between the heat-denatured part and the normal tissue. Also, the absorption coefficient of ultrasonic energy in the heat-denatured region is different from that of normal cells.

  Therefore, if a reflected wave from the vicinity of the heat-denatured region is detected and its amplitude is measured as described below, it is possible to know whether or not there is a change in the treatment region (heat-denatured state). Further, the situation in which the heat denaturation region expands can be monitored by detecting the phase shift due to the time of the reflected wave.

  The ultrasonic waves reflected in the vicinity of the heat-denatured region propagate to the applicator 410 side and reach the piezo element 402. Thereafter, the piezo element 402 is vibrated, and ultrasonic energy is converted into electric energy by the piezo element 402. In general, compared with the driving electric energy of the piezo element 402, the electric energy generated by the reflected ultrasonic waves is small, so that it is difficult to detect the reflected ultrasonic component.

Therefore, in this reference example , only a reflected wave signal component is detected by applying a signal that cancels the drive signal, which is an electrical signal, to the input side of the received wave detection circuit 410. The principle will be described with reference to FIG. FIG. 34 is a diagram schematically showing the piezo element 2, the drive circuit 408, and the received wave detection circuit 410. There are two output stages of the drive circuit 408, and different elements, in this example, transistors 431 and 432 are used. Of course, the output element may be an IC such as an operational amplifier, or another semiconductor element such as a thyristor. In short, it may be configured so that the output does not affect the input stage.

  A piezo element 402 as a load is connected to the collector side of the transistor 431. The same signal is input to the transistors 431 and 432, and the same signal as the drive signal applied to the piezo element 402 can be extracted from the collector of the transistor 432. At the collector of the transistor 431, a signal in which a reflected wave signal component from the vicinity of the heat denaturation region is superimposed on the drive signal appears.

  Signals from the collectors of the transistors 431 and 432 are input to the reception wave detection circuit 410, and the differential signal is detected by the differential amplifier 433. The differential amplifier 433 detects the difference signal and simultaneously amplifies it to output a signal component in which the drive signal component is canceled, that is, a reflected wave signal component.

  The magnitude of the reflected wave signal component detected by the reception wave detection circuit 410 is compared with a threshold value set in advance by the level detection circuit 411 in FIG. 33, and if it is equal to or greater than the threshold value, the control circuit 407 causes the drive circuit 408 to The drive signal to be supplied is turned off, and irradiation of therapeutic ultrasonic waves from the piezo element 402 is stopped immediately or after a certain time. The time width can be set by using the input unit 416 from the time when the level detection circuit 411 determines that the magnitude of the reflected wave signal component is equal to or greater than the threshold value until the irradiation of therapeutic ultrasonic waves is stopped. For example, when it is desired to enlarge the heat denaturation region to some extent, this time width may be increased. Note that the threshold given to the level detection circuit 411 can be arbitrarily set by the operator using the input unit 416. It is also possible to set a treatment procedure such as stopping the irradiation of therapeutic ultrasonic waves after a reflected wave of a threshold value or more continues for a certain time, so that the therapeutic effect required by the operator can be obtained. .

  Now, as the treatment area expands, the boundary surface where a part of the treatment ultrasonic wave is reflected also shifts to the applicator 401 side, so the time until the reflected wave is obtained after irradiation is gradually increased. This shortens the phase of the reflected wave signal. By detecting this phase shift by the phase shift detection circuit 412, it is possible to know the expansion of the heat denaturation region. Further, by integrating the amount of phase shift, a measure of the amount of expansion of the heat-denatured region from the focal position can be obtained. Thus, it is possible to control such as stopping the irradiation when the expansion of the heat denaturation region exceeds a set value. Here, the phase shift detection circuit 412 is configured to output, for example, a phase shift converted into a voltage, and can be configured by a well-known PLL circuit or phase comparator.

In addition, if this reference example is used, not only the heat-denatured state of the focal region but also the cavitation generation status, temperature rise, and body surface change can be measured. These are realized by comparing the amplitude change and phase shift of the reflected wave signal with those characteristic of them.

  The change of the treatment target obtained as described above is superimposed on the in-vivo ultrasonic image acquired by the ultrasonic diagnostic apparatus and displayed on the CRT display 415 to notify the operator. As this display method, for example, a mark indicating a heat-denatured region is superimposed on the focal point, and the size of the mark is changed according to the amount of movement of the denatured region toward the applicator 401 side, or the body surface of the patient 405 is displayed. It is also conceivable to use such as generating a warning by detecting temperature rise or denaturation.

( Seventh reference example )
FIG. 35 is a diagram showing the configuration of the seventh reference example . In FIG. 35, the imaging ultrasonic probe 403, the ultrasonic diagnostic apparatus 413, the digital scan converter 411, and the CRT display 415 shown in FIG. 33 are omitted.

In this reference example , two inputs of the reception wave detection circuit 410 are connected to the piezo element 402 and the drive circuit 408 and a newly provided memory 419. In FIG. 35, a reflected wave signal for one wavelength or several wavelengths immediately after irradiation of therapeutic ultrasonic waves is converted into a digital signal by the A / D converter 418 and then stored in the memory 419.

  Since there is no heat-denatured region immediately after irradiation of therapeutic ultrasonic waves, the signal at the electric signal input end of the piezo element 402 is a composite signal of the drive signal and a minute reflected wave signal from the living tissue. When the treatment progresses and the heat denaturation region becomes apparent, a change occurs in the reflected wave signal, and this is detected to obtain heat denaturation information. As this procedure, the reception wave detection circuit 410 having the configuration shown in FIG. 36 is used.

That is, as shown in FIG. 36, the drive signal (received signal) on which the reflected wave signal component received by the piezo element 402 is superimposed is first converted into a digital signal by the A / D converter 441. The signal stored in the memory 419 is adjusted according to the output and phase of the drive circuit 408 by the phase and level adjustment circuit 442 according to the control signal from the control circuit 409. Then, the subtractor 443 digitally subtracts the output signal of the phase and level adjustment circuit 442 from the output signal of the A / D converter 441. As a result, only the reflected wave signal component is extracted. Note that the output signal of the memory 419 may be converted into an analog signal by the D / A converter 444, and then the difference from the analog signal from the piezo element 402 may be taken. The subsequent operation is the same as that in FIG. 33. The amplitude change and the phase shift of the reflected wave signal are detected, and the control ultrasonic wave is controlled by the control circuit 8 based on the information. Note that the output stage D / A converter 444 in FIG. 36 may be removed, and the level detection circuit 411, the phase shift detection circuit 412 and the control circuit 408 in FIG. 35 may be digitized. In this reference example , a signal of one wave or several waves immediately after irradiation of therapeutic ultrasonic waves is acquired and stored in the memory 419. However, a drive signal waveform may be stored in the 419 in advance at the time of manufacture.

( Eighth reference example )
FIG. 37 is a diagram showing the configuration of the eighth reference example , and is an example in which a drive signal used for detecting a reflected wave signal is created by another oscillator. In this reference example , the output and phase of the oscillator 420 are controlled by the control circuit 409 so as to correspond to the magnitude and phase of the output of the drive circuit 408. This is the same as Reference Example 7 except that the difference between the output of the oscillator 420 and the received signal is taken.

( Ninth Reference Example )
FIG. 38 is a diagram illustrating the configuration of the ninth reference example . In this reference example , annular array type ultrasonic wave generation sources 402 a to 402 f are used for the applicator 401. The annular array type ultrasonic wave generation sources 402a to 402f are constituted by a plurality of piezo element groups, and are divided into a plurality of concentric rings. Each ring can be driven independently, and the drive timing can also be controlled independently.

In this reference example , the reflected wave signal detection method described in Reference Example 6 is performed for each ring of the annular array type ultrasonic wave generation sources 402a to 402f. Here, when the heat denaturation region changes to the front, the position on the axis of the applicator 401 can be quantitatively detected by calculating the phase shift for each ring. By performing irradiation control based on this data, safer and more reliable treatment is possible.

Furthermore, if a therapeutic ultrasonic wave generation source is configured by arranging piezo elements in a two-dimensional array, it is possible to realize a focus shift type treatment apparatus using this reference example .

As described above, according to the present reference example , it is possible to perform real-time monitoring of the treatment region by the ultrasonic treatment system by detecting and analyzing the reflected wave of the treatment ultrasonic wave from the treatment region. Furthermore, safe and reliable treatment can be realized by controlling the therapeutic ultrasound based on the obtained treatment area information.

( 10th reference example )
FIG. 39 is a diagram illustrating a configuration of an applicator according to a tenth reference example . As the support body 501 for insertion into the body cavity, a flexible cylinder having a certain degree of strength is used. For this reason, it is possible for the operator to freely adjust the inclination of the tip with the hand of the applicator.

  The transducers 502 a and 502 b that emit therapeutic ultrasonic waves are each formed in a semicircular shape having a concave shape and a different size, and the transducer 502 b is relative to the transducer 502 a around the rotation axis 503. It is being fixed to the support body 501 so that it can rotate. Since the transducers 502a and 502b are semicircular, the relative rotation changes the overlapping area of the transducer 502b with respect to the transducer 502a as viewed in the ultrasonic wave transmission direction.

  A lead for supplying a drive signal to the vibrators 502 a and 502 b is not shown, but is coupled to a drive circuit body (not shown) through the inside of the support 501. In addition, a flexible membrane 504 is attached to the support 501 in a watertight manner so as to cover the whole of the vibrators 502a and 502b, and deaerated water passes through an opening 505 of a tube (not shown) passing through the support 501. The size of the outer shape of the applicator can be adjusted by supplying and draining a liquid for ultrasonic coupling. Further, the body surface and the vibrator surface can be cooled by circulating the coupling liquid.

  FIG. 40 shows an AA ′ cross section of the applicator of FIG. As shown in the figure, the transducers 502a and 502b have concave curvature radii different from each other, but the transducer 502b having the smaller curvature radius is arranged inward by the difference in curvature radius from the transducer 502a having the larger curvature. As a result, the same geometrical focal point 506 is provided. In addition, a rotation mechanism 507 for rotating the vibrator 502b around the rotation shaft 503 is attached inside the support body 501, and the operator uses, for example, a wire provided at the hand of the support body 501. The rotation mechanism 507 can be operated by an operation mechanism (not shown). This structure is a technique known to those skilled in the art.

  The applicator is inserted from the esophagus into the body cavity of the patient, for example, the stomach, with the transducer 502a overlaid on the transducer 502b as shown in FIGS. In this state, since the vibrator 502a overlaps the vibrator 502b, the maximum diameter of the applicator is reduced, so that the vibrator 502a can be easily inserted into the body cavity. Once the distal end of the applicator reaches the stomach, the operator operates the rotation mechanism 507 by the operation mechanism to rotate the vibrator 502b by approximately 180 °, thereby moving the vibrator 502b with respect to the vibrator 502a. The state shown in FIG. 41 and FIG. In this state, the aperture diameter when viewed as a whole of the transducers 502a and 502b is maximized, and the ultrasonic energy can be sharply focused to a deep site. At this time, the flexible membrane 504 does not interfere with the rotating vibrator 502b, and increases the amount of coupling fluid in the interior in order to achieve sufficient contact with the patient.

  Here, the radii of curvature of the transducers 502a and 502b, that is, the distances R1 and R2 from the geometric focal point 506 to the transducers 502a and 502b are different, but this distance difference ΔR = R1−R2 is the wavelength of the therapeutic ultrasound. The relationship is an integer multiple. As an example, when 4 MHz is used as the ultrasonic frequency, the thickness of the transducers 502a and 502b is about 0.5 mm when ordinary PZT is used. Although not shown, a space of 1 mm or more is required as the distance difference ΔR between the transducers 502a and 502b for backing to hold the transducers 502a and 502b and for routing the electric wires. If the sound velocity of the coupling liquid is 1500 m / sec, the wavelength in the coupling liquid is 0.375 mm. Therefore, ΔR is an integral multiple of the wavelength, and is set to 1.875 mm, for example, for five wavelengths. It is. Therefore, even if the transducers 502a and 502b are simply electrically connected in parallel and connected to the same drive circuit, the ultrasonic waves radiated from the transducers 502a and 502b have the same phase at the geometrical focal point 506 and are used for focus formation. There is no big problem.

  However, strictly speaking, since the transducers 502a and 502b have different distances from the geometric focal point 506, the ultrasonic intensity per unit solid angle when the transducers 502a and 502b are viewed from the geometric focal point 506 is slightly unbalanced. (The vibrator 502b is larger than that of the vibrator 502a). In order to prevent this, for example, a method of dividing the drive voltage applied to each transducer 502a, 502b with an appropriate division ratio so that the ultrasonic intensity per unit solid angle becomes equal on the drive circuit side, etc. Take it.

As described above, according to the reference example , when inserting into a body cavity, the insertion is facilitated with the maximum diameter of the applicator being reduced, and focusing at a geometrical focus is performed by increasing the opening of the entire vibrator during treatment after insertion. This makes it possible to generate a powerful ultrasonic wave only in a limited area and perform an efficient treatment.

( 11th reference example )
FIG. 43 is a configuration diagram of an ultrasonic therapy apparatus according to the eleventh reference example , and particularly shows a configuration of an applicator and an apparatus main body suitable for use with a laparoscope.

In FIG. 43, the support body 511 is a hard cylinder, and an angle mechanism 512 that can change the angle with the hand of the applicator is formed at the tip. Similar to Reference Example 11, two sets of vibrators 513a and 513b are provided. In this reference example , these vibrators 513a and 513b are flat plates and the surface is divided into a plurality of (N) elements. A two-dimensional array structure is formed.

  The vibrators 513a and 513b are slidable in the horizontal direction. When the vibrators 513a and 513b are inserted, the vibrators 513a and 513b are completely overlapped with each other. Each array element of these vibrators 513a and 513b is coupled to an independent drive circuit group 514, and each drive timing is determined by a trigger signal transmitted from the delay circuit group 516 in accordance with a signal from the control circuit 515. As a result, a position-variable focal point 517 is formed. At this time, the condition of the treatment target in the vicinity of the focal point 517 is controlled by using the image ultrasonic transducer 518 and the ultrasonic diagnostic apparatus 519 which are configured in the support body 511 in the vicinity of the treatment vibrators 513a and 513b. A tomographic image is formed on the CRT display 520 via the circuit 515. Here, the control circuit 515 obtains the position of the focal point 517 by calculation and displays it on the image of the CRT display 520 in an overlapping manner. During the treatment, the water control circuit 521 fills the flexible film 504 at the tip of the applicator with the opening 505 to fill the coupling liquid in response to an instruction from the control circuit 515, and heating of the vibrators 513a and 513b itself is expected. If so, circulate and cool.

  FIG. 44 shows an example of the slide-type moving mechanism described above. Two vibrators 532 a and 533 b are attached to the tip of the support 531. The vibrators 532a and 563b are linear arrays in the longitudinal direction of the support body 521, and have a concave shape in the width direction. The moving element 532 a is fixed to the support 531, and the vibrator 532 b is fixed to a support column 533 that can slide in a groove 534 formed obliquely on the support 531. The column 533 slides along the groove 534 to convert the longitudinal movement of the support 531 into the sliding movement of the vibrator 532b.

  Thus, after the vibrator 532b is slid, the vibrators 532a and 532b have the positional relationship shown in FIG. 45 and have a common concave geometric focus 535. A focal point can be formed in the longitudinal direction of the vibrators 532a and 532b by the electron focusing action of the linear array. 44 and 45, the flexible film for coupling is omitted.

As described above, according to the present reference example , a therapeutic ultrasonic transducer having a large opening can be inserted even into a body cavity where the insertion portion is very narrow. It is possible to perform an effective treatment by irradiating with a powerful ultrasonic wave focused on.

( 12th reference example )
FIG. 46 is a configuration diagram of the twelfth reference example . First, the configuration of the applicator 601 in FIG. 46 will be described with reference to FIG. As shown in FIG. 47, the applicator 601 includes an ultrasonic transducer 602 that irradiates a therapeutic high-power ultrasonic wave, a coupling liquid 604 that guides the strong ultrasonic wave to a patient 603, and a water bag that seals the coupling liquid 604. 605 and a housing 633 for housing them.

  The housing 625 is provided with three or more reference points 608A, 608B, and 608C for use in focus positioning (here, three points will be described). The reference points 608A, 608B, and 608C are made of a material that can be clearly depicted on an MRI image and can be easily distinguished from a biological material, and the material is preferably a non-magnetic material. Specifically, oils injected into the holes of the housing material, rubbers, or resins attached may be used.

  As shown in FIG. 48, the ultrasonic transducer 602 has a shape obtained by dividing a circular flat plate piezoelectric element in the radial direction and the circumferential direction. When treating, the applicator 601 is placed on the body surface, and the water bag 605 is brought into contact with the skin of the patient 603 via an ultrasonic jelly or the like (not shown). Then, after the focal point 607 coincides with the tumor 606, the ultrasonic transducer 602 is driven by the drive circuit group 611 to irradiate with strong ultrasonic waves, and the treatment site coincident with the focal point 607 is maintained at a high temperature for treatment.

In this reference example , a phased array was used as a powerful ultrasonic wave generation source. Therefore, by controlling the drive timing of the drive circuit group 611 by the phase control circuit group 610, the focus position, the sound field, and the heating / heating region can be operated without moving the applicator 601 and the ultrasonic transducer 602. Can do. The drive circuit group 611 is divided into the number of channels of the divided ultrasonic transducers 602, and is driven by an independent timing signal given a delay by the phase control circuit group 610 based on a signal from the heat treatment apparatus control circuit 609. Is done. Thereby, the focal point 607 of the ultrasonic wave can be set at an arbitrary place three-dimensionally. The operation of moving the focal position by this delay time control is described in detail, for example, in USP-4,526,168.

Next, the positioning and MRI image imaging unit in this reference example will be described.

  First, the patient 603 is set on the treatment table 620, and with the applicator 601 attached, the table moving device 613 controlled by the MRI control circuit 614 uses the RF coil 619, the static magnetic field coil 617, and the gradient magnetic field coil. The coil 618 is fed into a gantry (not shown) for MRI imaging.

  The MRI control circuit 614 starts up the gradient magnetic field power source 616 and the transmission / reception circuit 615 by a predetermined sequence (for example, T2-weighted imaging method: T2 lateral relaxation time) instructed from the console 621, and the reference points 608A, 608B, 608C of the applicator 601. Is stored in a memory (not shown). This three-dimensional information can be displayed on the CRT display 612 by the MRI control circuit 614. However, as described in JP-A-5-300910, for example, an arbitrary one such as a pseudo three-dimensional display using a wire frame can be used. Can also be displayed.

  Next, the tumor 606 and the focal point 607 are aligned. Here, on the CRT display 612, as shown in FIG. 49, an MRI two-dimensional image inside the patient including the reference point 608A is displayed. The operator inputs the position of the reference point 608A on the MRI coordinate 626 to the heating device control circuit 609. Alternatively, the MRI control circuit 614 may recognize the reference point 608A of the applicator 601 and send the coordinate information to the heating treatment apparatus control circuit 609. The same operation is performed on the remaining reference points 608B and 608C to position the applicator 601.

  As shown in FIG. 49, applicator coordinates 625 of the heat treatment apparatus control circuit 609 can be displayed on the CRT display 612 so as to overlap the MRI image 622. However, the applicator coordinates 625 in the example of FIG. 49 are three-dimensional and two-dimensional coordinates with the reference point 608A as the origin. Since the coordinates of the focal point 607 are set based on the reference point 608A, the alignment of the applicator 601 and the treatment plan are performed according to the applicator coordinates 625. For example, the position of the focal point 607 is designated on the CRT display 612 via an input device 623 such as a light pen or a touch panel, and this information is stored in the heating device control circuit 609. At this time, the input device 623 such as a touch panel or a light pen on the CRT display 612 can be used by switching between the operation at the MRI coordinate 626 and the operation at the applicator coordinate 625, and any arbitrary image on the MRI three-dimensional image can be used. When a cross section is designated, it can be performed with MRI coordinates as before.

  The focal point 607 is also displayed on the MRI image 622 of the CRT display 612 as shown in FIG. The ultrasonic incident path 624 can also be displayed.

  When the coincidence between the position of the focal point 607 and the position of the tumor 606 stored in the built-in memory is detected, the heat treatment apparatus control circuit 609 instructs the drive circuit group 611 to start the ultrasonic irradiation, thereby starting the treatment. The Here, an MRI image of the affected part including the reference point 608A is taken immediately before the irradiation of the powerful ultrasonic wave every time, and the coincidence state between the reference point 608A and the coordinates of the MRI image can be confirmed. When the reference point 608A moves away from a point on the MRI coordinates initially determined by the movement of the patient such as respiratory movement, the heating device control circuit 609 controls the drive circuit group 611 to drive the ultrasonic transducer 602. To stop. In this operation, an MRI three-dimensional image including all the reference points 608A, 608B, and 608C is picked up, and if any of these three reference points moves away from the original point by a predetermined value or more, ultrasonic irradiation is performed. It may be to stop.

  Ultrasound irradiation is stopped at the time when it seems to be in the middle or the end of the initial treatment plan, and the progress of treatment is observed. This is performed by taking an MRI image around the tumor 606 and examining changes in the living body in the same manner as described above. During this time, the applicator 601 remains attached to the patient 603. Then, by subtracting the T2-weighted image data stored in the memory before the treatment and the current data, the heat-denatured region can be clearly confirmed, and the treatment has been performed sufficiently or is insufficient. Can determine if re-treatment is necessary. It is also possible to incorporate such a treatment effect determination step into the treatment plan from the beginning, and to automatically take MRI images around the tumor 606 every predetermined treatment time.

  When it is considered that the treatment has been completed, an MRI three-dimensional image inside the body is taken by the same operation as described above. At this time, a surface including a portion suspected of treatment failure is designated on the CRT display 612 via the input device 623, and, for example, an MRI two-dimensional image of the portion is displayed and examined in detail. When the portion (point or range) is indicated by the applicator coordinates 625 on the CRT display 612, the information is sent to the heating therapy apparatus control circuit 609, and the heating therapy apparatus control circuit 609 indicates the treatment leakage in the designated body. After controlling the phase control circuit group 610 so as to focus on the portion, the drive circuit group 611 is driven to add heat treatment.

  When it becomes possible to determine that the treatment has been sufficiently completed by determining the treatment effect by MRI, the operator ends the treatment. At this time, the MRI control circuit 614 can call up a history of treatment conditions from the memory and output a treatment record from the CRT display 612.

The reference example can be variously modified, and for example, a body cavity coil may be used as the transmission / reception RF coil 619. In addition, although a phased array is used for the ultrasonic transducer 602, an annular array may be used instead, or a method of moving the focus by mechanically moving the applicator 601 may be used.

  Also, as shown in FIG. 50, an ultrasonic probe 628 is inserted into an ultrasonic probe insertion hole 629 provided in the center or a part of the ultrasonic transducer 627, and this is connected to the ultrasonic diagnostic apparatus 630 to perform real time. In addition, an ultrasonic image inside the body may be observed. The ultrasonic probe 628 is configured to be able to slide and rotate in the front-rear direction. Then, the relative position between the ultrasonic probe 628 for obtaining an ultrasonic tomographic image and the focal point 607 of the therapeutic ultrasonic wave is obtained, and the focal position 607 is displayed on the ultrasonic image based on the information on the relative position, and further the MRI. The position of the ultrasonic tomographic image displayed at that time is indicated on the two-dimensional or three-dimensional in-vivo image obtained in step 1, and the ultrasonic tomographic image can be used in accordance with the previously set treatment plan. These methods are described in detail in JP-A-5-300910.

Further, the applicator 601 does not have to be a so-called upper approach that is mounted on the patient 603 from above as in the present reference example , and an applicator that is controlled by a mechanical arm (not shown) can be configured and used in the lower approach. Can do.

( 13th Reference Example )
FIG. 51 is a configuration diagram of the thirteenth reference example . First, the configuration of the applicator 631 in FIG. 51 will be described with reference to FIG. In this reference example , the ultrasonic transducer 632 has a fixed focal point, and a type that mechanically moves the focal point is used (see JP-A-63-99343). The applicator 631 stores an ultrasonic transducer 632 that emits therapeutic high-power ultrasonic waves, a coupling liquid 604 that guides high-power ultrasonic waves to the patient 603, a water bag 605 that seals the coupling liquid 604, and these. Housing 633. A plurality of applicator side reference points (explained here with two points) 638A and 638B are attached to the housing 633. These applicator-side reference points 638A and 638B are used to accurately match the applicator 631 with a plurality of subject-side reference points (explained here by two points) 639A and 639B, for example, as shown in FIG. As described above, the applicator side reference points 638A and 638B may be formed in a concave shape, and the convex object side reference points 639A and 639B may be fitted therein. As another configuration, as shown in FIG. 54, convex applicator reference points 641A and 641B may be fitted into concave object-side reference points 640A and 640B.

  The ultrasonic transducer 632 is obtained by cutting a single piezoelectric element into a spherical shell, and is vertically moved by a support rod 634 controlled by a transducer position control circuit 635 in a housing 633 filled with a coupling liquid 604. The movement and the swinging by the bearing 637 controlled by the vibrator position control circuit 635 are possible.

At the time of treatment, the applicator 631 is placed on the body surface of the patient 603 as in the twelfth reference example, and the water bag 605 is brought into contact with the skin of the patient 603 via an ultrasonic jelly or the like (not shown). After the focal point 607 is matched with the tumor 606 by the transducer position control circuit 635, the ultrasonic transducer 632 is driven by the drive circuit 636 to irradiate the powerful ultrasonic wave, and the treatment site matched with the focal point 607 is maintained at a high temperature. To treat.

Next, the positioning and MRI image imaging unit in this reference example will be described.

  First, the subject-side reference points 639A and 639B are attached to the patient 603 at positions where they are exactly coincident with the reference points 638A and 638B of the applicator 631. The subject-side reference points 639A and 639B are suitably disposable protrusions with strong adhesive force, and can be clearly depicted on the MRI image, and can be easily distinguished from biological substances. More preferably, a non-magnetic material is preferable. Specific examples include rubbers and resins. Next, the applicator 631 is mounted on the patient 603, and at this time, the positions of the reference points 638A, 638B and 639A, 639B are made to exactly match. The patient 603 thus set on the treatment table 620 and attached with the reference points 639A and 639B is subjected to the RF coil 619, the static magnetic field coil 617, and the gradient magnetic field coil by the table moving device 613 controlled by the MRI control circuit 614. 618 is fed into an imaging gantry (not shown).

Next, the MRI control circuit 614 activates the gradient magnetic field power source 616 and the transmission / reception circuit 615 according to a predetermined sequence (for example, T2-weighted imaging method) instructed from the console 621, and the applicator reference point 638A (reference point 608 of the twelfth reference example ). The three-dimensional image information in the patient 603 is stored in a memory (not shown). This three-dimensional information can be displayed on the CRT display 612 by the MRI control circuit 614.

The operation of aligning the focal point 607 of the ultrasonic transducer 632 with the position of the tumor 606 depicted in the MRI three-dimensional image and the method of performing the treatment plan are the same as in Reference Example 13. Also, the confirmation of the treatment status during the treatment and the processing after the treatment are the same as in Reference Example 13, but in this Reference Example 14, the position of the applicator 631 and the position of the patient 603 are physically fixed at a plurality of points. Therefore, even if the applicator 601 is once removed from the patient 603 during the treatment, it can be reliably returned to the original position.

In this reference example , two applicator-side reference points and two subject-side reference points are shown. However, it is also effective to provide three reference points to stabilize the position. is there. In the above description, the representative reference point is the origin of the applicator coordinates ((X, Y, Z) = (0, 0, 0)). However, any value can be set for (X, Y, Z). May be given.

As described above, according to this reference example , it is only necessary to align the applicator of the heat treatment apparatus and the subject during the ultrasonic heat treatment. Since it is not necessary to incorporate a special mechanism for detecting the relative position, accurate alignment can be performed even when the CT apparatus and the heat treatment apparatus are separately configured, and safety for the patient can be ensured. Cost can be reduced.

Block diagram showing the configuration of the first reference example Schematic diagram for explaining the irradiation procedure of intense ultrasound in the reference example Flow chart showing the irradiation procedure of intense ultrasound in the reference example The figure for demonstrating another irradiation procedure of the powerful ultrasonic wave in the reference example Block diagram showing the configuration of the second reference example The figure which shows the positional relationship and operation | movement of an ultrasonic probe and a vibrator | oscillator in the reference example The figure which shows the other example of the mechanism which makes the relative position of an ultrasonic probe and a vibrator variable. Shows a configuration in the case of using a two-dimensional array of third reference example The figure which shows the example of a CRT image display during the powerful ultrasonic irradiation treatment in the reference example Configuration diagram of the fourth reference example Explanatory drawing of the concept of movement in the reference example Schematic diagram for explaining motion correction at the time of temperature measurement by MRI in the reference example Flow chart showing the treatment procedure incorporating the motion correction method from the image in the reference example Schematic diagram showing the temporal flow when performing motion detection and temperature change detection on the reference image in the reference example Schematic diagram showing the temporal flow when performing motion detection and temperature change detection for the image obtained immediately before in the reference example The schematic diagram which shows the MRI pulse sequence of the point excitation (two-dimensional one-shot local excitation) which concerns on the Example of this invention . Schematic diagram showing the procedure of ultrasonic irradiation and data using point excitation in the same embodiment The figure which shows an example of the temperature display means in the case of the point excitation in the Example Schematic diagram illustrating the MRI sequence of line excitation according to the actual施例 Schematic diagram showing the procedure of ultrasonic irradiation and data processing using line excitation in the same embodiment The figure which shows an example of the temperature distribution display means in the case of the line excitation in the Example The schematic diagram which shows the procedure which determines a temperature measurement point from the temperature distribution in the Example. The treatment sequence diagram which performs temperature measurement and relaxation time emphasis signal measurement simultaneously according to an embodiment of the present invention MRI pulse sequence diagram for performing temperature measurement and relaxation time enhancement signal measurement in the same sequence according to an embodiment of the present invention Schematic diagram showing a point-excitation MRI pulse sequence according to an embodiment of the present invention (when three α ° pulses are used) The schematic diagram of the time flow in the case of feeding back the temperature measured at the time of treatment irradiation which concerns on the Example of this invention to treatment irradiation Schematic diagram showing an MRI pulse sequence of line excitation according to a fifth reference example Flow chart of control signals for computer control according to the reference example Schematic showing the control means of the applicator in the computer display according to the reference example Schematic diagram of position / angle detection means by encoder of hand probe type ultrasonic applicator according to the reference example Schematic diagram of position / angle detection means by optical gyro of the hand probe type ultrasonic applicator according to the reference example Schematic diagram of position / angle detection means by a TV camera of an ultrasonic applicator of the hand probe type according to the reference example Block diagram showing a sixth reference example Circuit diagram of main parts of drive circuit and received wave detection circuit for explaining means for detecting reflected signal from received signal in the reference example Block diagram showing a seventh reference example Circuit diagram of main part of received wave detection circuit for explaining means for detecting reflected signal from received signal in the reference example Block diagram showing an eighth reference example Block diagram showing the ninth reference example Configuration diagram of an ultrasound applicator of the first 10 of Reference Example AA 'sectional view of the ultrasonic applicator of FIG. Configuration diagram of an ultrasonic applicator of the Reference Example BB 'sectional view of the ultrasonic applicator of FIG. 11 Configuration Figure treatment device of the reference example of The 11 other configuration diagram of an ultrasonic applicator of the reference example of The 11 other configuration diagram of an ultrasonic applicator of the reference example of Configuration diagram of the twelfth reference example Configuration of applicator in the reference example Configuration diagram of ultrasonic transducer in the reference example The figure which shows the display screen on the CRT display in the same reference example 12 Another configuration diagram of the reference example Configuration diagram of thirteenth reference example Configuration of applicator in the reference example The figure which shows an example of how to provide the reference point in the reference example The figure which shows the other example of how to provide the reference point in the reference example

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Applicator 102 ... Piezoelectric element group 103 ... Patient 104 ... Water 105 ... Coupling membrane 106 ... Strong ultrasonic focus 107 ... Affected part (tumor) 108 ... Ultrasonic probe 109 ... Drive circuit 110 ... Applicator position detection device 111 ... Mechanical arm 112 ... Stage controller 113 ... Zθ stage 114 ... Xθ stage 115 ... Ultrasound image diagnostic apparatus 116 ... Digital scan converter 117 ... CRT 118 ... Auxiliary input device 119 ... System controller 110 ... Console 121 ... Water treatment circuit 122 ... XYZ stage 123 ... Zθφ stage 124 ... Instruction cursor 125 ... Heating point 126 ... Ultrasonic B-mode image 127 ... Ultrasonic addition C-mode image 128 ... Ultrasonic 3D image 129 ... Treatment block three-dimensional enlarged image 121 ... Static magnetic field carp DESCRIPTION OF SYMBOLS 122 ... Gradient magnetic field power supply 123 ... Transmission / reception circuit 124 ... Table moving apparatus 125 ... Work hole 126 ... Phase control circuit 201 ... Static magnetic field magnet 202 ... Excitation power supply 203 ... Subject 204 ... Gradient magnetic field coil 205 ... Sequence controller 206 ... Gradient magnetic field Coil driving circuit 207 ... Bed 208 ... High-frequency coil 209 ... Transmission unit 210 ... Duplexer 211 ... Reception unit 212 ... Data collection unit 213 ... Computer 214 ... Console 215 ... Image display 216 ... Ultrasonic applicator 217 ... Driving circuit group 218 ... Phase control circuit group 219 Power supply (for pulse generation) 221 Temperature display window 222 Temperature display window 223 Ultrasonic transducer position display 224 Setting focus 301 to 303 Rotation detection type encoder 304 to 306 Translation Decoding encoder 307 ... Grasping part 401 ... Ultrasonic applicator 402 ... Piezo element 403 ... Imaging ultrasonic probe 404 ... Flexible water bag 405 ... Patient 406 ... Treatment object 407 ... Ultrasonic propagation medium 408 ... Drive circuit 409 ... Control circuit 410 ... Reception wave detection circuit 411 ... Level detection circuit 412 ... Phase shift detection circuit 413 ... Ultrasonic diagnostic device 414 ... DSC 415 ... CRT display 416 ... Input unit 418 ... A / D converter 419 ... Memory 420 ... Oscillator 501 DESCRIPTION OF SYMBOLS ... Support body 502 ... Ultrasonic vibrator 503 ... Rotating shaft 504 ... Flexible film 505 ... Opening part 506 ... Focus 507 ... Rotation movement mechanism 511 ... Support body 512 ... Angle mechanism 513 ... Ultrasonic vibrator 514 ... Drive circuit group 515 ... Control circuit 516 ... Delay circuit group 517 ... Focus 518 ... Ultrasonic vibrator for image 519 ... Ultrasonic diagnostic apparatus 520 ... CRT display 521 ... Water control circuit 531 ... Support body 532 ... Ultrasonic vibrator 533 ... Strut 534 ... Moving groove 535 ... Focus 601 ... Applicator 602 ... Ultrasonic vibration Child 603 ... Patient 604 ... Coupling fluid 605 ... Water bag 606 ... Tumor 607 ... Focus 608A to 608C ... Reference point 609 ... Heat treatment device control circuit 610 ... Phase control circuit group 611 ... Drive circuit group 612 ... CRT 613 ... Table movement Apparatus 614 ... MRI control circuit 615 ... Transmission / reception circuit 616 ... Gradient magnetic field power supply 617 ... Static magnetic field coil 618 ... Gradient magnetic field coil 619 ... RF coil 620 ... Treatment table 621 ... Console 622 ... MRI image 623 ... Input device 624 ... Ultrasonic incident path 625 ... applicator coordinates 626 ... MRI 627 ... Ultrasonic transducer 628 ... Ultrasonic probe 629 ... Probe insertion hole 630 ... Ultrasonic diagnostic device 631 ... Applicator 632 ... Ultrasonic transducer 633 ... Housing 634 ... Support rod 635 ... Transducer position control circuit 636 ... Drive Circuit 637 ... Bearings 638A, 638B ... Applicator side reference point 639A, 639B ... Subject side reference point 640A, 640B ... Subject side reference point 641A, 641B ... Applicator side reference point

Claims (1)

A magnetic resonance diagnostic apparatus for collecting image information in a subject and recognizing a treatment target site in the subject;
Therapeutic energy irradiation means for performing treatment by irradiating the therapeutic energy to the site to be treated and heating it to cause thermal denaturation; and
A measurement site setting unit capable of arbitrarily setting a temperature measurement site during the therapeutic energy irradiation by the therapeutic energy irradiation unit;
Means for acquiring temperature information using local excitation by the magnetic resonance diagnostic apparatus for the temperature measurement part set by the measurement part setting means;
Based on the temperature information acquired by this means, when the temperature measurement part shows a predetermined temperature rise, the therapeutic energy irradiation means continues to irradiate the therapeutic energy, and the temperature measurement part is An ultrasonic therapy apparatus comprising: a control unit that controls to stop the irradiation of the therapeutic energy in the therapeutic energy irradiation unit when the temperature does not increase .

Images