JP2002191593A - Computed tomography photographing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a computed tomography photographing system for adequately observing the insertion state of a needle or a catheter, or the like, to a subject. SOLUTION: A re-constituting part 32 is provided with a sagittal re-constituting part 32b for re-constituting a sagittal image. Then tomographic images viewed from at least two different directions are displayed on the same screen in real-time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a computer tomography apparatus capable of displaying a tomographic image in real time.

[0002]

2. Description of the Related Art Conventionally, when a percutaneous needle used for a percutaneous needle biopsy for a tumor such as a lung in a body of a subject or a catheter used for a treatment is inserted, X is used as a guide.
A fluoroscope is used. The X-ray fluoroscope is a device that irradiates a subject with X-rays from a predetermined direction to obtain a fluoroscopic image, and can perform display in real time.

However, when inserting a needle, a catheter, or the like using an X-ray fluoroscope, the insertion state of the needle or the like in the direction that matches the fluoroscopic direction of the X-ray fluoroscope is skilled in discrimination. Therefore, in order to avoid this, the insertion direction of the biopsy needle or the like is limited. In addition, there is a problem that a small tumor or the like cannot be distinguished by an X-ray fluoroscope.

[0004] Therefore, by reconstructing and calculating projection data of the subject in multiple directions to obtain a tomographic image of the subject,
A guide method (hereinafter referred to as CT fluoroscopy) using a computer tomography apparatus capable of imaging almost all lesions such as small tumors has been developed. Here, FIG. 19 shows a display example of a fluoroscopic image using this CT fluoroscopy method. FIG. 19 shows a state where the percutaneous needle N has been inserted into the subject.

Conventionally, a screen on which a reconstructed image is displayed
On S, three reconstructed images B₁Or B _ThreeIs represented,
B on left side of screen₁Image, B in center_TwoImage, B on right_Threeimage
Tomographic image (A) of a plane approximately perpendicular to the body axis direction of the subject.
Xial image) is displayed. In addition, shown on each image
Q being₁Is interested in computed tomography equipment
Area, Q_TwoIs the area where the needle should be inserted, such as a tumor or blood type
(Hereinafter referred to as a target).

[0006]

However, when performing a percutaneous needle biopsy or the like under the guide using three axial images using the above-mentioned conventional computed tomography apparatus, the following problems arise. there were. The problem is that it is difficult to determine the insertion state depending on the insertion direction of the needle or the like only from the axial image in which the needle or the catheter is displayed.

Normally, the insertion direction of the needle or the like is not necessarily the direction perpendicular to the axial image, and the length of the needle or the like inserted and the length displayed on the axial image may be different. FIG. 2 is a conceptual diagram showing a part of the subject.
Explanation will be made using 0. Incidentally, bold lines in FIG. 20 shows a needle, double line shows a state of the needle caught on top axial image B _2.

Thus, when the needle is inserted into the subject at a certain angle with respect to the axial image, two points on the needle are
Considering P ₁ and P ₂ , the length of the inserted needle, that is,
Length from P ₁ to P ₂ is found to be shorter in displayed on the screen B _2. Therefore, while observing the image displayed on the axial screen, the operator imagines the correct insertion state based on experience etc. in the head, so that the needle or catheter can be inserted at any angle. Has been known, which has been a great burden on the operator.

In addition to the case where a needle or the like is inserted, there is a great demand for observing a tomographic image in a direction different from an axial or sagittal image in real time, for example, when observing the movement of a heart or the flow of a contrast medium. . Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a computed tomography apparatus capable of accurately observing a state of insertion of a needle, a catheter, or the like into a subject.

[0010]

According to a first aspect of the present invention, there is provided a data acquisition means for acquiring projection data of a predetermined region of a subject, and First reconstruction means for reconstructing a predetermined tomographic image based on the projection data, and a predetermined reconstruction means for the tomographic image reconstructed by the first reconstruction means based on the projection data in parallel with the data acquisition Second reconstruction means for reconstructing a tomographic image having an angle of?, A tomographic image reconstructed by the first reconstruction means in parallel with the data acquisition, and reconstruction by the second reconstruction means Display means for displaying the obtained tomographic image.

[0013] According to a thirteenth aspect of the present invention, there is provided a data collection means for collecting projection data of a predetermined area of a subject,
Image reconstruction means for reconstructing a first tomographic image of a predetermined area and a second tomographic image having a predetermined angle with the first tomographic image based on the projection data; It is characterized by comprising display means for displaying the configured tomographic image, and dial-type angle adjusting means for adjusting the angle of the second image with respect to the first tomographic image. In addition, the invention according to claim 14 is a data collection unit that collects projection data of a predetermined area of the subject, a storage unit that stores a scano image of the subject, and the data collection unit in parallel with the data collection. Image reconstruction means for reconstructing a tomographic image based on projection data, and display means for displaying a tomographic image reconstructed by the image reconstruction means in parallel with the data collection, on a part of the scano image, It is characterized by having.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment according to the present invention will be described in detail with reference to the drawings. FIG.
1 is a system configuration diagram illustrating a schematic configuration of a computer tomography apparatus according to a first embodiment of the present invention. In FIG. 1, a computer tomography apparatus 1 according to a first embodiment
0 denotes a system control unit 11, an operation unit 12, a gantry / couch control unit 13, a couch 15, an X-ray control device 17, a high-voltage generator 19, an X-ray beam source 21, a detector 23, a rotating gantry 25, and data. It has a collection unit 27 and a display unit 33. The computer tomography apparatus 10 emits an X-ray beam while rotating an X-ray beam source 21 around a subject. The operation unit 12 is for inputting necessary information by an operator, such as a mouse and a keyboard.
A slice to be observed (a slice of interest) is selected, a slice thickness is selected, and various parameters such as X-ray conditions, reconstruction conditions, and correction data are input. The system control unit 11 includes a central processing unit (CPU) and controls the X-ray control unit 17, the gantry / bed control unit 13, and the like.
Image reconstruction is performed based on the projection data output from the data collection unit 27. The detailed configuration of the system control unit 11 will be described later. The X-ray controller 17 controls the timing of the high voltage generation by the high voltage generator 19 based on the X-ray beam generation control signal output by the system controller 11. The high voltage generator 19 supplies a high voltage for irradiating the X-ray beam to the X-ray beam source 21 according to a control signal from the X-ray controller 17.

The X-ray beam source 21 emits a fan-shaped X-ray beam having a thickness in the slice direction toward the subject from multiple directions by the high voltage supplied from the high voltage generator 19. On the other hand, the gantry / bed control unit 13 rotates the rotary gantry 25 based on the gantry / bed control signal output from the system control unit 11 and controls the movement of the bed 15. The rotating gantry 25 holds the X-ray beam source 21 and the detector 23. The rotating gantry 25 is rotated by a gantry rotating mechanism (not shown) about a rotation axis passing through an intermediate point between the X-ray beam source 21 and the detector 23. Also,
The detector 23 includes a plurality of detection elements for detecting X-rays arranged in a two-dimensional direction, and detects X-rays emitted from the X-ray beam source 21 and transmitted through the subject.

The data collection unit 27 includes the system control unit 11
And simultaneously collects and outputs projection data of a plurality of slices of the subject based on the data collection control signal output by the.
The display unit 33 displays a plurality of tomographic images of the subject reconstructed by the reconstruction unit 32 and other information on a monitor.

Here, the system control unit 11 will be described in detail with reference to FIG. 2 which is a block diagram. The system control unit 11 has C as a host controller.
A PU 22 is provided, and a control bus 24 and a data bus 26 are connected to the CPU 22.

The CPU 22 has a built-in clock circuit, manages the operation and time of each unit using a clock from the clock circuit, and supplies this clock to each unit in the system control unit 11 as a common clock. I have. The control bus 24 is a bus for mainly transmitting control signals, and is connected to the CPU 22, a preprocessing unit 28, a disk interface (disk I / F) 30, a reconfiguration unit 32, a display memory 34, and a shooting control unit 31. Have been.

The data bus 26 is a bus for mainly transmitting image data.
8, disk I / F 30, reconstruction unit 32, display memory 3
4. The memory 36 is connected. The disk I / F3
0 is connected to a magnetic disk device 38 as a mass storage device.

As for the connection between the inside and the outside of the system control unit 11, the data collection unit 27 is connected to the pre-processing unit 28, the operation unit 12 is connected to the control bus 24, and the X-ray The control unit 17 and the gantry / bed control unit 13 are connected to the display memory 34, and the display unit 33 is connected to the display memory 34. Next, the operation of the computed tomography apparatus having the above configuration will be described with reference to FIGS.

The operator operates the computer tomography apparatus 10
Is activated, information necessary for shooting is input via the operation unit 12. The information necessary for the imaging is not limited to information regarding imaging such as an imaging region, but may include, for example, information regarding the subject (personal information such as the name and gender of the subject). The information input by the operator is selected by the CPU 22 via the control bus 24 according to the type of information, and only information relating to control of each device is input to the imaging control unit 31. In the imaging control unit 31, information on imaging is converted into more specific control signals, and the control of the bed 15 and the rotating gantry 25, and the generation of high voltage are performed via the gantry / bed control unit 13 and the X-ray controller 17, respectively. The control of the device 19 is performed. Here, the input information regarding the subject is stored in a memory (not shown) or the like, and is stored together with the captured image after the imaging is completed.

An X-ray beam source 21 is connected to the high-voltage generator 19.
X-rays are irradiated to the region of interest to Q ₁ subject disposed on the couch 15, X-rays transmitted through the Q ₁ is, is detected by the detector 23. The projection data detected by the detector 23 is transmitted to the pre-processing unit 28 in the system control unit 11 via the data collection unit 27.
Is input to

The input data is subjected to pre-processing such as calibration in a pre-processing unit 28, and is once written as raw data to a memory 36 such as a readable / writable DRAM via a data bus 26, Further, it is read out from here and sent to the reconstruction unit 32. The reconstruction unit 32
The axial reconstruction unit 32a reconstructs an axial image of the subject, and the sagittal reconstruction unit 32b reconstructs a sagittal image. This is “CT fluoroscopy” in which reconstruction is performed in parallel with data collection, as disclosed in, for example, JP-A-7-320273.
The reconstructed tomographic image data is readable and writable DRA
The information is temporarily written into the display memory 34 such as M, and is read out to the display unit 33 from here, and is displayed as a tomographic image. Note that the display unit 33 simultaneously displays the axial image and the sagittal image in real time. The tomographic image data is read from the display memory 34 as required by the operator and stored in the magnetic disk device 38 via the disk I / F 30.

Here, the image displayed on the display unit 33 will be described with reference to FIGS. Note that FIG.
Is a conceptual diagram when the percutaneous needle N is inserted into the subject P,
FIG. 4 shows a screen displayed on the display unit 33. 3, the Z direction is a direction substantially perpendicular to the axial plane of the subject, the X direction is a direction substantially perpendicular to the coronal plane, and the Y direction is a direction substantially perpendicular to the sagittal plane. Also, on the screen S,
Upper three in the area axial image A ₁ to A _3, in the lower region, a sagittal image A ₄ is shown. If you insert a percutaneous needle N to the target Q _2, such as a tumor or blood species indicated ROI Q ₁ by dotted lines, in the conventional example, as shown in FIG. 19, to axial images axial image B ₁ B to ₃ of has been displayed, in the present embodiment, the newly displayed sagittal image a _4.

[0023] The sagittal image A ₄ and the axial image
Setting a region of A ₁ to A ₃ are, for example, obtained in advance the scanogram image as shown in FIG. 5, the axial image and sagittal image setting frame 50 at an arbitrary position of the object on the image Move. The image setting frame 50, as it can set the axial image and sagittal images simultaneously, dotted lines are reconstructed region as a sagittal image A _4, also three hatched region located in the central portion of the dotted lines shows the reconstructed area as each of the axial images a ₁ to a _3. When the image setting frame 50 is set as shown in FIG. 5 (when setting, a part of the frame is dragged and dropped by a mouse or the like), the area within the dotted line indicated by the image setting frame 50 is sagittal. The image is reconstructed in the image reconstruction unit 32b, and the sagittal image A ₄ shown in FIG.
In the axial images A _{1 to} A ₃ , the substantially cylindrical area indicated by oblique lines in the image setting frame 50 is reconstructed in the axial reconstruction unit 32 a. In addition,
In the image setting frame 50, a dotted line portion for setting a sagittal image and a hatched portion for setting an axial image are integrated, so that an axial image and a sagittal image can be set at the same time.

The positional relationship between the axial image and the sagittal image is set so that the sagittal image passes substantially at the center of the axial image. Note that this positional relationship is indicated by a dotted line (a boundary of a cross section) shown on each image in FIG. Note that the positions of the axial image and the sagittal image in the direction perpendicular to the plane of FIG. 5 are set so that the rotation axis of the detector 23 is at the center of the axial image as an initial value. The change can be made by inputting the direction (in the direction toward or away from the paper surface in FIG. 5) from the rotation axis and how much to move.

Here, the projection data used for the axial image and the sagittal image will be described in detail with reference to FIG. Figure 6 is a diagram for example 256 × 256 pieces of detector elements have viewed detector 23 which are arranged vertically and horizontally from the X-ray beam generation source 21 side and the dotted line indicates the target Q _2. Here, with respect to three axial image A ₁ to A _3, for example, a reconstructed using projection data output from the detecting element of column 9 of the central portion of the detector 23 (shown by hatching) Do. In this case, out of the nine rows of detection elements, three rows are used as one set, and signals of a total of three sets are used. That is, an image is reconstructed using the projection data output from the nine columns of detection elements collectively in three columns. Thus, three axial images can be obtained.

On the other hand, with respect to the sagittal image A _4, the projection data output from all columns of the detector elements of the detector 23, performs only image reconstruction portion necessary to sagittal image A ₄ as each row separate data. As described above, when the reconstruction is performed separately for each column, the resolution in the column direction (Z direction) can be particularly improved. In this embodiment, the reconstruction of the sagittal image and the reconstruction of the axial image are performed separately by the sagittal reconstruction unit 32b and the axial reconstruction unit 32a.
A part or all of the image data created in one image reconstruction may be used in the other image reconstruction.

[0027] For example, it is considered to use a part of the image data created when performing reconstruction of axial images A ₁ to A ₃ in the reconstruction of the sagittal image. This will be described with reference to FIGS. FIG. 7 is a side view of the detector 23 as viewed from the side, and FIG. 8 is a flowchart when creating an axial image and a sagittal image. In FIG. 7, when the reconstruction of the axial image and the reconstruction of the sagittal image are separately performed as described above, the projection data output from the respective detectors are separately input to the reconstruction units 32a and 32b. Is done. In the reconstruction in this case, as for the axial image, as described above, three columns of projection data are combined into one set by averaging or the like, and back projection is performed to perform reconstruction. The sagittal image was reconstructed by back-projecting the projection data for each column. That is, the projection data in the hatched area is used separately in each reconstruction.

On the other hand, in the case of using a part of the image data created when performing reconstruction of axial images to reconstruct the sagittal image, with respect to the projection data in the region of A ₁ to A ₃ shown in FIG. 7 First, the projection data is back-projected separately for each column. (Step 8 in FIG. 8)
1) In parallel with this, the projection data of the area indicated by A ₄ ′ (projection data other than the projection data used in the back projection of the axial image) of the projection data used in the sagittal image is sagittal. Back projection is performed only on pixels necessary for the image.
(Step 84)

As described above, when three projection data are used as one set as described above, one projection data is reconstructed as one set as it is, that is, nine rows of projection data are used. From this, nine axial images will be created.
One axial image is added and averaged for each pixel to form one axial image. That is, three axial images are created from the nine axial images (step 82), and the created axial images are displayed. (Step 83) For the sagittal image, the image data in the area A ₄ ′ is already back-projected in step 84, and for the area other than A ₄ ′, it is necessary in step 81 in the axial image back projection. Complete image data.

That is, regarding the sagittal image, the image data used for each area (except for A ₄ ′ and A ₄ ′) is different, and the image data is arranged for each area to create a sagittal image (step 85). Display the created sagittal image. (Step 86) Thereby, compared with the case where the axial and sagittal images are separately reconstructed, the calculation of the back projection and the like is reduced, and the load on the reconstructing unit can be reduced.

Further, if the number of columns used in the axial image and the sagittal image is the same, for example, if the image is reconstructed as a set of three columns not only in the axial image but also in the sagittal image, 3 The reconstruction can be performed after the projection data of the columns are combined into one set, so that the averaging process in step 81 is not required, and the load on the reconstruction unit can be further reduced. . In the above example, a part of the axial image is used for reconstructing the sagittal image. However, a part of the sagittal image may be used as the axial image. The number of detection elements is not particularly limited, and even when a one-dimensional detector is used, a three-dimensional area of the subject can be imaged by performing a helical scan or the like. Adaptation is possible.

Further, the region of the subject represented by the sagittal image (the dotted line portion of the image setting frame 50 in FIG. 5) is changed to the region of the subject represented by the axial image (FIG. 5).
In may be a narrower region than the hatched portion) of the image setting frame 50, for example, it may be set to perform the reconstruction of the sagittal image A ₄ only the area represented by the axial images A ₂ and A _3. As described above, in the present embodiment, by displaying a sagittal image in real time in addition to the axial image of the subject, the operator can smoothly diagnose when inserting the percutaneous needle or the like into the subject. It is possible to do.

Although an axial image and a sagittal image have been described as two different tomographic images, the direction is limited as long as there are a plurality of tomographic images viewed from different directions. Instead, for example, a combination of an axial image and an oblique image is also conceivable. Next, a first modification of the first embodiment according to the present invention will be described. The first modification differs from the first embodiment in that a sagittal image and an axial image can be set separately. In this modification, the display unit 33
The sagittal image displayed by will be described with reference to FIG.
The image shown in FIG. 9 is a scano image acquired in advance similarly to FIG. 5, and a sagittal image setting frame 51 and an axial image setting frame 5 are displayed on the scano image.
2 is displayed.

The operator sets the respective image setting frames 5
1 and 52 are set at predetermined positions, respectively. The setting is performed using a mouse or the like as in the first embodiment. Each area in the set frame is reconstructed by the axial reconstruction unit 32a and the sagittal reconstruction unit 32b, and is displayed as shown in FIG. 4 as in the first embodiment.

The positional relationship between the axial image and the sagittal image is not limited to the direction parallel to the plane of FIG.
It can also be set separately in the direction perpendicular to the paper. Further, each frame described above can be scaled up and down. That is, when observing a wide area of the subject with a sagittal image and observing a fine portion with an axial image, it is preferable to widen the sagittal setting frame 51 with a mouse or the like and narrow the axial setting frame 52. Note that the maximum size that can be expanded may be determined in consideration of the calculation capabilities of the reconfiguration units 32a and 32b that perform the respective reconfigurations.

Further, on the screen, in addition to the sagittal image A _4, it may be displayed across scanogram. in this case,
A screen as shown in FIG. 10 is displayed. That is, real-time reconstruction is performed only in the sagittal image setting frame 51 specified on the scano image, and the other portions are displayed as scanano images previously stored in a memory or the like (not shown) in order to grasp the entirety. Will be.

As described above, when the area outside the sagittal image setting frame 51 is displayed as a scano image, even when the area inside the sagittal image setting frame 51 is displayed in real time, a wider range of the subject can be obtained. Can be observed. The image setting frames 51 and 52 may be changed at any time on the scano image.

Further, as for the images other than the sagittal images, the images shown in FIG. 4 are displayed as in the first embodiment. Next, a second modification of the first embodiment according to the present invention will be described. Second modification, the area where the image A ₄ in FIG. 4 is displayed, in which the cross-sectional image having an arbitrary angle (oblique image) is displayed. In addition,
The axial image at this point may be a still image.

[0039] As a method for setting the cross-sectional image at an arbitrary angle, first, with the axial images A ₁ to A ₃ is displayed, and inputs an instruction to set an arbitrary cross section from the operation unit 12. When the instruction is input, FIG on axial images A ₂ 11
Are displayed as shown in FIG. The operator sets the center point of the point 41a to a required point of the cross-sectional image to be displayed. In this modification, in particular shows the case of the combined point 41a to the target Q _2.

After the point 41a is set, the section angle is set next. In the present modification, the setting of the cross-sectional angle is to set a cross-section of a plane at an arbitrary angle among the planes perpendicular to the axial image, so that 36
This is performed using a line 42a that can be rotated 0 degrees. This state is shown in FIG. The operator sets an arbitrary cross-sectional angle using the operation unit 12 while observing FIG. Here, for example, assuming that the position of the point is (X ₁ , Y ₁ ) on the axial image and the cross-sectional angle is a, the line 42 a on this axial image is represented by the formula y = ax + Y ₁ -aX _1. It can be seen that an arbitrary cross section can be set.

This will be described with reference to FIG. 13 which is a flowchart showing the operation of the system control unit 11. In the system control unit 11, first, as in the conventional case, in step 120, under the control of the CPU 22,
An axial image of the subject is displayed on the display unit 33.

Next, in step 121, the operator inputs an instruction to display an image other than the axial image from the operation unit 12 only when the image is displayed in this state. This signal is recognized by the CPU 22, and the point 41 a is displayed on the axial image displayed on the display unit 33 in step 122.

When the operator sets the point 41a at an arbitrary position, the position of the point is recognized by the CPU 22 at step 123, and a line 42a passing through the point is displayed on the display unit 33. Further, when the operator determines the line 42a, an angle is obtained from the line 42a (step 124), and a cross section of the angle is displayed on the display unit 33. (Step 125)

In addition to such a method of setting the cross-sectional angle, as shown in FIG. 14, setting may be made using two points 41b and 41c. This method
In this method, two points 41b and 41c are set at different positions in the axial image. After setting each of the two points, a line 42 connecting the points is set.
b is automatically set as shown in FIG. Also in this case, the line 42b can be obtained from the coordinates of the two points. In this case, the angle of the line 42b can be arbitrarily changed by moving at least one of the two points. The above is the operation at the time of setting the cross section. The operation unit 12 used for this operation may be a mouse, a keyboard, or the like.

As this input device, for example, as shown in FIGS. 16 and 17, a dial type device which operates by rotating a predetermined portion with respect to a plane parallel to the surface of the device can be considered. It is provided on a part of the display unit 33 and the like. FIG. 16 is a front view of the input device, and FIG. 17 is a side sectional view. Here, the input device 43 will be described with reference to FIG. 16. The input device 43 has a substantially columnar dial 44 at the center, and the dial 44 is parallel to the paper surface in a substantially circular operation frame 45. It can move freely in direction A (an example is indicated by solid arrows). Further, the dial 44 is rotatable in a circumferential direction about a substantially central portion, and can also be moved in a direction perpendicular to the paper surface. The circumferential direction is indicated by a dotted arrow C, and the direction perpendicular to the paper is indicated by a solid arrow B in FIG. The dial 44 further has a substantially rectangular parallelepiped convex portion 46 at the center thereof, and the convex portion 46 is integrated with the dial 44.

A donut-shaped ring 51 is fitted on the dial 44 at a substantially central portion of a column along the circumference of the dial 44. This ring 51 is a dial 4
4 and the direction A and the direction B, but in the direction C, only the dial 44 rotates, and the ring 51 does not rotate due to the frictional force with the elastic ring 50 described later.

On the other hand, a groove is provided on the inner side of the operating frame 45 (downward in FIG. 17) so that the ring 51 can move in the directions A and B. It is structured so that it is not deviated from this groove by being pressed from the groove. To remove the ring 51 to the outside, by removing the screw 52, the operating frame 45 is detached, and there is no one that presses the ring 51 from above, so that the ring 51 can be removed for repair or the like. An elastic ring 50 having an L-shaped side cross section and made of an elastic body such as rubber is provided on the inner side of the ring 51, and the elastic force causes the ring 51 to move to the state shown in FIG. (Referred to as a steady state).

The dial 44 is provided on its side surface with a 47a for detecting the rotating state of the dial 44 in the direction C, and operates in pairs with the 47b provided on the side surface of the operating frame 45. It is. The rotation detecting means 47 includes, for example, an LED 47 provided on the circumference of the dial 44 and an LED 47a serving as an LED and a light receiving element 47b serving as a light receiving element.
a emits light, and its rotation is detected by receiving the light with light receiving elements 47b provided at appropriate intervals on the circumference of the operating frame 45. Here, the rotation detecting means 47 may be any means as long as the rotation can be detected.

Similarly, on the side surface of the ring 51, there is provided a 48a for detecting the state of movement of the dial 44 in the direction A, and 47b provided on the lower side surface of the operating frame 45.
It works in pairs. Further, a lower portion of the dial 44 is provided with a 49a for detecting a moving state of the dial 44 in the direction B, and operates in a pair with a 47b provided at the bottom of the input device 43.

The operator grips the convex portion 46 provided on the dial 44 and moves the dial 44 in the direction A, for example, based on the image shown in FIG. The point 41a is moved to an arbitrary position. After the position of the point 41a reaches an appropriate position on the axial image, the dial 44 is pressed in the B direction. The pressing in the B direction has the same effect as a so-called click when using a mouse.
The position of a is determined. When the operator stops pressing the dial 44, the elastic ring 50 automatically returns to the steady state. When the operator wants to release the determined position of the point 41a, the dial 44 is moved in the direction B. It is preferable to press twice (so-called double click) within a predetermined time.

Next, when setting the angle of the cross section in FIG. 11, the operator holds the convex portion 46 while holding the convex portion 46.
Is rotated in the C direction, thereby rotating the line 42a interlocked with the rotational motion to an arbitrary angle. Note that the angle of the line 42a matches the inclination angle of the convex portion 46. After the angle of the line 42a becomes an appropriate angle on the axial image, the dial 44 is pressed in the B direction in a manner similar to the setting of the point, and the angle of the line 42a is determined.

The details of the input device 43 have been described above. However, the present invention is not particularly limited to the above-described shape as long as it performs dial-type angle adjustment. In addition, in this modification, in addition to the axial image, a cross-sectional image at an arbitrary angle can be displayed in real time in accordance with an instruction from the operator. Setting is possible.

Note that the input device 4 is used for setting the section angle.
By using 3, the operator can set while holding the convex portion 46, and the operability is further improved. The input device 43 is not limited to CT fluoroscopy, and can be used as long as it sets a tomographic image at another angle on one tomographic image. Further, in the present modification, the image located at the center (the A2 image in FIG. 4) of the three axial images is used as the image for setting the cross section (the image on which points and lines are displayed). may be used as the axial images a ₀ or a _3, it may be provided another axial image for plane setting in addition to the above three axial image a ₁ to a _3.

In this case, for example, the display unit 33 includes
A screen such as 8 is displayed. In FIG. 18, six images are displayed in two rows and three columns, C1 to C3 for observing an axial image are displayed side by side in an upper row, and a C4 image for section setting is displayed in a lower row from the left side, The set cross section is displayed
A C5 image and a C6 image representing information indicating the state of scanning, for example, information indicating that fluoroscopy is being performed, are displayed. In addition, when an axial image for section setting is provided in addition to the axial image for observation (C1 to C3), points are placed on the upper three axial images (C1 to C3) and the set sectional image (C5). , Line, etc. are not displayed, the operator can view the axial image and the image of the set cross section without worrying about the display for setting the cross section, and more concentratedly insert the percutaneous needle N. Can be observed.

In this modification, as a method of setting a cross-sectional angle, an example in which one point is set and then the angle of a line passing through the point is set, and two points are set one by one However, the setting of the section angle is not limited to the above method. In the above-described embodiment and the modified example, the description has been given of displaying an axial image and an image on a plane orthogonal to the axial image. However, the direction of the image is not particularly limited, and a cross section from at least two directions can be displayed. It is also possible to display a cross section shown on a curve on an axial image, that is, a curved surface. In this case, determine three or more points on the axial image,
The curved surface may be obtained by connecting or approximating this, or the cross section can be set by inputting the curved surface equation directly from the input device.

If the cross section of a curved surface can be set, for example,
When inserting a non-linear insert such as a catheter into a subject, the inserted surface of the insert can be accurately displayed by setting the displayed curved surface according to the degree of bending of the insert. Can and is very effective. Although the axial image and the image on the plane orthogonal thereto are displayed simultaneously on the same screen, they may be switched and displayed according to the amount of calculation such as reconstruction. That is, the configuration may be such that an axial image can be switched to an image on a plane orthogonal to the axial image as needed.

Further, a combination of the modified examples is also possible. For example, it is also possible to restrict the region of the subject displayed as an image to a small area as in the first modification, and to set an arbitrary cross-sectional angle as in the second modification. Further, in the above-described embodiment, the X-ray CT apparatus by X-ray irradiation from the X-ray tube has been described.
T or the like.

[0058]

As described above in detail, according to the present invention, when displaying tomographic images viewed from at least two different directions on the same screen in real time, the area of the subject to be reconstructed is limited. Alternatively, by displaying a cross section at an arbitrary angle, it is possible to accurately observe the state of insertion of a needle, a catheter, or the like into the subject.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing a schematic configuration of a computer tomography apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a system control unit according to the first embodiment of the present invention.

FIG. 3 is a conceptual diagram illustrating insertion of a percutaneous needle according to the first embodiment of the present invention.

FIG. 4 is a screen displayed on a display unit according to the first embodiment of the present invention.

FIG. 5 is a scanogram according to the first embodiment of the present invention.

FIG. 6 is a top view of the detector according to the first embodiment of the present invention.

FIG. 7 is a side view of the detector according to the first embodiment of the present invention.

FIG. 8 is a flowchart illustrating an operation of a system control unit according to the first embodiment of the present invention.

FIG. 9 is a scanogram in a first modified example of the first embodiment according to the present invention.

FIG. 10 is a screen displayed on the display unit according to the first embodiment of the present invention.

FIG. 11 is a partial view showing an axial image of a screen displayed on a display unit in a second modification of the first embodiment according to the present invention.

FIG. 12 is a partial view showing an axial image of a screen displayed on a display unit according to a second modification of the first embodiment of the present invention.

FIG. 13 is a flowchart illustrating an operation of a system control unit according to a second modification of the first embodiment of the present invention.

FIG. 14 is a partial view showing an axial image of a screen displayed on a display unit in a second modification of the first embodiment according to the present invention.

FIG. 15 is a partial view showing an axial image of a screen displayed on a display unit in a second modification of the first embodiment according to the present invention.

FIG. 16 is a top view of the input device according to the first embodiment of the present invention.

FIG. 17 is a side sectional view of the input device according to the first embodiment of the present invention.

FIG. 18 is a screen displayed on the display unit according to the first embodiment of the present invention.

FIG. 19 is a screen displayed on a display unit in a conventional example.

FIG. 20 is a conceptual diagram showing a part of a subject in a conventional example.

[Explanation of symbols]

 Reference Signs List 11 system control unit 12 operation unit 13 gantry / bed control unit 15 couch 17 X-ray control device 19 high voltage generator 21 X-ray beam generation source 22 CPU 23 detector 24 control bus 25 rotation gantry 26 data bus 27 data collection unit 28 Preprocessing unit 30 Disk interface (disk I / F) 31 Imaging control unit 32 Reconstruction unit 33 Display unit 34 Display memory 36 Memory 38 Magnetic disk device 41a Point 41b Point 41c Point 42a Line 42b Line 43 Input device 44 Dial 45 Operating frame 46 convex part 47 rotation detecting means 48 movement detecting means 49 movement detecting means 50 elastic ring 51 ring N percutaneous needle P subject

Claims (15)

[Claims] A data acquisition unit configured to acquire projection data of a predetermined region of a subject; a first reconstruction unit configured to reconstruct a predetermined tomographic image based on the projection data in parallel with the data acquisition; Second reconstruction means for reconstructing a tomographic image having a predetermined angle with respect to the tomographic image reconstructed by the first reconstruction means based on the projection data in parallel with data acquisition; Display means for displaying a tomographic image reconstructed by the first reconstructing means and a tomographic image reconstructed by the second reconstructing means in parallel with the computer tomography. Shooting equipment. 2. The computer tomography apparatus according to claim 1, wherein said data collection means is a two-dimensional detector in which detection elements are two-dimensionally arranged. 3. The computed tomography apparatus according to claim 1, wherein the first reconstruction unit reconstructs a plurality of tomographic images substantially parallel to the subject. 4. The tomographic image reconstructed by the first reconstruction means is orthogonal to the tomographic image reconstructed by the second reconstruction means. The computer tomography apparatus according to claim 1. 5. The computed tomography apparatus according to claim 4, wherein the tomographic image reconstructed by the first reconstruction means is an axial image of the subject. 6. The image processing apparatus according to claim 1, wherein the second reconstructing unit reconstructs the image using at least a part of the image data created by the first reconstructing unit. The computed tomography apparatus according to claim 1. 7. The display means for displaying an image representing a positional relationship between a tomographic image reconstructed by the first reconstruction means and a tomographic image reconstructed by the second reconstruction means. The computer tomography apparatus according to claim 1, wherein: 8. The tomographic image representing the positional relationship is a tomographic image reconstructed by the first reconstructing means, and the tomographic image reconstructed by the first reconstructing means includes:
8. The computed tomography apparatus according to claim 7, wherein means for indicating a position of the tomographic image reconstructed by the second reconstruction means is displayed. 9. The image representing the positional relationship is a scano image of a subject, and means for indicating a position of a tomographic image reconstructed by the first and second reconstruction means on the scano image. The computer tomography apparatus according to claim 7, wherein the apparatus is displayed. 10. The computed tomography apparatus according to claim 9, wherein the means for indicating the position of the tomographic image can set the position of the tomographic image reconstructed by the first and second reconstruction means. . 11. The computed tomography according to claim 10, wherein the means for indicating the position of the tomographic image can simultaneously set the position of the tomographic image reconstructed by the first and second reconstruction means. apparatus. 12. The computed tomography according to claim 10, wherein the means for indicating the position of the tomographic image can set the position of the tomographic image reconstructed by the first and second reconstruction means, respectively. apparatus. 13. The computed tomography apparatus according to claim 1, wherein said second reconstruction means reconstructs a curved tomographic image. 14. A data collection means for collecting projection data of a predetermined area of the subject, and a first tomographic image of a predetermined area and a first tomographic image having a predetermined angle with the first tomographic image based on the projection data. Image reconstruction means for reconstructing the second tomographic image, display means for displaying the tomographic image reconstructed by the image reconstructing means, and adjusting an angle of the second image with respect to the first tomographic image. And a dial-type angle adjusting means. 15. A data collection means for collecting projection data of a predetermined area of a subject, a storage means for storing a scano image of the subject, and a tomographic image based on the projection data in parallel with the data collection. Image reconstruction means for reconstructing, and display means for displaying, on a part of the scano image, a tomographic image reconstructed by the image reconstruction means in parallel with the data acquisition, Computer tomography equipment.