JP2006218142A - X-ray photographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray photographic apparatus which takes account of the physical constitution of a subject as detected not only from the body thickness but also from the body fat to set automatically an optimum condition for X-ray photography, allowing an improvement of operation for setting X-ray photographic condition and providence of a high-quality X-ray photographic image captured at the set condition. <P>SOLUTION: The apparatus comprises an X-ray photographic condition setting device 8a for setting an X-ray photographic condition for a subject, which is provided with a database 8a1 for storing a standard X-ray photographic condition, a body thickness correcting part 8a2 for correcting the standard X-ray photographic condition in accordance with the body thickness of the subject, and a body fat correcting part 8a3 for correcting the corrected X-ray photographic condition of the body thickness correcting part 8a2 in accordance with the body fat of the subject, wherein the body thickness and the body fat of the subject are input from a subject's information inputting part 8c, and used to correct the standard X-ray photographic condition in accordance with the body thickness and the body fat at the body thickness correcting part 8a2 and the body fat correcting part 8a3, and thus the X-ray photographic condition is set and used to take the photography. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an X-ray imaging apparatus, and more particularly to an X-ray imaging apparatus including a mechanism capable of setting optimal X-ray imaging conditions in consideration of not only the body thickness of an imaging region of a subject but also the body fat percentage.

The tube voltage (voltage applied between the anode and cathode of the X-ray tube), tube current (current flowing between the anode and cathode of the X-ray tube), and the imaging time, which are the imaging conditions for the X-ray image, are the X-ray of the subject. It must be set so that an optimal image can always be obtained with respect to the line imaging region.
The X-ray imaging conditions can be determined once the subject's site and the extent of X-ray absorption are known, but it is difficult to measure the X-ray absorption at that site every time imaging is performed. It is often set from the body thickness that the examiner's X-ray absorption and body thickness have a certain relationship.
However, this relationship varies depending on the imaging region and the imaging direction of this region. Further, since the X-ray absorption varies among individuals even at the same region, the operator sets the body shape of the subject in consideration.
As described above, whether or not the subject can be photographed under the optimum photographing conditions by adjusting the X-ray dose depends largely on the skill level of the operator as well as the body thickness and body shape of the subject.

For this reason, in order to improve the operability of the operator, in setting the above X-ray imaging conditions, a combination pattern such as imaging region, imaging direction, body thickness, age (differentiation between adults and children) in advance A program shooting function is provided in which a plurality of types are set, and shooting conditions are selected and set from the pattern when necessary.
The X-ray imaging conditions of the program imaging function are set based on the techniques disclosed in Patent Literature 1, Patent Literature 2, and the like and operator know-how.

The X-ray imaging conditions disclosed in Patent Document 1 are set by the operator for each imaging based on the body measurement information of the subject's height, weight, and body thickness. Measurement information, i.e., body information measurement means for measuring the height, weight, and body thickness is provided, and imaging conditions are determined from the body measurement information acquired from the detection means, or the body such as the height, weight, and body thickness When the measurement information is known in advance, this is an X-ray imaging apparatus configured to input this to the X-ray imaging apparatus and determine the X-ray imaging conditions.
Furthermore, the X-ray imaging conditions can be determined based on the predicted body thickness obtained from the body weight and / or height of the subject.

Further, the X-ray imaging conditions disclosed in Patent Document 2 includes a means capable of detecting the height and weight of a patient on the imaging table of the X-ray imaging apparatus, based on the height measurement result and the weight measurement result, The body type of the patient is estimated and classified into a lean type, a standard type, and an obese type, and is set by the operator at every imaging.
Japanese Patent Laid-Open No. 5-15521 Japanese Patent Laid-Open No. 2002-10996

  In the method of determining X-ray imaging conditions based on the body measurement information of the subject's height, weight, and body thickness disclosed in Patent Document 1, even a subject having the same body thickness may have a muscular subject. Since there are examiners, considering that X-ray transmittance is different between fat and muscle, there is no guarantee that optimal imaging conditions can always be set only by the body information mainly of body thickness.

  In addition, the method for determining the X-ray imaging conditions by estimating the body type of the lean type, the standard type, and the obese type from the height and weight of the subject disclosed in Patent Document 2 has the most influence on the X-ray absorption. A certain body thickness is a predicted value to the last, and, similarly to the above-mentioned Patent Document 1, since the difference in X-ray transmittance between fat and muscle when the body thickness is the same is not considered, it is more than the above-mentioned Patent Document 1. Furthermore, it is difficult to set the optimum shooting conditions.

As described above, since the X-ray imaging conditions disclosed in Patent Documents 1 and 2 must be set by the operator every time imaging is performed, the burden on the operator is large and the operability is problematic.
Further, it is not set in consideration of the difference in X-ray transmittance between the fat and muscle.
In particular, recently, as represented by multipurpose fluoroscopy systems and circulatory organ X-ray inspection systems, the diversification and sophistication of diagnosis has progressed, and various functions have been demanded accordingly. It is necessary to set X-ray imaging conditions taking into account body fat.

  The object of the present invention is to automatically set the optimum X-ray imaging conditions in consideration of not only the body thickness of the subject but also the constitution obtained from the body fat percentage, and improve the operability of the X-ray imaging condition setting. An object of the present invention is to provide an X-ray imaging apparatus capable of obtaining a high-quality X-ray imaging image under the set imaging conditions.

The X-ray imaging apparatus of the present invention for solving the above problems is achieved by the following. That is,
X-ray irradiation means for irradiating the subject with X-rays, X-ray detection means for detecting X-rays transmitted through the subject, and X-ray imaging condition setting for setting X-ray imaging conditions of the subject Means, an X-ray dose corresponding to the X-ray imaging condition is emitted from the X-ray irradiation means, and an X-ray high voltage generating means for controlling the X-ray dose, and imaging is controlled corresponding to the X-ray imaging condition An X-ray imaging apparatus including an imaging control unit, the subject information input unit for inputting information on the subject, and at least a reference X-ray imaging condition provided in the X-ray imaging condition setting unit And a body thickness correcting means for correcting the reference X-ray imaging conditions stored in the database with the body thickness of the subject input from the subject information input means. is there.

  The body thickness correcting means further comprises body thickness measuring means for measuring the body thickness of the subject, and the body thickness value measured by the body thickness measuring means is input from the subject information input means and the reference Correct the X-ray imaging conditions.

  In addition to the body thickness correction, the body fat percentage of the subject is input from the subject information input means, and the X-ray imaging conditions corrected by the body thickness correction means are the body fat percentage of the subject. And a body fat percentage measuring means for measuring the body fat percentage of the subject, and a body fat percentage value measured by the body fat percentage measuring means is provided. The X-ray imaging conditions input from the information input unit and corrected by the body thickness correcting unit are corrected.

  The X-ray dose to be corrected by the body thickness correcting means and the body fat percentage correcting means is between the anode and cathode of the X-ray tube of the X-ray irradiation means corresponding to the body thickness value and body fat percentage value of the subject. Is corrected by at least one of the tube voltage, the tube current flowing between the anode and the cathode, and the photographing time.

In this way, the body of the subject input from the subject information input means, the body fat percentage, or the body of the subject measured with the body thickness measuring device and the body fat percentage measuring device in the X-ray imaging apparatus Reference X-ray imaging conditions prepared in advance for thickness and body fat percentage were corrected.
This eliminates the need for the operator to manually set X-ray imaging conditions each time an image is taken, even if the subject's body shape and constitution are different. X-ray imaging conditions can be optimized for patients with high fat content, which reduces the burden on the operator and contributes to improved image quality. Is also effective.

  Further, in the present invention, the reference X-ray imaging conditions stored in the database are based on a plurality of reference X-ray imaging conditions corresponding to the imaging region, imaging direction, age, sex, obesity determined by height and weight, and body thickness. And a means for selecting a reference X-ray imaging condition corresponding to the input information from the subject information input means from among these reference X-ray imaging conditions. Correction was made by thickness correction means and body fat percentage correction means.

  With such a configuration, finer X-ray imaging conditions can be set, and image quality can be improved and exposure can be reduced.

  When the X-ray absorption rate at the imaging region of the subject is known in advance, the reference X-ray imaging conditions may be corrected with this X-ray absorption rate.

  According to the present invention, since the reference X-ray imaging conditions prepared in advance are corrected based on the body thickness and body fat percentage of the subject, even if the body shape and constitution of the subject differ, the operator can perform imaging. There is no need to manually set the X-ray conditions each time, and the X-ray conditions can be optimized for muscular and fat subjects who have the same body thickness but cannot be seen only by appearance. As a result, the burden on the operator is reduced and the image quality is improved, and the X-ray dose is also optimized, so that it is effective in reducing exposure.

A preferred embodiment of an X-ray imaging apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing an overall configuration in which the present invention is applied to an X-ray imaging apparatus.
The X-ray imaging apparatus shown in FIG. 1 includes an imaging table 2 for placing the subject 1 at an imaging position, an X-ray irradiation apparatus 3 for irradiating the subject 1 with X-rays, and the subject 1 The X-ray detection device 4 that is disposed at a position facing the X-ray irradiation device 3 across the screen and attached to the imaging table 2, and control parameters and X-ray imaging conditions for controlling the entire imaging system in FIG. 1 are set. And a control console 7 having a display 5 and a TV monitor 6, and the control console 7 for controlling imaging based on the X-ray imaging conditions and control parameters set on the control console 7. An imaging control device 8 provided, and an X-ray that generates a high voltage corresponding to the imaging conditions output from the imaging control device 8 and applies this to an X-ray tube (not shown) of the X-ray irradiation device 3 The X-ray detection signals detected by the high-voltage device 9 and the X-ray detection device 4 are read to collect image data. An image processing device 10 that obtains desired image data by performing various image processing on the image data, a display control device 11 that converts and controls the image data processed by the image processing device 10 into a display image, and the display control device A display device that displays the X-ray image controlled in display 11 on the television monitor 6 of the control console 7, and the body thickness of the subject 1 is measured, and the measured value 12 is input to the imaging control device 8. A body thickness measuring device 13 that measures the body fat percentage of the subject 1 and inputs the measured value 14 to the imaging control device 8 on the footrest portion and the handrail portion of the imaging table 2 And a body fat percentage measuring device 15.

  The imaging table 2 includes a movement adjustment mechanism for positioning at the imaging site of the subject 1, and is configured so that the posture of the subject can be aligned with the moving means of the X-ray irradiation device 3 described later. Yes.

The X-ray irradiation device 3 is an X-ray tube (not shown) that irradiates the subject 1 with X-rays, and the X-rays emitted from the X-ray tube are wasted to the subject. And a movable X-ray diaphragm device (not shown) that limits the X-ray irradiation range so as not to irradiate.
This X-ray irradiation apparatus is supported by the imaging table 2 or by support means (not shown) supported on the ceiling or floor.
The support means is provided with an operating device (not shown) for moving and adjusting to the imaging position of the subject, and the subject is positioned at a position corresponding to the imaging site set on the control console 7 by the operating device. The X-ray irradiation apparatus 3 can be held at this position by moving the examiner.

  The X-ray detection device 4 detects an X-ray signal transmitted through the subject 1, converts the X-ray into light, and further converts it into an electrical signal and a CCD (charge coupled device; solid state). A configuration example consisting of an imaging device) camera was used, but this is also possible with a two-dimensional flat panel detector that captures X-rays that have passed through the subject on an X-ray film. It may be configured to shoot.

  The control console 7 includes an input device such as a keyboard 5a and a mouse (not shown), a touch panel type display device 5b for displaying X-ray imaging conditions and imaging control parameters, a TV monitor 6 for displaying X-ray images, and various types of imaging. Setting of various imaging control parameters such as setting of X-ray imaging conditions (tube voltage, tube current, imaging time) corresponding to the imaging order and X-ray irradiation device 2 and X-ray detection device 4 at the imaging position And a function of controlling the entire photographing system.

The imaging control device 8 generates an X-ray control signal corresponding to the X-ray imaging conditions set on the control console 7 to control the X-ray high voltage device.
Also, the X-ray irradiation device 3 and the X-ray detection device 4 are held at predetermined positions, the X-ray irradiation field is limited by the X-ray movable aperture device, the start and end of imaging, and the output of X-ray detection signal readout commands are output. Etc. are controlled.

The X-ray high voltage device 9 is configured to flow a current through a filament that is a cathode of the X-ray tube of the X-ray irradiation device 3 to heat the filament to a predetermined temperature, and between the anode and the cathode of the X-ray tube. An apparatus that generates a tube voltage, which is a high DC voltage to be applied, and X-rays are exposed from the X-ray tube by the application of the high voltage.
The X-ray dose is controlled by controlling the current flowing through the filament, which is the cathode of the X-ray tube, and controlling the tube current flowing through the anode and cathode of the X-ray tube, the tube voltage, and the imaging time.

The body thickness measuring device 13 is provided in the vicinity of the X-ray irradiation device 3, and the subject is placed on the imaging table 2 and the imaging region of the subject is positioned. Deployed to measure body thickness.
The body thickness of the imaging region of the subject by the body thickness measuring device 13 is measured by measuring the distance L1 [mm] from the body thickness measuring device 13 to the imaging region using an ultrasonic distance measuring device or a laser distance measuring device. The measurement signal 12 is input to the imaging control device 8, and the difference between the measured value L1 [mm] and the distance L [mm] from the X-ray irradiation device 3 to the imaging table 2 that is known in advance. Body thickness X [mm].

The body fat percentage measuring instrument 15 uses, for example, a measuring instrument based on the impedance method disclosed in Japanese Patent Application Laid-Open No. 11-113872 that calculates a body fat percentage from an electric resistance value by passing a weak current through a subject. As described above, the body fat percentage of the subject is measured by arranging two body fat percentage measuring devices on the footrest portion and the handrail portion of the photographing stand 2, and the measured value 14 is obtained as the photographing control device 8. To enter.
The body fat percentage of the subject may be an average value of the values measured by the two body fat percentage measuring devices, or using a measured value of a body fat percentage measuring device arranged closer to the imaging region. Also good. Alternatively, from the economical point of view, the measured value may be used by arranging it on either the footrest portion or the handrail portion of the photographing stand 2.
FIG. 1 (b) is a view from the top when the subject 1 is placed on his back on the imaging table 2, and the body fat percentage measuring device 12 is the foot of the imaging table 2 as shown in FIG. It is provided in the place part and the handrail part.

FIG. 2 shows a configuration block diagram of the photographing control device 8.
The imaging control device 8 is provided in the control console 7, and controls an X-ray imaging condition setting unit 8a for setting X-ray imaging conditions and various components of the X-ray imaging device by setting various imaging control parameters. Subject information such as imaging control parameter setting unit 8b, output signal from body thickness measuring device 13, body fat percentage measurement 15 and name 1, age 17, gender 18, height 19, weight 20, etc. of subject 1 And an input unit 8c for inputting other information 21.

The imaging condition determination unit 8a stores a database 8a1 that stores X-ray imaging conditions of a reference body thickness in advance for each imaging region and imaging purpose, and the reference X-ray imaging conditions output from the database 8a1. A body thickness correction unit 8a2 that corrects the actual body thickness measured by the thickness measuring device 13, and the X-ray imaging conditions corrected by the body thickness correction unit 8a2 are further measured by the body fat percentage measuring device 15 The body fat percentage correction unit 8a3 corrects the fat percentage.
It is assumed that the reference X-ray imaging conditions stored in the database 8a1 include an adult reference X-ray imaging condition and a child reference X-ray imaging condition.

  Subject information such as the name, age, and sex of the subject input from the input unit 8c is determined based on the input age whether the subject to be imaged is an adult or a child, and the corresponding reference X-rays It is necessary to select the imaging conditions and to add a supplementary information to the captured X-ray image to identify the subject.

  The X-ray imaging conditions and the imaging control parameters set by the imaging control device 8 having such a configuration are displayed on the display 5b of the control console 7.

  The X-ray imaging conditions set by the X-ray imaging condition setting unit 8a are input to the X-ray high voltage apparatus 9, and the soot voltage based on the X-ray imaging conditions is converted to the X-ray tube of the X-ray irradiation apparatus 3. The imaging control parameters set by the imaging control parameter setting unit 8b are input to each component of the X-ray imaging apparatus to prepare for imaging. .

Next, the body thickness correcting unit 8a2 that corrects the reference X-ray imaging conditions output from the database 8a1 with the actual body thickness measured by the body thickness measuring device 13 will be described.
In the body thickness correction unit 8a2, the relationship between the body thickness of the subject, the imaging tube voltage, and the imaging tube current shown in FIG. 3 is stored as a table.
In FIG. 3, the horizontal axis body thickness X “mm” is the reference value of the body thickness of an adult subject having a standard body shape, and the reference tube voltage at this body thickness is Vb “kV”, the reference tube. Assuming that the current is Ib “mA”, when the body thickness measured by the body thickness measuring device 13 is larger than the standard body thickness X “mm”, a large amount of X-dose is required. Any one or both of these are corrected to values higher than the reference tube voltage Vb “kV” and the reference tube current Ib “mA”.
On the other hand, when the body thickness measured by the body thickness measuring instrument 10 is smaller than the standard body thickness X “mm”, it is necessary to reduce the X-ray dose, so either one of the tube voltage and the tube current is required. Alternatively, both are corrected to values lower than the reference tube voltage Vb “kV” and the reference tube current Ib “mA”.
The correction of the X-ray dose due to the difference in body thickness has been described with respect to an example in which the tube voltage and tube current are varied. However, the present invention is not limited to this, and the imaging time, which is one of the X-ray imaging conditions, can be varied. The X-ray dose may be corrected according to the body thickness.
Therefore, the X-ray dose correction based on the difference in body thickness may be performed by changing any one, two, or all of the imaging tube voltage, imaging tube current, and imaging time. In the case of children as well, the reference X-ray imaging conditions are corrected with the measured body thickness.

In this way, the X-ray imaging conditions can be corrected with the actually measured body thickness, but the X-ray transmittance is different between the muscular subject and the fat subject even with the same body thickness. .
Therefore, the body fat percentage correction unit 8a3 performs correction as follows according to the body fat percentage measured by the body fat percentage measuring device 15.

In the body fat percentage correction unit 8a3, the relationship between the body fat percentage, the photographing tube voltage, and the photographing tube current of the subject having the same body thickness shown in FIG. 4 is stored as a table.
In FIG. 4, the horizontal axis represents the body fat percentage “%” of the subject, and the vertical axis represents the photographing tube voltage [kV] and photographing tube current [mA] corresponding to the body fat percentage.
Here, assuming that the body fat percentage of the subject having the reference body thickness is 20 [%], the tube voltage value at that time is Vb [kV], and the tube current value is Ib [mA], the same body thickness For obese subjects with a body fat percentage of 30%, X-ray transmission increases when X-rays are irradiated with the tube voltage of Vb [kV] and the tube current of Ib [mA]. Since the image quality deteriorates, either or both of the tube voltage and the tube current are changed to the tube voltage value (V1), tube current value (I1), and the reference tube voltage Vb “kV” and the tube tube current Ib. Correct to a value lower than either or both of "mA".
On the other hand, X-rays were irradiated to a muscular subject with the same body thickness and body fat percentage of 10% with the tube voltage of Vb [kV] and the tube current of Ib [mA]. Then, the amount of X-ray transmission decreases, and the image quality also deteriorates. Therefore, either or both of the tube voltage and the tube current are changed to the tube voltage value (V2) and the tube current value (I2) as described above. Correction is made to a value higher than the voltage Vb “kV” and the reference tube current Ib “mA”.
The correction of the X-ray dose based on the difference in the body fat percentage has been described with respect to an example in which the tube voltage and tube current are varied. However, the present invention is not limited to this. The X-ray dose may be corrected in accordance with the body fat percentage.
Therefore, the correction of the X-ray dose based on the difference in the body fat percentage may be performed by changing any one, two, or all of the imaging tube voltage, imaging tube current, and imaging time.
Similarly, in the case of children, the standard X-ray imaging conditions are corrected with the measured body fat percentage.

  Next, an operation for performing X-ray imaging by applying the present invention will be described with reference to the flowchart of FIG.

(1) Turn on the X-ray imaging device, start the device, place the subject 1 on the imaging table 2, move the X-ray irradiation device 3, the imaging table 2, or the subject 1 and adjust the imaging site Align to the posture where X-rays are irradiated in the imaging direction.
Subject information of the subject's name 16, age 17, gender 18, height 19, weight 20, and other information 21 is input from the keyboard 5a and stored in the database 8a1 via the input unit 8c of the imaging control device 8. To do.
Further, the body thickness measurement signal 12 and the body fat percentage measurement signal 14 of the subject 1 measured by the body thickness measuring instrument 13 and the body fat percentage measuring instrument 15 are input to the input unit 8c.
On the display section 5b of the control console 7, a screen for selecting an imaging region and an imaging direction is displayed, and the imaging region, an area to be imaged by clicking on the imaging region and a soft switch unit for determining the imaging direction with a mouse (not shown), Select the shooting direction. (Step 101)

(2) It is determined whether it is an adult or a child from the age stored in the database 8a1, and this result and the reference X-ray imaging conditions corresponding to the determined imaging region and imaging direction are read out, and this is read by the body thickness correction unit 8a2. To enter. (Step 102)
(3) The body thickness correction unit 8a2 corrects the reference X-ray imaging conditions with the body thickness value actually measured from the input unit 8c. (Step 103)

(4) The X-ray imaging conditions corrected by the body thickness correction unit 8a2 are input to the body fat percentage correction unit 8a3, and the X-ray imaging conditions are determined by the actually measured body fat percentage values from the input unit 8c. to correct. (Step 104)

(5) Read out imaging parameters required for imaging control other than the X-ray imaging conditions from the database 8a1, and input them to the imaging control parameter setting unit 8b. (Step 105)

(6) The X-ray imaging conditions corrected by the body fat percentage correction unit 8a3 and the imaging control parameters input to the imaging control setting unit 8b are displayed on the display unit 5b of the control console 7 (Step 106). Confirm the X-ray imaging conditions and imaging control parameters.
(Step 107)

(8) If it is necessary to adjust the corrected X-ray imaging conditions and the set imaging control parameters, the imaging tube voltage, imaging tube current, imaging time, etc. are input to the keyboard 5a or mouse (not shown). The adjustment is performed by adjusting means (not shown) provided on the control console 7.
This adjustment is fine. (Step 108)

(9) If there is no need to adjust, the finally determined X-ray imaging conditions are set in the X-ray high voltage apparatus 9 (step 109), and the imaging control parameters are set in the imaging control apparatus 8. (Step 110)

(10) The imaging preparation is completed (step 111), and X-ray imaging is started. (Step 112) (11) X-rays corresponding to the imaging tube voltage, imaging tube current and imaging time output from the X-ray high voltage device 9 are irradiated from the X-ray tube (not shown) of the X-ray irradiation device 3, X-rays transmitted through the subject 1 are detected by the X-ray detector 4 and input to the image processing apparatus 10 to generate X-ray image data. (Step 113)

(12) X-ray imaging ends at the set imaging time (step 114), the display control device 11 controls the display of the generated X-ray image data as an X-ray image, and the X obtained by the display control The line image is displayed on the television monitor 6 provided in the control console 7 as image display means. (Step 115)

In this way, the X-ray imaging apparatus is equipped with a body thickness measuring device and a body fat percentage measuring device, and the actual body thickness data of the subject measured immediately before imaging the reference X-ray imaging conditions prepared in advance. Correction was made with the body fat percentage data.
This eliminates the need for the operator to manually correct the X-ray imaging conditions each time an image is taken, even if the subject's body shape and constitution are different. X-ray imaging conditions can be optimized for patients with high fat content, which reduces the burden on the operator and contributes to improved image quality. Is also effective.

In the above embodiment, an example has been described in which two reference X-ray imaging conditions are adults and children.However, a plurality of reference X-ray imaging conditions are set for each age, sex, obesity level determined by height and weight, etc. It is also possible to prepare and select a corresponding one from these.
In this way, finer X-ray imaging conditions can be set, and further image quality improvement and exposure reduction can be expected.

The present invention is not limited to the X-ray imaging apparatus shown in FIG. 1, and can be applied to any configuration of X-ray imaging apparatus such as a standing imaging apparatus and an X-ray fluoroscopic imaging apparatus having a fluoroscopic function.
In particular, the system can be used by performing X-ray fluoroscopy and imaging by applying the X-ray imaging conditions set with the actually measured body thickness and body fat percentage to the multipurpose fluoroscopy system and circulatory organ X-ray examination system. It becomes one of the factors that can cope with the diversification and sophistication of diagnosis.

In the above embodiment, the example in which the X-ray imaging apparatus is provided with the body thickness measuring device and the body fat percentage measuring device has been described, but the present invention is not limited to this.
The measurement of the body thickness may be a method in which an imaging region of the subject is measured with a ruler or a tape measure, and the body thickness value is input from the keyboard 5a in FIG. 1 to the input unit 8c in FIG.

  Although not shown, if the X-ray absorptivity value of the subject's fat, muscle, organ, etc. is measured with an X-ray CT apparatus or the like and known in advance, this absorptivity value is input to the input unit The optimal X-ray imaging condition may be set by correcting the reference X-ray imaging condition with the X-ray absorption value of the imaging region.

Further, the corrected optimum X-ray imaging conditions are recorded in the database 8a1, and for example, updating of the reference X-ray imaging conditions and a plurality of the reference X-ray imaging conditions according to body thickness and body fat percentage are prepared and selected from these. It is also possible to do so.

Furthermore, the relationship between the body thickness, the body fat percentage, the tube voltage, and the tube current in FIGS. 3 and 4 is not limited to the linear graph shown in FIG. Any relationship graph can be used as long as it can optimally correct the X-ray imaging conditions.
Although illustration is omitted, the same can be said for the imaging time which is one of the X-ray imaging conditions.

  Furthermore, in order to simplify the setting of the X-ray imaging conditions, the operator may determine the X-ray imaging conditions based on the body thickness with the naked eye and correct only by the body fat percentage.

The figure which shows an example of the whole structure of the X-ray imaging apparatus to which this invention is applied. 1 is a configuration block diagram of a photographing control apparatus that is a main part of the present invention. The figure which shows the relationship between the body thickness of the subject provided in the body thickness correction | amendment part of this invention, imaging tube voltage, and imaging tube current. The figure which shows the relationship between the body fat rate of the subject provided in the body fat rate correction | amendment part of this invention, imaging tube voltage, and imaging tube current. The flowchart figure explaining operation | movement of this invention.

Explanation of symbols

  1 subject, 2 imaging table, 3 X-ray irradiation device, 4 X-ray detector, 5 operation unit and display unit, 7 control console, 8 imaging control unit, 8a X-ray imaging condition setting unit, 8a1 database unit, 8a2 Body thickness correction unit, 8a3 Body fat rate correction unit, 8b Imaging control parameter setting unit, 8c input unit, 9 X-ray high voltage device, 13 body thickness measurement device, 15 body fat rate measurement device

Claims (9)

  X-ray irradiation means for irradiating the subject with X-rays, X-ray detection means for detecting X-rays transmitted through the subject, and X-ray imaging condition setting for setting the X-ray imaging conditions of the subject Means, X-ray dose corresponding to the X-ray imaging conditions is emitted from the X-ray irradiation means, X-ray high voltage generating means for controlling the X-ray dose, and imaging is controlled corresponding to the X-ray imaging conditions An X-ray imaging apparatus including an imaging control unit, wherein at least reference X-ray imaging conditions are stored in a subject information input unit that inputs information about the subject and the X-ray imaging condition setting unit And a body thickness correcting means for correcting the reference X-ray imaging conditions stored in the database with the body thickness of the subject input from the subject information input means. X-ray imaging device.   2. The body thickness correcting means according to claim 1, further comprising body thickness measuring means for measuring the body thickness of the subject, and inputting the body thickness value measured by the body thickness measuring means from the subject information input means. An X-ray imaging apparatus characterized in that the reference X-ray imaging conditions are corrected by means.   3. The X-ray imaging condition according to claim 1 or 2, wherein the body fat percentage of the subject is input from the subject information input means, and the body fat percentage is corrected by the body thickness correction means. An X-ray imaging apparatus comprising body fat percentage correction means for correction.   The body fat percentage measuring means for measuring the body fat percentage of the subject according to claim 3 is further provided, and the body fat percentage value measured by the body fat percentage measuring means is input from the subject information input means. An X-ray imaging apparatus, wherein the X-ray imaging conditions corrected by the body thickness correcting means are corrected by the body fat percentage correcting means.   3. The X-ray dose to be corrected by the body thickness correcting means according to claim 1, wherein the X-ray dose corresponding to the body thickness value of the subject is a tube voltage between an anode and a cathode of the X-ray tube of the X-ray irradiation means, An X-ray imaging apparatus, wherein correction is performed by at least one of a tube current flowing between an anode and a cathode and an imaging time.   5. The X-ray dose corrected by the body fat percentage correcting means according to claim 3, wherein the X-ray dose corrected by the body fat percentage correcting means corresponds to a body fat percentage value of the subject. An X-ray imaging apparatus, wherein the correction is made by at least one of a tube current flowing between the anode and the cathode and an imaging time.   2. The reference X-ray imaging condition stored in the database includes a plurality of reference X-ray imaging conditions corresponding to an imaging region and an imaging direction, and the subject information is selected from the reference X-ray imaging conditions. An X-ray imaging apparatus comprising means for selecting a reference X-ray imaging condition corresponding to input information from an input means.   8. The reference X-ray imaging conditions stored in the database further comprise a plurality of reference X-ray imaging conditions corresponding to age, sex, obesity level determined from height and weight, and body thickness. X-ray imaging device.   3. The X-ray imaging condition according to claim 1 or 2, wherein an X-ray absorption rate of the imaging region of the subject is input from the subject information input unit, and the X-ray imaging condition corrected by the body thickness correction unit is X An X-ray imaging apparatus comprising X-ray absorption rate correction means for further correcting with the linear absorption rate.

Images