Abstract:
A diagnostic support system by which anatomical charts can be referred to easily by a simple operation with no need to store image data representing anatomical charts in each medical facility. This system includes a client terminal for transmitting image data, which represents a medical image obtained by imaging intended for diagnosis, and information on an examination utilizing the medical image to the database server, retransmitting the information on the examination to the database server when requesting anatomical chart data, and displaying an image including the anatomical chart based on the anatomical chart data received from the database server; and a database server for recording the received image data etc. in a first recording medium, and retrieving corresponding anatomical chart data from a second recording medium, in which plural kinds of anatomical chart data are recorded, to transmit the retrieved anatomical chart data to the client terminal.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a diagnostic support system of providing information required for diagnosis, from a data center for centrally storing medical data obtained in plural medical facilities, to the respective medical facilities. Furthermore, the present invention relates to a diagnostic support method used in such a diagnostic support system. 
     Description of a Related Art 
     Conventionally, in medical facilities such as clinics of general practitioners and hospitals, medical images have been taken using medical image taking apparatuses utilizing radiation (X-ray, α-ray, β-ray, γ-ray, electron beam, ultraviolet light, etc.), ultrasonic wave, MR (magnetic resonance), or the like. Such medical images are required to be stored in order to know the changes in medical conditions of patients, and required to be stored in a predetermined period by law. Accordingly, in the medical facilities, it is necessary to store a vast amount of medical images. Conventionally, films on which medical images are taken, or the like have been stored, and thereby, securing of storage space, management work, and retrieval work of medical images have imposed heavy burdens on the medical facilities. 
     In recent years, the digitization of medical image taking apparatuses has been proceeding, and the storage space can be reduced, and the management work and the retrieval work can be saved by recording medical images as image data in optical disks, magnetic disks, or the like. However, since one sheet of medical image is represented by a vast amount of image data, even if they are recorded in optical disks, a considerable number of optical disks are required to store medical data in a predetermined period. 
     Accordingly, a medical image central management system by which image data obtained in plural medical facilities are centrally stored in a database server provided in a data center apart from the medical facilities, and thereby, the necessity for the respective medical facilities to independently store recording media in which medical data have been recorded is eliminated and the space or costs for securing the space can be reduced is realized. 
     On the other hand, in order to use as an object of comparison when a taken medical image is unclear, or when explaining a taken radiation image to a patient, there is a demand to refer to an anatomical chart depicted as an illustration. In order to refer to anatomical charts easily by a simple operation, a system of referring to anatomical charts recorded as digital signals is desired. 
     As a related technology, JP-A-2002-263101 discloses an ultrasonic diagnostic apparatus capable of displaying an ultrasonic image with a reference image showing the interior of a living body. In this ultrasonic diagnostic apparatus, an appropriate anatomical chart image can be automatically selected from an anatomical chart DB (database) based on the probe coordinate position, body proportion information, and other information. However, because image data representing all anatomical charts is vast in amount, it is not efficient that the ultrasonic diagnostic apparatus installed in each medical facility retains image data representing all anatomical charts. 
     Further, in JP-A-2002-263101, there described that the anatomical chart DB may be formed substantially by an external storage device such as a CD-ROM, however, a considerable number of CD-ROMs are required to store image data representing all anatomical charts. 
     SUMMARY OF THE INVENTION 
     In view of the above described points, an object of the present invention is to provide a diagnostic support system and method by which anatomical charts can be referred to easily by a simple operation with no need to store image data representing anatomical charts in each medical facility. 
     In order to solve the above described problems, a diagnostic support system according to an aspect of the present invention is a diagnostic support system formed by connecting a client terminal provided in a medical facility and a database server provided in a data center via a network, the system comprising: a client terminal for transmitting image data which represents a medical image obtained by imaging intended for diagnosis, and information on an examination utilizing the medical image to the database server, retransmitting the information on the examination utilizing the medical image to the database server when requesting anatomical chart data representing a desired anatomical chart, and displaying an image including the anatomical chart based on the anatomical chart data received from the database server; and a database server for recording the image data and the information on the examination, which are received from the client terminal, in a first recording medium, and retrieving corresponding anatomical chart data from a second recording medium, in which plural kinds of anatomical chart data are recorded, based on the received information on the examination to transmit the retrieved anatomical chart data to the client terminal when anatomical chart data is requested. 
     Further, a diagnostic support method according to an aspect of the present invention is a diagnostic support method to be used in a diagnostic support system formed by connecting a client terminal provided in a medical facility and a database server provided in a data center via a network, the method comprising the steps of: (a) transmitting image data, which represents a medical image obtained by imaging intended for diagnosis, and information on an examination utilizing the medical image from the client terminal to the database server; (b) recording the received image data and information on the examination in a first recording medium in the database server; c) retransmitting the information on the examination utilizing the medical image from the client terminal to the database server when requesting anatomical chart data representing a desired anatomical chart; (d) retrieving corresponding anatomical chart data from a second recording medium, in which plural kinds of anatomical chart data are recorded, based on the received information on the examination in the database server when anatomical chart data is requested; (e) transmitting the retrieved anatomical chart data from the database server to the client terminal; and (f) displaying an image including the anatomical chart in the client terminal based on the anatomical chart data received from the database server. 
     According to the present invention, the information on the examination utilizing the medical image is retransmitted from the client terminal to the database server when requesting the anatomical chart data representing a desired anatomical chart, and the corresponding anatomical chart data is retrieved from the second recording medium, in which plural kinds of anatomical chart data are stored, based on the received information on the examination in the database server, and thereby, a diagnostic support system and method by which the anatomical chart can be referred to easily by a simple operation with no need to store the image data representing anatomical charts in each medical facility can be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram showing a configuration of a diagnostic support system according to one embodiment of the present invention; 
         FIG. 2  is a block diagram showing the configuration including a radiation image taking apparatus used in the one embodiment of the present invention; 
         FIG. 3  is a block diagram showing the constitution of a client terminal; 
         FIG. 4  is a block diagram showing the constitution of a database server; 
         FIG. 5  is a flowchart showing the operation of the diagnostic support system in the embodiment; 
         FIG. 6  is a flowchart showing the operation of the diagnostic support system in the embodiment; 
         FIG. 7  shows an example of an anatomical chart retrieval table recorded in an anatomical chart database; and 
         FIG. 8  shows a parallel display screen in which a radiation image and an anatomical chart are displayed side by side. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, the best mode of the present invention will be described in detail by referring to the drawings. The same reference numerals are assigned to the same component elements and the description thereof will be omitted. 
       FIG. 1  is a schematic diagram showing a configuration of a diagnostic support system according to one embodiment of the present invention. As shown in  FIG. 1 , this diagnostic support system includes plural clinics  10  as examples of medical facilities which are connected to a data center  20  via a network  30  such as a dedicated line, a public switched telephone network (PSTN), the Internet, or the like. 
     In the respective clinics  10 , imaging modalities  11  such as radiation image taking apparatuses or ultrasonic diagnostic apparatuses, client terminals  12  to which medical data such as image data representing medical images is inputted from the imaging modalities  11  for transferring the data to the data center  20 , firewalls (FW)  13  for preventing unauthorized access, printers  14  for printing out medical images on films or the like, etc. are connected via local area networks (LANs) to one another. 
     In the clinic  10 , patient attribution information and examination attribution information are inputted by an operator or from another terminal, and imaging of an examinee using the imaging modality  11  is performed according to an instruction by the operator based on such information. Here, the patient attribution information corresponds to information representing name of patient, ID number, date of birth, age, sex, etc. Further, the examination attribution information corresponds to information representing date of examination, date of consultation, imaging menu, part to be examined, image feature, etc. The imaging menu includes parts to be imaged as targets of imaging such as cephalic part, cervical part, and abdominal part, and imaging method as imaging directions toward a patient such as front and side. The part to be examined is thoracic part, thoracoabdominal part, four limbs, lumber spine, etc. as targets of examination. 
     In the embodiment, the client terminal  12  transmits an information request signal based on the imaging menu, the part to be examined, the image feature, etc. included in the examination attribution information, and downloads anatomical chart data used for diagnosis from the data center  20 , and thereby, space required for storing anatomical chart data can be reduced in the clinic  10 . 
     In the data center  20 , an authentication server  21  for authenticating access from client terminals  12 , an authentication database (DB)  22  for recording user information required for authentication, a firewall (FW)  23  for preventing unauthorized access, a database server  24  for managing the medical data transmitted from the client terminals  12 , a recording medium such as a hard disk in which a medical database (DB)  25  for accumulating the medical data is recorded, and a recording medium such as a hard disk in which an anatomical chart database (DB)  26  for storing anatomical chart data and an anatomical chart retrieval table are recorded are provided. In the embodiment, the authentication server  21  is provided within the data center  20 , however, the authentication server  21  may be provided outside of the data center  20 . 
     In the embodiment, the database server  24  retrieves anatomical chart data used for diagnosis from the anatomical chart database  26  based on the imaging menu, part to be examined, or image feature included in the information request signal transmitted from the client terminal  12  and transmits the data to the client terminal  12 , and thereby, space required for storing anatomical chart data is reduced in the clinic  10 . 
     Anatomical chart filenames are given to data files in anatomical chart data stored in the anatomical chart database  26 . Further, in the anatomical chart retrieval table, the imaging menu, the part to be examined, or the image feature, and an anatomical chart filename, and alpha channel information representing degree of transparency when an anatomical chart is displayed while being superimposed on a medical image are associated. 
     Next, the case of using a radiation image taking apparatus as the imaging modality  11  to generate image data will be described by referring to  FIG. 2 . As shown in  FIG. 2 , the radiation image taking apparatus includes an imaging device  40  for recording a radiation image on a recording sheet  1  by performing imaging by applying radiation to an examinee, and an image reading device  50  for photoelectrically reading information such as the radiation image recorded on the recording sheet  1 , and generating image data and image-associated information associated with the radiation image. The recording sheet  1  is coated with a photostimulable phosphor material, and information on a subject is recorded thereon by applying radiation thereto. The photostimulable phosphor material (accumulative phosphor) is a material in which, when applied with radiation, part of radiation energy is accumulated, and then, when applied with excitation light such as visible light, photostimulably emits light according to the accumulated energy. 
     The imaging device  40  includes a taking position elevating mechanism  41  for elevating the taking position in the examinee by finely adjusting the position of the recording sheet  1  set in a predetermined position to move upward or downward, a taking base  42  for positioning the feet of the examinee, a radiation generating unit  43  for applying radiation to the examinee, and an interface  44  to which control signals are inputted from the client terminal  12 . 
     The image reading device  50  scans the surface of the recording sheet  1  set in a predetermined position with a light beam outputted from a laser source  51  and passing through the light scanning unit  52 . By the scanning, the light beam is applied to the recording sheet  1 , and photostimulably emitted light is generated in an amount of light depending on the radiation image information that has been accumulatively recorded from the location applied with the light beam. The photostimulably emitted light is photoelectrically detected by a photomultiplier  53 , outputted as analog signals, amplified by an amplifier  54 , and digitized by an A/D converter  55 . Further, a barcode attached to a cassette in which the recording sheet  1  is stored is read by a barcode reader  56 , and the read barcode information is used as image-associated information corresponding to patient attribution information and examination attribution information. Thus generated image data and image-associated information are transmitted from an output unit  57  via a LAN to the client terminal  12 . 
     The client terminal  12  controls the imaging device  40  in response to the instruction by the operator, and the image data and the image-associated information are inputted from the image reading device  50  and temporarily stored there. In the client terminal  12 , image processing can be performed on the image data, or images for diagnosis can be displayed based on the image data and the image-associated information on a display or the like. Note that, because a vast amount of image data are daily accumulated, they are stored not for a long period in the clinic, but transferred to the data center apart from the clinic and stored there. Thereby, in the clinic, space for storing recording media in which medical data have been recorded, or costs for securing the space can be reduced. 
       FIG. 3  is a block diagram showing the constitution of the client terminal. The client terminal  12  includes an input unit  61  used for inputting the patient attribution information, the examination attribution information and various kinds of instructions, a barcode reader  62  for reading a barcode attached to a cassette in which the recording sheet  1  is stored, a display unit  63  for displaying images for diagnosis or the like, and a processing unit  120 . The medical images read by the image reading device  50  ( FIG. 2 ) are correlated with the patient attribution information and the examination attribution information, which are stored in the client terminal  12 , based on the barcode information read from the cassette using the barcode reader  62  in advance before taking. 
     The processing unit  120  includes a central processing unit (hereinafter, referred to as “CPU”)  121 , a memory  122  for temporarily storing inputted image data, image-associated information and anatomical chart data, a hard disk  123  as a recording medium, a hard disk control unit  124 , a DVD drive  125  for performing writing and reading on a DVD (digital versatile disk), and a network interface  126  for connection to a LAN. These parts  121  to  126  are connected to one another via a bus line. 
     Furthermore, the processing unit  120  includes interfaces  127  and  128 . The CPU  121  is connected via the interface  127  to the input unit  61  such as a keyboard or mouse and the display unit  63  such as a CRT display, and connected via the interface  128  to the imaging device  40 . 
     The memory  122  temporarily stores the inputted patient attribution information and examination attribution information, the image data and the image-associated information which are received from the image modality  11 , and the anatomical chart data received from the data center  20 . In the hard disk  123 , software (program) for allowing the CPU  121  to perform operation is recorded. As the recording medium for recording the program, not only the built-in hard disk  123 , but also an external hard disk, a flexible disk, an MO, an MT, a RAM, a CD-ROM, a DVD-ROM, or the like may be used. 
     Next, function blocks  121   a  to  121   e  formed by the CPU  121  and software (program) will be described. 
     The taking control unit  121   a  controls, via the interface  128 , the imaging device  40  to start an examination based on the patient attribution information and the examination attribution information which are stored in the memory  122 . 
     The image processing unit  121   b  performs necessary image processing on the image data received from the image reading device  50 , and generates display data for display on the display unit  63 . Further, the image processing unit  121   b  generates display data for display on the display unit  63  based on the anatomical chart data received from the data center  20 . The display data is supplied from the output unit  121   c  via the interface  127  to the display unit  63 , images are displayed on the display unit  63 , and the images are confirmed by an operator. Further, the image data subjected to the necessary image processing is stored in the memory  122 , and recorded in the hard disk  123  under the control of the hard disk control unit  124  according to the set conditions. 
     When desired image data is thus obtained, in order to store the medical data such as image data in the data center  20 , the transmission control unit  121   d  starts to access the data center  20  according to the instructions using the input unit  61  by the operator or set conditions. In the data center  20 , in order to prevent the leaks of personal information, the falsification of medical image data, or the like, an authentication is requested to access to the database server  24  ( FIG. 1 ), and access to the database server  24  is inhibited until it is allowed by the authentication. 
     When the transmission control unit  121   d  makes inquiries about access right to the authentication server  21  ( FIG. 1 ) of the data center  20  and the access right is authenticated in the authentication server  21 , the transmission control unit  121   d  transmits the medical data, which is stored in storage means such as the memory  122  or hard disk  123 , to the database server  24  and allows the server to record the data. 
     The information requesting unit  121   e  starts to access to the data center  20  in response to the instruction for downloading the anatomical chart inputted by the operator using the input unit  61 . In the same operation as described in the transmission control unit  121   d , when the access right is authenticated in the authentication server  21 , the information requesting unit  121   e  transmits an information request signal to the database server  24  so that the database server  24  may transmit anatomical chart data. Here, the information request signal includes image-associated information such as patient attribution information or examination attribution information, and information for identifying the transmission source of the information request signal such as medical facility serial number. 
     By the way, in the embodiment, the taking control unit  121   a , the image processing unit  121   b , the output unit  121   c , the transmission control unit  121   d , and the information requesting unit  121   e  are formed by a CPU and software, however, they may be formed by digital circuits or analog circuits. 
       FIG. 4  is a block diagram showing the constitution of the database server. The database server  24  includes an input unit  71  used for inputting various kinds of instructions, a display unit  72  for display for operation, a central processing unit (hereinafter, referred to as “CPU”)  73  to which the input unit  71  and the display unit  72  are connected via an interface  80 , a memory  74  for temporarily storing the medical data and the information request signal which are received from the client terminal  12  ( FIG. 1 ), a hard disk  75 , a hard disk control unit  76  for controlling the hard disk  75 , a network interface  77  for connection to a LAN, an interface  78  for controlling the medical database  25 , and an interface  79  for controlling the anatomical chart database  26 . These parts  71  to  79  are connected to one another via a bus line. 
     The memory  74  temporarily stores the medical data and the information request signal which are received from the client terminal  12  ( FIG. 1 ). In the hard disk  75 , software (program) for allowing the CPU  73  to perform operation is recorded. As the recording medium for recording the program, not only the built-in hard disk  75 , but also an external hard disk, a flexible disk, an MO, an MT, a RAM, a CD-ROM, a DVD-ROM, or the like may be used. 
     Next, function blocks  73   a  to  73   d  formed by the CPU  73  and software (program) will be described. 
     The reception control unit  73   a  receives the medical data transmitted from the client terminal ( FIG. 1 ), and the information request signal including the image-associated information. The data managing unit  73   b  manages the medical data received by the reception control unit  73   a  by recording the medical data in the recording medium of the medical database  25 , and manages the anatomical chart data by recording the anatomical chart data in the anatomical chart database  26 . 
     The retrieval control unit  73   c  reads out an anatomical chart filename from the anatomical chart retrieval table, which is recorded in the anatomical chart database  26 , using the imaging menu, the part to be examined, the image feature, or the like of the examination attribution information which is contained in the information request signal received by the reception control unit  73   a , as a retrieval keyword. Further, the retrieval control unit  73   c  retrieves anatomical chart data used for diagnosis recorded in the anatomical chart database  26 , based on the read anatomical chart filename. 
     The transmission control unit  73   d  transmits the retrieved anatomical chart data used for diagnosis to the client terminal  12  ( FIG. 1 ) of the transmission source based on the information for identifying the transmission source of the information request signal such as a medical facility serial number which is contained in the information request signal received by the reception control unit  73   a.    
     In the embodiment, the client terminal  12  ( FIG. 1 ) transmits the examination attribution information on diagnosis and examination of a patient to the database server  24 , and the database server  24  which receives the examination attribution information transmits the anatomical chart data used for diagnosis to the client terminal  12  ( FIG. 1 ). Thereby, the anatomical chart can be browsed by the simple operation of the client terminal  12  ( FIG. 1 ) while suppressing the space required for storing anatomical chart data in the clinic  10 . 
     By the way, the reception control unit  73   a , the data managing unit  73   b , the retrieval control unit  73   c , and the transmission control unit  73   d  are formed by the CPU and software (program), however, they may be formed by digital circuits or analog circuits. 
     Next, the operation of the diagnostic support system according to the embodiment will be described by referring to  FIGS. 1 to 6 .  FIGS. 5 and 6  are flowcharts showing the operation of the diagnostic support system in the embodiment. 
     At step S 1 , the operator inputs the patient attribution information and the examination attribution information using the input unit  61  of the client terminal  12 . By the way, these information may be inputted from another terminal such as a receipt computer. Then, at step S 2 , the client terminal  12  stores the patient attribution information and the examination attribution information, which are inputted via the interface  127  using the input unit  61 , in the memory  122 . 
     At step S 3 , the operator reads out the barcode attached to the cassette in which the recording sheet is stored, using the barcode reader  62 . At step S 4 , the client terminal  12  stores the barcode information generated by reading out the barcode, in association with the patient attribution information and the examination attribution information in the memory  122 . 
     At step S 5 , the operator inputs an instruction to start an examination using the input unit  61 . At step S 6 , the taking control unit  121   a  controls the imaging device  40  based on the patient attribution information and the examination attribution information in response to the instruction to start the examination. At step S 7 , the imaging device  40  takes a radiation image by applying radiation to an examinee under the control of the taking control unit  121   a , and records the radiation image onto the recording sheet. 
     At step S 8 , the image reading device  50  generates image data by reading the radiation image recorded on the recording sheet  1 , and transmits the generated image data with the barcode information to the client terminal  12 . 
     At step S 9 , the client terminal  12  stores the image data and the barcode information which are received from the image reading device  50 , in the memory  122 . Here, the client terminal  12  matches the barcode information received from the medical image reading device  50  with the barcode information generated by the barcode reader  62 , and thereby, associates the image data with the patient attribution information and the examination attribution information. 
     At step S 10 , the image processing unit  121   b  performs image processing on the image data stored in the memory  122 . At step S 11 , the image processing unit  121   b  stores the image data representing the medical images, and the patient attribution information and the examination attribution information which are associated with the medical images, in storage means such as the hard disk  123 . 
     At step S 12 , the transmission control unit  121   d  makes inquiries about access right to the authentication server  21  of the data center  20 . When the access right is authenticated by the authentication server  21 , at step S 13 , the transmission control unit  121   d  transmits the stored medical data such as image data from the client terminal  12  to the database server  24  of the data center  20 . 
     At step S 14 , the reception control unit  73   a  of the database server  24  receives the medical data. At step S 15 , the data managing unit  73   b  records the medical data received by the reception control unit  73   a , in the recording medium of the medical data base  25 . Thereby, the medical image data is stored in the data center  20 . 
     Referring to  FIG. 6 , at step S 16 , radiation images are displayed on the display unit  63  of the client terminal  12  based on the image data subjected to image processing at step S 10 . 
     Then, at step S 17 , a doctor as the operator performs consultation while interpreting the radiation images being displayed on the display unit  63 , and inputs an instruction to download an anatomical chart using the input unit  61 . At step S 18 , the information requesting unit  121   e  makes inquiries about access right to the authentication server  21  of the data center  20  in response to the instruction to download the anatomical chart. 
     When the access right is authenticated by the authentication server  21 , at step S 19 , the information requesting unit  121   e  transmits an information request signal from the client terminal  12  to the database server  24  of the data center  20  so that the data center  20  may transmit anatomical chart data. The information request signal contains information for identifying the transmission source such as the medical facility serial number with the imaging menu, the part to be examined, the image feature, etc. 
     Then, at step S 20 , the reception control unit  73   a  of the database server  24  receives the information request signal. At step S 21 , the retrieval control unit  73   c  reads out the corresponding anatomical chart filename and alpha channel information from the anatomical chart retrieval table recorded in the anatomical chart database  26 , using the imaging menu, the part to be examined, the image feature, or the like of the examination attribution information, which are contained in the information request signal received by the reception control unit  73   a , as a retrieval keyword. At step S 22 , the retrieval control unit  73   c  retrieves anatomical chart data used for diagnosis from the anatomical chart database  26  based on the read anatomical chart filename. 
       FIG. 7  shows an example of the anatomical chart retrieval table recorded in the anatomical chart database. As shown in  FIG. 7 , in the anatomical chart retrieval table, the imaging menu, the anatomical chart filenames of data files in which anatomical chart data are stored, and the alpha channel information are stored in association with one another. For example, imaging menu “cephalic part front”, anatomical chart filename “AC001”, and alpha channel information “0.4” are associated. Further, imaging menu “cephalic part side”, anatomical chart filename “AC002”, and alpha channel information “0.4” are associated. Similarly, imaging menu “thoracic part front”, anatomical chart filename “AC005”, and alpha channel information “0.4” are associated 
     Therefore, when the reception control unit  73   a  receives an information request signal containing “thoracic part front” as an imaging menu item, the retrieval control unit  73   c  reads out “AC005” as the corresponding anatomical chart filename from the anatomical chart retrieval table based on the retrieval keyword of “thoracic part front”, and reads out “0.4” as the corresponding alpha channel information. Further, the retrieval control unit  73   c  retrieves anatomical chart data of anatomical chart filename “AC005” from the anatomical chart database  26  based on the read anatomical chart filename “AC005”. 
     Similarly, in the anatomical chart retrieval table, the parts to be examined, the image features, or the like may be associated with the anatomical chart filenames, and the anatomical chart filename may be read out based on the part to be examined, the image feature, or the like contained in the examination attribution information for retrieval of anatomical chart data. 
     Referring to  FIG. 6  again, at step S 23 , the transmission control unit  73   d  returns the anatomical chart data and the alpha channel information, which are used for diagnosis, to the client terminal  12  of transmission source based on the information for identifying the transmission source of the information request signal such as a medical facility serial number contained in the information request signal received by the reception control unit  73   a.    
     At step S 24 , the client terminal  12  stores the received anatomical chart data and alpha channel information in the memory  122 . At step S 25 , the image processing unit  121   b  allows the display unit  63  to display an anatomical chart based on the anatomical chart data stored in the memory  122 . The image processing unit  121   b  displays the anatomical chart and the radiation image side by side, or displays the anatomical chart superimposed on the radiation image, based on the display form command inputted by the operator using the input unit  61 . 
       FIG. 8  shows a parallel display screen in which a radiation image and an anatomical chart are displayed side by side. On the parallel display screen  90 , a menu  91  including a radiation image  92 , an anatomical chart  93 , a display changeover button  94  and an exit button  95  is displayed. 
     Thus, by displaying the radiation image and the anatomical chart, the doctor as the operator can use the anatomical chart as an object of comparison when the taken radiation image is unclear, or use when explaining the taken radiation image to the patient. The operator can instruct to switchover between the parallel display screen in which the radiation image and the anatomical chart are displayed side by side, and the superimposition screen in which the radiation image and the anatomical chart are superimposed and displayed. 
     When the radiation image and the anatomical chart are superimposed and displayed, the image processing unit  121   b  detects the overlapping of the radiation image and the anatomical chart, and obtains pixel values in the respective pixels in the overlapping part based on the alpha channel information associated with the anatomical chart data as the following equation. 
               (     pixel   ⁢           ⁢   value   ⁢           ⁢   of   ⁢           ⁢   superimposed   ⁢           ⁢   image   ⁢           ⁢   data     )     =         (     1   -   α     )     ×     (     pixel   ⁢           ⁢   value   ⁢           ⁢   of   ⁢           ⁢   examination   ⁢           ⁢   image   ⁢           ⁢   data     )       +     α   ×     (     pixel   ⁢           ⁢   value   ⁢           ⁢   of   ⁢           ⁢   anatomical   ⁢           ⁢   chart   ⁢           ⁢   data     )               
Here, α is a value equal to or more than “0” and equal to or less than “1” representing the degree of transparency of the anatomical chart. The value of the alpha channel of the displayed superimposed image can be changed using the input unit  61 .
 
     In the above embodiment, the information requesting unit  121   e  transmits the examination attribution information by including the information in the information request signal, however, the client terminal  12  may collect data, which represents a name of sick and is obtained by this diagnosis and contained in data of electronic medical chart or the like and recorded in another terminal, in response to the instruction to download the anatomical chart, the information requesting unit  121   e  may transmit the data representing the name of sick by including the data in the information request signal, and the database server  24  may read out the anatomical chart filename based on the data representing the name of sick and retrieve anatomical chart data. 
     Further, the client terminal  12  may collect the data, which represents the name of sick and is obtained by past diagnosis and contained in data of an electronic medical chart or the like and recorded in another terminal, in response to the reception completion of a patient who has been diagnosed in the past, the information requesting unit  121   e  may transmit the data representing the name of sick by including the data in the information request signal, and the database server  24  may read out the anatomical chart filename based on the data representing the name of sick and retrieve the anatomical chart data. 
     Or, the transmission control unit  73   d  of the database server  24  may transmit the read anatomical chart filename together with the retrieved anatomical chart data or the like to the client terminal  12 , the client terminal  12  has stored information such as anatomical chart filenames as history information of anatomical charts used in the past for the respective patients, the information requesting unit  121   e  of the client terminal  12 , in response to the reception completion of a patient who has been diagnosed in the past, transmits an anatomical chart filename most recently or most frequently used in the history information of anatomical charts used in the past for the patient by including the filename in the information request signal, and the database server  24  may retrieve anatomical chart data based on the anatomical chart filename. 
     Thus, in the case where the anatomical chart data is downloaded based on the name of sick obtained in the past diagnosis and the history of anatomical charts used in the past, when a patient who has been diagnosed in the past visits the hospital again and the reception is completed, the anatomical chart data can be downloaded prior to the examination, and thereby, the anatomical chart can be displayed immediately after the examination.