JPH08289888A - Tomography scheduling method and tomograph - Google Patents

Abstract

PURPOSE: To easily set a photographing position and a photographing angle by preliminarily photographing around a vertebral column, setting positions between the respective vertebrae of the vertebral column as the photographing positions by the result of the photographing, recognizing an angle between the respective kinds of the vertebral column as the photographing angles and determining the photographing positions and the photographing angles. CONSTITUTION: At the time of scheduling tomography, preliminary scanning is performed by the tomograph provided with an X-ray tube 50 and a detector 80 so as to recognize the shape of the vertebral column and parts between the vertebrae, detection data are inputted to a data processing part 31 and converted to image data and the positions between the respective kinds are set as the photographing positions. At the time, the photographing position is manually set from an input means 10 while referring to the scout image of a display means 20. Then, each photographing angle is obtained from the scout image obtained by the preliminary scanning. For instance, the inclination of a slice scheduled line passing through the photographing position is determined as the photographing angle. Thereafter, the photographing position and the photographing angle are used and a photographing schedule for the tomography between the vertebrae is made in a photographing schedule part 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tomographic imaging planning method and a tomographic imaging apparatus, and more particularly to a tomographic imaging planning method and tomographic imaging apparatus suitable for preparing an imaging plan such as intervertebral imaging imaging position and angle setting. .

[0002]

2. Description of the Related Art X-ray tomography equipment and MRI (Magnetic R
An esonance imaging device is widely used as a medical diagnostic device capable of performing tomographic imaging of the inside of a subject.

For example, when an X-ray tomography apparatus is used for imaging, various imaging conditions such as scan speed, tube voltage, tube current, slice width, scan pitch, imaging position, and imaging angle are input in advance. Keep it. Then, scanning is performed according to the input imaging conditions to obtain a desired tomographic image.

When performing such tomography, tomography may be performed on the intervertebral space. The spine is slightly curved, which makes the slice angles (imaging angles) slightly different at each position between the vertebrae.

In the conventional intervertebral tomography, slice positions (imaging positions) and slice angles set in the past are used as initial values. Therefore, in the case of the first subject or when the progress of the medical condition changes even in the same subject, there is a problem that proper intervertebral tomography cannot be performed if the past settings are used as they are. are doing.

[0006]

Therefore, when the above problems occur, it is necessary to manually set the imaging position and the imaging angle at which the intervertebral space is tomographically imaged. Therefore, since such manual work is required,
There is a problem that setting of imaging conditions for tomography between the vertebrae is very troublesome.

The present invention has been made in view of the above points, and a first object of the present invention is to facilitate setting of a photographing position and a photographing angle suitable for individual states of a subject at the time of intervertebral tomography. It is to realize a feasible tomography planning method. A second object is to realize a tomography apparatus capable of easily setting an imaging position and an imaging angle suitable for each state of the subject at the time of intervertebral tomography.

[0008]

The inventor of the present application has conducted earnest research to improve the drawbacks of the conventional method and apparatus for performing intervertebral tomography, and as a result, the imaging suitable for intervertebral tomography. The present invention has been completed by finding out a new method of setting the position and the photographing angle, and finding a photographing method and a photographing apparatus capable of quickly setting the position and the photographing angle suitable for such intervertebral tomography. It is a thing.

That is, the present invention as means for solving the problems is as described in the following (1) to (6). (1) A first means for solving the problem is to perform preliminary imaging around the spinal column, and set the position between the vertebrae of the spinal column as the imaging position based on the result of the preliminary imaging. The tomography planning method is characterized in that the angle between the vertebrae of the spinal column is recognized as the imaging angle from the result, and the imaging position and the imaging angle are determined.

In this case, the photographing position is set manually by the operator by referring to the preliminary photographing result, or automatically by pattern recognition or the like by referring to the preliminary photographing result. Either case is acceptable.

Further, the recognition of the photographing angle can be automatically set by pattern recognition or the like with reference to the preliminary photographing result. (2) A second means for solving the problem is position setting means for setting a position between each vertebra of the spinal column to determine an imaging position based on a result of performing preliminary imaging around the spinal column, and a position setting means for surrounding the spinal column. A tomography apparatus, comprising: an angle recognition unit that determines an imaging angle by recognizing an angle between each vertebra of a spinal column based on a result of performing preliminary imaging.

In this case, the setting of the photographing position by the position setting means is performed by the operator manually referring to the result of the preliminary photographing, or automatically by pattern recognition or the like by referring to the result of the preliminary photographing. It does not matter whether it is set manually.

Further, the determination of the photographing angle by the angle recognizing means can be automatically set by pattern recognition or the like with reference to the preliminary photographing result. (3) A third means for solving the problem is area recognition means for recognizing the area of each vertebra of the spine based on the result of preliminary imaging around the spine, and each of the spine recognized by the area recognition means. Position setting means that sets the intermediate position of the opposing faces of the vertebra to determine the imaging position, and the imaging angle is determined by recognizing the angle between each vertebra of the spinal column from the result of performing preliminary imaging around the spinal column. And an angle recognizing means for operating the tomography apparatus.

(4) A fourth means for solving the problem is position setting means for setting the position between the vertebrae of the spinal column based on the result of preliminary imaging around the spinal column to determine the imaging position.
It is sandwiched between the region recognized by the region recognition unit that recognizes the region of the spine around the position set by the position setting unit and the region recognized by the region recognition unit as a result of the preliminary imaging around the spine. A tomography apparatus, comprising: an angle determining unit that determines an imaging angle based on a bisecting angle.

(5) A fifth means for solving the problem is position setting means for setting the position between the vertebrae of the spinal column and determining the imaging position based on the result of preliminary imaging around the spinal column,
A line setting means for setting the center line of the spinal column based on the result of preliminary imaging around the spine and the angle between the vertebrae are recognized from the center line of the spine set by the line setting means to determine the shooting angle. A tomography apparatus comprising: an angle recognizing means for determining.

In this case, the center line of the spinal column is set by the line setting means when the operator manually sets it by referring to the result of the preliminary photographing, and when the operator recognizes the pattern by referring to the result of the preliminary photographing. It does not matter whether it is automatically set by. Further, an angle perpendicular to the center line is suitable as the shooting angle.

(6) A sixth means for solving the problem is a line setting means for setting a center line of the spinal column based on the result of preliminary imaging around the spinal column, and a spinal column set by the line setting means. Position setting means that sets the position between each vertebra from the pixel value on the center line to determine the imaging position, and recognizes the angle between each vertebra of the spinal column from the result of performing preliminary imaging around the spine. And an angle recognizing unit that determines an imaging angle by using the tomographic imaging apparatus.

In this case, the center line of the spinal column is set by the line setting means when the operator manually sets it by referring to the result of the preliminary photographing, and when the operator recognizes the pattern by referring to the result of the preliminary photographing. It does not matter whether it is automatically set by.

Further, the determination of the photographing angle by the angle recognition means can be automatically set by pattern recognition or the like with reference to the preliminary photographing result. Further, the present invention, which is a means for solving the problems, includes the above (1) to
In addition to (6), means described in (7) and (8) below are also included.

(7) A seventh means for solving the problem is that, in the above-mentioned means (6), the center line of the spinal column is obtained from the result of preliminary imaging, and an image of the preliminary imaging result on this center line is obtained. Is a tomography apparatus characterized in that the pixel value of is smoothed to obtain an extreme value, the position between the vertebrae of the spinal column is detected, and the position is set as an imaging position. The smoothing in this case is realized by the filter processing. Further, as the extreme value, a minimum value or a maximum value is selected according to the preliminary imaging result.

(8) The eighth means for solving the problem is the area recognition means for recognizing the area of each vertebra of the spine from the result of preliminary imaging around the spine, and the area recognition means. Position setting means for setting an intermediate position of the facing surface of each vertebra of the spinal column to determine an imaging position, line setting means for setting a central line of the spinal column based on a result of preliminary imaging around the spinal column, and A tomography apparatus comprising: an angle recognizing unit that recognizes an angle between each vertebra from a center line of the spinal column set by the line setting unit and determines an imaging angle.

In this case, the setting of the center line of the spinal column by the line setting means is performed by the operator manually referring to the result of preliminary photographing, or by pattern recognition by referring to the result of preliminary photographing. It does not matter whether it is automatically set by.

Further, the determination of the photographing angle by the angle recognizing means can be automatically set by pattern recognition or the like with reference to the preliminary photographing result.

[0024]

In the tomography planning method which is the first means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed. The position between the vertebrae of the spinal column is set as the imaging position based on the result of this preliminary imaging. Further, the angle between the vertebrae of the spinal column is recognized as the imaging angle from the result of the preliminary imaging. A tomographic imaging plan is drafted based on the imaging position thus set and the recognized imaging angle.

In the tomography apparatus which is the second means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed. The position between the vertebrae of the spinal column is set as the imaging position based on the result of this preliminary imaging. Further, the angle between the vertebrae of the spinal column is recognized as the imaging angle from the result of the preliminary imaging. Tomographic imaging is performed according to the imaging position set in this manner and the recognized imaging angle.

In the tomography apparatus which is the third means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed to obtain the regions of each vertebra of the spinal column. Then, the intermediate position of the facing surface of each vertebra in the recognized region is set as the imaging position. Further, the angle between the vertebrae of the spinal column is recognized as the imaging angle from the result of the preliminary imaging. Tomographic imaging is performed according to the imaging position set in this manner and the recognized imaging angle.

In the tomography apparatus which is the fourth means for solving the problem, first, preliminary imaging of the spinal column is performed. The position between the vertebrae of the spinal column is set as the imaging position based on the result of this preliminary imaging. In addition, the preliminary imaging result around the spine around the set shooting position is referred to, and the region of each vertebra of the spine around the set shooting position is recognized. Then, the photographing angle is determined by the bisector of the angle sandwiched between the recognized regions. Tomographic imaging is performed at the imaging position and imaging angle set in this way.

In the tomography apparatus which is the fifth means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed. The position between the vertebrae of the spinal column is set as the imaging position based on the result of this preliminary imaging. In addition, the center line of the spinal column is set based on the result of preliminary imaging around the spinal column. The angle between the vertebrae is recognized from the center line of the spinal column, for example, the angle perpendicular to the center line is recognized as the photographing angle, and the photographing angle is determined. Tomographic imaging is performed at the imaging position and imaging angle set in this way.

In the tomography apparatus which is the sixth means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed. The center line of the spinal column is set based on the result of this preliminary imaging. Then, the position between the vertebrae is set as the imaging position based on the pixel value on the set center line. Further, the angle between each vertebra of the spinal column is recognized from the result of the preliminary imaging around the spinal column, and the imaging angle is determined. Tomographic imaging is performed at the imaging position and imaging angle set in this way.

In the tomography apparatus which is the seventh means for solving the problem, the detection of the position of each vertebra in the sixth means smooths the pixel value of the image of the preliminary photographing result on the center line of the spinal column. Then, the extreme value is calculated.

In the tomography apparatus which is the eighth means for solving the problem, first, preliminary imaging of the periphery of the spinal column is performed to obtain the regions of each vertebra of the spinal column. Then, the intermediate position of the facing surface of each vertebra in the recognized region is set as the imaging position. In addition, the center line of the spinal column is set based on the result of preliminary imaging around the spinal column. The angle between the vertebrae is recognized from the center line of the spinal column, for example, the angle perpendicular to the center line is recognized as the photographing angle, and the photographing angle is determined. Tomographic imaging is performed at the imaging position and imaging angle set in this way.

[0032]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a flowchart showing the basic processing procedure of the tomography planning method of the present invention. FIG. 2 is a block diagram showing the configuration of the main part of the tomography apparatus used in the tomography planning method of the present invention. And
FIG. 3 is a configuration diagram showing the overall configuration of the tomography apparatus.

<Structure (1) of Tomographic Imaging Apparatus> First, the structure of the tomographic imaging apparatus in the embodiment of the present invention will be described with reference to FIGS.

The tomography apparatus of the present invention can be applied to both an X-ray apparatus and an MRI apparatus, but the X-ray tomography apparatus will be described as an example in the following embodiments. I shall.

The input means 10 is means for receiving various inputs of instructions from the operator, and is composed of a keyboard, various pointing devices and the like. The display means 20 displays not only the finally obtained tomographic image but also various images at an intermediate stage in the imaging plan for obtaining the tomographic image.
It is composed of various display means such as a CRT (Cathode-ray Tube) and a liquid crystal panel.

The control unit 30 determines the photographing position and the photographing angle by referring to the detection data obtained by the preliminary photographing, makes a photographing plan from the photographing position and the photographing angle, and generates the control data for scanning. It is a thing. The control unit 30 is configured by hardware such as a processor, a processing program, or firmware that is a combination thereof.

The controller 40 is a controller for receiving various control data for scanning and performing various controls such as X-ray control, gantry control and table control. The gantry 50 has an X-ray tube 60 and a detector 80 mounted on a rotating portion, and accommodates a subject placed on a table 70 in a central opening. Then, the X-ray tube 60 and the detector 80 arranged on the rotating part of the gantry 50 are configured so as to integrally rotate around the subject.

The X-ray tube 60 generates X-rays, and the X-rays emitted from the X-ray tube 60 pass through the subject 3 and are detected by the detector 80. The data collection unit 90 subjects the data detected by the detector 80 to processing such as amplification and integration, A / D-converts and outputs as detection data.

Further, as shown in FIG. 2, the data processing unit 3
Reference numeral 1 includes an image data generation unit 31a, a spine image selection unit 31b, and an imaging position angle setting unit 31c. Here, the image data generator 31a receives the detection data and generates image data.
The spine image selecting means 31b is for selecting the spine image region or the center line of the spine included in the image data. Then, the photographing position angle setting means 31c sets the photographing position and the photographing angle from the region of the spine image or the center line of the spinal column.

<Processing Procedure (1) of Tomography Planning Method> First, a basic method of the processing procedure of the tomography planning method will be described. This processing procedure is a basic processing procedure and is composed of the following steps ,. Each of these steps will be described step by step with reference to FIG.

Preliminary radiographing Preliminary radiographing (preliminary scan (scout scan)) is performed to grasp the shape of the spine and intervertebral shape (step 1 in FIG. 1). For example, imaging is performed so as to obtain an X-ray transmission image from the side surface of the subject. The detection data obtained by this preliminary imaging is converted into image data (image data of an X-ray fluoroscopic image from the side surface of the subject) by the image data generation unit 31a.

An example of an X-ray transmission image (scout image) obtained by such a preliminary scan is shown in FIG. As shown in FIG. 4, each part around the spinal column is obtained as a perspective image.
In the subsequent steps, the spine and intervertebral positions are detected from the image data of the X-ray transmission image.

Since an X-ray transmission image may be used for this preliminary imaging, for example, by moving the subject on the table 70 in the body axis direction without rotating the gantry of the X-ray tomography apparatus. The desired image is obtained.

Determination of Shooting Position The shooting position is obtained from the scout image obtained by the preliminary shooting described above (step 2 in FIG. 1).

FIG. 5 is an explanatory diagram showing an example of the relationship between a part of the spinal column by a scout image obtained by preliminary imaging and the imaging position and the imaging angle. As shown in FIG. 5, P1 to P6 are defined as the imaging positions between the vertebrae 100a to 100g of the spinal column. The processing for setting the shooting position is automatically performed by the shooting position angle setting means 31c, but by performing the processing while displaying an image on the display means 20, the operator can check the progress of the processing. Easy to grasp. Further, if necessary, it is possible to perform a correction process for correcting the determined area from the input means 10. Further, the operator sets the photographing position by referring to the scout image on the display means 20 while inputting the input means 1 by the operator.
It is also possible to manually set from 0.

Determination of Shooting Angle Then, the shooting angle is obtained from the scout image obtained by the preliminary shooting described above (step 3 in FIG. 1).

For example, in FIG. 5, photographing positions P1 to P
The inclinations of the planned slice lines c1 to c6 passing through 6 are set as the photographing angle (tilt angle). As shown in FIG. 5, the space between the vertebrae of the spinal column is defined as the imaging position, and the planned slice lines c1 to c6 that pass through this imaging position.
Can be set to obtain the tilt angles ω (ω1 to ω6) as the photographing angles for each.

Further, the point where each of the planned slice lines c1 to c6 intersects with the isocenter line IL can be used as a point for calculating the photographing position. The processing for setting the shooting angle is automatically performed by the shooting position angle setting means 31c. However, by performing the processing while displaying an image on the display means 20, the operator can see the progress of the processing. Easy to grasp. In addition, if necessary, a correction process for correcting the determined area is performed by the input unit 10.
It is also possible to start from.

Imaging Plan The imaging planning unit 32 makes an imaging plan for intervertebral tomography using the imaging position and the imaging angle obtained as described above (step 4 in FIG. 1).

Intervertebral imaging The imaging plan established as described above is used as imaging plan data. For example, when this scan plan data is supplied to the scan control unit 33, a control / drive command is transmitted from the scan control unit 33 to the controller unit 40 during tomography, and a desired intervertebral scan is performed. To be done.

At this time, the table 70 on which the subject is placed moves automatically or semi-automatically (becomes operable when there is an instruction from the operator after the display of the movement request), if necessary. Also, for the gantry 50, Table 7
After the movement of 0 is completed, the X-rays are emitted automatically or in accordance with the instruction of the operator by tilting in accordance with the determined photographing angle.

<Processing procedure (2) of tomography planning method> This processing procedure is a specific example of the tomography planning method characterized by extracting the region of the spine, and is roughly classified into the following. It is composed of each step of. Here, this step will be described step by step with reference to FIG. 6.

Preliminary radiographing Preliminary radiographing (preliminary scan (scout scan)) is performed to grasp the shape of the spine and intervertebral shape (step 1 in FIG. 6). For example, imaging is performed so as to obtain an X-ray transmission image from the side surface of the subject. The detection data obtained by this preliminary imaging is converted into image data (image data of an X-ray fluoroscopic image from the side surface of the subject) by the image data generation unit 31a. Incidentally, such a preliminary scan produces a scout image as shown in FIG.

Extraction of spine region Various image processing is performed on the image data of the X-ray transmission image obtained by the above-described preliminary scan to extract the spine image (step 2 in FIG. 6). For example,
An area of the spine or a contour of the spine is extracted by differentiating the pixel value of each pixel of the image data.

For example, it is assumed that there is a scout image as an X-ray transmission image from the side surface of the subject as shown in FIG. Here, 100a to 100d are spines, and 200 is a scapula. Since the scout image used in this processing is an X-ray transmission image, the spine and other bones may overlap depending on the site. Here, the spine 100a
And 100b (a part) and the scapula 200 are overlapped on the scout image.

Such a scout image (image data)
On the other hand, the point designated by the operator using the pointing device or the like of the input means 10 is the starting point (eg, point A in FIG. 7)
As a result, the spine image selection means 31b executes a process of sequentially selecting pixels in a range in which the amount of change in the pixel value (= X-ray transmission amount) is less than or equal to a certain value and smoothly changing, and spreading the pixels to the periphery. To do.

For example, the differential value of the image data of the scout image is sequentially examined in the direction of adjacent pixels centering on the pixel at the point A in the bone 100b of the spine, and the portion where the change in the differential value is not more than the predetermined value is vertebrae. Select it as an image and go. As a result, a region of the vertebral bone 100b that does not overlap the scapula 200 is selected (selection within the same region).

Further, there is a pixel in a portion within the range of the average pixel value ± α of the pixels in the already selected area and having the distance D less than a constant value from the end of the already selected area. In that case, the pixel is also selected (adjacent region selection). Then, the selection within the same area is continuously executed. Thereby, the region of the bone 100c of the spine is selected. Then, similarly, the region of the bone 100d is also selected. In this way, the extraction of the spine region is executed.

In the region where the vertebral bone 100b overlaps with the scapula 200, the pixel value (= X-ray transmission amount) is different from the above-mentioned point A, so one point in such region. The operator designates (point B) with a pointing device or the like of the input means 10. As a result, as in the case described above, the spine image selecting means 31b selects the region of the overlapping portion of the bone 100b of the spine and the scapula 200 and the region of the spine 100a.

Therefore, in the case shown in FIG. 7, by designating two points depending on the presence or absence of the overlap with another bone, the spine region is automatically selected after the designation. In the case shown in FIG. 7, image data with the scapula 200 removed is generated.

By performing such a semi-automatic selection (instruction input + automatic selection) of the spine region while displaying an image on the display means 20, the progress status can be easily grasped. Further, if necessary, it is possible to perform a correction process for deleting the selected area from the input means 10.

Imaging Position Determination From the regions of the spine obtained by the above-described spine region extraction processing, first, the facing surfaces between adjacent bones (FIGS. 8a and 8b).
Ask for. Then, the facing surfaces a and b are approximated as two straight lines or curves, and a position (P1 in FIG. 8) that is the center of these two straight lines or curves is set as the photographing position (step 3 in FIG. 6). ).

The processing for setting the photographing position as described above is automatically performed by the photographing position angle setting means 31c, but the processing is performed for the operator by displaying the image on the display means 20. It is easy to understand the progress.

Further, if necessary, it is also possible to perform a correction process for correcting the determined area from the input means 10. Further, the setting of the photographing position is performed by the display unit 2.
It is also possible for the operator to manually set from the input means 10 while referring to the scout image of 0.

Determination of Imaging Angle From the spine region obtained by the above-described spine region extraction processing, the facing faces (FIGS. 8a and 8b) between adjacent bones are obtained, and the angles of the facing faces a and b are determined. Determine an angle with an intermediate angle (bisecting angle).

Such processing is performed by the photographing position angle setting means 3
1c executes the above-described imaging position P1 and obtains the planned slice line c1 that forms the above-described bisecting angle as the imaging angle (step 4 in FIG. 6).

The processing for setting the photographing angle as described above is automatically performed by the photographing position angle setting means 31c, but the processing is performed for the operator by displaying the image on the display means 20. It is easy to understand the progress. Further, if necessary, it is possible to perform a correction process for correcting the determined area from the input means 10.

Imaging Plan Using the imaging position and the imaging angle obtained as described above, the imaging planning unit 32 makes an imaging plan for intervertebral tomography (step 5 in FIG. 6).

Intervertebral Imaging The imaging plan established as described above is used as imaging plan data. For example, when this scan plan data is supplied to the scan control unit 33, a control / drive command is transmitted from the scan control unit 33 to the controller unit 40 during tomography, and a desired intervertebral scan is performed. To be done.

At this time, the table 70 on which the subject is placed moves automatically or semi-automatically (becomes operable when an operator's instruction is given after the display of the movement request), if necessary. Also, for the gantry 50, Table 7
After the movement of 0 is completed, the X-rays are emitted automatically or in accordance with the instruction of the operator by tilting in accordance with the determined photographing angle.

In the specific example of the processing procedure (2), the description has been made assuming that the photographing position and the photographing angle are determined from the result of recognizing the region. However, the photographing position and the photographing angle are recognized from the recognized region. It is possible to determine either one and directly determine the other from the scout image before the region recognition.

<Processing procedure (3) of tomography planning method> This processing procedure is a specific example of the tomography planning method characterized by extracting the center line of the spine to obtain the imaging angle. below,,,,,,
It is composed of each step of. Here, this step will be described step by step with reference to FIG. 9.

Preliminary Imaging Preliminary imaging (preliminary scan (scout scan)) is performed to grasp the shape of the spine and intervertebral shape (step 1 in FIG. 9). For example, imaging is performed so as to obtain an X-ray transmission image from the side surface of the subject. The detection data obtained by this preliminary imaging is converted into image data (image data of an X-ray fluoroscopic image from the side surface of the subject) by the image data generation unit 31a.

Determination of Shooting Position The shooting position is determined from the scout image obtained by the preliminary shooting described above (step 2 in FIG. 9).

The processing for setting the photographing position is automatically performed by the photographing position angle setting means 31c. However, the processing is performed for the operator by displaying the image on the display means 20. It is easy to understand the progress.

Further, if necessary, it is also possible to perform a correction process for correcting the determined area from the input means 10. Further, the setting of the photographing position is performed by the display unit 2.
It is also possible for the operator to manually set from the input means 10 while referring to the scout image of 0.

Detecting the center line of the spinal column From the region of the spine obtained by the above-described spine region extraction processing, a line (spine center line) smoothly connected through the center points of the respective vertebrae of the spinal column is selected by the spine image selecting means 31b. Is set (step 3 in FIG. 9). An example of this spinal center line d is shown in FIG.

Regarding the line smoothly connected when setting the spine center line, after the center points of the respective vertebrae of the spinal column are obtained, the center points are smoothly connected using various functions such as a spline function. Can be achieved with.

The processing for detecting the center line of the spine is automatically performed by the spine image selecting means 31b. However, by performing the processing while displaying the image on the display means 20, the operator can check the progress status. It becomes easy to understand.

Further, if necessary, it is also possible to perform correction processing for correcting the determined spinal center line from the input means 10. Further, the setting of the spine center line can be manually set by the operator from the input unit 10 while referring to the scout image of the display unit 20.
In this case as well, both the case where the whole spine center line is manually input (all manual input) and the case where the spine image selection means 31b generates a smooth curve after inputting some points (semi-manual) It doesn't matter.

Determination of Shooting Angle The angle of a line (normal line) on the shooting position obtained by the above processing and intersecting at right angles with the center line of the spine obtained by the above processing is the shooting angle (tilt angle). Is set by the photographing position angle setting means 31c (step 5 in FIG. 9).

That is, as shown in FIG. 10, by setting the planned slice lines c1 to c6 between the vertebrae of the spinal column, the tilt angle ω can be obtained for each. Also,
Each of the planned slice lines c1 to c6 is an isocenter line I
The point that intersects L can be used as a point for calculating the shooting position.

The processing for determining the shooting angle is automatically performed by the shooting position angle setting means 31c. However, by performing the processing while displaying an image on the display means 20, the progress status for the operator can be obtained. It becomes easy to understand.

Further, if necessary, it is possible to perform a correction process for correcting the determined photographing angle from the input means 10. Further, the operator sets the photographing angle while referring to the scout image on the display means 20.
It is also possible to manually set from 0.

Imaging Plan The imaging planning unit 32 makes an imaging plan for intervertebral tomography using the imaging position and the imaging angle obtained as described above (step 4 in FIG. 9).

Intervertebral Imaging The imaging plan established as described above is used as imaging plan data. For example, when this scan plan data is supplied to the scan control unit 33, a control / drive command is transmitted from the scan control unit 33 to the controller unit 40 during tomography, and a desired intervertebral scan is performed. To be done.

At this time, the table 70 on which the subject is placed moves automatically or semi-automatically (it becomes operable when the operator gives an instruction after the display of the movement request), if necessary. Also, for the gantry 50, Table 7
After the movement of 0 is completed, the X-rays are emitted automatically or in accordance with the instruction of the operator by tilting in accordance with the determined photographing angle.

<Processing procedure (4) of tomography planning method> This processing procedure is a specific example of the tomography planning method characterized by extracting the center line of the spine to obtain the imaging position. ,,, and each step. Here, this step will be described step by step with reference to FIG. 11.

Preliminary radiographing Preliminary radiographing (preliminary scan (scout scan)) is performed to grasp the shape of the spine and intervertebral shape (step 1 in FIG. 11). For example, imaging is performed so as to obtain an X-ray transmission image from the side surface of the subject. The detection data obtained by this preliminary imaging is converted into image data (image data of an X-ray fluoroscopic image from the side surface of the subject) by the image data generation unit 31a. Incidentally, such a preliminary scan produces a scout image as shown in FIG.

Detecting the center line of the spinal column The spine image selecting means 31b sets a line (spine center line) smoothly connected through the center points of the respective vertebrae of the spinal column (FIG. 1).
1 step 3).

The spine center line d is already as shown in FIG. 10, and the smoothly connected line when setting the spine center line can be realized by using various curves such as spline functions. .

Although the processing for detecting the center line of the spine is automatically performed, the progress can be easily grasped by performing the processing while displaying an image on the display means 20. Further, it is possible to perform a correction process for correcting the determined area, if necessary.

Determination of Imaging Position Then, the intervertebral position to be the slice position is determined by referring to the pixel value of the image data on the obtained spine center line. FIG. 12 is a graph showing the pixel values of the image data on the spine center line, and it can be seen that the pixel values of each vertebra of the spinal column are large and the pixel values are small between the intervertebral vertebrae.

Therefore, the photographing position setting means 31c causes the area where the pixel value on the spine center line is small (for example, a certain range (a range of the size of each vertebra of the spine)).
(Local minimum point in) is detected to determine the shooting position (Fig. 1
1 step 3).

Since the pixel value amplitude has many small peaks and valleys in the unprocessed pixel value distribution, the processing can be facilitated by detecting the minimum point after smoothing the pixel value data by filtering or the like. . Further, when the X-ray fluoroscopic image is used to obtain the scout image, the minimum point is the intervertebral space that is to be obtained, but with other methods (MRI etc.), the pixel value may be inverted and the maximum value may be obtained. Sometimes I ask for points.

Although the processing for determining the photographing position is automatically performed, the progress can be easily grasped by performing the processing while displaying an image on the display means 20. Further, if necessary, it is possible to perform a correction process for correcting the determined area from the input means 10. Further, the setting of the photographing position can be manually set by the operator from the input unit 10 while referring to the scout image on the display unit 20.

Determination of Shooting Angle The angle of the line (normal line) on the shooting position obtained by the above processing and intersecting at right angles with the center line of the spine obtained by the above processing is the shooting angle (tilt angle). Is set by the photographing position angle setting means 31c (step 5 in FIG. 11).

That is, as shown in FIG. 10, it is possible to determine the tilt angle ω for each of the planned slice lines c1 to c6 between the vertebrae of the spinal column. Also,
Each of the planned slice lines c1 to c6 is an isocenter line I
The point that intersects L can be used as a point for calculating the shooting position.

The processing for determining the shooting angle is automatically performed by the shooting position angle setting means 31c. However, by performing the processing while displaying an image on the display means 20, the operator can check the progress status. It becomes easy to understand.

Further, if necessary, it is also possible to perform correction processing for correcting the determined photographing angle from the input means 10. Further, the operator sets the photographing angle while referring to the scout image on the display means 20.
It is also possible to manually set from 0.

Imaging Plan The planning processing means 27 makes an imaging plan for intervertebral tomography using the imaging position and the imaging angle obtained as described above (step 6 in FIG. 9).

Intervertebral Imaging The imaging plan established as described above is used as imaging plan data. For example, when this scan plan data is supplied to the scan control unit 33, a control / drive command is transmitted from the scan control unit 33 to the controller unit 40 during tomography, and a desired intervertebral scan is performed. To be done.
At this time, the top plate on which the subject is placed moves automatically or semi-automatically (becomes operable when there is an instruction from the operator after the display of the movement request) as necessary. Further, with respect to the gantry, after the movement of the top plate is completed, X-ray irradiation is performed by tilting according to a predetermined imaging angle automatically or according to an instruction of the operator.

<Processing procedure (5) of tomography planning method> This processing procedure is characterized in that the region of the spine is extracted to obtain the imaging position, and the center line of the spine is extracted to obtain the imaging angle. This is a specific example of the tomography planning method, and is roughly divided into the following steps ,. Here, with reference to FIG.
This step will be described step by step.

Preliminary Imaging Preliminary imaging (preliminary scan (scout scan)) is performed to grasp the shape of the spine and intervertebral shape (step 1 in FIG. 13). For example, imaging is performed so as to obtain an X-ray transmission image from the side surface of the subject. The detection data obtained by this preliminary scan is converted into image data (image data of an X-ray fluoroscopic image from the side surface of the subject) by the image data generation unit 31a. Incidentally, such a preliminary scan produces a scout image as shown in FIG.

Area Extraction of Spine The spine image selecting means 31b performs various image processing on the image data of the X-ray transmission image obtained by the above-described preliminary scan to extract the image of the spine (FIG. 13 Step 2). For example, in the same manner as the case of the area extraction processing in the above-described processing procedure (2), the area or contour of the spine is extracted by differentiating the pixel value data or the like.

By performing such a semi-automatic selection (instruction input + automatic selection) of the spine region while displaying an image on the display means 20, the progress status can be easily grasped. Further, if necessary, it is possible to perform a correction process for deleting the selected area from the input means 10.

Imaging Position Determination From the spine region obtained by the above-described spine region extraction processing, first, the facing surfaces between adjacent bones (FIGS. 8a and 8b).
Ask for. Then, the facing surfaces a and b are approximated as two straight lines or curves, and the position (P1 in FIG. 8) that is the center of these two straight lines or curves is set as the photographing position (step 3 in FIG. 13). ).

The processing for setting the photographing position as described above is automatically performed by the photographing position angle setting means 31c, but the processing is performed for the operator by displaying the image on the display means 20. It is easy to understand the progress.

Further, if necessary, it is possible to perform a correction process for correcting the determined area from the input means 10. Further, the setting of the photographing position is performed by the display unit 2.
It is also possible for the operator to manually set from the input means 10 while referring to the scout image of 0.

Detecting the center line of the spinal column From the region of the spine obtained by the above-described preliminary scan result or the extraction process of the spine region, a line (spine center line) smoothly connected through the center points of the respective vertebrae of the spinal column is formed. The image selecting means 31b makes the setting (step 4 in FIG. 13). An example of this spinal center line d is shown in FIG.

The smoothly connected line when setting the spinal center line can be realized by using various curves such as a spline function. Although the processing for detecting the center line of the spine is automatically performed, the display means 2
It is easy to understand the progress status by displaying the image on the screen 0. Further, it is possible to perform a correction process for correcting the determined area, if necessary.

Determination of Imaging Angle The imaging angle (tilt angle) is the angle of the line (normal line) on the imaging position obtained by the above processing and intersecting at right angles with the spinal center line obtained by the above processing. Is set by the photographing position angle setting means 31c (step 5 in FIG. 13).

That is, as shown in FIG. 10, it is possible to determine the tilt angle ω for each of the planned slice lines c1 to c6 between the vertebrae of the spinal column. Also,
Each of the planned slice lines c1 to c6 is an isocenter line I
The point that intersects L can be used as a point for calculating the shooting position.

The processing for determining the photographing angle is automatically performed by the photographing position angle setting means 31c. However, by performing the processing while displaying an image on the display means 20, the progress situation for the operator. It becomes easy to understand.

Further, if necessary, it is possible to perform a correction process for correcting the determined photographing angle from the input means 10. Further, the operator sets the photographing angle while referring to the scout image on the display means 20.
It is also possible to manually set from 0.

Imaging Plan The imaging plan unit 32 makes an imaging plan for intervertebral tomography using the imaging position and imaging angle obtained as described above (step 4 in FIG. 13).

Intervertebral imaging The imaging plan established as described above is used as imaging plan data. For example, when this scan plan data is supplied to the scan control unit 33, a control / drive command is transmitted from the scan control unit 33 to the controller unit 40 during tomography, and a desired intervertebral scan is performed. To be done.

At this time, the table 70 on which the subject is placed moves automatically or semi-automatically (becomes operable when an operator's instruction is given after the display of the movement request), if necessary. Also, for the gantry 50, Table 7
After the movement of 0 is completed, the X-rays are emitted automatically or in accordance with the instruction of the operator by tilting in accordance with the determined photographing angle.

<Structure (2) of tomography apparatus> Another structure of the main part of the tomography apparatus used for the processing of each specific example of the tomography planning method as described above will be described with reference to FIG.

In each of the above specific examples, the spine image selecting means 31b calculates the spine center line and executes the process of recognizing the spine region. Therefore, the spine image selection unit 31b is configured to have a line setting unit 31d and a region recognition unit 31e.

Here, the line setting section 31d executes the process of setting the spine center line from the image data generated from the detection data of the preliminary scan. The area recognition unit 31e also executes a process of extracting the area or contour of the spine from the image data generated from the detection data of the preliminary scan.

Further, in each of the above specific examples, the photographing position angle setting means 31c executes the process of setting the photographing position and the photographing angle. Therefore, the photographing position angle setting means 31c includes a photographing position setting unit 31f and a photographing angle recognition unit 31g.
And are configured to have.

Here, the photographing position setting section 31f executes the process of setting the photographing position from the image data generated from the detection data of the preliminary scan or the region of the spine or the center line of the spine. Also, the photographing angle recognition unit 31g
Performs a process of recognizing the imaging angle from the image data generated from the detection data of the preliminary scan or the region of the spine or the center line of the spine.

<Effects Obtained by Each Specific Example of the Method of the Present Invention: Comparison with Conventional Example> According to each specific example of the method of the present invention,
The following effects (1) to (4), which are not present in conventional examples, are obtained.

According to the tomographic imaging planning method and the tomographic imaging apparatus for performing the preliminary imaging and determining the imaging position and the imaging angle from the preliminary imaging result, the imaging position and the imaging angle are automatically determined. It becomes possible to easily set the imaging position and the imaging angle according to the subject at the time of tomography.

Preliminary photographing is performed, and the region of each vertebra of the spinal column is recognized from the result of the preliminary photographing around the spinal column,
Set the intermediate position of the facing surface of each vertebra of the recognized spine to determine the imaging position, and recognize the angle between each vertebra of the spinal column from the result of preliminary imaging around the spinal column According to the tomography planning method and the tomography apparatus, the imaging position and the imaging angle are automatically determined, and the imaging position is accurately determined, and the imaging according to the subject during the intervertebral tomography is performed. It is possible to easily set the position and the photographing angle.

Preliminary photographing is performed, and the region of each vertebra of the spinal column is recognized from the result of the preliminary photographing around the spinal column,
According to the tomographic imaging planning method and tomographic imaging apparatus, the imaging angle is determined from the facing surface of each vertebra of the recognized spinal column, and the imaging position is determined from the result of preliminary imaging around the spinal column.
The imaging position and imaging angle are automatically determined, and the imaging angle is also accurately determined, making it possible to easily set the imaging position and imaging angle according to the subject when performing intervertebral tomography. Become.

Preliminary photographing is performed, the center line of the spinal column is obtained from the result of the preliminary photographing, the position between the bones is detected from the contour of each vertebra of the spinal column, and the position is determined as the photographing position. According to the tomography planning method and the tomography apparatus that determine the vertical direction as the tomography angle, the imaging position and the imaging angle are automatically determined, and the imaging angle is accurately determined. In this case, it is possible to easily set the imaging position and the imaging angle according to the subject.

Preliminary photographing is performed, the center line of the spinal column is obtained from the result of the preliminary photographing, the position between each vertebra is detected from the pixel value on the center line of the spinal column, and the position is determined as the photographing position. According to the tomography planning method and the tomography apparatus that determine the imaging angle from the imaging result, the imaging position and the imaging angle are automatically determined, and the imaging position is accurately determined. It is possible to easily set the imaging position and the imaging angle according to the sample.

The above-mentioned tomographic feature is characterized in that the pixel value of the image of the preliminary photographing result on the center line is smoothed to obtain an extreme value, and the position between the respective vertebrae of the spinal column is detected and set as the photographing position. According to the imaging planning method and the tomography apparatus, the imaging position is accurately determined, and it becomes possible to easily set the imaging position and the imaging angle according to the subject during the intervertebral tomography. .

Preliminary photographing is performed, and the region of each vertebra of the spinal column is recognized from the result of the preliminary photographing around the spinal column,
Determine the shooting position from the face facing each vertebra of the recognized spinal column, determine the center line of the spinal column from the results of preliminary imaging,
According to the tomography planning method and the tomography apparatus that determine the direction perpendicular to the center line of the spinal column as the tomography imaging angle, the imaging position and the imaging angle are automatically determined, and the imaging position and the imaging angle are accurately determined. Therefore, it becomes possible to easily set the imaging position and the imaging angle according to the subject at the time of tomographic imaging between the vertebrae.

<Other Concrete Examples and Effects Obtained> In the above-mentioned concrete examples, the description has been made focusing on the case where the spine center line is obtained as a result of the selection of the spine image, but as described briefly in the above concrete examples. In addition, the operator can directly input the spinal center line with a pointing device or the like.

It is also possible to determine the photographing position and the photographing angle with reference to the spine center line thus manually input. With this procedure, it is possible to set an arbitrary spinal center line, and it is possible to deal with the case where the operation of automatic spine image selection is not perfect in the case of a specific spine shape. become. Further, the process of selecting a spine image is not necessary.

Further, the operator does not set the spine center line as a line when the operator inputs it, but the operator designates several points, and a smooth curve passing through the designated points is set. It can also be set by the spine image selection means 31b.

With this procedure, it is possible to set an arbitrary spinal center line even when the spine has a specific shape, and the operation is easier than when all of the spinal center lines are manually operated. Has the advantage of becoming. In addition to the point designation, vector designation is also possible.

In the above specific example, the top plate position and the tilt angle are obtained after the photographing position is set, but the top plate position and the tilt angle may be obtained at the same time during the setting of the photographing position. . By doing so, the processing is performed quickly.

Although the photographing position is automatically determined in the above-mentioned specific example, it may be inputted by the operator. In this case, when the imaging position between the vertebrae is input with a pointing device or the like, the imaging position angle setting means 3
1c refers to the data of the surrounding scout image at that position, performs partial selection of the spine image and detects the contour of the image. It can also be determined automatically. Also in this case, it is possible to set an arbitrary imaging position and an imaging angle even when the spine has a specific shape, and there is an advantage that accurate and easy scanning can be performed.

In the above description of each specific example, the X-ray tomography apparatus was used.
It can be realized even by an RI (Magnetic Resonance Imaging) device. In the case of using such an MRI apparatus, the imaging position and the imaging angle may be determined using an image obtained by performing preliminary tomography instead of the X-ray projection image as a preliminary scan.

[0139]

As described above in detail, according to the tomographic imaging planning method and the tomographic imaging apparatus, the preliminary imaging is performed, and the imaging position and the imaging angle are determined from the preliminary imaging result.
Since the imaging position and the imaging angle are automatically determined, it becomes possible to easily set the imaging position and the imaging angle according to the subject at the time of intervertebral tomography.

Further, by detecting the region of the spine and the center line of the spinal column and obtaining the photographing position and the photographing angle from them, more accurate and easy processing can be realized. .

[Brief description of drawings]

FIG. 1 is a flowchart showing a basic processing procedure of a tomography planning method of the present invention.

FIG. 2 is a configuration diagram showing a configuration example of a main part of a tomography apparatus used in the tomography planning method of the present invention.

FIG. 3 is a configuration diagram showing the overall configuration of a tomography apparatus used in the tomography planning method of the present invention.

FIG. 4 is an explanatory diagram showing an example of a scout image obtained as a preliminary imaging result in the tomography planning method of the present invention.

FIG. 5 is an explanatory diagram showing a state of determining a shooting position and a shooting angle from a scout image obtained as a preliminary shooting result in the tomography planning method of the present invention.

FIG. 6 is a flowchart showing a processing procedure of a specific example of the tomography planning method of the present invention.

FIG. 7 is an explanatory diagram showing a state in which a spine image is selected from scout images obtained as preliminary imaging results in a specific example of the tomographic imaging planning method of the present invention.

FIG. 8 is an explanatory diagram showing a state of determining a photographing position and a photographing angle from a scout image obtained as a preliminary photographing result in the specific example of the tomography planning method of the present invention.

FIG. 9 is a flowchart showing a processing procedure of another specific example of the tomography planning method of the present invention.

FIG. 10 is an explanatory diagram showing a state of determining a shooting position and a shooting angle from a scout image obtained as a preliminary shooting result in another specific example of the tomography planning method of the present invention.

FIG. 11 is a flowchart showing a processing procedure of another specific example of the tomography planning method of the present invention.

FIG. 12 is an explanatory diagram showing a state when an imaging position is determined in another specific example of the tomographic imaging planning method of the present invention.

FIG. 13 is a flowchart showing a processing procedure of another specific example of the tomography planning method of the present invention.

FIG. 14 is a configuration diagram showing a configuration example of a main part of a tomography apparatus used in each specific example of the tomography planning method of the present invention.

[Explanation of symbols]

 10 input means 20 display means 30 control section 31 data processing section 32 imaging planning section 33 scan control section 40 controller section 50 gantry 60 X-ray tube 70 table 80 detector 90 data acquisition section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsumi Atsu 127 GE Yokogawa Medical Systems Co., Ltd. 4-7 Asahigaoka, Hino City, Tokyo

Claims (6)

[Claims] 1. A preliminary imaging around the spinal column is performed, and a position between each vertebra of the spinal column is set as an imaging position from the result of the preliminary imaging, and a space between each vertebra of the spine is determined from the result of the preliminary imaging. The tomography planning method is characterized in that the angle of is recognized as the imaging angle and the imaging position and the imaging angle are determined. 2. A position setting means for setting a position between the vertebrae of the spinal column to determine an imaging position based on a result of performing preliminary imaging around the spinal column, and a result of performing preliminary imaging around the spinal column. A tomography apparatus further comprising: an angle recognition unit that further recognizes an angle between each vertebra of a spinal column and determines an imaging angle. 3. A region recognition unit that recognizes a region of each vertebra of the spine based on a result of preliminary imaging around the spinal column, and an intermediate position between facing surfaces of each vertebra of the spine recognized by the region recognition unit. A position setting means for determining the photographing position by setting the angle, and an angle recognition means for recognizing the angle between the vertebrae of the spinal column based on the result of preliminary photographing around the spinal column and determining the photographing angle. A tomography apparatus characterized in that 4. A position setting means for setting a position between the vertebrae of the spinal column to determine an imaging position based on a result of performing preliminary imaging around the spinal column, and a result of performing preliminary imaging around the spinal column. A region recognizing unit that recognizes a region of the spine around the position set by the position setting unit, and an imaging angle is determined by a bisector of an angle sandwiched between the regions recognized by the region recognizing unit. A tomography apparatus comprising: an angle determining unit. 5. A position setting means for setting a position between the vertebrae of the spinal column to determine an imaging position based on a result of performing preliminary imaging around the spinal column, and a result of performing preliminary imaging around the spinal column. Line setting means for further setting the center line of the spine, and angle recognizing means for recognizing the angle between the vertebrae from the center line of the spine set by the line setting means and determining the imaging angle. Tomography apparatus characterized by. 6. A line setting means for setting a center line of the spine based on a result of preliminary imaging around the spine, and a distance between each vertebra based on a pixel value on the center line of the spine set by the line setting means. Position setting means for setting the position of the position to determine the shooting position, and angle recognition means for recognizing the angle between the vertebrae of the spinal column from the result of performing preliminary imaging around the spinal column and determining the shooting angle, A tomography apparatus comprising: