Patent Publication Number: US-2010130858-A1

Title: Puncture Treatment Supporting Apparatus

Description:
TECHNICAL FIELD 
     The present invention relates to a puncture treatment supporting apparatus for drawing up a puncture operation plan by simulation and displaying the puncture operation proceedings. 
     BACKGROUND ART 
     Ultrasonic diagnostic apparatuses obtain a tomographic image of soft tissues in a living body using ultrasonic pulse reflection method. Ultrasonic diagnostic apparatuses are compact in size and inexpensive compared to other medial image diagnostic apparatuses, highly safe since there is no exposure to radiation such as X-rays, and has features such as being capable of imaging blood flow, thus are widely used, for example, in digestive organs departments, urology departments, and obstetrics and gynecology departments. 
     The ultrasonic diagnostic apparatus is used for inserting a puncture needle into an object while observing an ultrasonic image, obtaining a part of tumor cells for a sample using the puncture needle or cauterizing the tumor using an RF coil provided at the end point of the puncture needle. The probes to be used at this time are a biopsy type provided with a groove for inserting a puncture needle to a part of an array-type probe, or an adapter type that is an array-type probe in which an adapter for puncture is mounted. 
     In Patent Document 1, a technique is disclosed for constructing and displaying a tomographic image corresponding to an ultrasonic image in accordance with the position and the angle of a probe arbitrarily specified by an operator, from volume data regarding an object collected by a medical image diagnostic apparatus other than an ultrasonic diagnostic apparatus (such as an X-ray CT apparatus or an MRI apparatus). 
     While the operator develops a puncture plan in advance by imaging the position of a tumor in the body of an object, it is difficult to do so and to perform a puncture operation when the target region for the treatment is in a complicated region in the body of the object. 
     The objective of the present invention is to provide a puncture treatment supporting apparatus capable of performing a puncture simulation in advance, performing a puncture treatment in accordance with the simulation, and evaluating the treatment. 
     Patent Document 1: JP-A-2002-112998 
     DISCLOSURE OF THE INVENTION 
     Problems to be Solved 
     In order to achieve the above-described objective, the puncture treatment supporting apparatus of the present invention comprising: 
     an ultrasonic probe for transmitting/receiving ultrasonic waves to/from an object; 
     ultrasonic image construction means for constructing an ultrasonic image on the basis of the ultrasonic signals obtained by the ultrasonic probe; 
     volume data storing means for storing volume data of the object being imaged by a medical image diagnostic apparatus; 
     probe position/direction detecting means for detecting the position and direction of the ultrasonic probe; 
     tomographic image construction means for constructing from the volume data a tomographic image having the same cross-section as the ultrasonic image, using information on the position and direction of the ultrasonic probe; 
     display means for displaying the ultrasonic image and the tomographic image; and 
     puncture means for inserting a puncture needle into the object via the ultrasonic probe, 
     is characterized in comprising: 
     simulation image construction means for constructing a simulation image provided with a puncture guideline indicating the position and direction for inserting the puncture needle on the tomographic image, 
     wherein the display means displays the simulation image along with the ultrasonic image. 
     Also, the simulation image construction means synthesizes the puncture guidelines and the volume data, stores the synthesized data in the volume data storing means, and constructs the simulation image from the synthesized volume data using information on the position and direction of the ultrasonic probe. 
     Also, the simulation image construction means has: 
     puncture guideline creating means for creating the puncture guideline using the ultrasonic image or the tomographic image; and 
     volume data synthesizing means for synthesizing and storing the volume data and the puncture guideline, 
     and constructs a simulation image provided with the puncture guideline, from the synthesized volume data. 
    
    
     
       BRIEF DESCRIPTION OF THE DIAGRAMS 
         FIG. 1  shows a system configuration of the puncture treatment supporting apparatus related to the present invention. 
         FIG. 2  shows the detail of the puncture treatment supporting apparatus related to the present invention. 
         FIG. 3  shows the operation procedure of the present invention. 
         FIG. 4  shows the concept of a scale conversion related to the present invention. 
         FIG. 5  shows a display example related to the present invention. 
         FIG. 6  shows a display example related to the present invention. 
         FIG. 7  shows a display example related to the present invention. 
         FIG. 8  shows a display example related to the present invention. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, the system configuration of the puncture treatment supporting apparatus related to the present invention will be described using  FIG. 1 . 
     The puncture treatment supporting apparatus comprises: 
     a medical image diagnostic apparatus  102  such as an X-ray CT apparatus or an MRI apparatus; 
     a probe  103  for transmitting/receiving ultrasonic waves to/from an object  112 ; 
     a probe position sensor  105  formed together with the probe  103 ; 
     a source  106  placed in the vicinity of the object  112 , and 
     for detecting the movement of the probe position sensor  105  by a magnetic field, etc.; 
     an image processing device  101  for imaging the image data obtained from the medical image diagnostic apparatus  102  or the probe  103 ; and 
     a display unit  104  for displaying the image processed in the image processing device  101 . 
     Further, a central control device (not shown in the diagram) is provided in the image processing device  101 , and controls the respective components in the image processing device  101 . 
     Next, inner structure of the image processing device  101  will be described. The image processing device  101  is mainly formed by: 
     a first route for constructing an ultrasonic image on the basis of the echo signals outputted from the probe  103 ; 
     a second route for constructing a 3-dimensional image using the volume data outputted from the medical image diagnostic apparatus  102 ; 
     a third route for constructing a tomographic image having the same cross-section as the above-mentioned ultrasonic image using the volume data outputted from the medical image diagnostic apparatus  102 ; and 
     a fourth route for constructing a puncture simulation image using the volume data outputted from the medical image diagnostic apparatus  102 . A display processing device  111  performs processing of juxtaposing and displaying, or superimposing and displaying the images that are constructed in the respective routes, and displays the processed images. 
     Also, a process for detecting the position and direction of the probe  103  using the probe position sensor  105  and the source  106  will be described. The probe position sensor  105  detects magnetic signals generated from the source  106  to a 3-dimensional space. Then the position and direction of the probe position sensor  105  in a reference coordinate system formed by the source  106  are transmitted to the probe position/direction calculating unit  109 . The probe position/direction calculating unit  109  calculates a scan plane coordinate of the ultrasonic image from the transmitted position and direction. 
     Here, the first route for constructing an ultrasonic image will be described. The probe  103  is for transmitting/receiving ultrasonic waves to/from the object  112 , and has a plurality of transducers for generating ultrasonic waves and receiving echo signals. An ultrasonic image construction unit  107  converts the echo signals transmitted from the probe  103  into digital signals, and creates ultrasonic image data such as a black and white tomographic image (B-mode image) or a color flow mapping image (CFM image). The ultrasonic image data created in the ultrasonic image construction unit  107  are outputted to a display processing device  111 . The ultrasonic image constructed in the ultrasonic image construction unit  107  and displayed is a tomographic image. 
     Next, the second route for constructing a 3-dimensional image using the volume data of the medical image diagnostic apparatus will be described. The second route has a volume data storing unit  108  being connected to the medical image diagnostic apparatus  102  using a network, etc. and is for storing the volume data, and a 3-dimensional image construction unit  122  for creating 3-dimensional image data from the stored volume data using a method such as the volume rendering method. The 3-dimensional image data created in the 3-dimensional image construction unit  122  are outputted to the display processing device  111 . 
     Also, the 3-dimensional image construction unit  122  corresponds the coordinate of the volume data to the scan plane coordinate of the probe  103  detected in the probe position/direction calculating unit  109 , synthesizes a scan plane guide of the same cross-sectional position of the ultrasonic image to the 3-dimensional image data, and outputs the synthesized data. A scan plane guide is displayed on the 3-dimensional image displayed on the display unit  104 . Accordingly, an operator can recognize the cross-sectional position of the ultrasonic image 3-dimensionally. 
     Next, the third route for constructing a tomographic image having the same cross-section as the ultrasonic image using the volume data outputted from the medical image diagnostic apparatus  102  will be described. The third route has a volume data storing unit  108  for storing volume data, and a tomographic image construction unit  110  arranged by being connected to a cross-sectional position parameter adjusting unit  124  which is connected to the probe position/direction calculating unit  109 , and is for creating tomographic image data having the same cross-section position as the ultrasonic image imaged at the position of the probe  103  by an X-ray CT apparatus or an MRI apparatus. In concrete terms, the tomographic image construction unit  110  calculates the scan plane coordinate in the coordinate system of the tomographic image based on the scan plane coordinate calculated in the probe position/direction calculating unit  109 . Then the tomographic image construction unit  110  creates tomographic image data with respect to the part that the volume data and the scan plane are superimposed, from the coordinate data of the scan plane in the coordinate system of the volume data and the rotation angle around the XYZ-axis of the scan plane. The created tomographic image data are outputted to the display processing device  111 . 
     Next, the fourth route for creating the puncture simulation image using the volume data outputted from the medical image diagnostic apparatus  102  will be described. 
     The fourth route has a simulation image construction unit  100  for creating the puncture simulation image data using the volume data stored in the volume data storing unit  108 . The simulation image construction unit  100  will be described using  FIG. 2 . 
     The simulation image construction unit  100  has: 
     a volume data calculating unit  131  for performing the scaling or position adjustment of the volume data outputted from the volume data storing unit  108 ; 
     an ultrasonic image storing unit  130  for storing the ultrasonic image obtained in the ultrasonic image construction unit  107 ; 
     a puncture guideline creating unit  132  for creating the puncture guideline using the positional information obtained from an input device  121  or the ultrasonic image storing unit  130 ; 
     a volume data synthesizing unit  133  for synthesizing the processed volume data and the puncture guideline; and 
     a tomographic image construction unit  134  for creating the simulation image data having the same cross-sectional position as the ultrasonic image being imaged in the position and direction of the probe  103 . 
     The tomographic image construction unit  134  calculates the scan plane coordinate in the coordinate system of the tomographic image based on the scan plane coordinate calculated by the probe position/direction calculating unit  109 . Then the tomographic image construction unit  134  creates the simulation image data with regard to the part that the volume data and the scan plane are synthesized, from the coordinate data of the scan plane in the coordinate system of the synthesized volume data and the rotation angle around the XYZ-axis of the scan plane. 
     A plurality of memories are mounted in the volume data storing unit  108 , and are capable of storing a plurality of volume data. Therefore, the plurality of volume data obtained in different times can be stored. 
     Next, operation procedure of the present invention will be described using the flow chart in  FIG. 3 . 
     (Step  201 ) 
     First, the volume data calculating unit  131  converts the volume data into the data of a blood vessel, tumor, bone or air that is being enhanced. Generally, the volume data of an X-ray CT apparatus or an MRI apparatus being collected after injecting contrast medium are collected in a plurality of phases after injecting the contrast medium, and the enhanced region is different in each phase. For example, in the case of a liver, while a tumor is enhanced and is visualized in clarity in an arterial phase wherein the most contrast medium flows in an artery, the blood vessel becomes difficult to see. On the other hand, while the tumor is hard to see in a portal wherein the most contrast medium flows in the portal vein, the blood vessel can be clearly identified. 
     The volume data calculating unit  131  processes the volume data stored in the volume data storing unit  108  using a method such as a threshold value method or region growing method, with respect to each phase so that more range of the blood vessel, tumor, bone or air can be identified. Any method can accurately extract the region in the case that the difference in luminance is clear between the respective tissues and the surrounding tissues. In the case that the region cannot be extracted, the operator may extract it using the input device  121 . Then the volume data calculating unit  131  processes the volume data by coloring the region of the extracted blood vessel or tumor, etc. 
     (Step  202 ) 
     Next, the volume data calculating unit  131  calculates the standard coordinate and the radius of a circumscribed sphere in the region extracted by the volume data. The method for calculating the standard coordinate and the radius of the circumscribed sphere will be omitted since it is a commonly known technique. The central position of the circumscribed sphere is the position to be a target for the puncture operation. Also, the size of the radius is to be an index for determining the cauterization time upon performing the radiofrequency ablation. 
     (Step  203 ) 
     Next, the association of the coordinate systems is performed between an abdominal model of a human body to be used in place of an object upon simulation and the volume data created by the volume-data calculating unit  131 . 
     First, calibration is performed to make the standard coordinate (or the original point of the coordinate) of the abdominal model coincides with the standard coordinate (or the original point of the coordinate) of the volume data, using the abdominal model of the human body to be used in place of the object. Then the direction for setting the abdominal model is adjusted so that the coordinate system of the abdominal model is coincided with the direction of a unit vector of the coordinate system of the volume data. 
     In the case that there is a difference of body size between the abdominal model and the object to be the target for the puncture operation stored in the volume data, the volume data calculating unit  131  performs scale conversion between the coordinate system of the abdominal model and the coordinate system of the volume image data. A scale conversion matrix is used to perform the scale conversion. 
     Here, a conceptual diagram of the scale conversion is shown in  FIG. 4 . In  FIG. 4 , the diagram shown in the upper side illustrates an abdominal model of a human body formed approximately in circular cylinder, and the diagram shown in the lower side illustrates the volume data of the abdomen in the object obtained by an X-ray CT apparatus or an MRI apparatus. 
     First, a horizontal width Xo, a vertical width Yo and a length Zo in the body axial direction of a waste line of the abdominal model are inputted to the volume data calculating unit  131  using the input device  121 . Next, the volume data calculating unit  131  extracts the body surface of the volume data using a method such as the threshold method, and calculates a horizontal width Xp, a vertical width Yp and a length Zp in the body axial direction. Then using the above-calculated data, the following matrix is created and set as a scale conversion matrix S. 
     
       
         
           
             
               
                 
                   S 
                   = 
                   
                     [ 
                     
                       
                         
                           
                             Xp 
                             / 
                             Xo 
                           
                         
                         
                           0 
                         
                         
                           0 
                         
                         
                           0 
                         
                       
                       
                         
                           0 
                         
                         
                           
                             Yp 
                             / 
                             Yo 
                           
                         
                         
                           0 
                         
                         
                           0 
                         
                       
                       
                         
                           0 
                         
                         
                           0 
                         
                         
                           
                             Zp 
                             / 
                             Zo 
                           
                         
                         
                           0 
                         
                       
                       
                         
                           0 
                         
                         
                           0 
                         
                         
                           0 
                         
                         
                           1 
                         
                       
                     
                     ] 
                   
                 
               
               
                 
                   [ 
                   
                     Formula 
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     The calibration correction data and the scale conversion matrix S obtained by the calibration above are to be stored in the volume data calculating unit  131 . 
     In this way, the volume data calculating unit  131  is capable of coinciding the standard coordinates of the abdominal model of the human body and the volume data. Also, adjustment can be made even when there is a difference in body size between the abdominal model and the object. 
     (Step  204 ) 
     Next, the simulation of the puncture operation is performed applying the probe  103  onto the abdominal model. The operator sets a cross mark on the central position of the tumor using the input device  121 , while observing whether the central position of the tumor is included in the cross-section of the simulation image being calculated by the tomographic image construction unit  134 . Then the volume data calculating unit  131  adds the cross mark data at the position of the volume data corresponding to the cross mark set in the simulation image. 
     Next, the operator determines the position and direction for inserting the puncture needle while observing the simulation image, and creates the puncture guidelines by the puncture guideline creating unit  132 . In concrete terms, the operator specifies two points on a 3-dimensional image  401  or a simulation image  402  displayed on the display unit  104  using the input device  121 , and the positional information having the two specified points as the end is inputted to the puncture guideline creating unit  132 . Then the puncture guideline creating unit  132  creates the puncture guideline (position, length and direction) from the specified two points of the positional information. The puncture guideline created in the puncture guideline creating unit  132  is converted into a 3-dimensional coordinate, and stored in the volume data synthesizing unit  133  in a form corresponded to the volume data. 
     Also, as another method, the puncture guideline creating unit  132  creates a puncture guideline using luminance information of the ultrasonic image. It is created by inserting the puncture needle into the abdominal model, imaging an ultrasonic image which includes the puncture needle using the probe  103 , and storing the imaged ultrasonic image in the ultrasonic image storing unit  130 . The puncture guideline creating unit  132  creates the puncture guideline using the luminance information of the stored ultrasonic image. 
     Here, a method for creating the puncture guideline using luminance information of the ultrasonic image will be described in detail. In the abdominal model, the outward form is a simulated abdomen of a human body, and the inside thereof has a homogeneous material and tenderness being similar to the abdomen of a human body. The ultrasonic image imaged while the probe  103  is applied onto the abdomen model is homogeneous and low in luminance. In the case of inserting the puncture needle into the abdomen model, the puncture needle in the ultrasonic image has high luminance. Given this factor, the puncture guideline creating unit  132  creates a binary image by binarizing the ultrasonic image by high luminance and low luminance. Then the puncture guideline creating unit  132  creates a puncture guideline (position, length and direction) extracted as a high luminance part of the binary image as, for example, a green colored image data. The detected puncture guideline is converted into a 3-dimensional coordinate, and stored in the volume data synthesizing unit  133  in a form being corresponded to the volume data. By using the volume data synthesized with the guideline by the volume data synthesizing unit  133 , a simulation data having the same cross-sectional position as the ultrasonic image imaged in the same position and direction as the probe  103  is created. Accordingly, the state of the puncture needle being inserted is displayed on the simulation image as a green colored image. 
       FIG. 5  is a display example of the display unit  104 . The display unit  104  displays an ultrasonic image  400  created in the above-described first route, a 3-dimensional image  401  created in the above-described second route, and a simulation image  402  created in the above-described fourth route. A scan guide  403  indicates the cross-sectional position of the simulation image  402  being calculated by the tomographic image construction unit  134 . The display processing device  111  can select and display these images. On the simulation image  402 , a blood vessel  404 , a tumor  405 , a central position of the tumor  406  and a puncture guideline  407  for determining the position and direction to insert the puncture needle, and an acoustic shadow  408  indicating a part wherein the ultrasonic image can not be constructed very well due to the bone or air in the body of the object, are displayed. Also, the display unit  104  displays a column  409  for displaying the radius of a tumor which is a target, a button  410  for selecting whether to display the cross-section orthogonal to the simulation image or not, a button  411  for selecting whether to display an acoustic shadow  408  or not, a puncture guideline inputting column  412  for inputting the puncture guideline to display the place for performing the puncture by the angle with respect to the probe  103 , etc., and a scroll bar  413  for inputting how to move the position of an organ in accordance with breathing of the object. Input information of the above-mentioned buttons and columns are given by the input device  121 . The conventional technique in regard to the acoustic shadow is disclosed in WO2004/0984141A1. 
     At this time, as shown in  FIG. 5 , the tumor  405 , the blood vessel  404  or the acoustic shadow  408  are displayed on the simulation image  402 . In the case of creating the guideline  407  using the input device  121 , the operator needs to pay attention to, for example:
         (a) set the tumor  405  or the blood vessel  404  etc. not to be hidden by the acoustic shadow  408 ,   (b) set the puncture guideline  407  to pass through the central point of the tumor  405 , and   (c) set the puncture guideline  407  not to pass through the blood vessel  404 .       

     As mentioned above, the puncture needle can be inserted into the abdomen model by which the object is simulated, having the simulation image  402  as a guide. The operator can perform puncture on the model as if performing it on the actual object. This is also useful for the puncture training for an inexperienced operator. 
     Also, the puncture guideline data detected in a puncture guideline creating unit  132  is converted into a 3-dimensional coordinate, and the 3-dimensional image construction unit  122  constructs a 3-dimensional image data provided with a puncture guideline  415 . In the 3-dimensional image  401  displayed on the display unit  104 , the body surface is displayed translucently, and the blood vessel  404 , the tumor  405 , the scan plane guide and the puncture guideline  415  are 3-dimensionally displayed on the inside of the body. 
     In puncture treatment, while the position of the bone does not move but organs move by breathing of the object, and the position of the acoustic shadow varies accordingly. Given this factor, in the present step, the cross-sectional position parameter adjusting unit  124  changes the cross-sectional position of the simulation image  402  created by the tomographic image construction unit  134 , by sliding the scroll bar  513  in  FIG. 5  using the input device  121 . For example, by sliding a sliding bar  413  coordinating with the breathing, the tomographic image construction unit  134  can change the cross-sectional position of the simulation image  402 . Also, by setting the sliding bar  413  using the input device  121  so as to periodically repeat parallel translation, for example, once in every 10 seconds, the tomographic image construction unit  134  can periodically change the cross-sectional position of the simulation image  402 . 
     Also, in the present step, as shown in  FIG. 6 , the puncture guideline cross-sectional image  502  including the puncture guideline  407  can be displayed which is the orthogonal cross-section to the simulation image  501  on the left side. In concrete terms, the cross-sectional position parameter adjusting unit  124  adjusts the cross-sectional position parameter so as to rotate the volume data having the puncture guideline  407  as the central axis, based on the position and direction of the puncture guideline  407 . The tomographic image construction unit  134  constructs a puncture guideline cross-sectional image  502  using the adjusted cross-sectional position parameter and the volume data. In addition, while the volume data is rotated having the puncture guideline  407  as the central axis, the central axis of the probe  103  or the blood vessel  404  may also be used. 
     (Step  205 ) 
     Next, in step  204 , the operator performs the puncture operation while observing the set puncture guideline  407 . 
     The ultrasonic image constructed in the first route is a real-time ultrasonic image  400  obtained in real time. The simulation image  402  constructed in the fourth route is the same cross-section as the real-time ultrasonic image  400  and includes the puncture guideline  407 . The operator secures the probe  103 , confirming that the puncture guideline  407  is displayed on the simulation image  402  toward the direction of the central position of the tumor, or that the puncture guideline  407  is displayed from a start-point to an end-point. Then the operator inserts the puncture needle into the object while observing the ultrasonic image  400 , and secures the puncture needle upon reaching the central position of the tumor  405 . The operator then performs the operation such as collecting a part of the tumor cells or cauterizing the tumor using an RF coil provided at the end of the puncture needle. 
     (Step  206 ) 
     After the puncture operation, volume image data after the treatment are obtained. The volume data before the treatment and the volume data after the treatment are stored in the volume data storing unit  108 . Then the tomographic image construction unit  110  creates the tomographic data using each volume data, and displays them on the display unit  104 . 
     Here, the operator searches for, for example, a bifurcation of a blood vessel in the vicinity of the tumor, and specifies the reference point using the input device  121 . The volume data storing unit  108  compares the tomographic images created by the volume data before and after the treatment, and the respective coordinates are made to correspond to each other on the basis of the reference point. Conversion matrix M expressing the relative positional relationship between the volume data before the treatment and after the treatment is calculated according to the following formula. 
     
       
         
           
             
               
                 
                   M 
                   = 
                   
                     [ 
                     
                       
                         
                           1 
                         
                         
                           0 
                         
                         
                           0 
                         
                         
                           dX 
                         
                       
                       
                         
                           0 
                         
                         
                           1 
                         
                         
                           0 
                         
                         
                           dY 
                         
                       
                       
                         
                           0 
                         
                         
                           0 
                         
                         
                           1 
                         
                         
                           dZ 
                         
                       
                       
                         
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                     ] 
                   
                 
               
               
                 
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     Here, both of the volume data are assumed to be imaged from the direction of the object. The present formula uses the parallel translation model, and dX, dY and dZ are the values to be calculated based on the reference-point coordinate of the volume image data before the treatment and the volume image data after the treatment. In this way, the coordinate system between the volume data are corresponded to each other in the volume data storing unit  108  using the conversion matrix M. Then the tomographic image construction unit  110  constructs two tomographic images from the two volume data so as to synchronize with the position of the probe  103 , and displays them on the display unit  104 . 
     Here, a method for constructing two tomographic images using two volume data obtained at the different times will be concretely described. The operator moves the probe  103  so that a specified cross-sectional image of the object is displayed on the first tomographic image being constructed using the first volume data. Then the operator turns off a synchronization button using the input device  121  at a point that the specified cross-sectional image is displayed on the first tomographic image on the display unit  104 . When the synchronization button is turned off, the cross-sectional position parameter adjusting unit  124  stops to transmit the information on the position and direction of the probe  103  calculated by the probe position/direction calculating unit  109  to the tomographic image construction unit  110 . Consequently, the first tomographic image constructed in the tomographic image construction unit  110  stops operating in compliance with the movement of the probe  103 , and the first tomographic image comes to rest at the state on which the specified cross-sectional image is being displayed. 
     Also, the operator moves the probe  103  so that the specified cross-sectional image of the object is displayed on the second tomographic image being constructed using the second volume data. This specified cross-section is the same as the specified cross-section being displayed on the first tomographic image. Then the operator turns off the synchronization button using the input device  121  when the specified cross-sectional image is displayed on the second tomographic image on the display unit  104 . When the synchronization button is turned off, the cross-sectional position parameter adjusting unit  124  stops to transmit the information on the position and direction of the probe  103  calculated by the probe position/direction calculating unit  109  to the tomographic image construction unit  110 . Consequently, the second tomographic image constructed by the tomographic image construction unit  110  stops operating in compliance with movement of the probe  103 , and the second tomographic image comes to rest at the state on which the specified cross-sectional image is being displayed. 
     Then the operator moves the probe  103  so that the specified cross-section displayed on the first cross-sectional image and the second cross-sectional image are to be displayed on the ultrasonic image constructed in the first route. When the specified cross-section is displayed on the ultrasonic image, the probe  103  is fixed, and the respective synchronization buttons are turned on using the input device  121 . 
     The cross-sectional position parameter adjusting unit  124  transmits the information on the position and direction of the probe  103  calculated by the probe position/direction calculating unit  109  to the tomographic image construction unit  110 . Then the tomographic image construction unit  110  constructs the first tomographic image and the second tomographic image having the same cross-sectional position as the ultrasonic image being imaged in the position and direction of the probe  103 , using the first volume data and the second volume data. Accordingly, the first tomographic image and the second tomographic image can be juxtaposed and displayed on the display unit  104 . It can be displayed in the same manner in the case of having three or more volume image data. 
       FIG. 7  shows a display example of the display unit  104  in the present step. An synchronization button  801  is a button for the operator to set the synchronized condition or non-synchronized condition. Four tomographic images are to be created here using four volume data acquired at different times. The operator makes only one tomographic image being deviated from the specified image including the bifurcation of the blood vessel, etc. out of the four displayed tomographic images to be synchronized with the probe  103 , and makes the other three tomographic images to remain in non-synchronized condition. Then the probe  103  is moved to the position at which the same cross section as the specified image of the tomographic image synchronizing with the probe  103  is displayed. The probe  103  is then secured, the synchronization button is turned on using the input device  121 , and the cross-sectional position parameter adjusting unit  124  sets the four tomographic images in the synchronized condition. Accordingly, the cross-sectional position parameter adjusting unit  124  is capable of adjusting the cross-sectional position by selecting one tomographic image out of four tomographic images. 
     As mentioned above, the present invention is capable of performing the coordination of a plurality of tomographic images. The coordination of the coordinate system can be independently performed with respect to each volume data, thus the present invention can be applied to the case that the number of volume data is increased. In clinical practice, a plurality of tomographic images are often juxtaposed and displayed using the volume data obtained in arterial phase before the treatment, portal phase before the treatment, arterial phase after the treatment and portal phase after the treatment. 
       FIG. 8  shows another display example of the display unit  104  in the present step. While the plurality of tomographic images are displayed in the display pattern of  FIG. 7 , a plurality of simulation images may also be displayed in the same manner. In concrete terms, the operator moves the probe  103  so that the puncture guideline  407  is displayed on the simulation image constructed using each of the volume data. Then the operator turns off the synchronization button using the input device  121  when the puncture guideline  407  is displayed on the display unit  104 . When the synchronization button is turned off, the cross-sectional position parameter adjusting unit  124  stops to transmit the information on the position and direction of the probe  103  calculated by the probe position/direction calculating unit  109  to the tomographic image construction unit  134 . Consequently, the first tomographic image constructed by the tomographic image construction unit  134  stops operating in compliance with the movement of the probe  103 , and the first tomographic image comes to rest at the state on which the specified cross-sectional image is being displayed. Accordingly, as shown in  FIG. 8 , the display unit  104  is capable of displaying the simulation images  701  having the different time phases, upon drawing out the treatment plan or during the operation. 
     (Step  207 ) 
     The operator can compare the tomographic image before the treatment and the tomographic image after the treatment displayed on the same cross-section, and evaluate the treatment effect on the puncture operation cross-section. If the tomographic images before and after the treatment are superimposed and displayed, correspondent relationship between the treated area and non-treated area can be easily recognized. As for the superimposing method, variety of methods such as translucent synthesis by the alpha blending method and a method for extracting contours and synthesizing can be used. If it is judged that the treatment is insufficient in the treatment judgment process, it will be useful to extract the region to be retreated on the CT volume image data and stored the data, for performing retreatment by going back to step  201 . 
     The present information is not intended to be limited in the above embodiments, and various changes may be made without departing from the scope of the invention. For example, in step  204 , imaging and displaying the ultrasonic image of the abdominal model is not fundamental. In the case of not imaging the ultrasonic image of the abdominal model, the position or direction for inserting the puncture guideline may be inputted on the display screen using the input device  121 .