JP2001178713A - X-ray ct system, operation console, control method therefor and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute reliable diagnosis and to reduce an exposure amount of a subject by improving precision of information for automatically controlling an X-ray amount in an X-ray CT system or apparatus. SOLUTION: In this X-ray CT system, when photographing a tomographic image of the subject, a process for getting a positioning image is executed (S1). Based on the result, not to mention positioning information, a control value of an X-radiation amount whose parameter is a carrying direction of the subject is decided (S2). Because the control value of the X-radiation amount isn't necessarily accurate, the control value of the X-radiation amount is corrected on the basis of the tomographic image obtained by the first main scan (S6). In the later scans, processes are executed on the basis of the corrected control value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an X-ray CT system for obtaining a tomographic image of a patient by X-ray irradiation, an operation console, a control method thereof, and a storage medium.

[0002]

2. Description of the Related Art X-ray CT (Computerized Tomograph)
y) and the system, the subject is irradiated with a fan-shaped X-ray beam from the X-ray tube, and the transmitted X-ray is converted into an X-ray of a one-dimensional array including a plurality of detection elements arranged in accordance with the spread of the fan-shaped beam. Measure with the line detector.

[0003] The measurement of the transmitted X-ray is performed in a plurality of view directions while rotating the X-ray tube and the X-ray detector around the subject. Such measurement of transmitted X-rays is called scanning. Then, an X-ray tomographic image (image data) is reconstructed based on the measurement data of a plurality of views obtained by the scan, and is displayed on a display device such as a CRT.

[0004] The pixel value of an X-ray tomographic image to be displayed (referred to as a CT value in the case of an X-ray tomography apparatus) is determined by the transmittance of X-rays.
It is determined to be.

[0005] The pixel value of such image data is converted into display data of about 256 gradations to display an image. In this case, the number of gradations of the display data is generally about 256 gradations in which the density is processed by 8 bits, and the pixel value of the image data is −10.
It is not realistic to prepare and display a wide range of gradations such as 00 to +2000.

For example, when the pixel values of the organ of the subject to be noted are distributed between -150 and +150 in CT value, a different concept of the window width is introduced, and the range of the window width is introduced. The display data is converted so that the image can be displayed in 256 gradations, and the image is displayed in shades.
The portion exceeding the upper limit is displayed in white or black, and the portion less than the lower limit is displayed in black or white. By doing so, the image data of the focused portion can be contained in the displayable range by gradation, and can be displayed as a change in contrast.

By the way, the intensity of the transmitted X-rays naturally depends on the configuration of the portion of the subject to which the X-rays are irradiated. That is, since air transmits X-rays, attenuation of X-rays is small because the lungs are present in the chest, but attenuation is large because there are many organs in the abdomen. The subjects, that is, the subjects, also have different body shapes.

Therefore, with such an X-ray CT apparatus,
When scanning is performed, the S / N ratio of the detection signal in a portion where the attenuation of the X-ray is large is worse than that in a portion where the attenuation is small. On the other hand, if scanning is performed with a large amount of X-ray irradiation, a high S / N ratio can be obtained irrespective of the part, but unnecessary exposure is performed, so that it must be avoided.

Therefore, there is a need for a technique for setting the optimum X-ray dose in accordance with the measurement site (position) of the subject.
As a typical example of this technology, for example,
No. 121 publication.

This document discloses a so-called Au that automatically controls a tube current applied to an X-ray tube for determining an X-ray irradiation amount for each slice.
It discloses to mA (hereinafter referred to as Auto mA). By using this technique, it is possible to set an appropriate X-ray irradiation amount according to the chest and abdomen of a subject having different X-ray attenuations, and to suppress unnecessary exposure and to achieve a sufficient S in image reconstruction processing. / N ratio signals can be extracted.

That is, in this Auto mA, the tube current of the X-ray tube differs depending on the slice position and the body shape of the subject. Therefore, the condition of Auto mA is
It must be determined based on the slice position and body shape.

In the above-mentioned Auto mA, first, an X-ray tube and an X-ray detector are arranged so as to face each other so as to sandwich the subject, and the X-ray tube is positioned directly above the subject, and Is fixed immediately below the subject (the angular position is set to zero degree), the subject is gradually transported, and a scan similar to a normal X-ray photography (hereinafter, referred to as a scout scan) is performed to perform X-rays. Obtain a perspective image. Next, the X-ray tube and the X-ray detector are set to 90
Fixed by rotating it by 90 degrees (angular position is 90 degrees), that is, X
A similar scout scan is performed by setting the X-ray tube and the X-ray detector right beside the subject to obtain an X-ray fluoroscopic image. It should be noted that a scout scan at an angle of 0 degree may be performed after performing a scout scan at an angle position of 90 degrees.

By using the detected values of transmitted X-rays in the scout scan from two directions in this manner, information on the width and thickness (body type) at each position of the subject can be obtained. Because the cross section of the subject is not circular but almost elliptical,
Noise occurs due to the shape. Therefore, the ellipticity is calculated based on the above information, and the auto current for automatically controlling the tube current of the X-ray tube for each slice so that the noise is within a predetermined range.
Set A and perform a normal scan (main scan).

[0014]

In some cases, a contrast medium is injected into a vein of a subject, and an X-ray tomographic image is taken at each time.

For example, in the liver, blood at a tumor site such as cancer cells flows faster than at a normal site. Therefore, first, a scan is performed to know the state when the contrast agent is not injected. Then, in order to find a tumor such as a cancer cell, an early stage after the injection of the contrast agent (for example, 20 seconds after the injection of the contrast agent)
At this stage, scanning is performed to obtain an X-ray tomographic image. Also,
For normal cells, the blood flow is slower than that of the tumor, so a good time to identify normal cells (eg 1 minute)
Wait for, and scan again. At this time, since the contrast agent has already flowed away in the vicinity of the tumor, it is easy to distinguish the contrast agent.

The doctor makes a diagnosis by comparing the X-ray tomographic images obtained at each timing.

In each scan (three times in the above case),
Before that, the scan condition is scheduled based on the above-described scout scan, that is, the scan condition is set to Auto mA.

However, the problem here is that Auto mA
Is that the information acquired during the scout scan may not have sufficient accuracy in order to perform the scan. The main factor is that the subject is not correctly lying at the center of the transport table. Therefore, the influence may appear during the subsequent main scan for obtaining the tomographic image as described above.

The present invention has been made in view of such a problem, and makes information for automatic control of X-ray dose in an X-ray CT system or apparatus to be more accurate, thereby providing more reliable diagnosis. It is an object of the present invention to provide an X-ray CT system, an operation console, a control method therefor, and a storage medium that make it possible to minimize the exposure dose of a subject while making it possible.

[0020]

In order to solve such a problem, for example, an X-ray CT system of the present invention has the following configuration. That is, the opposing X-ray generator and the X-ray detector constituted by the X-ray detection array are rotated, and the X-ray tomographic image of the subject located between the X-ray generator and the X-ray detector What is claimed is: 1. An X-ray CT system for reconstructing an image, comprising: an X-ray fluoroscopic image extracting means for extracting an X-ray fluoroscopic image of a subject in a body axis direction in a plurality of directions on a plane perpendicular to the body axis; Based on each X-ray fluoroscopic image extracted by the fluoroscopic image extraction means, calculation for calculating each position in the body axis direction of the subject and a control value of the X-ray irradiation amount of the X-ray tube for each position. Means for irradiating the subject with X-rays in accordance with each position in the body axis direction and the X-ray irradiation amount calculated by the calculation means, and at a predetermined timing of elapse of time, a predetermined diagnostic site in the body axis direction Main scanning means for reconstructing a series of X-ray tomographic images of the subject in a range including: Scanning means for correcting the control value of the X-ray irradiation amount at each position calculated by the calculating means according to the series of X-ray tomographic images and the evaluation value based on the position in the body axis direction. It is characterized by including.

According to this configuration, in the main scan, the X-ray tomographic image is corrected at least once, and an X-ray tomographic image can be obtained in accordance with a more accurate X-ray generation amount.

Here, according to a preferred embodiment of the present invention, the correcting means calculates a standard deviation of a tomographic image at each displacement.
The calculated control value of the X-ray irradiation amount is corrected so as to approximate a preset target standard deviation. Since the target standard deviation is equivalent to the image quality, the required image quality can be maintained, and the X-ray irradiation amount can be prevented from being more than necessary.

[0023]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of an X-ray CT system according to the embodiment. As shown, the system comprises:
A gantry device 100 for irradiating the subject with X-rays and detecting X-rays transmitted through the subject, various operation settings are performed on the gantry device 100, and based on data output from the gantry device 100. The operation console 200 is configured to reconstruct and display an X-ray tomographic image.

The gantry apparatus 100 has the following configuration, including the main controller 1 that controls the entire system.

Reference numeral 2 denotes an interface for performing communication with the operation console 200. Reference numeral 3 denotes a gantry having a hollow portion for transporting a subject (a subject) lying on the table 12. X-ray tube 4 (X
A collimator 6 having a slit for defining an X-ray irradiation range is provided.

The gantry 3 has an X-ray detector having a plurality (approximately 1000) of detection elements for detecting X-rays transmitted through the subject along the circumference of the cavity of the gantry as shown in the figure. And a data collection unit 9 for collecting data obtained from the detection unit 8. The X-ray tube 4 and the detection unit 8 are provided at positions facing each other with a hollow portion therebetween, and are rotatable around the gantry 3 in a state where the relationship is maintained. This rotation is performed by a rotation motor 10 driven by a drive signal from a motor controller 11.
Done by Also, a table 12 on which the subject is placed
Is transported in the body axis direction (Z-axis direction) of the subject, and is driven by the table motor 13.

The main controller 1 analyzes various commands received via the I / F 2, and based on the analyzed commands, the X-ray tube controller 5 and the motor controller 1
1. Various control signals are output to the table motor controller 14. Further, the main controller 1 transmits the data collected by the data collection unit 9 to the I / F 2
Also, processing for sending to the operation console 200 via the.

On the other hand, the operation console 200 is a so-called workstation, as shown in the figure, a CPU 51 for controlling the entire apparatus, a ROM 52 for storing a boot program and a BIOS, and an RA functioning as a main storage.
M53 (the area of the Auto mA table described later is also secured), and the following configuration is provided.

The HDD 54 is a hard disk drive in which an OS, a diagnostic program for giving various instructions to the gantry device 100 and reconstructing an X-ray tomographic image based on data received from the gantry device 100 are stored. Have been.

The VRAM 55 is a memory for expanding image data to be displayed. The image data and the like can be displayed on the CRT 56 by expanding the image data and the like. 57 and 58 are a keyboard and a mouse for performing various settings. An interface 59 communicates with the gantry device 100.

An example of the processing in the embodiment having the above configuration will be described with reference to FIGS. 1 and 2 to 6.

FIG. 4 shows a main program relating to operation processing in the embodiment. This program is
This is stored in the HDD 54 of the operation console 200, and is loaded into the RAM 53 after the power is turned on.
1 is executed.

First, in step S1, a subject (subject) is laid on the table 12, and then a positioning image is input (a scout scan is performed).

More specifically, the motor controller 11 is controlled so that the X-ray tube 4 (including the collimator 6) is located directly above the subject (the detection unit 8 is located immediately below the subject). ). At the fixed position, the table 12 is transported in the Z-axis direction, and the same imaging (scanning) as a normal planar X-ray image (X-ray fluoroscopic image) is performed with a preset X-ray irradiation amount. Receive the detected data.

Then, the scan is completed at an appropriate position, and the X-ray tube 4 and the detection unit 8 are rotated by 90 degrees along the circumference of the gantry 3 to be fixed at that position. The detection unit 8 scans the plane X-ray image so as to sandwich the subject from the side, that is, this time, when viewed from the horizontal direction.

As a result, as shown in FIG.
It becomes possible to acquire a positioning image of the subject lying above. In other words, an X-ray fluoroscopic image is extracted.

Next, in step S2, the CPU 51 calculates the ellipticity based on the width and height in the displacement of each Z-axis and the cross-sectional area based on the attenuation of X-rays on each Z-axis from the two positioning images obtained. Is calculated, the X-ray irradiation amount (tube current value) based on the displacement of each Z axis suitable for the subject is determined, and is created in the RAM 53 as the Auto mA table 53a.

The structure of the Auto mA table is as shown in FIG. 3, in which the displacement (unit: mm) of the Z-axis at the absolute position in the gantry device 100 and the value of the tube current (unit: mA) at that position. Composed of combinations. In other words, the control value of the X-ray irradiation amount of the X-ray tube at each position in the Z-axis direction is calculated.

As described above, the Auto mA table 53
When a is created, the process proceeds to step S3, in which the acquired positioning image is displayed on the CRT 56, and a technician or a doctor (hereinafter simply referred to as an operator) performs a schedule creation process for acquiring a tomographic image. The schedule creation itself is known, but generally, while viewing the display screen, settings such as what range of tomographic images, how many millimeters are to be collected at what intervals, and how many millimeters are to be collected are made. For example, if the liver is to be diagnosed, the setting of the range where the liver is located should be performed using
The slice thickness and the interval are set by the keyboard 57. Here, in the X-ray tomographic image, the part corresponding to the liver is an ROI (Region Of Interest),
For convenience, the range in the Z-axis direction including the portion corresponding to the liver
It is referred to as ROI.

From the relationship between the image displayed on the CRT 56 and the Auto mA table 53a, the CPU 51 reversely calculates the position of the ROI in the Z-axis direction of the table 12 set by the operator.

Now, according to the scan schedule (stored at a predetermined position in the RAM 53) as described above, the main scan (the X-ray tube 4 and the detection unit 8 are rotated around the subject so that the X-ray Main scan for reconstructing an image).

In step S4, it is determined whether or not a scan start instruction has been issued based on an input from the keyboard 57 or the mouse 58.

When the scan is started, as described above, step S is performed in order to perform a scan without a contrast agent.
Schedule created in 5 and Auto mA table 23a
Scan operation is performed in accordance with the contents of (1).

In steps S5, S9, and S11, the scanning process in the gantry apparatus 100 is the same. In step S5, a scanning operation is performed according to the contents of the Auto mA table 23a obtained from the positioning image (scout scan). On the other hand, in steps S9 and S11, as will be described later, the scanning is performed in accordance with the corrected Auto mA table. Therefore, in the following, the Auto mA table obtained from the positioning image is
uto mA table, the contents of the tube current value as the primary Auto m
Called A data, modified tables and data are secondary A
uto mA table, called secondary Auto mA data.

Here, the procedure of the scanning process in the embodiment is shown in FIG. 5 and will be described. Here, the processing in step S5, that is, the scan according to the primary Auto mA table (scan when no contrast agent is injected) will be described.

First, in step S21, the subject is transported by driving the table motor 13 to the start position of the ROI. The start position of the ROI differs depending on the position of the table 12 at that time.

Since the point defining the range of the ROI can be expressed by two points on the Z-axis coordinate, of the two points, the coordinate of the Z-axis in the direction of the head of the subject is R +, and the direction of the foot is R +. -, The scan start position is the table 12 at that time.
Is closer to R + or R- as the start position. For example, when the contrast agent is not injected, the table 12 is moved from the position R + to the R- position to perform the scan, and the next time, for example, a schedule is created to perform the scan 20 seconds after the injection of the contrast agent. Scanning is performed by moving the table in the direction. As a result, the trouble of reciprocating the table 12 for each scan can be saved. Since the transport direction of the table 12 is alternately reversed, the data (tube current value) of the ROI area in the Auto mA table 53a is also taken out in the transport direction of the table 12 (ascending or descending order). Become.

Next, the process proceeds to step S22, at which data (tube current value) of the primary Auto mA table corresponding to the scan start position is extracted along the transport direction of the table 12 determined as described above, and is extracted as a parameter. And sends a scan start command to the gantry apparatus 100. The main controller 1 of the gantry device 100 includes:
In accordance with the command and the parameters, various sub-controllers such as the X-ray tube controller 5 are controlled to perform a scanning operation.

When the scanning process is started, the data collected by the data collecting unit 9 is sent from the gantry device 100. The data is received in step S23, the image is reconstructed, and the X-ray tomographic image is formed. After performing reconstruction processing, CRT5
6 and / or stored in the HDD 54. Hereinafter, the processing from step S23 is repeated until it is determined in step S25 that the ROI has reached the end (when R + is the start position, the R-position has been reached).

Returning to the flowchart of FIG.

In step S5, the primary Auto
When the primary scan based on the mA data is performed, the process proceeds to step S6. Hereinafter, the process in step S6 will be described.

It has already been described that the scan in step S5 according to the contents of the primary Auto mA table is based on the positioning image (scout scan). However,
When acquiring the positioning image, there is a possibility that the body axis of the subject does not match the center line of the table 12 for the above-described reason, and the Auto mA may not be performed with high accuracy.

Therefore, in the present embodiment, utilizing the fact that data of a sufficient number of slices has been obtained by scanning when the contrast medium has not been injected in step S5, the primary auto
The mA is updated to the corrected secondary Auto mA table (however, if the data in the primary Auto mA table is accurate, it is not updated).

This will be described in more detail as follows.

At this point, the HDD 54 stores data for X-ray tomographic images of a plurality of slices in the ROI (X-ray tomographic images when no contrast agent is injected), so that the evaluation value of each tomographic image is calculated. I do. Specifically, as shown in FIG. 6, X-rays of slice 1, slice 2,..., Slice i for each displacement of each Z-axis in the ROI by taking an image according to the primary Auto mA table and reconstructing an image. Reconstruct a tomographic image. If the primary AutomA table has sufficient accuracy, the standard deviations SD1, SD2,... SDi of each slice based on the CT value (described in the background art).
Should all be approximately the same, and they should be approximately equal to the known target standard deviation SDz. The standard deviation is described in detail in JP-A-11-104121.

In other words, the standard deviation SD of each slice
.., SDi and the target standard deviation SDz are calculated, and when the difference exceeds the allowable range, the data in the primary Auto mA table at the Z-axis position exceeding the allowable range is It does not show a normal value.

Therefore, in the embodiment, SDz-SDj
(J = 1, 2,..., I) is calculated, and its absolute value (= | S
Dz−SDj |) exceeds the allowable range ε, the SDz−
The tube current at which SDj = 0 is calculated backward, and the j-th data in the primary Auto mA table is corrected (rewritten).

In this way, this processing is performed for all data (tube current value) in the primary Auto mA table in the ROI, and the primary Auto mA table is updated to the secondary Auto mA table. As a result, higher accuracy Auto mA processing is guaranteed in subsequent scans.

As described above, when the table is updated to the secondary Auto mA table, the process proceeds to step S7, and waits for an instruction to complete the injection of the contrast agent. When the injection of the contrast agent is completed,
The process proceeds to step S8, and waits until the timing set in the previously created schedule is reached. For example, if it is decided to start scanning 20 seconds after injection of the contrast medium, the apparatus waits for 20 seconds.

If it is determined that the timing has come, the process proceeds to step S9, and scanning is started. The scan in this step S9 is performed according to the contents of the secondary Auto mA table as described above, that is, the corrected Aut.
o Scan according to the mA table.

Next, in the same manner as in steps S10 and S11, when the scheduled timing comes, the third scan is performed.

As described above, while the X-ray irradiation amount at each displacement of the subject in the Z-axis direction has been controlled based on the positioning image, according to the present embodiment,
Acquisition of information related to primary Auto mA is the same as before, and by performing processing to correct primary Auto mA based on data obtained during the first main scan, it is important for diagnosis after contrast agent injection The accuracy of scanning can be improved, and the amount of exposure to the subject can be minimized. Further, the diagnosis according to the embodiment is highly reliable.

In the above embodiment, the extraction of the positioning image (scout scan) is completed, and the secondary Au is obtained from the tomographic image obtained in the first main scan (primary scan).
Although the table is updated to the to mA table, the table may be updated again based on data obtained at the time of scanning at the next timing (in the embodiment, scanning after 20 seconds of input of the contrast agent). However, the inventors have verified this point, and as a result, the third and subsequent correction processes are performed after the injection of the contrast agent, and the effect of the image due to the contrast agent appears on the standard deviation SD of each slice, and In the case of mA, it has been found that the correction processing based on the tomographic image obtained in the first main scan is sufficient because the data based on the positioning image is dominant in the amount of X-ray irradiation.

Most of the control of the X-ray CT system in the embodiment is performed on the operation console 200. Since the configuration itself of the operation console 200 can be realized by a general-purpose information processing device (workstation, personal computer, or the like), it is also possible to install software in the device and realize the configuration.

That is, an object of the present invention is to supply a storage medium (or a recording medium) in which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and to provide a computer (a computer) of the system or the apparatus. Alternatively, the present invention can also be realized by a CPU or an MPU) reading and executing a program code stored in a storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. The functions of the above-described embodiments are not only realized by executing the program codes read by the computer,
Based on the instructions of the program code, the operating system (OS) running on the computer performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments. .

[0067]

As described above, according to the present invention, X
The information for automatic X-ray dose control in X-ray CT systems or devices is made more accurate, thereby enabling more reliable diagnosis and minimizing the exposure dose to the subject. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a main configuration diagram of an X-ray CT system according to an embodiment.

FIG. 2 is a diagram illustrating an example of a positioning image of a subject in the embodiment.

FIG. 3 is a diagram showing contents of an Auto mA table in the embodiment.

FIG. 4 is a flowchart of a main process in the embodiment.

FIG. 5 is a flowchart showing the contents of a scan process in FIG. 5;

FIG. 6 is a diagram illustrating a positional relationship between slices in an ROI according to the embodiment.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4C092 AA01 AB02 AB04 AC17 CC10 CC13 CD03 CF35 CF48 DD29 4C093 AA22 AA24 BA17 CA15 CA34 EA12 ED07 EE01 FA15 FA18 FA43 FG04 FG05 FG13 FH04

Claims (6)

[Claims] 1. An X-ray generator comprising an X-ray generator and an X-ray detection array, which are opposed to each other, are rotated to detect an object located between the X-ray generator and the X-ray detector. An X-ray CT system for reconstructing an X-ray tomographic image, comprising: an X-ray fluoroscopic image extracting unit configured to extract an X-ray fluoroscopic image of a subject in a body axis direction in a plurality of directions on a plane orthogonal to the body axis. Based on each X-ray fluoroscopic image extracted by the X-ray fluoroscopic image extraction means, the control value of the X-ray irradiation amount of the X-ray tube at each position in the body axis direction of the subject at each of the positions is determined. Calculating means for calculating; irradiating the subject with X-rays in accordance with each position in the body axis direction and the X-ray irradiation amount calculated by the calculating means; Main scan means for reconstructing a series of X-ray tomographic images of the subject in a range including the diagnostic site of The main scanning means corrects the control value of the X-ray irradiation amount at each position calculated by the calculating means according to the evaluation value based on the series of X-ray tomographic images and the position in the body axis direction. An X-ray CT system comprising: 2. The evaluation value is a standard deviation of each of a series of X-ray tomographic images, and the correcting means causes the standard deviation of the X-ray tomographic image at each position to approximate a preset target standard deviation. The X-ray CT system according to claim 1, wherein the calculated control value of the X-ray irradiation amount is corrected. 3. The X-ray CT system according to claim 1, wherein the control value is a tube current value of the X-ray tube. 4. An X-ray generator provided at an opposing position and an X-ray detector comprising an X-ray detection array are rotated,
An operation console connected to an X-ray CT apparatus for detecting an X-ray dose passing through the subject between the X-ray generator and the X-ray detector by the X-ray detector, wherein a body axis direction of the subject is provided. First instructing means for instructing to extract the X-ray fluoroscopic image in a plurality of directions on a plane orthogonal to the body axis, and transmitted from the X-ray CT apparatus by the instruction of the first instructing means. Based on each X-ray fluoroscopic image, each position of the subject in the body axis direction and the X-ray of the X-ray tube at each position are described.
Calculating means for calculating the control value of the radiation dose; and the body axis direction of the subject at predetermined timings of the passage of time according to the respective positions in the body axis direction and the X-ray dose calculated by the calculating means. And a second instructing unit for instructing a scan to extract a series of X-ray tomographic images in a range including the predetermined diagnostic site, wherein the second instructing unit is configured to perform the scanning with the series of X-ray tomographic images and the body. An operation console including correction means for correcting the control value of the X-ray irradiation amount at each position calculated by the calculation means according to an evaluation value based on an axial position. 5. An X-ray generator provided at an opposing position and an X-ray detector comprising an X-ray detection array are rotated,
A method of controlling an operation console connected to an X-ray CT apparatus that detects an amount of X-ray transmitted through the subject between the X-ray generator and the X-ray detector by the X-ray detector, comprising: A first instruction step for instructing to extract an X-ray fluoroscopic image in the body axis direction in a plurality of directions on a plane orthogonal to the body axis; and the first instruction step transfers the X-ray fluoroscopic image from the X-ray CT apparatus. A calculating step of calculating, based on each of the X-ray fluoroscopic images, each position of the subject in the body axis direction and a control value of the X-ray irradiation amount of the X-ray tube for each of the positions; A series of X-ray tomographic images of a range including a predetermined diagnostic region in the body axis direction of the subject are re-produced at predetermined timings of elapse of time in accordance with the calculated positions in the body axis direction and the X-ray irradiation dose. Second to instruct scan to configure
The second instruction step includes the X-ray irradiation at each position calculated in the calculation step according to the evaluation value based on the series of X-ray tomographic images and the position in the body axis direction. A method for controlling an operation console, comprising a correcting step of correcting a control value of an amount. 6. An X-ray generator provided at an opposing position and an X-ray detector comprising an X-ray detection array are rotated,
A storage medium for storing a program code for an operation console connected to an X-ray CT apparatus for detecting an X-ray amount transmitted through the subject between the X-ray generator and the X-ray detector by the X-ray detector; A program code of a first instruction step for instructing to extract an X-ray fluoroscopic image of the subject in the body axis direction in a plurality of directions on a plane orthogonal to the body axis; and Based on each X-ray fluoroscopic image transferred from the X-ray CT apparatus, each position in the body axis direction of the subject and a control value of the X-ray irradiation amount of the X-ray tube for each position are calculated. A predetermined diagnostic part in the body axis direction of the subject at each predetermined time lapse according to the program code of the calculation step to be performed and each position in the body axis direction and the X-ray irradiation amount calculated in the calculation step. A series of X-ray tomographic images In order to configure, second to indicate the scan
The program code of the second instruction step is calculated in the calculation step according to the series of X-ray tomographic images and the evaluation value based on the position in the body axis direction. A storage medium for storing a program code for an operation console, wherein the program code includes a correction step of correcting the control value of the X-ray irradiation amount at each of the determined positions.