JP2002112996A - Medical diagnostic system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medical diagnostic system capable of correcting a photographing region on the way of photographing after the photographing is started according to the photographing region of a set object to be photographed for its medical image. SOLUTION: This medical diagnostic system comprises a photographing region resetter 25 for resetting the photographing region on a screen of a monitor 22 by temporarily interrupting the photographing when a photographing interruption command is received after the photographing is started, and a photographing continuing unit 26 for photographing an unphotographed region of the reset photographing region. Thus, the photographing region can be corrected even on the way of photographing. When it is discovered on the way of photographing that the initially set photographing region is inconvenient, the photographing is not restarted from the start for all the photographing by taking a time, but the photographing region is corrected on the way of the photographing, and the unphotographing region is photographed. Thus, an extension of the photographing time due to double photographing can be avoided, and an excess X-ray exposure to a subject M can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray CT apparatus (X-ray computed tomography apparatus) and an MRI apparatus (X-ray computed tomography apparatus) which use a positioning image to set an imaging area of a subject to be imaged as a medical image. The present invention relates to a medical diagnostic apparatus such as a magnetic resonance tomography apparatus, and more particularly, to a technique that enables correction of an imaging area after starting imaging according to a set imaging area of a medical image imaging target.

[0002]

2. Description of the Related Art In recent years, a general-purpose medical diagnostic apparatus, X
As shown in FIG. 9, the X-ray CT apparatus includes an X-ray tube 51 that irradiates an X-ray fan beam FB to a subject (patient) M and an X-ray in which a number of X-ray detection elements 52a are arranged in a line. An X-ray imaging mechanism 53 is provided so that the detector 52 is opposed to the subject M across the subject M. The X-ray CT apparatus first performs preliminary imaging using the X-ray imaging mechanism 53 to obtain a transmission X-ray image as a positioning image, and then sets an imaging area on the obtained transmission X-ray image. Then, using the X-ray imaging mechanism 53 again, actual X-ray tomography for the set imaging region is executed.

In a conventional X-ray CT apparatus, in preliminary imaging for obtaining a transmission X-ray image, an X-ray tube 51 and an X-ray detector 52 are used.
Is stopped in the state shown in FIG. 9 and the like, and while moving the top plate 54 on which the subject M is placed in the direction of the body axis Z of the subject M (a direction perpendicular to the paper surface), X At the same time that the X-ray fan beam FB is emitted from the X-ray tube 51, the X-ray detection data output from the X-ray detector 52 is collected in association with the movement of the top board 54 to obtain a transmitted X-ray image of the subject M. The transmission X-ray image thus obtained is, as shown in FIG.
The image is displayed on the screen of the monitor 55 as the positioning image PA. The surgeon (operator) performs an input operation with a mouse (not shown) or a console (not shown), and a box cursor 56 surrounds a desired area on the screen of the monitor 55.
The photographing area MR is set by adjusting the position and the size of the image. Of course, the entire region inside the box cursor 56 is the imaging region MR.
Is set as

In actual X-ray CT imaging, the top plate 54 on which the subject M is placed is moved in the direction of the body axis Z of the subject M (a direction perpendicular to the paper surface), and the X-ray tube 51 and the X-ray The detector 52 is rotated around the body axis Z of the subject M. At the same time that the subject M is irradiated with the X-ray fan beam FB from the X-ray tube 51, X-ray detection data output from the X-ray detector 52 is collected as X-ray CT image creation data of each slice surface of the subject M. To go. Image reconstruction is performed based on the X-ray detection data collected in this way, and finally an X-ray CT image is created. The created X-ray CT image is provided for a doctor's diagnosis.

[0005]

However, the above-mentioned conventional X-ray CT apparatus has the following problems. In other words, there is a problem that once a shooting area of a medical image shooting target is set and shooting is once started in accordance with the set shooting area, the shooting area cannot be corrected halfway.

[0006] For example, if it is found in the course of imaging that the initially set imaging area cannot cover the required range, or that the subject M has moved and the imaging area has shifted during imaging, the imaging is stopped. Even if continued, an appropriate X-ray CT image cannot be obtained. However, in the conventional apparatus, once the imaging is started, the imaging area cannot be corrected in the middle, and the imaging must be stopped and all the operations must be performed again from the beginning, so that the imaging time is greatly lengthened. In the case of the X-ray CT apparatus, since the imaging is restarted from the beginning, if the imaging is performed before the stop, the X-ray fan beam is irradiated again, and the subject M is exposed to extra X-rays. The inconvenience of doing so also occurs.

In view of the above circumstances, it is an object of the present invention to provide a medical diagnostic apparatus capable of correcting an imaging region in the middle after starting imaging once in accordance with a set imaging region of a medical image imaging target.

[0008]

According to a first aspect of the present invention, there is provided a medical diagnostic apparatus for imaging a positioning image for setting an imaging area of a medical image imaging target in a subject. Positioning image capturing means, image display means for displaying a positioning image on a screen, shooting area setting means for setting a shooting area on the screen of the image display means, and a shooting area set by the shooting area setting means In a medical diagnostic apparatus including a medical image capturing unit that obtains medical image creation data by capturing an image, when an imaging stop instruction is received after the medical image capturing unit starts capturing an image, the image capturing is temporarily stopped to perform medical image capturing. A shooting area resetting means for resetting a target shooting area on the screen of the image display means, and an imaging continuation means for shooting an unphotographed area in the reset shooting area It is equipped with a.

According to a second aspect of the present invention, in the medical diagnostic apparatus according to the first aspect, the positioning image capturing means is configured to output an X-ray output from an X-ray detector with X-ray irradiation by an X-ray tube. The medical image capturing means is configured to obtain a transmission X-ray image as a positioning image based on the X-ray detection data based on the X-ray detection data output from the X-ray detector along with X-ray irradiation by the X-ray tube. An X-ray CT image is created by performing image reconstruction processing based on the image processing.

[Operation] Next, the operation of the medical diagnostic apparatus according to the present invention will be described. According to the medical diagnostic apparatus of the first aspect, the positioning image capturing means captures a positioning image for setting a capturing area of a medical image capturing target in the subject. The image display means immediately displays the positioning image on the screen. The imaging region setting means sets an imaging region of the subject on the screen according to an instruction from the operator. Then, imaging by the medical image imaging means is started according to the set imaging region, and medical image creation data is collected.

However, the initially set imaging region is inconvenient (for example, the required range cannot be covered, or the subject moves during the imaging, and the imaging region shifts). In the case where it is known in the middle of the imaging, the imaging region resetting means, upon receiving the imaging interruption instruction from the operator, temporarily suspends the imaging and displays the imaging region of the medical image imaging target according to the instruction from the operator. Reset on the screen of the means. Once the shooting area has been reset,
The imaging continuation unit restarts the imaging, captures an image of an unphotographed area in the reset imaging area, and collects remaining medical image creation data.

As described above, in the medical diagnostic apparatus according to the present invention, the resetting of the imaging region of the medical image imaging target by the imaging region resetting unit can be performed after the imaging is once started. In the restarted imaging, imaging is performed on an unphotographed area in the imaging area, and an already captured area in which medical image creation data has already been collected before the imaging is temporarily stopped is not imaged again. As a result, if it is found during the imaging that the initially set imaging area is inconvenient after the imaging is started, there is no need to take all the time to restart the imaging from the beginning, and the imaging area is corrected during the imaging. To take an image of the unphotographed area,
The extension of the photographing time due to the double imaging is avoided.

In the case of the medical diagnostic apparatus according to the second aspect of the present invention, the medical diagnostic apparatus is configured as an X-ray CT apparatus. A transmission X-ray image is obtained as a positioning image based on the output X-ray detection data. The medical image capturing means,
The image reconstruction processing is performed based on the X-ray detection data output from the X-ray detector accompanying the X-ray irradiation by the X-ray tube, and X
A line CT image (X-ray computed tomographic image) is created.
Therefore, in the imaging that is resumed after the reset of the imaging region and is continued, since the already-photographed region is not imaged again, unnecessary X-ray exposure to the subject can be eliminated.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an X-ray C according to the embodiment.
It is a block diagram which shows the whole structure of T apparatus.

In the X-ray CT apparatus according to the embodiment, as shown in FIG. 1, an X-ray tube 1 for irradiating an object M with an X-ray fan beam FB and a number of X-ray detecting elements 2a are arranged in a line. The X-ray imaging mechanism 3 in which the X-ray detector 2 is opposed to the subject M across the subject M, and the body of the subject M while maintaining the X-ray tube 1 and the X-ray detector 2 facing each other. An imaging mechanism rotation drive unit 4 that rotates around the axis Z, a top plate 5 that can reciprocate in the direction of the body axis Z of the subject M (a direction perpendicular to the paper surface) while the subject M is mounted, and the like. I have. This X-ray CT apparatus uses an X-ray imaging mechanism 3 to generate an X-ray CT image (medical image).
A transmission X-ray image as a positioning image for determining an imaging region of an imaging target can be captured, and an X-ray CT image used for diagnosis can be finally captured using the X-ray imaging mechanism 3. It has a configuration. Hereinafter, the configuration of each part of the embodiment device will be specifically described.

As shown in FIG. 1, the imaging mechanism rotation drive unit 4 is configured to rotate the rotation ring 9 as the rotation force of the motor 6 is transmitted via the pulley 7 and the belt 8. I have. The X-ray tube 1 and the X-ray detector 2 of the X-ray imaging mechanism 3 are fixed to a rotating ring 9, and the X-ray tube is rotated as the rotating ring 9 rotates in conjunction with the forward or reverse rotation of the motor 6. 1 and the X-ray detector 2 rotate around the body axis Z of the subject M. Note that the imaging mechanism rotation drive unit 4 is configured to execute a necessary rotation drive operation under the control of the imaging mechanism control unit 10.

The irradiation control unit 11 includes a photographing control unit 16
The tube voltage, tube current, etc. of the high voltage generator (not shown) of the X-ray tube 1 are controlled in accordance with the set irradiation conditions from. X-ray tube 1
The X-ray detection data output from the X-ray detector 2 accompanying the irradiation of the X-ray fan beam FB from the
AS) 13.

Further, the top 5 is configured to be reciprocated in the direction of the body axis Z of the subject M under the control of the top driving unit 12. The imaging mechanism control unit 10
The control of the illumination control unit 11 or the top plate driving unit 12 is executed in accordance with an input operation from the console 14 or the mouse 15 or a command signal transmitted from the imaging control unit 16 in a timely manner according to the imaging progress.

On the other hand, in the X-ray CT apparatus of the embodiment, a data processing unit 17 for processing the X-ray detection data output from the X-ray detector 2 is provided at a stage subsequent to the data collection unit 13. The data processing unit 17 includes a transmission image memory 18 that stores a transmission X-ray image as a positioning image for setting an imaging region in the subject M.

In the case of preliminary imaging for capturing an image for positioning, while the X-ray tube 1 and the X-ray detector 2 are stopped in the state shown in FIG. The X-ray tube 1 emits an X-ray fan beam FB while moving in the direction of the body axis Z of M, and at the same time, associates the X-ray detection data output from the X-ray detector 2 with the moving position of the top 5. The transmission X-ray image is stored in the transmission image memory 18 as a positioning image. In other words, the positioning image is obtained by relatively horizontally scanning the X-ray imaging mechanism 3 in the direction of the body axis Z of the subject M.

On the other hand, the data processing section 17 has a detection data memory 19 for storing X-ray detection data as X-ray CT image creation data, and an image based on the X-ray detection data stored in the detection data memory 19. An image reconstruction unit 20 for performing reconstruction processing, and a CT tomographic image memory 21 for storing an X-ray CT image finally created are provided.

In the case of actual imaging for obtaining X-ray CT image creation data, the top plate 5 on which the subject M is mounted is moved to the body axis Z of the subject M.
X-ray tube 1 and X-ray detector 2
Is irradiated with the X-ray fan beam FB to the subject M by the X-ray tube 1 while rotating about the body axis Z of the subject M, and at the same time, the X-rays of each slice plane of the subject M output from the X-ray detector 2 are output. The line detection data is collected as X-ray CT image creation data and stored in the detection data memory 19. That is, X-ray CT image creation data is obtained by relatively rotating and scanning the X-ray imaging mechanism 3 in the direction around the body axis Z of the subject M.

Further, a monitor 22 is provided downstream of the data processing section 17. The monitor 22 displays a positioning image, an X-ray CT image, or the like on a screen according to a command or the like from the imaging control unit 16. The monitor 22 corresponds to an image display unit in the present invention.

The X-ray CT apparatus of the embodiment is shown in FIG.
As shown in FIG. 2, a photographing area setting unit 23 for setting a photographing area on the screen of the monitor 22 on which the positioning image PA is projected is provided. The photographing area setting unit 23 corresponds to a photographing area setting unit in the present invention. That is, when setting an imaging region of an X-ray CT image imaging target, the imaging region setting unit 23 displays the positioning image P on the screen of the monitor 22.
A and a box cursor 24 indicating a shooting area are displayed in a superimposed manner. The operator performs an input operation on the console 14 or the mouse 15, and enlarges the box cursor 24 as shown by a dashed line, shrinks it as shown by a dashed line, and further moves the position of the entire cursor. To set the shooting region MR. Of course, the entire region inside the box cursor 24 is set as the imaging region MR, the upper side 24a of the cursor is a start line (start point), the lower side 24b of the cursor is an end line (end point), and both upper and lower sides 24 of the cursor are set.
Field of view (FOV) is between a and b.

Further, as shown in FIG. 1, the apparatus of the embodiment receives an instruction to interrupt the imaging after the start of the actual X-ray tomography, temporarily suspends the imaging, and resets the imaging region of the medical imaging target. The camera includes an imaging area resetting unit 25 and an imaging continuation unit 26 that takes an image of an unphotographed area in the reset imaging area and takes over the imaging. The photographing area resetting section 25 corresponds to a photographing area resetting section in the present invention, and the imaging continuation section 26 corresponds to an imaging continuation section in the present invention. That is, in the X-ray CT apparatus according to the embodiment, for example, when it is found in the middle of imaging that the initially set imaging area has not been able to cover the required range, the imaging area resetting unit 25 and the imaging Continuation unit 26
Thus, the imaging area can be corrected during the imaging.

When the imaging region is to be corrected during the actual X-ray tomographic imaging after the start of the imaging, an input operation (imaging interruption instruction) for starting the correction of the imaging region is performed by the console 14 or the mouse 15. Immediately, the imaging is suspended, and FIG.
As shown in the figure, the box cursor 24 on the screen of the monitor 22 is the box cursor 2 indicating the photographed area of the photographed area.
4A and a box cursor 24B indicating an unphotographed area of the photography area MR. Although the box cursor 24A cannot be adjusted, the box cursor 24B can be adjusted in size and position in the same manner as the box cursor 24. Note that the above-described temporary suspension of the imaging is performed, for example, at a certain X
When the data acquisition for obtaining the X-ray CT image (slice image) is completed, that is, when the X-ray imaging mechanism 3
The operation is interrupted at the time of one rotation to obtain a T image (slice image).

The operator adjusts the box cursor 24B to reset the shooting area. The reset photographing region Mr is obtained by combining the non-photographing region MRb surrounded by the box cursor 24B with the already photographed region MRa surrounded by the box cursor 24A.

Next, when the operator performs an input operation for completing the resetting of the photographing region using the console 14 or the mouse 15, the photographing is resumed by the photographing continuation unit 26, and the photographing is executed for the unphotographed region MRb indicated by the box cursor 24B. Is done. In other words, the imaging of the re-set imaging region Mr is apparently performed two times with the interruption of the imaging, but the two imagings are performed as one overall.
Image reconstructing unit 20
Is X obtained from the photographed area MRa and the unphotographed area MRb.
Line detection data can be collectively handled as data of one photographing.

Next, the progress process of X-ray tomography by the X-ray CT apparatus of the embodiment having the above-described configuration will be described.
This will be described with reference to the drawings. FIG. 4 is a flowchart showing the progress of X-ray tomography by the apparatus of the embodiment.
Hereinafter, a description will be given from the stage where the subject M is placed on the top 5, the top 5 is moved to set the subject M at the imaging start position, and the preparation for imaging is completed.

[Step S1] While moving the table 5 in the direction of the body axis Z of the subject M with the X-ray tube 1 and the X-ray detector 2 stopped in the state shown in FIG. , X
At the same time that the X-ray fan beam FB is irradiated by the X-ray tube 1, the X-ray detection data output from the X-ray detector 2 is collected in association with the movement of the top 5 to obtain a transmitted X-ray image as a positioning image. .

[Step S2] As shown in FIG. 5, the obtained positioning image PA and the box cursor 24 for setting the photographing area are superimposed on the screen of the monitor 22.

[Step S3] The operator operates the console 1
4 or the mouse 15 to operate the box cursor 2
The size and position of 4 are adjusted to set the imaging region MR. Normally, when setting the imaging region MR, other imaging conditions such as X-ray irradiation conditions are also set.

[Step S4] An operation input for starting imaging for actual X-ray tomography is performed from the console 14 or the mouse 15. While moving the top plate 5 in the direction of the body axis Z of the subject M and rotating the X-ray tube 1 and the X-ray detector 2 around the body axis Z of the subject M, the X-ray tube 1
The X-ray fan beam FB is irradiated to the X-ray detector 2, and at the same time, X-ray detection data of each slice plane in the imaging region MR of the subject M output from the X-ray detector 2 are sequentially collected as X-ray CT image creation data, and the detection data is collected. It is stored in the memory 19.

[Step S5] For example, during imaging, the operator notices that the initially set photographing region MR does not cover the required range, and executes resetting of the photographing region from the console 14 or the mouse 15. Immediately after the command (imaging stop instruction) is input, the imaging is temporarily stopped. Then, as shown in FIG. 6, the box cursor 24 on the screen of the monitor 22 is
4B.

[Step S6] The operator operates the console 1
By operating the mouse 4 or the mouse 15, for example, as shown in FIG.
After Rb is extended downward to set the shooting region MR to the shooting region Mr, the user inputs further the completion of resetting of the shooting region.

[Step S7] The imaging for the actual X-ray tomography is resumed, and only the unphotographed region MRb of the photographed region Mr is photographed to collect data for producing an X-ray CT image. Remember.

[Step S8] Based on the X-ray detection data stored in the detection data memory 19, an image reconstruction process is performed by the image reconstruction unit 20, and finally an X-ray CT image is created. Will be displayed.

[Step S9] When the creation and display of the X-ray CT image are all completed, the X-ray tomography is completed.

As described above, in the case of the X-ray CT apparatus of the embodiment, after the start of imaging, the imaging is temporarily stopped by the imaging region resetting unit 25, and the imaging region MR is changed to the imaging region Mr on the screen of the monitor 22. The non-photographing area MR in the photographing area Mr reset by the imaging continuation unit 26
Since the imaging is performed for b, the imaging area can be corrected even during the imaging, and the imaging area set first does not cover the necessary range, or the subject is not If you find out that the shooting area has shifted due to movement, it is possible to correct the shooting area in the middle of the shooting and capture only the unphotographed area without taking all the time and starting over again. As a result, it is possible to avoid an increase in the imaging time due to the double imaging, and to eliminate unnecessary X-ray exposure to the subject.

The present invention is not limited to the above embodiment, but can be modified as follows. (1) In the case of the embodiment, when the photographing region is reset, both the box cursor 24A indicating the photographed region MRa in the photographing region MR and the box cursor 24B indicating the unphotographed region MRb are displayed on the screen of the monitor 22. However, as shown in FIG. 8, the box cursor 24A indicating the photographed area MRa may not be displayed, and only the box cursor 24B indicating the unphotographed area MRb may be displayed, as shown in FIG.

(2) In the case of the embodiment, the box cursor 24B indicating the unphotographed area MRb is set outside the range of the box cursor 24A indicating the captured area MRa.
This box cursor 24B is moved to the box cursor 24A.
May be set to include a part of In this case, the box cursor 24A in the box cursor 24B
The measurement including the part of the measurement is performed twice.

(3) In the embodiment, the photographing area is set by surrounding the photographing area with the box cursor.
The shooting area may be set by a method other than the box cursor. For example, a configuration in which a shooting area is set by designating and inputting a point at each corner of the shooting area on the screen may be adopted.

(4) The medical diagnostic apparatus of the present invention is not limited to the X-ray CT apparatus as in the embodiment, but is, for example, MR.
The present invention is also applicable to various devices that do not use X-rays, such as an I device.

[0044]

As described in detail above, according to the medical diagnostic apparatus of the first aspect of the present invention, when an imaging stop instruction is received after the start of imaging by the medical image imaging means, the imaging is temporarily interrupted to stop the imaging. Since it is provided with an imaging area resetting means for resetting the target imaging area on the screen of the image display means and an imaging continuation means for imaging an unphotographed area in the reset imaging area, even during the imaging, If it is possible to correct the shooting area and find that the initially set shooting area is inconvenient during the shooting, the shooting area can be corrected during the shooting without taking all the time and starting over again. Can be corrected to capture an image of an unphotographed area, thereby avoiding an increase in the photography time due to double imaging.

According to the medical diagnostic apparatus of the second aspect of the present invention, since the medical diagnostic apparatus is configured as an X-ray CT apparatus, it is possible to obtain an X-ray CT image of an imaging area reset during imaging. In the imaging resumed after the reset of the imaging region, the imaging region is not imaged again, so that unnecessary X-ray exposure to the subject can be eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of an X-ray CT apparatus according to an embodiment.

FIG. 2 is a schematic diagram illustrating a screen of a monitor when a shooting area is set in the embodiment device.

FIG. 3 is a schematic diagram illustrating a screen of a monitor when a shooting area is reset in the apparatus according to the embodiment.

FIG. 4 is a flowchart illustrating a progress process of X-ray tomography performed by the apparatus according to the embodiment.

FIG. 5 is a schematic diagram showing a monitor screen when setting an imaging region in X-ray tomography by the embodiment device.

FIG. 6 is a schematic diagram showing a monitor screen at the start of resetting of an imaging region in X-ray tomography by the embodiment device.

FIG. 7 is a schematic diagram showing a screen of a monitor at the time of completion of resetting of an imaging region in X-ray tomography by the apparatus of the embodiment.

FIG. 8 is a schematic diagram showing a screen of a monitor at the time of resetting a shooting area in the modified device.

FIG. 9 is a schematic diagram showing an X-ray imaging mechanism of a conventional X-ray CT apparatus.

FIG. 10 is a schematic view showing a monitor screen displaying an example of a positioning image of a conventional X-ray CT apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... X-ray tube 2 ... X-ray detector 3 ... X-ray imaging mechanism 17 ... Data processing unit 18 ... Transmission image memory 19 ... Detection data memory 20 ... Image reconstruction unit 21 ... CT tomographic image memory 22 ... Monitor 23 ... Shooting Area setting unit 24 Box cursors 24A and 24B Box cursor 25 Imaging region resetting unit 26 Imaging continuation unit M Subject MR Imaging region Mr Reset imaging region MRb Unimaged region

Continued on the front page F term (reference) 4C093 AA22 CA16 CA18 CA34 EE01 FA13 FA42 FG04 FG13 4C096 AA01 AB37 AB39 AD15 DD08 DD13 5B057 AA09 BA03 BA24 BA26 CA12 CA16 CE10

Claims (2)

[Claims] 1. A positioning image capturing means for capturing a positioning image for setting an imaging region of a medical image capturing target in a subject, an image displaying means for displaying a positioning image on a screen, and the image displaying means A medical diagnostic apparatus comprising: a photographing region setting unit that sets a photographing region on a screen of the medical device; and a medical image capturing unit that captures a photographing region set by the photographing region setting unit and obtains medical image creation data. Receiving an imaging interruption instruction after the start of imaging by the medical image imaging means, temporarily interrupting the imaging and resetting the imaging area of the medical image imaging target on the screen of the image display means; A medical diagnostic apparatus comprising: an imaging continuation unit that performs imaging of an unphotographed area in a set photography area. 2. The medical diagnostic apparatus according to claim 1, wherein the positioning image capturing unit performs transmission X-ray detection based on X-ray detection data output from an X-ray detector accompanying X-ray irradiation by an X-ray tube. The medical image capturing means is configured to obtain an X-ray image as a positioning image.
A medical diagnostic apparatus configured to generate an X-ray CT image by performing image reconstruction processing based on X-ray detection data output from an X-ray detector with irradiation of a ray.