JP2010017215A - X-ray ct apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray CT apparatus capable of intuitively compiling and specifying conditions for reconstructing an image based on X-ray projection data acquired by radiography with time change. <P>SOLUTION: A time chart creation section 61 creates a time chart indicating time changes in radiographing conditions. A display control section 32 displays the time chart, the radiographing conditions and reconstruction conditions on a display section 71. An operator specifies new reconstruction conditions on the time chart displayed on the display section 71 and a screen displaying the reconstruction conditions using an operation section 72. A reconstruction process section 23 generates image data by reconstructing X-ray projection data according to the specified new reconstruction conditions. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an X-ray CT apparatus having a function of supporting specification of conditions relating to image reconstruction.

  The X-ray CT apparatus rotates an X-ray tube and an X-ray detector, which are arranged opposite to each other with a subject interposed therebetween, to irradiate the subject with X-rays by rotating the X-ray tube around the subject. The transmitted amount (transmitted X-ray dose) is detected by an X-ray detector. The detected data is collected as X-ray projection data by a data collection device, and the collected X-ray projection data is reconstructed using a computer to generate image data of the subject.

  Conventionally, a routine inspection flow is programmed in advance, and the routine is sequentially executed by reading the program in one operation.

  Further, in the X-ray CT apparatus according to the conventional technique, a scan sequence in which a plurality of scanning operations controlled under a plurality of imaging conditions (scanning conditions) is ordered is created, and a time chart showing a time change of the scan sequence (Patent Document 1). For example, a time chart representing a scan sequence as a time change of a tube current or other dose index applied to an X-ray tube is displayed. An operator refers to a scan sequence represented by a change in time such as a tube current and performs imaging by designating a desired scan sequence.

  By the way, with the increase in the number of rows of X-ray detectors, a certain range having a width in the body axis direction of the subject is continuously imaged (dynamic scan). For example, in a perfusion examination, a three-dimensional region is continuously imaged by injecting a contrast medium into a subject and performing a dynamic scan. When reconstructing image data based on X-ray projection data acquired by such imaging, a list of X-ray projection data is displayed on the screen of the display device. When the operator selects desired X-ray projection data from the list, the examination information including the imaging conditions for acquiring the X-ray projection data and the initially set reconstruction conditions is displayed as character information on the display device. It was displayed on the screen. The operator refers to the character information and changes or inputs the reconstruction condition to designate a desired reconstruction condition.

  Here, a display example of inspection information according to the conventional technique is shown in FIGS. FIG. 16 and FIG. 17 are screen views showing examples of display of inspection information according to the prior art. For example, as shown in FIG. 16, examination information 600 including imaging conditions (scanning conditions) such as imaging slice thickness and bed speed and reconstruction conditions such as image slice thickness and reconstruction interval is displayed as character information on the display device. It was displayed on the screen. As another display format, as shown in FIG. 17, inspection information 700 such as imaging slice thickness (Slice Thickness) and imaging time (Time) is displayed as character information on the screen of the display device. The operator refers to the character information displayed on the screen and changes or inputs the reconstruction condition.

JP 2008-48856 A

  However, according to the prior art, since the imaging conditions and reconstruction conditions are displayed as character information, when performing image reconstruction, it is possible to intuitively select X-ray projection data and set reconstruction conditions. I could not. When continuous shooting is performed as in dynamic scanning or the like, it is necessary to determine a time zone to be reconstructed. However, in the related art, information on the shooting time has not been sufficiently provided. For example, only time information of a part of the entire imaging time is displayed, and the imaging time over the entire examination is not displayed, so it is difficult to grasp the entire examination. In addition, when the inspection was performed by combining multiple shootings, the time of each shooting and the order of the shootings were displayed as character information, so it was intuitive to know at what timing each shooting was performed during the entire test. It was difficult to grasp.

  Further, the X-ray CT apparatus has a function of setting the contents of the routine inspection in advance in the X-ray CT apparatus and reading and executing the contents at the time of inspection. However, when imaging is performed by injecting a contrast medium into a subject, the method of staining the contrast medium varies from person to person. Therefore, for each subject, the contents of the routine examination are edited and set in the X-ray CT apparatus. It is necessary to keep. For example, it is necessary to set the X-ray CT apparatus by changing the imaging timing for each subject. However, since the imaging conditions and reconstruction conditions included in the contents of the routine inspection are displayed using only character information, the contents of the routine inspection cannot be intuitively grasped and edited. For this reason, it has been difficult to set the contents of the routine examination tailored to each subject. Therefore, there is a demand for improvement of auxiliary functions for editing routine inspection contents.

  The present invention solves the above problem, and it is possible to intuitively edit and specify conditions for reconstructing an image based on X-ray projection data acquired by time-dependent imaging. An object is to provide a possible X-ray CT apparatus.

  According to the first aspect of the present invention, an X-ray source, an X-ray detector disposed opposite to the X-ray source across the subject, and an X-ray source from the X-ray source according to imaging conditions that change with time are exposed. A scan control unit that performs imaging by shooting, and a reconstruction processing unit that generates image data by performing reconstruction processing on the X-ray projection data acquired by the imaging according to a predetermined reconstruction condition; , A time chart creating means for creating a time chart representing a time change of examination information including the imaging conditions and the reconstruction conditions, and a display for displaying the time chart, the imaging conditions, and the reconstruction conditions on a display means Control means; designation means for designating a new reconstruction condition on the time chart displayed on the display means and on the screen displaying the reconstruction condition; and the reconstruction processing Means is an X-ray CT apparatus characterized by generating a new image data by reconstruction processing performed in accordance with said specified the new reconstruction conditions.

  According to the present invention, a time chart showing the time change of inspection information including imaging conditions and reconstruction conditions is created, and the time chart is displayed to visually grasp the entire inspection actually performed. It becomes possible. Then, by specifying the reconstruction condition on the time chart, it is possible to visually grasp the reconstruction condition and to intuitively specify the reconstruction condition.

  An X-ray CT apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing an X-ray CT apparatus according to an embodiment of the present invention.

  The X-ray CT apparatus according to this embodiment includes a gantry device 10, a console unit 20, and a couch device 80. The gantry 10 includes a rotating gantry (gantry) in which an X-ray tube and an X-ray detector are stored, and collects X-ray projection data related to the subject. The X-ray projection data is output to the console unit 20 and used for processing such as reconstruction processing. The couch device 80 includes a couch 81 for placing a subject.

  The gantry device 10 is provided with an X-ray tube 12 and an X-ray detector 13 paired with the X-ray tube 12. The X-ray detector 13 includes a plurality of detection elements arranged in two directions orthogonal to each other (slice direction (body axis direction) and channel direction (circumferential direction)), thereby two-dimensional X-ray detection. Make up the vessel. For example, the X-ray detector 13 is a multi-row X-ray detector having 64 rows or 256 rows. The high voltage generator 11 supplies a high voltage for irradiating X-rays to the X-ray tube 12 in accordance with a control signal from the scan controller 24.

  The data collection unit 14 includes data collection elements arranged in the same manner as the detection elements of the X-ray detector 13. The data collection unit 14 collects X-rays (detection signals) detected by the X-ray detector 13 in correspondence with the data collection control signal output from the scan control unit 24. This collected data is X-ray projection data. The data collection unit 14 converts the current signal of each channel of the X-ray detector 13 into a voltage, amplifies it, and converts it into a digital signal. The X-ray projection data is sent to the preprocessing unit 21 of the console unit 20 via a data transmission device (not shown).

  The X-ray tube 12, the X-ray collimator (not shown), the X-ray detector 13, and the data collection unit 14 are fixed to a rotating gantry (not shown). The gantry driving unit 15 rotates a rotating gantry (not shown) based on the gantry control signal output from the scan control unit 24. As a result, the rotary mount is rotated about the rotation center.

  The X-ray beam irradiated from the X-ray tube 12 is irradiated to the subject through an X-ray collimator provided with a slit (opening) having a predetermined width. The X-ray beam transmitted through the subject is detected by the X-ray detector 13, and the detection signal is amplified by the data acquisition unit 14, converted into a digital signal, and collected as X-ray projection data.

  The console unit 20 includes a preprocessing unit 21, a data storage unit 22, a reconstruction processing unit 23, a scan control unit 24, a control unit 30, a management unit 40, an imaging protocol storage unit 50, a processing unit 60, and a user interface (UI). 70.

  The preprocessing unit 21 performs processing such as sensitivity correction and X-ray intensity correction on the X-ray projection data collected by the data collection unit 14. The X-ray projection data that has been subjected to processing such as sensitivity correction in the preprocessing unit 21 is stored in the data storage unit 22.

  The reconstruction processing unit 23 reads X-ray projection data from the data storage unit 22 and backprojects the X-ray projection data to reconstruct tomographic image data. The reconstruction processing unit 23 outputs the generated tomographic image data to the display control unit 32. The display control unit 32 causes the display unit 71 to display a tomographic image based on the tomographic image data. Further, the reconstruction processing unit 23 outputs the generated tomographic image data to the data storage unit 22. The data storage unit 22 stores tomographic image data.

  The scan control unit 24 supplies a rotation control signal to the gantry driving unit 15 in order to stably rotate the rotating gantry at a constant speed according to the imaging conditions. Further, the scan control unit 24 outputs an X-ray generation control signal for controlling X-ray generation to the high voltage generation unit 11 according to the imaging conditions, and sends a detection control signal indicating the detection timing of the X-rays to the data collection unit 14. Output.

  The couch device 80 includes a couch 81 and a couch drive unit 82. The bed 81 includes a bed top for placing a subject and a bed base for supporting the bed top. The couch top can be moved by the couch driving unit 82 in the body axis direction (slice direction) of the subject. The bed base can be moved up and down by the bed driving unit 82.

  Here, a scanning operation unit controlled under a single imaging condition (scanning condition) is referred to as a scanning element. One inspection is composed of a plurality of scanning elements. A plurality of scan elements constituting one inspection are ordered. A plurality of scanning conditions respectively correspond to the plurality of scan elements, but the plurality of shooting conditions are not necessarily different from each other, and the same shooting conditions may be included.

  The imaging conditions include a scan mode for distinguishing the type of imaging, tube voltage supplied to the X-ray tube 12, tube current supplied to the X-ray tube 12, bed speed, imaging field diameter (S-FOV), Diameter of constituent field of view (D-FOV), imaging slice thickness, helical pitch, number of slices, start time indicating elapsed time from the start of imaging, waiting time indicating time interval between adjacent scan elements, X in the scan element Information such as a pause time indicating a line generation interval and part information indicating a part to be imaged is included. As an example, the scan mode includes modes such as scan imaging, dynamic scan, and helical scan.

  The reconstruction condition includes information such as the image slice thickness, the reconstruction interval, the start position of the reconstruction range, and the end position of the reconstruction range. The reconstruction processing unit 23 reconstructs image data from the X-ray projection data according to the reconstruction condition.

(Shooting protocol storage unit 50)
The imaging protocol storage unit 50 stores imaging protocols for executing various examinations. The imaging protocol for one examination includes a plurality of imaging conditions for executing a plurality of scan elements constituting one examination, and a reconstruction condition.

(Control unit 30)
The control unit 30 includes an editing unit 31 and a display control unit 32. The control unit 30 reads the shooting protocol from the shooting protocol storage unit 50 and outputs a plurality of shooting conditions corresponding to the plurality of scan elements to the scan control unit 24. For example, the display control unit 32 creates a list of a plurality of imaging protocols and causes the display unit 71 to display the list. The operator uses the operation unit 72 to specify a desired photographing protocol from the list. The control unit 30 receives the designation, reads the designated imaging protocol from the imaging protocol storage unit 50, and outputs the imaging conditions to the scan control unit 24. The scan control unit 24 performs imaging by controlling each unit in accordance with each imaging condition corresponding to each scan element. The X-ray projection data acquired by this imaging is stored in the data storage unit 22.

  Further, the control unit 30 outputs the reconfiguration condition to the reconfiguration processing unit 23 and gives an instruction for reconfiguration to the reconfiguration processing unit 23. The reconstruction processing unit 23 reconstructs image data by performing back projection processing on the X-ray projection data in accordance with the reconstruction condition output from the control unit 30. Further, the control unit 30 outputs inspection information including the imaging conditions and the reconstruction conditions to the management unit 40.

  In this embodiment, a case where dynamic scanning is performed will be described as an example. That is, X-ray projection data with different times of acquisition is acquired by continuously imaging a certain range having a width in the body axis direction of the subject. As a result, the reconstruction processing unit 23 generates a plurality of tomographic image data with different taken times. The plurality of tomographic image data that have been taken at different times are stored in the data storage unit 22.

(Management unit 40)
The management unit 40 manages information such as X-ray projection data, inspection information, and inspection history. For example, the management unit 40 adds information including imaging conditions and reconstruction conditions to the X-ray projection data as past examination information and stores the information in the data storage unit 22. Furthermore, the management unit 40 adds the patient ID, which is identification information for identifying the patient, and the examination ID, which is identification information for identifying the examination, to the X-ray projection data and stores them in the data storage unit 22. . As described above, the management unit 40 causes the patient ID, the examination ID, and the examination information to be attached to the X-ray projection data and stored in the data storage unit 22. Thereby, X-ray projection data can be read from the data storage unit 22 by the patient ID and the examination ID.

  The control unit 30 creates a list of patient IDs indicating registered patients and a list of test IDs indicating past examinations. The display control unit 32 causes the display unit 71 to display a list of patient IDs. When the operator designates the patient ID of the patient to be examined from the list of patient IDs using the operation unit 72, the display control unit 32 displays the list of examination IDs of the designated patient as the display unit 71. To display. The operator uses the operation unit 72 to specify a desired examination ID from the examination ID list. The control unit 30 outputs the designated patient ID and examination ID to the management unit 40. The management unit 40 reads the past examination information accompanied by the designated patient ID and examination ID from the data storage unit 22 and outputs them to the control unit 30 and the processing unit 60. As a result, past imaging conditions and reconstruction conditions are output to the control unit 30 and the processing unit 60.

(Processing unit 60)
The processing unit 60 includes a time chart creation unit 61, an imaging condition screen creation unit 62, a reconstruction condition screen creation unit 63, and an analysis unit 64. The processing unit 60 creates a screen representing the shooting conditions and the reconstruction conditions.

(Time chart creation unit 61)
The time chart creation unit 61 receives the examination information with the designated patient ID and examination ID attached from the management unit 40, and creates a time chart representing a time change of past examination information. For example, the time chart creation unit 61 creates a time chart that represents a temporal change in tube current included in the imaging conditions. Then, the time chart creation unit 61 outputs data indicating the time chart to the display control unit 32. The display control unit 32 receives data indicating the time chart from the time chart creation unit 61 and causes the display unit 71 to display the time chart. For example, the display control unit 32 causes the display unit 71 to display a time chart representing the time change of the tube current.

  Here, FIG. 2 shows an example of a time chart. FIG. 2 is a diagram of a screen showing a time chart showing a time change of the tube current. As illustrated in FIG. 2, the display control unit 32 causes the display unit 71 to display a time chart 100 that represents a time change of the scan elements 110 to 140 included in one examination. In the time chart 100, the horizontal axis is time, and the vertical axis is tube current (mA). On the time chart 100, the scan elements 110 to 140 are represented by frame-like figures having a width corresponding to the length of the photographing time and a height corresponding to the value of each tube current. Note that the tube current (mA) may be displayed in place of another index representing the dose. Other indexes include an index indicating the total tube current value of the scan time, an index (mAs) calculated from the tube current set in the examination plan and the actual exposure time, and the exposure dose per unit slice thickness (CTDIw) ), Or a total exposure dose (DLP) or the like may be used.

(Shooting condition screen creation unit 62)
The imaging condition screen creation unit 62 receives examination information with the designated patient ID and examination ID from the management unit 40, and creates an imaging condition screen that represents past imaging conditions in a table format (table format). . Specifically, the imaging condition screen creation unit 62 creates an imaging condition screen that represents each scan element included in one examination in a table format (table format). Then, the shooting condition screen creation unit 62 outputs data indicating the shooting condition screen to the display control unit 32. The display control unit 32 receives data indicating the imaging condition screen from the imaging condition screen creation unit 62 and causes the display unit 71 to display an imaging condition screen in which scan elements are arranged in a table format.

  Here, an example of the photographing condition screen is shown in FIG. FIG. 3 is a diagram showing a shooting condition screen showing the shooting conditions in a tabular format. As illustrated in FIG. 3, the display control unit 32 causes the display unit 71 to display the imaging condition 200 in which a plurality of scan elements 201 to 205 are arranged in a table format (table format). As an example, each table includes a scan element number, a start time (Start Time) corresponding to the elapsed time of each scan element after the trigger operation for starting imaging, and the end of the immediately preceding scan element. Waiting time (Wait) as an interval until start, shooting start position (Start Pos.) Of each scan element, shooting end position (End Pos.) Of each scan element, and a scan mode (Scan) for distinguishing the type of shooting Items such as “Mode” are included. Each item is represented by a numerical value or a symbol.

  The display control unit 32 also includes a tube voltage (kV), a tube current (mA), an imaging time (Rot.Time), a reconstruction field diameter (D-FOV), an execution mAs (Eff.mAs), and an imaging total. Conditions such as time (Total Scan Time) are displayed on the display unit 71 as the imaging conditions 200. For example, when the operator designates any one of the scan elements 201 to 205 using the operation unit 72, the display control unit 32 sets conditions such as tube voltage (kV) and tube current (mA) in the designated scan element. It is displayed on the display unit 71 in another window. In the example shown in FIG. 3, when the operator designates the scan element 203 using the operation unit 72, the display control unit 32 displays the conditions such as the tube voltage and the tube current in the designated scan element 203 in another window. Display on the unit 71.

(Reconfiguration condition screen creation unit 63)
The reconstruction condition screen creation unit 63 receives the examination information attached with the designated patient ID and examination ID from the management unit 40, and creates a reconstruction condition screen representing past reconstruction conditions. Specifically, the reconstruction condition screen creation unit 63 creates a reconstruction condition screen that represents information such as the image slice thickness, the reconstruction interval, the start position of the reconstruction range, and the end position of the reconstruction range. Then, the reconstruction condition screen creation unit 63 outputs data indicating the reconstruction condition screen to the display control unit 32. The display control unit 32 receives data indicating the reconstruction condition screen from the reconstruction condition screen creation unit 63 and causes the display unit 71 to display the reconstruction condition screen on which the reconstruction condition is expressed.

  An example of the reconstruction condition screen is shown in FIG. FIG. 4 is a diagram showing a reconstruction condition screen showing the reconstruction condition. For example, as illustrated in FIG. 4, the display control unit 32 includes an image slice thickness (Slice Thickness), a reconstruction interval (Slice Interval), a reconstruction range start position (Start Position), and a reconstruction range end position ( A reconstruction condition 310 such as “End Position” is displayed on the display unit 71. The display control unit 32 displays an input field for each item of the reconstruction condition 310 on the display unit 71, and the operator can input a numerical value to each item using the operation unit 72. Thereby, reconstruction conditions such as an image slice thickness and a reconstruction interval can be changed. The display control unit 32 may cause the display unit 71 to display the imaging condition 300 in which a plurality of scan elements 301 to 305 are arranged in a table format (table format) simultaneously with the reconstruction condition 310.

  In this embodiment, the display control unit 32 causes the display unit 71 to switch between a time chart, an imaging condition screen, and a reconstruction condition screen. That is, the display control unit 32 switches the time chart 100 illustrated in FIG. 2, the imaging condition 200 illustrated in FIG. 3, and the reconstruction condition 310 illustrated in FIG. For example, the display control unit 32 causes the display unit 71 to display a button 101 for switching the display format. When the operator operates the switching button 101 using the operation unit 72, the display control unit 32 switches between the time chart and the photographing condition screen according to the operation and causes the display unit 71 to display the time chart. Specifically, when the operator designates the time sequence (Time Sequence) of the button 101 using the operation unit 72, the display control unit 32 causes the display unit 71 to display the time chart 100 shown in FIG. On the other hand, when the operator designates the scan sequence (Scan Sequence) of the button 101 using the operation unit 72, the display control unit 32 displays the photographing condition 200 shown in FIG. 3 on the display unit 71. Further, when the operator gives an instruction to display the reconstruction condition using the operation unit 72, the display control unit 32 causes the display unit 71 to display the reconstruction condition 310 shown in FIG.

  As described above, it is possible to visually grasp the entire inspection actually performed by displaying the temporal change of the past inspection information. For example, as shown in FIG. 2, the entire examination can be visually grasped by displaying a time chart representing the time change of the imaging conditions. In addition, it is possible to visually grasp the length of time of actual photographing and the timing at which each scan element is executed. Thus, the visibility of past inspection information can be improved.

(Specifying reconfiguration conditions)
Then, the operator uses the operation unit 72 to specify the reconstruction condition with reference to the information shown on the screens shown in FIGS. For example, the operator uses the operation unit 72 to designate a time zone to be reconfigured on a time chart representing a time change of the imaging condition. By designating the time zone to be reconfigured, the scan element to be reconfigured is designated. This designation method will be described with reference to FIG. FIG. 5 is a diagram of a screen showing a time chart showing a time change of the tube current. As shown in FIG. 5, the display control unit 32 causes the display unit 71 to display a time chart 100 that represents a time change of the scan elements 110 to 150 included in one examination. The display control unit 32 also includes data indicating the first marker for designating the start time of the time zone to be reconfigured and the second time for designating the end time of the time zone to be reconstructed. Data indicating a marker is generated. Then, the display control unit 32 causes the display unit 71 to display the first marker 102 and the second marker 103 in the area where the time chart 100 is represented. Using the operation unit 72, the operator designates the start time of the time zone to be reconfigured by the first marker 102 on the time chart 100 and the time zone to be reconfigured by the second marker 103. Specify the end time. The time zone specified by the first marker 102 and the second marker 103 corresponds to the time zone to be reconfigured. That is, the scan element included in the time zone specified by the first marker 102 and the second marker 103 corresponds to the scan element to be reconfigured.

  For example, as illustrated in FIG. 5, the operator uses the operation unit 72 to specify a time zone in which the scan elements 110 to 140 are included, using the first marker 102 and the second marker 103. By this designation, the scan elements 110 to 140 are designated as scan elements to be reconfigured. That is, the X-ray projection data collected by each of the scan elements 110 to 140 is designated as the target data for the reconstruction process.

  Moreover, you may designate the time interval which performs a reconstruction between start time and end time. For example, as shown in FIG. 5, between the first marker 102 and the second marker 103, a time interval for performing reconstruction is designated by a marker indicated by a broken line. The operator also specifies conditions such as the image slice thickness, the slice interval, and the range for reconstruction. For example, on the screen shown in FIG. 4, the operator uses the operation unit 72 to re-create image slice thickness (Slice Thickness), slice interval (Slice Interval), start position (Start Position), and end position (End Position). Enter the configuration conditions.

  As described above, when the reconstruction conditions including the time zone (start time and end time), the image slice thickness, the slice interval, the start position, and the end position to be subjected to the reconstruction process are designated by the operator, The reconfiguration condition is output from the user interface (UI) 70 to the control unit 30. The control unit 30 outputs the reconstruction condition to the reconstruction processing unit 23 and requests the reconstruction processing unit 23 to perform the reconstruction process. For example, as illustrated in FIG. 4, the display control unit 32 displays a button 320 for requesting the reconstruction process on the display unit 71, and when the operator operates the button 320 using the operation unit 72, the reconstruction process is performed. Is output from the user interface (UI) 70 to the control unit 30. Upon receiving a request from the user interface (UI) 70, the control unit 30 requests the reconfiguration processing unit 23 to perform reconfiguration processing. The reconstruction processing unit 23 reads the X-ray projection data collected in the time zone to be subjected to the reconstruction process included in the reconstruction condition from the data storage unit 22, and the image slice thickness and the slice interval included in the reconstruction condition The tomographic image data is generated by performing reconstruction processing according to the conditions such as. That is, the reconstruction processing unit 23 reads the X-ray projection data collected by the scan element that is the target of the reconstruction process from the data storage unit 22, and performs the reconstruction process according to the reconstruction condition. Then, the reconstruction processing unit 23 outputs the reconstructed tomographic image data to the display control unit 32. The display control unit 32 receives tomographic image data from the reconstruction processing unit 23 and causes the display unit 71 to display a tomographic image based on the tomographic image data. In the example shown in FIG. 5, since the time zone in which the scan elements 110 to 140 are included is designated, the reconstruction processing unit 23 stores the X-ray projection data collected in the scan elements 110 to 140 from the data storage unit 22. The tomogram data is generated by performing the reconstruction process on the read X-ray projection data.

(Tomographic image and time chart)
Here, a display example of a tomographic image is shown in FIG. FIG. 6 is a screen diagram showing a tomographic image and a time chart. As illustrated in FIG. 6, the display control unit 32 causes the display unit 71 to display a list 400 of a plurality of tomographic images generated by the reconstruction process. The plurality of tomographic images are images generated based on the reconstruction conditions described above. That is, the plurality of tomographic images are images generated based on the X-ray projection data collected in the time zone to be reconstructed. Further, the display control unit 32 causes the display unit 71 to display a time chart representing a temporal change in past examination information. As an example, the display control unit 32 causes the display unit 71 to display the time chart 100 including the scan elements 110 to 140 representing the time change of the tube current. Then, based on the information indicating the time zone (start time and end time) that is the target of the reconstruction process, the display control unit 32 sets the scan element included in the time zone as another scan element in the time chart 100. It can be identified and displayed on the display unit 71. For example, when the tomographic image data is reconstructed based on the X-ray projection data collected by the scan element 130, the display control unit 32 displays the scan element 130 on the display unit 71 such that the scan element 130 can be distinguished from other scan elements. . As an example, the display control unit 32 causes the display unit 71 to display the scan element 130 in a specific color set in advance.

  As described above, the time chart 100 representing the time change of the imaging condition is displayed, and the time zone that is the target of the reconstruction process can be specified on the time chart 100, so that it becomes the object of the reconstruction process. It is possible to visually grasp a desired time zone and intuitively specify the time zone. In other words, it is possible to visually grasp a desired image to be reconstructed and to intuitively specify the image. Further, the reconstructed image is displayed on the entire inspection by identifying and displaying the scan element 130 to be reconstructed on the time chart 100 representing the time change of the imaging condition. It is possible to visually grasp at which time zone the image was acquired. In other words, it is possible to visually grasp which reconstructed image is an image acquired by which scan element of the entire examination.

  Note that on the screen on which the tomographic image and the time chart 100 are displayed, the operator may further specify a time zone to be subjected to the reconstruction process using the operation unit 72. By this designation, the scan element to be reconfigured is designated. In other words, X-ray projection data to be reconstructed is specified by the specification. When the operator gives an instruction for reconstruction processing using the operation unit 72, the reconstruction processing unit 23 reads X-ray projection data collected in the newly designated time zone from the data storage unit 22, By performing reconstruction processing on the read X-ray projection data, new tomographic image data is generated. Then, the display control unit 32 causes the display unit 71 to display a tomographic image based on the newly generated tomographic image data.

(Time chart and scanogram)
Further, before performing imaging such as dynamic scanning or helical scanning, positioning scanning for determining the imaging range is performed. In this positioning scan, the bed on which the subject is on is moved in the body axis direction of the subject and the entire moving range is imaged. By this positioning scan, scanogram image data representing the entire movement range is acquired and stored in the data storage unit 22 in advance. In this embodiment, the scanogram image is displayed on the display unit 71 together with the time chart. An example of this display is shown in FIG. FIG. 7 is a diagram of a screen showing a scanogram image and a time chart. The display control unit 32 causes the display unit 71 to display the time chart 100 including the scan elements 110 to 140. Further, the display control unit 32 causes the display unit 71 to display a scanogram image 410 representing the upper surface of the subject and a scanogram image 420 representing the side surface of the subject together with the time chart 100. Image data representing the scanogram image 410 and image data representing the scanogram image 420 are image data acquired in advance by positioning scanning, and are stored in the data storage unit 22. The display control unit 32 reads image data representing a scanogram image from the data storage unit 22 via the management unit 40 and causes the display unit 71 to display the scanogram images 410 and 420.

  Furthermore, the display control unit 32 makes the display unit 130 distinguishable from other scan elements in the time chart 100 based on the information indicating the time zone that is the target of the reconstruction process. 71 is displayed. In addition, the display control unit 32 displays a marker indicating the range to be reconstructed based on information indicating the range to be reconstructed (information indicating the start position and end position of the reconfiguration process). Generate data to show. Then, the display control unit 32 causes the display unit 71 to display a marker indicating the range to be reconstructed on the scanogram image 410 and the scanogram image 420. As an example, the display control unit 32 generates a frame-shaped marker 411 and a marker 421 that indicate a range to be reconstructed. Then, the display control unit 32 causes the display unit 71 to display the frame-shaped marker 411 so as to overlap the range to be reconstructed in the scanogram image 410. Similarly, the display control unit 32 causes the display unit 71 to display a frame-shaped marker 421 in a range to be reconstructed in the scanogram image 420. The scanogram image corresponds to an example of the “positioning image” of the present invention.

  As described above, in the scanogram image, the range to be reconstructed is surrounded by the marker. Also, in the time chart, the time zone that is the target of the reconstruction process is identifiable. In this way, by displaying the position to be reconstructed and the time zone to be reconstructed, the reconstructed image is acquired at which time zone and at which position of the entire examination. It is possible to visually grasp whether the image has been made.

  Note that on the screen on which the scanogram image and the time chart 100 are displayed, the operator may further specify a range and a time zone to be reconstructed using the operation unit 72. That is, the time zone that is the target of the reconstruction process is specified on the time chart 100, and the range (position) that is the target of the reconstruction process is specified on the scanogram images 410 and 420. When the operator gives an instruction for reconstruction processing using the operation unit 72, the reconstruction processing unit 23 performs reconstruction processing on the X-ray projection data included in the newly designated time zone and range. Thus, new tomographic image data is generated. The display control unit 32 causes the display unit 71 to display a tomographic image based on the newly generated tomographic image data.

(Shooting conditions and scanogram)
Further, the photographing condition and the scanogram image may be displayed on the display unit 71 at the same time. An example of this display is shown in FIG. FIG. 8 is a diagram of a screen showing imaging conditions and a scanogram image. The display control unit 32 causes the display unit 71 to display a scanogram image 410 representing the upper surface of the subject and a scanogram image 420 representing the side surface of the subject. Further, the display control unit 32 causes the display unit 71 to display an imaging condition 300 in which a plurality of scan elements 301 to 305 are arranged in a table format (table format). Further, the display control unit 32 causes the display unit 71 to display a frame-shaped marker 411 in a range to be reconstructed in the scanogram image 410. Similarly, the display control unit 32 causes the display unit 71 to display a frame-shaped marker 421 in a range to be reconstructed in the scanogram image 420. Further, the display control unit 32 causes the display unit 71 to display the scan element that is the target of the reconstruction process in such a manner that it can be distinguished from other scan elements. For example, when the tomographic image data is reconstructed based on the X-ray projection data collected by the scan element 305, the display control unit 32 displays the column in which the scan element 305 is displayed and other scan elements are displayed. It can be discriminated from the existing column and displayed on the display unit 71. As an example, the display control unit 32 causes the display unit 71 to display a column in which the scan element 305 is displayed in a specific color set in advance.

  Further, as shown in FIG. 8, the display control unit 32 causes the display unit 71 to display input fields for inputting reconstruction conditions 310 such as an image slice thickness (Slice Thickness) and a slice interval (Slice Interval). Also good. The operator may input reconstruction conditions such as an image slice thickness (Slice Thickness), a slice interval (Slice Interval), a start position (Start Position), and an end position (End Position) using the operation unit 72 again. good. When the operator gives an instruction for reconstruction processing using the operation unit 72, the reconstruction processing unit 23 performs reconstruction processing on the X-ray projection data in accordance with the newly specified reconstruction condition, thereby creating a new Generate tomographic image data. Then, the display control unit 32 causes the display unit 71 to display a tomographic image based on the newly generated tomographic image data.

  As described above, according to the X-ray CT apparatus according to this embodiment, it is possible to visually grasp the entire examination by displaying the time change of the imaging conditions in a time chart, and was actually performed. It is possible to visually grasp the length of the photographing time and the timing at which each scan element is executed. Furthermore, in the time chart, it is possible to identify and display the time zone when the reconstructed image was collected, so that the reconstructed image is the image acquired at which time zone of the entire examination. It becomes possible to grasp visually.

(Editor 31)
The editing unit 31 causes the imaging protocol storage unit 50 to store the imaging conditions and the reconstruction conditions in the examinations executed in the past as new imaging protocols. For example, as illustrated in FIG. 9, the display control unit 32 causes the display unit 71 to display a time chart 100 representing temporal changes of the scan elements 110 to 140 included in one inspection executed in the past. Further, the display control unit 32 causes the display unit 71 to display a button 104 for requesting storage. The operator operates the button 104 using the operation unit 72 to request storage of past shooting conditions. The editing unit 31 receives a storage request from the user interface (UI) 70 and stores the past imaging conditions corresponding to the scan elements 110 to 140 in the imaging protocol storage unit 50 as a new imaging protocol. Further, the editing unit 31 may store the reconstruction conditions such as the image slice thickness and the slice interval in the examination executed in the past in the imaging protocol storage unit 50 by including them in the new imaging protocol.

(Change of shooting conditions)
Further, the editing unit 31 may change the imaging conditions and reconstruction conditions in the examinations executed in the past and store the changed imaging conditions and reconstruction conditions in the imaging protocol storage unit 50 as new imaging protocols. good. The function of the editing unit 31 will be described with reference to FIG. FIG. 10 is a view of a screen showing a time chart showing a time change of the tube current. The display control unit 32 causes the display unit 71 to display the time chart 100 representing the time change of the scan elements 110 to 140 included in one inspection executed in the past. Further, the display control unit 32 provides buttons 105 for requesting each instruction of addition (New), copying (Copy), pasting (Paste), and deleting (Delete) on the display unit 71 in units of scan elements. Display. The operator operates the button 105 using the operation unit 72 to add a new scan element to the scan elements 110 to 140, delete some scan elements, or change the order of the scan elements. . The editing unit 31 receives a change instruction from the user interface (UI) 70, and adds a new scan element to each scan element included in the past shooting conditions to be edited, or a part of scans. Create new shooting conditions by deleting elements or changing the order of scan elements. The editing unit 31 stores the newly created shooting condition in the shooting protocol storage unit 50 as a new shooting protocol. For example, when deleting some scan elements, the operator designates a scan element to be deleted using the operation unit 72 and further operates a delete button. The editing unit 31 receives an instruction to delete a scan element from the user interface (UI) 70, and deletes the designated scan element from among the scan elements included in the past imaging conditions that are to be edited. When a new scan element is added, the operator uses the operation unit 72 to specify a time zone to be added and further specify a tube current value. The editing unit 31 receives information indicating the time zone and the value of the tube current from the user interface (UI) 70, and adds a new scan element to the past imaging conditions to be edited.

  In addition, the operator may edit the photographing time and tube current value corresponding to each scan element using the operation unit 72. For example, the operator aligns a pointer with a pointing device (operation unit 72) such as a mouse on a frame-shaped figure representing a scan element whose condition is to be changed, a width corresponding to the length of the shooting time, and a tube Change the height corresponding to the current value. The editing unit 31 receives information indicating the changed shooting time and tube current value from the user interface (UI) 70, and changes the shooting time and tube current value of the scan element to be edited. To do. Then, the editing unit 31 stores the changed imaging condition in the imaging protocol storage unit 50 as a new imaging protocol.

  In addition, the editing unit 31 outputs the shooting condition as a result of editing to the processing unit 60. The time chart creation unit 61 creates a new time chart representing the time change of the shooting conditions according to the shooting conditions, and outputs data indicating the time chart to the display control unit 32. The display control unit 32 causes the display unit 71 to display a new time chart.

  Further, as shown in FIG. 8, the display control unit 32 causes the display unit 71 to display input fields for inputting reconstruction conditions such as an image slice thickness, a slice interval, a start position, and an end position. When the operator inputs reconstruction conditions such as an image slice thickness and a slice interval using the operation unit 72, information indicating the input reconstruction conditions is output from the user interface (UI) 70 to the editing unit 31. The The editing unit 31 receives a newly input reconstruction condition and changes a past reconstruction condition that is an object of editing. Then, the editing unit 31 causes the imaging protocol storage unit 50 to store the changed reconstruction condition as a new imaging protocol.

  As described above, time changes in shooting conditions are displayed in a time chart, and by editing the shooting conditions on the time chart, the operator can visually grasp the shooting conditions and intuitively set the shooting conditions. It becomes possible to change. Specifically, the operator can change the timing at which each scan element is executed while visually grasping the entire examination, and can set the length of the imaging time and the tube current value in each scan element. It becomes possible to change. In addition, by newly creating an imaging condition based on an actually performed imaging condition, it is possible to create an imaging condition corresponding to the individual difference of the subject.

  Further, the inspection may be executed after editing the imaging conditions and the reconstruction conditions. For example, the display control unit 32 causes the display unit 71 to display a button for requesting the execution of the inspection, and the operator uses the operation unit 72 to request the execution of the inspection. The control unit 30 receives an inspection execution request from the user interface (UI) 70 and executes the inspection according to the edited imaging protocol. Specifically, the control unit 30 outputs the edited shooting condition to the scan control unit 24. The scan control unit 24 performs imaging by controlling each unit in accordance with the imaging conditions corresponding to the scan element indicated by the edited time chart. In addition, the reconstruction processing unit 23 performs new reconstruction processing according to the edited reconstruction condition, thereby generating new tomographic image data.

(Display of data related to inspection)
In addition, the X-ray CT apparatus according to this embodiment may create data related to the inspection and display the data superimposed on the time chart. For example, a curve (Time Density Curve (hereinafter referred to as “TDC”)), an electrocardiogram waveform, or a respiratory waveform that represents the dark staining process of the contrast medium that has flowed into the subject is overlaid on the time chart as data related to the examination. To display. In this embodiment, as an example, a case where a TDC is created and displayed on a time chart will be described.

(Analysis unit 64)
For example, X-ray projection data at different times are acquired by injecting a contrast medium into the subject and continuously capturing images. The reconstruction processing unit 23 creates a plurality of tomographic image data with different taken times, and the data storage unit 22 stores a plurality of tomographic image data with different taken times. The analysis unit 64 reads a plurality of tomographic image data taken at different times from the data storage unit 22 via the management unit 40. Then, the analysis unit 64 sets a region of interest (ROI) for each tomographic image, and creates a curve (TDC) representing the temporal change of the contrast agent dark staining within the region of interest. For example, a curve representing a temporal change in luminance value (pixel value) is defined as TDC. In TDC, when a contrast agent flows into a tissue, the luminance value of the tissue increases. For this reason, the magnitude of the luminance value represents the state of dark staining of the contrast medium. Therefore, the TDC representing the time change of the luminance value in each part represents the time change of the contrast agent dark dyeing in each part (contrast dye deep dyeing process). The region of interest (ROI) can be specified by the operator using the operation unit 72. For example, the display control unit 32 displays a tomographic image on the display unit 71, and the operator designates a region of interest (ROI) on the tomographic image using the operation unit 72. Coordinate information indicating the position of the region of interest (ROI) on the tomographic image is output from the user interface (UI) 70 to the analysis unit 64 via the control unit 30. The analysis unit 64 receives the coordinate information of the region of interest (ROI) and creates a TDC in the region of interest (ROI).

  Then, the analysis unit 64 outputs data indicating TDC to the display control unit 32. The display control unit 32 displays the time on the time chart and the TDC time together on the display unit 71 simultaneously on the same time axis. An example of this display is shown in FIGS. FIG. 11 and FIG. 12 are diagrams of screens showing a time chart showing a time change of the tube current and a TDC showing a time change of the contrast agent dark staining.

  For example, as illustrated in FIG. 11, the display control unit 32 causes the display unit 71 to simultaneously display the time chart 100 representing the time change of the scan elements 110 to 140 and the TDC 500 on the same time axis. In the TDC 500, the horizontal axis represents time, and the vertical axis represents the luminance value. The display control unit 32 combines the time of the time chart 100 and the time of the TDC 500 and causes the display unit 71 to display simultaneously on the same time axis. By displaying the TDC 500 in this manner, the operator can change imaging conditions such as the timing at which each scan element is executed while referring to the contrast agent dark staining process. As described above, the operator operates the button 105 using the operation unit 72 to add a new scan element to the scan elements 110 to 140, delete some scan elements, Change the order. At this time, by referring to the TDC 500, the operator can set the imaging timing and the like in accordance with the contrast agent dark staining process. Since the TDC 500 is a curve representing the dark staining process of the contrast agent created based on actual imaging, the imaging conditions corresponding to individual differences of the subject can be changed by referring to the TDC 500 and changing the imaging conditions. It becomes possible to create. Then, as described above, the editing unit 31 accepts a change instruction from the user interface (UI) 70 and adds a new scan element to each scan element included in the past shooting conditions that are to be edited. Or by deleting some scan elements or changing the order of the scan elements. The editing unit 31 stores the newly created imaging condition in the imaging protocol storage unit 50 as a new imaging protocol.

  For example, when it is desired to perform shooting until immediately before the luminance value represented by the TDC 500 decreases, the operator can specify a desired time zone as the shooting time by extending the shooting time of the scan element to just before that. . For example, as illustrated in FIG. 12, by changing the timing at which the scan elements 110 to 140 are executed, it is possible to match the imaging timing with the contrast agent dark staining process indicated by the TDC 510.

  In addition, as shown in FIG. 12, the display control unit 32 causes the display unit 71 to display a button 107 for requesting storage. An operator operates the button 107 using the operation unit 72 to request storage of imaging conditions. The editing unit 31 receives a save request from the user interface (UI) 70, and stores each shooting condition corresponding to the scan elements 110 to 140 in the shooting protocol storage unit 50 as a new shooting protocol. In addition, the display control unit 32 causes the display unit 71 to display a button 106 for requesting execution of the inspection. The operator requests execution of the inspection by operating the button 106 using the operation unit 72. The control unit 30 receives an inspection execution request from the user interface (UI) 70 and executes the inspection according to the edited imaging protocol.

  As described above, by displaying the actually acquired TDC together with the time chart, it is possible to create shooting conditions with reference to information having individual differences. For example, the imaging timing can be matched with the contrast timing. As a result, it is possible to create imaging conditions tailored to individual subjects.

  In addition, according to the X-ray CT apparatus according to this embodiment, since it is possible to set the imaging timing in accordance with the contrast dyeing process with individual differences, the contrast agent concentration is increased before contrast imaging. Even without performing a test scan for grasping the dyeing process, it is possible to carry out photographing in time with the contrasting dark dyeing process. As a result, the burden on the subject can be reduced.

  In this embodiment, the TDC has been described as an example. However, instead of the TDC, an electrocardiogram waveform or a respiratory waveform may be displayed superimposed on the time chart. For example, an electrocardiographic waveform of the subject is acquired using an electrocardiograph, and the electrocardiographic waveform is input to the control unit 30. The display control unit 32 displays the time of the time chart and the time of the electrocardiogram waveform on the display unit 71 simultaneously on the same time axis. Further, the respiratory waveform of the subject is acquired using a respiratory device, and the respiratory waveform is input to the control unit 30. The display control unit 32 displays the time of the time chart and the time of the respiratory waveform on the display unit 71 simultaneously on the same time axis. The operator can edit the imaging conditions while referring to the electrocardiogram waveform and the respiratory waveform, so that it is possible to create imaging conditions corresponding to individual differences of the subject.

(Display of imaging part)
In addition, information indicating a part to be imaged may be displayed on a time chart representing a temporal change of the scan element. This display example will be described with reference to FIG. FIG. 13 is a diagram of a screen showing a time chart showing a time change of the tube current.

  For example, as illustrated in FIG. 13, the display control unit 32 causes the display unit 71 to display a time chart 100 </ b> A representing the time change of the scan elements 110 to 150. Further, the display control unit 32 causes the display unit 71 to display the part information indicating the imaging part included in the past imaging conditions in association with the scan elements 110 to 150. For example, when the scan elements 110 to 140 are photographing the head, the display control unit 32 displays “Head” as character information on the upper part of the frame-shaped figure representing the scan elements 110 to 140. . When the scan element 150 is photographing the neck, the display control unit 32 displays “Neck” as character information on the upper part of the frame-shaped figure representing the scan element 150.

  As described above, it is possible to intuitively understand which imaging was performed for which part by displaying information indicating the part to be imaged on the time chart. Become.

  The user interface (UI) 70 includes a display unit 71 and an operation unit 72. The display unit 71 includes a monitor such as a CRT or a liquid crystal display. Information such as a time chart, imaging conditions, and reconstruction conditions is displayed on the screen of the display unit 71. The operation unit 72 includes a pointing device such as a mouse or a trackball, a switch, various buttons, or a keyboard. The user interface (UI) 70 corresponds to an example of “designating means” of the present invention.

  Each of the reconstruction processing unit 23, the scan control unit 24, the control unit 30, the management unit 40, and the processing unit 60 includes a CPU (not shown) and a storage device (not shown) such as a ROM, a RAM, and an HDD. The storage device includes a reconfiguration program for executing the function of the reconfiguration processing unit 23, a scan control program for executing the function of the scan control unit 24, a control program for executing the function of the control unit 30, and a function of the management unit 40 And a processing program for executing the functions of the processing unit 60 are stored. The control program includes an editing program for executing the function of the editing unit 31 and a display control program for executing the function of the display control unit 32. The processing program includes a time chart creation program for executing the function of the time chart creation unit 61, a shooting condition screen creation program for executing the function of the shooting condition screen creation unit 62, and a reconstruction condition screen creation unit 63. A reconfiguration condition screen creation program for executing the above function and an analysis program for executing the function of the analysis unit 64 are stored. The function of each unit is executed by the CPU executing each program stored in the storage device.

(Operation)
Next, a series of operations by the X-ray CT apparatus according to this embodiment will be described with reference to FIGS. 14 and 15 are flowcharts showing a series of operations by the X-ray CT apparatus according to the embodiment of the present invention.

  First, the operation for specifying the reconstruction condition will be described with reference to FIG. The control unit 30 reads the shooting protocol from the shooting protocol storage unit 50 and outputs a plurality of shooting conditions corresponding to the plurality of scan elements to the scan control unit 24. The scan control unit 24 performs imaging by controlling each unit in accordance with each imaging condition corresponding to each scan element. In this embodiment, by performing dynamic scanning, a certain range having a width in the body axis direction of the subject is continuously imaged. By this dynamic scan, X-ray projection data obtained at different times is acquired, and the X-ray projection data is stored in the data storage unit 22. In addition, the management unit 40 adds information including the imaging conditions and the reconstruction conditions to the X-ray projection data as past examination information and stores the information in the data storage unit 22. In addition, the management unit 40 adds the patient ID and the examination ID to the X-ray projection data and stores them in the data storage unit 22. As described above, the management unit 40 causes the patient ID, the examination ID, and the examination information to be attached to the X-ray projection data and stored in the data storage unit 22.

(Step S01)
The operator uses the operation unit 72 to input the patient ID and examination ID of the patient to be examined. The patient ID and examination ID are output from the user interface (UI) 70 to the control unit 30. The control unit 30 outputs the input patient ID and examination ID to the management unit 40. The management unit 40 reads the examination information (imaging conditions and reconstruction conditions) attached with the patient ID and examination ID from the data storage unit 22 and outputs them to the control unit 30 and the processing unit 60.

(Step S02)
And the time chart preparation part 61 receives test | inspection information from the management part 40, and produces the time chart showing the time change of the past test | inspection information. For example, the time chart creation unit 61 creates a time chart that represents temporal changes of a plurality of scan elements included in one past examination. As an example, the time chart creation unit 61 creates a time chart that represents a temporal change in tube current included in the imaging conditions. Then, the time chart creation unit 61 outputs data indicating the time chart to the display control unit 32.

(Step S03)
The display control unit 32 receives data indicating the time chart from the time chart creation unit 61 and causes the display unit 71 to display the time chart. For example, as illustrated in FIG. 2, the display control unit 32 causes the display unit 71 to display a time chart 100 representing temporal changes of the scan elements 110 to 140 included in one inspection executed in the past.

  On the other hand, the imaging condition screen creation unit 62 receives inspection information from the management unit 40 and creates an imaging condition screen that represents past imaging conditions in a table format (table format). As an example, the imaging condition screen creation unit 62 creates an imaging condition screen that represents each scan element included in one past examination in a table format (table format). Then, the shooting condition screen creation unit 62 outputs data indicating the shooting condition screen to the display control unit 32. For example, as illustrated in FIG. 3, the display control unit 32 causes the display unit 71 to display an imaging condition 200 in which a plurality of scan elements 201 to 205 are arranged in a table format (table format). In addition, the reconstruction condition screen creation unit 63 receives the inspection information from the management unit 40 and creates a reconstruction condition screen representing past reconstruction conditions. As an example, the reconstruction condition screen creation unit 63 creates a reconstruction condition screen that represents information such as the image slice thickness, the reconstruction interval, the start position of the reconstruction range, and the end position of the reconstruction range. Then, the reconstruction condition screen creation unit 63 outputs data indicating the reconstruction condition screen to the display control unit 32. For example, as illustrated in FIG. 4, the display control unit 32 includes an image slice thickness (Slice Thickness), a reconstruction interval (Slice Interval), a reconstruction range start position (Start Position), and a reconstruction range end position ( A reconstruction condition 310 such as “End Position” is displayed on the display unit 71.

(Steps S04, S05)
Then, the operator gives an instruction to shift to the reconstruction processing mode using the operation unit 72 and designates the reconstruction condition. For example, when the operator gives a screen switching instruction using the operation unit 72, the display control unit 32 switches the time chart, the shooting condition screen, and the reconstruction condition screen to display on the display unit 71. The operator designates the reconstruction condition with reference to the information displayed on each screen. For example, as shown in FIG. 5, the operator uses the operation unit 72 to specify the start time of the time zone to be reconstructed by the first marker 102 on the time chart 100, and by the second marker 103. Specifies the end time of the time zone subject to reconstruction processing. In this way, the time zone to be reconfigured is designated. Further, the operator uses the operation unit 72 to input conditions such as an image slice thickness, a slice interval, a start position, and an end position. When the reconstruction condition is specified in this way, the reconstruction condition is output from the user interface (UI) 70 to the control unit 30.

(Step S06)
The control unit 30 outputs the reconstruction condition specified by the operator to the reconstruction processing unit 23 and requests the reconstruction processing unit 23 to perform the reconstruction process. The reconstruction processing unit 23 reads the X-ray projection data collected in the time zone to be subjected to the reconstruction process included in the reconstruction condition from the data storage unit 22, and the image slice thickness and the slice interval included in the reconstruction condition The tomographic image data is generated by performing reconstruction processing according to the conditions such as. Then, the reconstruction processing unit 23 outputs the reconstructed tomographic image data to the display control unit 32.

(Step S07)
The display control unit 32 receives tomographic image data from the reconstruction processing unit 23 and causes the display unit 71 to display a tomographic image based on the tomographic image data. For example, as illustrated in FIG. 6, the display control unit 32 causes the display unit 71 to display a list 400 of a plurality of tomographic images generated by the reconstruction process. Further, the display control unit 32 causes the display unit 71 to display the time chart 100 configured by the scan elements 110 to 140 representing the time change of the tube current. Then, based on the information indicating the time zone that is the target of the reconstruction process, the display control unit 32 makes it possible to distinguish the scan element included in the time zone from the other scan elements in the time chart 100. 71 is displayed. For example, when the tomographic image data is reconstructed based on the X-ray projection data collected by the scan element 130, the display control unit 32 displays the scan element 130 in a specific color set in advance as shown in FIG. It is displayed on the display unit 71.

  As described above, by displaying the time chart 100 representing the time change of the imaging conditions, it is possible to visually grasp the entire inspection actually performed, and the timing at which each scan element is executed. Can be grasped visually. Further, by making it possible to specify the time zone that is the target of the reconstruction process on the time chart 100, it is possible to visually grasp the desired time zone and specify it intuitively. Furthermore, it becomes possible to visually grasp which reconstructed image is an image acquired by which scan element of the entire examination.

  Next, a process for registering inspection conditions of inspections executed in the past as a new imaging protocol will be described with reference to FIG.

(Step S10)
Similar to step S01 described above, the operator uses the operation unit 72 to input the patient ID and examination ID of the patient to be examined. The management unit 40 reads the examination information (imaging conditions and reconstruction conditions) attached with the patient ID and examination ID from the data storage unit 22 and outputs them to the control unit 30 and the processing unit 60.

(Step S11)
Similar to step S02 described above, the time chart creation unit 61 creates a time chart representing a temporal change in past examination information. For example, the time chart creation unit 61 creates a time chart that represents time changes of a plurality of scan elements included in one past examination. As an example, the time chart creation unit 61 creates a time chart that represents a temporal change in tube current.

(Step S12)
Similar to step S03 described above, as shown in FIG. 2, the display control unit 32 displays on the display unit 71 a time chart 100 representing the time change of the scan elements 110 to 140 included in one inspection executed in the past. Let The shooting condition screen creation unit 62 creates a shooting condition screen that represents past shooting conditions in a table format (table format). Also, the reconstruction condition screen creation unit 63 creates a reconstruction condition screen that represents past reconstruction conditions. The display control unit 32 switches the time chart, the imaging condition screen, and the reconstruction condition screen to be displayed on the display unit 71 in accordance with a switching instruction from the user interface (UI) 70.

(Steps S13, S14, S15)
Then, the operator gives an instruction to shift to the reconstruction processing mode using the operation unit 72 (step S13). Further, when the operator requests to shift to the edit mode using the operation unit 72 (step S14), the control unit 30 switches the processing mode to the edit mode (step S15). On the other hand, when the operator uses the operation unit 72 to request the end of the process, the control unit 30 ends the process.

(Steps S16 and S17)
When shifting to the edit mode, the control unit 30 waits for an input from the user interface (UI) 70, and when receiving the input, executes a process corresponding to the input.

(Steps S18 and S20)
For example, when the operator uses the operation unit 72 to instruct TDC capture, the control unit 30 instructs the processing unit 60 to create TDC. When the analysis unit 64 receives the instruction from the control unit 30, the analysis unit 64 reads a plurality of tomographic image data with different times taken from the data storage unit 22 via the management unit 40. Then, the analysis unit 64 sets a region of interest (ROI) for each tomographic image, and creates a curve (TDC) representing the temporal change in the contrast agent concentration in the region of interest (step S18). As an example, the analysis unit 64 creates a curve representing a temporal change in luminance value as TDC. Then, the display control unit 32 causes the display unit 71 to display the time chart and the TDC simultaneously on the same time axis (step S20). For example, as illustrated in FIG. 11, the display control unit 32 causes the display unit 71 to simultaneously display the time chart 100 representing the time change of the scan elements 110 to 140 and the TDC 500 on the same time axis. Further, the display control unit 32 may display the electrocardiogram waveform and the respiratory waveform of the subject superimposed on the time chart instead of the TDC. For example, the display control unit 32 causes the display unit 71 to display a selection screen for allowing the operator to select data related to the examination. As an example, the display control unit 32 displays a selection screen for selecting a TDC, an electrocardiogram waveform, and a respiratory waveform on the display unit 71, and the operator uses the operation unit 72 to select desired data from the selection screen. Is specified. The display control unit 32 causes the display unit 71 to display the selected data. After displaying TDC or the like, the process returns to step S16, and the control unit 30 waits for an input from the user interface (UI) 70. When receiving the input, the control unit 30 executes a process according to the input.

(Steps S19 and S20)
When the operator changes conditions such as an imaging condition and a reconstruction condition using the operation unit 72, the editing unit 31 changes the imaging condition and the reconstruction condition in the examination performed in the past according to the change (step) S19). For example, as illustrated in FIG. 10, the display control unit 32 causes the display unit 71 to display a time chart 100 representing temporal changes of the scan elements 110 to 140 included in one inspection executed in the past. The operator uses the operation unit 72 to instruct to add, delete, or change the order of scan elements. The editing unit 31 receives a change instruction from the user interface (UI) 70 and edits a scan element included in the past shooting conditions to be edited, thereby creating a new shooting condition. Further, the operator may edit the photographing time and the tube current value in each scan element by using the operation unit 72. Further, as shown in FIG. 8, the display control unit 32 causes the display unit 71 to display input fields for inputting reconstruction conditions such as an image slice thickness and a slice interval, and the operator uses the operation unit 72. A desired reconstruction condition may be input. Then, the display control unit 32 displays the changed imaging conditions and reconstruction conditions on the display unit 71 (step S20). After changing the conditions, the process returns to step S16, and the control unit 30 waits for an input from the user interface (UI) 70, and when receiving the input, executes the process according to the input.

(Steps S21 and S22)
When the operator requests the execution of the inspection using the operation unit 72, the control unit 30 receives the request from the user interface (UI) 70 and shifts to the inspection execution mode (step S21). For example, the control unit 30 outputs the edited shooting condition to the scan control unit 24, and the scan control unit 24 performs shooting by controlling each unit according to the scan element indicated by the edited time chart (step S22). ).

(Steps S23 and S24)
When the operator uses the operation unit 72 to request the saving of the editing result, the editing unit 31 uses the newly created imaging condition and reconstruction condition after editing as a new imaging protocol. 50 (step S23). When the operator requests the end of the edit mode using the operation unit 72, the control unit 30 receives the request from the user interface (UI) 70, ends the edit mode, and shifts to the reconstruction processing mode ( Steps S24 and S13).

  As described above, by editing the shooting conditions on the time chart, the operator can visually grasp the shooting conditions and intuitively change the shooting conditions. For example, the operator can change the timing of individual imaging, the length of imaging time, the value of tube current, and the like while visually grasping the entire examination. In addition, by newly creating an imaging condition based on an actually performed imaging condition, it is possible to create an imaging condition corresponding to the individual difference of the subject. For example, it is possible to visually edit the imaging timing and the like while referring to the contrast medium dark staining process, the electrocardiogram waveform, and the respiratory waveform on the time chart.

1 is a block diagram showing an X-ray CT apparatus according to an embodiment of the present invention. It is a figure of the screen which shows the time chart showing the time change of a tube current. It is a figure which shows the imaging | photography condition screen which shows imaging | photography conditions in a table format. It is a figure which shows the reconstruction condition screen showing a reconstruction condition. It is a figure of the screen which shows the time chart showing the time change of a tube current. It is a figure of the screen which shows a tomogram and a time chart. It is a figure of the screen which shows a scanogram image and a time chart. It is a figure of the screen which shows imaging | photography conditions and a scanogram image. It is a figure of the screen which shows the time chart showing the time change of a tube current. It is a figure of the screen which shows the time chart showing the time change of a tube current. It is a figure of the screen which shows the time chart showing the time change of a tube current, and TDC showing the time change of the deep dyeing of a contrast agent. It is a figure of the screen which shows the time chart showing the time change of a tube current, and TDC showing the time change of the deep dyeing of a contrast agent. It is a figure of the screen which shows the time chart showing the time change of a tube current. It is a flowchart which shows a series of operation | movement by the X-ray CT apparatus which concerns on embodiment of this invention. It is a flowchart which shows a series of operation | movement by the X-ray CT apparatus which concerns on embodiment of this invention. It is a figure of the screen which shows the example of a display of the test | inspection information based on a prior art. It is a figure of the screen which shows the example of a display of the test | inspection information based on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mounting device 20 Console part 21 Pre-processing part 22 Data storage part 23 Reconfiguration | reconstruction process part 24 Scan control part 30 Control part 31 Editing part 32 Display control part 40 Management part 50 Imaging protocol memory | storage part 60 Processing part 61 Time chart preparation part 62 Imaging condition screen creation unit 63 Reconfiguration condition screen creation unit 64 Analysis unit 70 User interface (UI)
71 Display unit 72 Operation unit 80 Couch device 81 Couch 82 Couch control unit

Claims (10)

An X-ray source;
An X-ray detector disposed opposite to the X-ray source across the subject;
Scan control means for performing imaging by exposing X-rays from the X-ray source according to imaging conditions that change with time;
Reconstruction processing means for generating image data by performing reconstruction processing in accordance with preset reconstruction conditions for the X-ray projection data acquired by the imaging;
A time chart creating means for creating a time chart representing a time change of examination information including the imaging condition and the reconstruction condition;
Display control means for displaying the time chart, the imaging conditions, and the reconstruction conditions on a display means;
Designating means for designating a new reconstruction condition on the time chart displayed on the display means and on the screen displaying the reconstruction condition;
Have
The X-ray CT apparatus, wherein the reconstruction processing means generates new image data by performing a reconstruction process in accordance with the specified new reconstruction condition. An editing unit that receives an instruction to change the inspection information on the time chart displayed on the display unit, and changes the inspection information;
Storage means for storing the changed examination information,
The X-ray CT apparatus according to claim 1, wherein the scan control unit performs the imaging according to an imaging condition included in the changed examination information. Analysis that generates a curve representing a process in which the contrast agent is deeply stained in the subject based on X-ray projection data acquired by performing the imaging in a state where the contrast agent is injected into the subject. Further comprising means,
The X-ray CT apparatus according to claim 2, wherein the display control unit causes the display unit to display a curve representing the process of the deep dyeing on the same time axis as the time chart.   The X-ray according to claim 2, wherein the display control unit receives an electrocardiogram waveform or a respiratory waveform obtained from the subject and causes the display unit to display the waveform on the same time axis as the time chart. CT device.   The reconstruction processing means, when a time zone to be reconstructed on the time chart displayed on the display means is designated by the designation means, X-rays acquired in the designated time zone The X-ray CT apparatus according to claim 1, wherein the image data is generated based on projection data.   The display control unit causes the display unit to display an image based on the image data generated under the new reconstruction condition, and further displays a time zone in which the image data is generated on the time chart. The X-ray CT apparatus according to claim 5, wherein the X-ray CT apparatus is displayed in a distinguishable manner.   The time chart creation means creates the time chart by representing a scan sequence in which a plurality of scan elements controlled by a plurality of imaging conditions are ordered by a time change of a tube current supplied to the X-ray source. The X-ray CT apparatus according to claim 1, wherein: The time chart creation means creates the time chart by representing a scan sequence in which a plurality of scan elements controlled by a plurality of imaging conditions are ordered as a time change of a tube current supplied to the X-ray source,
The designation means designates a scan element to be reconstructed on the time chart displayed on the display means,
The reconstruction processing means, when a scan element to be reconstructed on the time chart displayed on the display means is designated by the designation means, X-rays acquired by the designated scan element The X-ray CT apparatus according to claim 1, wherein the image data is generated based on projection data.   The display control means causes the display means to display an image based on the image data generated under the new reconstruction condition, and further to identify the designated scan element on the time chart. The X-ray CT apparatus according to claim 8, wherein the display means displays the image.   The display control means causes the display means to display a positioning image acquired in advance, and enables the range of the subject to be subjected to the reconstruction process to be identified in the positioning image. The X-ray CT apparatus according to claim 1, wherein the X-ray CT apparatus is displayed.