JP2007007255A - X-ray ct apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray CT apparatus capable of setting a favorable scanning plan while reducing the X-ray dose of a subject and simplifying the labor of an operator. <P>SOLUTION: The operator sets a reference point on the subject and installs a reference marker on the reference point (S2). An image processor 27 generates a past scanogram image (S3). A video camera 5 generates a camera image showing the external appearance of the subject (S5), a reading part 7a reads in the both images (S6), a positioning part 7b positions the past scanogram image and the camera image (S7), and a setting part 7c sets the scanning plan (S8). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an X-ray CT apparatus, and more particularly to an X-ray CT apparatus that reduces X-ray exposure by scanogram imaging.

  Conventionally, in order to determine the range in which scan imaging is performed with an X-ray CT apparatus, scanogram imaging in which the X-ray source is stationary (not rotated) and only the bed on which the subject is placed is moved in the body axis direction of the subject. Then, a scanogram image that is a planar perspective image is generated. Then, the operator (photographer) sets the start position and the end position of the scan photographing based on the scanogram image.

  However, it is preferable that the X-ray exposure dose of the subject is as small as possible. Therefore, a technique for setting a scan shooting position based on a video image shot by a video camera instead of the scanogram image is disclosed.

  For example, the medical image diagnostic apparatus disclosed in Patent Document 1 includes an indicator that includes a point light source that indicates, with an optical marker, a site where a tomographic image of a subject laid on a bed is to be obtained. Then, the coordinates of the indicator on the device are calculated based on the video image obtained by photographing the subject indicated by the optical marker with the video camera, and the bed until the part of the subject coincides with the position of the X-ray detector. Determine the amount of movement.

  Further, the medical image diagnostic apparatus of Patent Document 2 is displayed with a camera image imaging unit that captures an appearance of a specific part of a subject that is placed on a bed, and a display unit that displays the captured camera image. Calculating an amount of displacement of the bed or gantry necessary to match the indicated imaging cross-sectional portion with the position of the detector in the gantry on the camera image. A subject positioning control device having central processing means for controlling the displacement operation of the bed or gantry. Thus, it is possible to instruct an imaging cross section based on the camera image and to perform scanning imaging at a desired imaging cross section position.

Furthermore, the X-ray CT apparatus of Patent Document 3 drives the video camera, and the operator gantry the table while observing the slice planning CRT so that the imaging unit of the subject is in the vicinity of the imaging imaging region of the video camera. Move to opening. In this X-ray CT apparatus, a slice plan is made on a subject image in a slice planning CRT, and a gantry and a table operation amount necessary for tomography are calculated from the set cursor position. When the calculation of the movement amount is completed, the control unit moves the gantry and the table by the calculated movement amount via the controller.
JP-A-8-126638 JP-A-9-31475 JP 2001-286465 A

  When making a scan plan, it is more preferable to refer to the form (skeleton, etc.) of the subject in the body, but there is a problem that the X-ray exposure amount of the subject increases when scanogram imaging is performed every time. In addition, there is a problem that setting a scan plan every time is time-consuming for the operator.

  The present invention has been made in view of such circumstances, and it is possible to set a more preferable scan plan while reducing the amount of X-ray exposure of the subject, and to simplify the labor of the operator. An object is to provide a line CT apparatus.

  In order to achieve the above object, an X-ray CT apparatus according to the present invention is arranged to face an X-ray source that irradiates an X-ray and an X-ray source across a subject and detect the X-ray. An X-ray detector that outputs X-ray transmission data, a rotating means that can be rotated by mounting the X-ray source and the X-ray detector, and a tomographic image is reconstructed based on the X-ray transmission data Image processing means, scanning means obtained by taking a scanogram of the subject, reading means for reading a camera image obtained by photographing the subject with an optical camera, and positions of the scanogram image and the camera image Alignment means for performing alignment, setting means for setting a scan plan based on the aligned scanogram image, and the tomographic image, scanogram together with the set scan plan Ram images, and a display means for displaying at least one of the camera image.

  Here, “scan” refers to measurement imaging for collecting X-ray transmission data necessary for the X-ray CT apparatus to reconstruct a tomographic image.

  The “scan plan” refers to scan conditions such as a scan start position and a scan end position, a field of view (FOV), a scan interval, and the like for determining a range for reconstructing a tomographic image. It means making a decision.

  Further, the reading means reads a past camera image obtained by photographing the subject with an optical camera in the past and a current camera image photographed currently, and the display means together with the set scan plan, the tomographic image, At least one of the past camera image, the current camera image, or an arbitrary cross-sectional image is displayed.

  In addition, the X-ray CT apparatus further includes a marker providing unit that provides an optical marker that indicates a reference point for alignment in the subject, and the alignment unit includes a reference that indicates the reference point included in the scanogram image. The scanogram image and the camera image are aligned based on the marker and the optical marker included in the camera image, or based on the optical marker included in the past camera image and the current camera image, respectively. The past camera image and the current camera image are aligned.

  The reading means reads a past scanogram image obtained by imaging the subject in the past and a current scanogram image newly obtained by scanning the scanogram, and the display means is set as described above. Along with the scan plan, at least one of the tomographic image, the past scanogram image, or the current scanogram image is displayed.

  The X-ray CT apparatus is arranged to face an X-ray source that irradiates X-rays and the X-ray source across a subject, detects the X-rays, and outputs X-ray transmission data. An X-ray detector, an X-ray source and an X-ray detector that can be rotated and rotated, an image processing unit that reconstructs a tomographic image based on the X-ray transmission data, and an optical test object Reading means for reading a past camera image captured by the camera in the past and a current camera image captured at the present, and a three-dimensional image obtained by setting a scan plan based on the past camera image and performing a scan shooting Cross-sectional image generating means for generating an arbitrary cross-sectional image based on three-dimensional image data associated with shooting position information of the past camera image, the current camera image, the past camera image, and the arbitrary cross-section Position with the image An alignment unit that performs correction, a setting unit that sets a scan plan based on the aligned arbitrary cross-sectional image, the tomographic image, the past camera image, the current camera image, or the arbitrary cross-sectional image Display means for displaying at least one.

  Further, the setting means may set a scan plan by diverting a scan plan set based on the scanogram image or a scan plan set based on the past camera image.

  The X-ray CT apparatus is arranged to face an X-ray source that irradiates X-rays and the X-ray source across a subject, detects the X-rays, and outputs X-ray transmission data. A X-ray detector, an X-ray source and an X-ray detector, a rotatable rotating unit, an image processing unit for reconstructing a tomographic image based on the X-ray transmission data, and the subject in the past Reading means for reading a past scanogram image obtained by taking a scanogram and a current scanogram image newly obtained by taking a scanogram, and a position for aligning the past scanogram image and the current scanogram image A matching unit; a setting unit that sets a scan plan for newly performed scan photography by diverting a scan plan set based on the past scanogram image; the tomographic image; the past Kyanoguramu comprising image or a display means for displaying at least one of the current scanogram image.

  Further, the X-ray CT apparatus reads a scanogram image obtained by scanning a subject with a scanogram, a camera image obtained by photographing the subject with an optical camera, and the scanogram image and the camera image. You may comprise the control program which makes a computer perform the step which performs position alignment, and the step which sets a scanning plan based on the said scanogram image with which position alignment was carried out.

  In addition, the X-ray CT apparatus reads a past camera image obtained by imaging the subject with an optical camera in the past and a current camera image currently taken, and sets and scans the scan based on the past camera image. Three-dimensional image data obtained by photographing, generating an arbitrary cross-sectional image based on three-dimensional image data associated with photographing position information of the past camera image, and the past camera image, A control program for causing a computer to execute a position alignment between the current camera image and the arbitrary cross-sectional image and a step of setting a scan plan based on the aligned arbitrary cross-sectional image may be configured. Good.

  According to the present invention, the position of a camera image obtained by photographing an object with an optical camera is matched with a scanogram image or an arbitrary cross-sectional image obtained by performing scanogram photography of the object in the past. Therefore, it is possible to provide an X-ray CT apparatus capable of setting a scan plan while referring to the internal form of the subject while reducing the X-ray exposure amount of the subject and simplifying the labor of the operator. it can.

  Hereinafter, preferred embodiments of an X-ray CT apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

<Hardware configuration>
A schematic hardware configuration of an X-ray CT apparatus to which the present invention is applied will be described with reference to FIGS.

  FIG. 1 is an overall view of the X-ray CT apparatus 1. The X-ray CT apparatus 1 includes a scanner 2, a patient table 3 on which a subject is placed, a top 4 of the patient table 3, a video camera 5, a light 6, a console 7, a display device 8, and an operation device 9.

  FIG. 2 is a block diagram of the X-ray CT apparatus 1. The scanner 2 includes an X-ray source 11 that emits X-rays, an X-ray detector (hereinafter referred to as “detector”) 14 that detects X-rays emitted from the X-ray source 11, and the X-ray source 11 and the detector 14. And a turntable 16 for rotating. The X-ray tube control apparatus 10 controls the amount of X-rays emitted from the X-ray tube 11 by controlling the tube voltage and tube current. The collimator control device 12 controls the collimator 13. The collimator 13 adjusts the X-ray irradiation angle, and the subject 20 is irradiated with the X-ray adjusted by the collimator 13.

  The detector 14 detects X-rays that have passed through the subject 20. The detector 14 is disposed so as to face the X-ray tube 11 across the subject, and outputs X-ray transmission data to the data acquisition device 15 based on the detected X-rays.

  The data collection device 15 collects the X-ray transmission data detected by the detector 14 and transmits it to the console 7. The X-ray transmission data is stored in the storage device 71.

  The turntable 16 is rotated by the driving force transmitted from the turntable driving device 18 through the driving force transmission system 19. The rotation control device 17 controls the turntable driving device 18.

  The patient table 3 carries the subject 20 placed on the top 4 into and out of the X-ray irradiation space in the opening 21 of the scanner 2. The patient table control device 22 controls the patient table vertical movement device 23 and the top plate driving device 24. The patient table vertical movement device 23 moves the patient table 3 in the vertical direction. The top plate driving device 24 moves the top plate 4 in the body axis direction.

  The video camera 5 is an optical camera that captures the appearance of the subject. The optical camera may be a digital camera in addition to the video camera 5. Further, the position of the optical camera may be installed on the opening surface of the opening 21 as shown in FIG. 1 or may be installed by being hung from the ceiling in the room where the X-ray CT apparatus is set. Hereinafter, the “image of the appearance of the subject taken by the optical camera” is referred to as “camera image”.

  The light 6 is an indicator that provides an optical marker that indicates a reference point for alignment in a subject to be described later. The light 6 includes a light emitting element such as an LED element, and applies an optical marker by irradiating light from the light emitting element to a reference point of a subject.

  In addition, in order to instruct | indicate a reference point, what is necessary is just the marker which can be visually recognized not only with the light 6 but a camera image, such as a sign pen and a sticker.

  Alternatively, a part of the subject placed on the top 4 (for example, the top of the head) may be set as the measurement reference position, and the reference point may be set based on the distance from the measurement reference position.

  The console 7 includes a storage device 71, a system control device 72, an image processing device 73, and a scan planning device 74. The storage device 71, the system control device 72, the image processing device 73, and the scan planning device 74 are connected to each other. The

  The storage device 71 stores scanogram images, tomographic images, various data, programs for realizing the functions of the X-ray CT apparatus 1, and the like.

  The system control device 72 includes the scanner 2 (X-ray tube control device 10, collimator control device 12, data collection device 15, rotation control device 17), patient table 3 (patient table control device 22), video camera 5, and light 6. Control. Further, the system control device 72 performs control for storing the X-ray transmission data collected by the data collection device 15 and the image data acquired by the video camera 5 in the storage device 71.

  The image processing device 73 reconstructs a tomographic image (CT image) or generates a scanogram image based on the X-ray transmission data collected by the data collection device 15. The scanogram image is an X-ray transmission image for setting a scan plan to be described later.

  In addition, the image processing device 73 associates the camera image of the subject with the scanogram image, and performs alignment for aligning the positions of these images. Details regarding the alignment processing will be described later.

  The scan planning device 74 reads a scanogram image, a camera image, etc. of the subject from the storage device 71 and displays them on the display device 8. The operator uses the operation device 9 to set a scan plan on an image such as a displayed scanogram image or camera image. The set scan plan is stored in the storage device 71.

  The scan planning device 74 outputs information related to the scan plan to the system control device 72. The system control device 72 performs control for determining the positions of the rotary plate 16 of the scanner 2 and the top plate 4 on which the subject is placed so that X-ray transmission data corresponding to the scan plan is acquired.

  The display device 8 and the operation device 9 are connected to the console 7. The display device 8 displays a tomographic image, a scanogram image, a camera image, various information handled by the system control device 72, and the like. The operation device 9 is a mouse, a keyboard, or the like, and is operated by an operator. The operation device 9 inputs various instructions and information by the operator to the system control device 72 and the image processing device 73.

<First embodiment>
In the first embodiment, the operator sets a scan plan using the current camera image (current camera image) and scanogram image of the subject.

  Next, the configuration of the control program according to the present embodiment will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the control program.

  The control program includes a reading unit 7a, an alignment unit 7b, and a setting unit 7c. The reading unit 7a reads a scanogram image obtained by taking a scanogram of the subject and a camera image obtained by taking the subject with an optical camera. The alignment unit 7b performs alignment between the scanogram image and the camera image. The setting unit 7c sets a scan plan based on the aligned scanogram image.

  The control program is stored in the storage device 71 of the console 7. The image processing device 73 reads and executes the reading unit 7a and the alignment unit 7b from the storage device 71. The scan planning device 74 reads the setting unit 7c from the storage device 71 and executes it.

  Hereinafter, processing according to the present embodiment will be described with reference to FIGS. FIG. 4 is a flowchart showing the flow of processing according to this embodiment. FIG. 4 is a diagram showing an image display example in each step of the flowchart of FIG.

(Step S1)
In S1, it is determined whether or not the reference image of the subject to be referred to for setting the scan position exists in the storage device 71 (S1). In the present embodiment, the reference image is a scanogram image. If there is no scanogram image (first scan photographing), the process proceeds to S2. If there is a scanogram image (the next and subsequent scans), the process proceeds to S4.

(Step S2)
In S2, the operator arbitrarily sets three characteristic parts on the surface of the subject's body. The feature of these three parts is that there is little change in the position of the subject due to changes in body shape over time, respiration during imaging, and the like. Specifically, the three sites are preferably near the clavicle or the rib. These three parts are used as reference points for aligning a scanogram image and a camera image, which will be described later. Hereinafter, the set three parts are referred to as “reference points”.

  The operator installs reference markers indicating the reference points at the three reference points of the subject (S2). The reference marker is a material that does not transmit X-rays, for example, a sufficiently small object having a circular shape.

  In the following, as an example of three reference points, a case where the lower part of the ribs on both sides and the lower ends of the ribs on both sides is set will be described. FIG. 5A is a diagram illustrating an example of a state where a reference marker is added to the body of the subject. A, B, and C in FIG. 5A are reference points. A is a reference point at the lower end of the collarbone, and B and C are reference points at the lower end of the rib. In all the drawings of FIG. 5, A, B, and C indicate reference points.

  Note that the number of reference points is not limited to three, but may be arbitrary as long as the scanogram image and the camera image can be aligned.

(Step S3)
In S3, the scanner 2 scans the subject whose reference point is indicated by the reference marker. The image processing device 25 generates a scanogram image (planar transmission image) (S3). FIG. 5B is a diagram illustrating an example of a scanogram image of a subject obtained by performing scanogram imaging with a reference marker. The system control device 72 stores the generated scanogram image in the storage device 71. This scanogram image is a scanogram image generated in the past than when a camera image was captured in S5 described later.

(Step S4)
In S4, the light 6 indicates the reference point of the subject set in S2. The light 6 indicates the reference point by irradiating the reference point of the subject with light. That is, a point light source (optical marker) is set as a reference point (S4). FIG. 5C is a diagram showing an example of the appearance of a subject whose reference point is indicated by the optical marker.

(Step S5)
In S5, the video camera 5 captures the appearance of the subject and generates a camera image (S5). FIG. 5D is a diagram illustrating an example of a camera image of a subject whose reference point is indicated by the optical marker.

(Step S6)
In S6, the reading unit 7a reads a scanogram image obtained by taking a scanogram of the subject and a camera image obtained by taking the subject with an optical camera (S6).

(Step S7)
In S7, the alignment unit 7b performs alignment between the scanogram image and the camera image (S7). The alignment unit 7b is a position of the reference marker (A, B, C in FIG. 5B) included in the scanogram image and the optical marker included in the camera image (A, B, C in FIG. 5D). To match. FIG. 5E is a diagram for explaining alignment between a scanogram image and a camera image. The alignment unit 7b corrects the position of the image by enlarging / reducing or rotating the image using affine transformation, and aligns the positions of both images.

(Step S8)
In S8, the setting unit 7c sets a scan plan based on the aligned scanogram image (S8). FIG. 5F is a diagram for explaining setting of the scan position on the past scanogram image. A line segment s in the figure indicates the set scan position.

  If the operator diverts a past scan plan, for example, a scan plan set at the time of generating a scanogram image, and sets the scan position to the same position as the past, it is possible to perform scan imaging of the same part as the past. The past scan plan is stored in the storage device 71, and the scan plan device 74 can appropriately read the stored past scan plan.

  Note that the operator may manually set the scan start position, the scan end position, and the like on the scanogram image without using the past scan plan.

  The scan planning device 74 processes the set scan position information (scan plan).

(Step S9)
In S8, the system control device 72 controls the scanner 2 based on the scan plan set in S8. The scanner 2 performs scan shooting. The image processing device 73 reconstructs the tomographic image (S9) and ends. The display device 8 displays the tomographic image on the display device 8. FIG. 5G shows an example of a reconstructed tomographic image.

  Although the gantry type X-ray CT apparatus has been described above, a C-arm type X-ray CT apparatus may be used.

  According to the present embodiment, the scanogram image of the subject and the camera image can be aligned. By using a scanogram image whose position is aligned with the camera image, the operator can grasp the form of the body of the subject and set a scan plan. Further, by diverting the past scan plan, the labor of the operator can be simplified. Further, it is not necessary to perform scanogram imaging of the subject every time an X-ray CT image is acquired. Therefore, the X-ray exposure amount of the subject is reduced.

<Second embodiment>
In the second embodiment, a past camera image (past camera image) of a subject taken by the video camera 5 is used as a reference image. Next, the configuration of the control program according to the present embodiment will be described with reference to FIG. FIG. 6 is a block diagram showing the configuration of the control program. The control program includes a reading unit 7d, an MPR image generation unit 7e, an alignment unit 7f, and a setting unit 7g.

  The reading unit 7d reads a scanogram image obtained by photographing a subject with a scanogram and a camera image obtained by photographing the subject with an optical camera.

  The MPR image generation unit 7e is three-dimensional image data obtained by setting a scan plan based on a past camera image and performing scan photographing, and is associated with the photographing position information of the past camera image. An arbitrary cross-sectional image (MPR image) is generated based on the image data.

  The alignment unit 7f performs alignment between the scanogram image and the camera image.

  The setting unit 7g sets a scan plan based on the aligned scanogram image.

  The control program is stored in the storage device 71. The image processing device 73 reads and executes the reading unit 7a, the alignment unit 7b, and the MPR image generation unit 7e from the storage device 71. The scan planning device 74 reads the setting unit 7c from the storage device 71 and executes it.

  Hereinafter, processing according to the present embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing the flow of processing.

(Step S701)
In S701, it is determined whether or not a past camera image as a reference image exists in the storage device 71 (S701). If there is no past camera image (first scan shooting), the process proceeds to S702. If there is a past camera image (scan shooting after the next time), the process proceeds to S704.

(Step S702)
In S702, the operator sets a reference point on the body surface of the subject. Then, the light 6 sets the optical marker at three reference points of the subject (S702).

(Step S703)
In step S <b> 703, the video camera 5 generates a camera image (past camera image) as a reference image by photographing the appearance of the subject. The system control device 72 stores the past camera image in the storage device 71 (S703). Note that the camera image (past camera image) of this step is generated in the past than when the current camera image was shot in S705.

(Step S704)
In S704, the operator resets the reference point on the surface of the subject's body at the same position as S702. The optical marker is reset to the three reference points of the subject by the light 6 (S704).

(Step S705)
In S705, the video camera 5 regenerates the current camera image (current camera image) of the subject (S705).

(Step S706)
In S706, the reading unit 7d reads the past camera image generated in S703 and the current camera image currently captured (S706).

(Step S707)
In S706, the MPR generation unit 7e generates an arbitrary cross-sectional image (MPR image) based on the three-dimensional image data associated with the shooting position information of the past camera image (S707).

(Step S708)
In S708, the alignment unit 7f aligns the past camera image, the current camera image, and the MPR image (S708).

  The alignment unit 7f aligns both images based on optical markers included in the past camera image and the current camera image, respectively. In S707, the positional relationship between the MPR image and the past camera image has already been handled. Therefore, the positions of the MPR image and the current camera image can be matched via the past camera image.

(Step S709)
In S709, the setting unit 7g sets a scan plan based on the aligned MPR image (S709). When the operator diverts the past scan plan, the scan imaging of the same part as the past can be performed. The past scan plan is stored in the storage device 71, and the scan plan device 74 can appropriately read the stored past scan plan.

  Further, the operator may use the operation device 9 to set the scan position without diverting the past scan plan.

  If the process proceeds to S709 via S703, the scan plan is set based on the past camera image. In this embodiment, the video camera 5 is fixedly installed with respect to the detector 14, and the positional relationship between the video camera 5 and the detector 14 is known. Therefore, the system control device 72 can perform control for determining the positions of the rotary plate 16 of the scanner 2 and the top plate 4 on which the subject is placed based on the past camera image in which the scan position is set.

(Step S710)
In S710, the system control device 72 controls the scanner 2 based on the scan plan set in S709, and the scanner 2 performs scan photographing. The image processing device 73 reconstructs the tomographic image (S710) and ends. The display device 8 displays a tomographic image. The reconstructed tomographic image is stored in the storage device 71.

  Although the gantry type X-ray CT apparatus has been described above, a C-arm type X-ray CT apparatus may be used.

  According to the present embodiment, the position of the MPR image of the subject and the current camera image can be matched. The operator can grasp the form in the body and set the scan plan by using the MPR image whose position is aligned with the current camera image. Further, by diverting the past scan plan, the labor of the operator can be simplified. Further, it is not necessary to perform scanogram imaging of the subject every time an X-ray CT image is acquired. Therefore, the X-ray exposure amount of the subject is reduced.

<Third embodiment>
The third embodiment uses a current scanogram image (current scanogram image) of a subject instead of the current camera image in the first embodiment. Next, processing according to the present embodiment will be described with reference to FIG. FIG. 8 is a flowchart showing the flow of processing.

(Step S801)
In S801, it is determined whether or not a scanogram image (past scanogram image) generated in the past exists in the storage device 71 (S801). If there is no past scanogram image (first scan shooting), the process proceeds to S802. If there is a past scanogram image (the next scan and subsequent scans), the process proceeds to S804.

(Step S802)
In S802, as in S2, the operator sets three reference points on the subject and installs reference markers (S802).

(Step S803)
In S803, as in S3, the scanner 2 scanograms the subject whose reference point is indicated by the reference marker, and the image processing device 73 generates a scanogram image (past scanogram image) (S803). Note that the scanogram image (past scanogram image) in this step is generated in the past than when the scanogram image was captured in S805 described later. The past scanogram image is stored in the storage device 71.

(Step S804)
In S804, the operator resets the reference point on the subject's body at the same position as S802 (S804).

(Step S805)
In S805, the scanner 2 scanograms the subject whose reference point is indicated by the reference marker, and the image processing device 25 generates a current scanogram image (current scanogram image) of the subject (S805).

(Step S806)
In S806, the reading unit 7a reads the past scanogram image and the current scanogram image (S806).

(Step S807)
In S807, the alignment unit 7b performs alignment between the past scanogram image and the current scanogram image. The alignment unit 7b aligns the past scanogram image and the current scanogram image based on the reference markers included in both images (S807).

(Step S808)
In S808, the setting unit 7c sets a scan plan (S808). When the operator diverts the past scan plan, the scan imaging of the same part as the past can be performed. The past scan plan is stored in the storage device 71, and the scan plan device 74 can appropriately read the stored past scan plan.

(Step S809)
In step S809, the system control device 72 controls the scanner 2 based on the scan plan set in step S808, and the scanner 2 performs scan shooting. The image processing apparatus 73 reconstructs the tomographic image (S809) and ends. The display device 8 displays a tomographic image.

  Although the gantry type X-ray CT apparatus has been described above, a C-arm type X-ray CT apparatus may be used.

  According to the present embodiment, the past scanogram image and the current scanogram image of the subject can be aligned. Based on the past scanogram image in which the position is aligned with the current scanogram image of the subject, the operator can grasp the form of the subject in the body and set the scan plan. Further, by diverting the past scan plan, the labor of the operator can be simplified.

Overall view of X-ray CT system X-ray CT system block diagram Block diagram of a control program according to the first embodiment A flowchart showing a flow of processing according to the first embodiment. The figure which shows the example of a screen display in each step of the flowchart of FIG. Block diagram of a control program according to the second embodiment A flowchart showing a flow of processing according to the second embodiment. A flowchart showing a flow of processing according to the third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... X-ray CT apparatus, 2 ... Scanner, 3 ... Patient table, 4 ... Top plate, 5 ... Video camera, 6 ... Light, 7 ... Console, 71 ... Memory | storage device, 72 ... System controller, 73 ... Image processing Device: 74 ... Scan planning device, 8 ... Display device, 9 ... Operation device, 10 ... X-ray tube control device, 11 ... X-ray tube, 12 ... Collimator control device, 13 ... Collimator, 14 ... Detector, 15 ... Data Collecting device, 16 ... rotating plate, 17 ... rotating control device, 18 ... rotating plate driving device, 19 ... driving force transmission system, 20 ... subject, 21 ... opening, 22 ... patient table control device, 23 ... patient table top and bottom Moving device, 24 ... Top plate driving device

Claims (4)

An X-ray source that emits X-rays;
An X-ray detector disposed opposite to the X-ray source across the subject, detecting the X-ray and outputting X-ray transmission data;
Rotating means capable of rotating by mounting the X-ray source and the X-ray detector;
Image processing means for reconstructing a tomographic image based on the X-ray transmission data;
Reading means for reading a scanogram image obtained by taking a scanogram of the subject and a camera image obtained by taking the subject with an optical camera;
Alignment means for aligning the scanogram image and the camera image;
Setting means for setting a scan plan based on the aligned scanogram image;
Display means for displaying at least one of the tomographic image, the scanogram image, and the camera image together with the set scan plan;
An X-ray CT apparatus comprising: The reading means reads a past camera image obtained by photographing the subject with an optical camera in the past and a current camera image photographed currently,
The display means displays at least one of the tomographic image, the past camera image, the current camera image, or an arbitrary cross-sectional image together with the set scan plan.
The X-ray CT apparatus according to claim 1. Marker providing means for providing an optical marker that indicates a reference point for alignment in the subject,
The alignment means performs alignment between the scanogram image and the camera image based on a reference marker indicating the reference point included in the scanogram image and the optical marker included in the camera image, or the past Aligning the past camera image and the current camera image based on optical markers respectively included in the camera image and the current camera image;
The X-ray CT apparatus according to claim 2. The reading means reads a past scanogram image obtained by scanning the subject in the past with a scanogram and a current scanogram image obtained by newly scanning the scanogram,
The display means displays at least one of the tomographic image, the past scanogram image, or the current scanogram image together with the set scan plan.
The X-ray CT apparatus according to claim 1.

Images