JP2002010996A - X-ray RADIOGRAPHING DEVICE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically set a radiographing condition corresponding to the physique of a testee body. SOLUTION: This X-ray radiographing device is provided with an X-ray tube 21 and a radiographing stand 10 for housing an X-ray film 11 across the testee body 100 and is a device for exposing the X-ray radiographic image of the testee body 100 made to stand on the radiographing stand 10 to the X-ray film 11. It is provided with a height detection part 30 provided on the radiographing stand 10 capable of detecting the body height L of the testee body 100 at the time of radiographing, a weighing machine 40 provided on the foot of the radiographing stand 10 capable of detecting the body weight W of the testee body 100 at the time of radiographing and a control part 50 for discriminating the physique of the testee body 100 based on the detected body height L and body weight W and changing the exposure energy of the X-ray tube 21 to an appropriate amount corresponding to the discriminated physique.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray imaging apparatus, and more particularly, to an X-ray imaging apparatus having an X-ray tube and an X-ray film accommodating an X-ray film with a subject interposed therebetween. The present invention relates to an X-ray imaging apparatus that exposes a perspective image to an X-ray film.

[0002]

2. Description of the Related Art FIG. 5 is an external perspective view of a conventional X-ray imaging apparatus. In FIG. 5, reference numeral 10 denotes an imaging stand on which a subject 100 stands, 11 denotes an X-ray film, and 12 denotes a film for accommodating an X-ray film 11. Cases, 13a and 13b, support columns for supporting the film case 12 in a vertically slidable manner, 14
Is a base for supporting and supporting the columns 13a and 13b,
20 is an X-ray generator, 21 is the X-ray tube, 22 is the X-ray tube 2
1, a column 23 that supports the case 21 so as to be slidable in the vertical direction, 24 a base (base) that stands and supports the column 23, and 25 an operation unit (X-ray Cable for connecting to a pipe control unit).

At the time of imaging, the subject 100 is
And maintain the required posture. In that case,
If necessary, the imaging site of the subject 100 (chest, abdomen, etc.)
The X-ray tube 21 is moved up / down in accordance with this. In this manner, when the imaging conditions are set, the imaging of the subject 100 (X-ray cone beam XLC
B).

[0004] Generally, at the time of this imaging, the subject 10
Irradiation energy of the X-ray tube 21 is adjusted to always obtain a clear (optimal contrast) X-ray image irrespective of the body type of 0 (obese type, standard type, lean type, etc.). Conventionally, the exposure energy of the X-ray tube 21 has been adjusted based on the subjective judgment of the operator who has observed the body shape of the subject 100 with his eyes.

[0005]

However, if the exposure energy is adjusted based on the subjective judgment (experience, feeling, etc.) of the operator as in the prior art, it takes a long time for the operator to become skilled. In addition, the judgment / adjustment is likely to cause individual differences, and it takes time until the adjustment is completed due to the confusing judgment. Further, if the irradiation energy is set higher than the physique of the subject, it may cause unnecessary excessive exposure to the subject.

An object of the present invention is to provide an X-ray imaging apparatus capable of automatically setting imaging conditions according to the body type of a subject. .

[0007]

The above-mentioned problem is solved, for example, by referring to FIG.
Is solved. That is, the X-ray imaging apparatus of the present invention (1) includes the X-ray tube 21 and the imaging table 10 that accommodates the X-ray film 11 with the object 100 interposed therebetween, and the X-ray of the object 100 that stands on the imaging table 10. X-ray film 11
In the X-ray imaging apparatus, the height detector 30 provided on the imaging table 10 and capable of detecting the height L of the subject 100 at the time of imaging, and provided at the foot of the imaging table 10, The body weight of the subject 100 is determined based on the detected height L and the weight W, and the radiation energy of the X-ray tube 21 is determined according to the determined body weight. And a control unit 50 for changing to an appropriate amount.

According to the present invention (1), the height L and the weight W of the subject 100 standing on the imaging table 10 are automatically detected, so that both the subject and the operator can be detected. No extra work is required. Further, the body type (obesity type, standard type, lean type, etc.) of the subject 100 is determined based on the height L and the weight W of the subject, and the irradiation energy of the X-ray tube 21 is appropriately adjusted according to the determined body type. With this configuration, there is no need to worry about excessively exposing the subject 100, and an X-ray fluoroscopic (X-ray) image with an optimal contrast can always be obtained.

Preferably, in the present invention (2), in the above-mentioned present invention (1), the height detecting section 30 can detect the height H of the film case 12 accommodating the X-ray film 11 and the control section. Numeral 50 designates an imaging part of the subject based on the height L of the subject 100 and the height H of the film case 12, and changes the exposure energy of the X-ray tube 21 according to the determined imaging part. .

For example, when the height H of the film case 12 with respect to the height L of the subject 100 is relatively high, it is possible to determine that the imaging region is the chest, and it is possible to further set an exposure energy suitable for the chest imaging. When the height H of the film case 12 with respect to the height L of the subject 100 is relatively low, it is possible to determine that the imaging region is the abdomen, and it is possible to further set the irradiation energy suitable for abdominal imaging. Therefore, subject 1
An X-ray fluoroscopy (X-ray) image with an optimum contrast is always obtained, depending on not only the body shape of 00 but also its imaging region.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the same reference numerals indicate the same or corresponding parts throughout the drawings.

FIG. 1 is a view showing a configuration of an X-ray imaging apparatus according to an embodiment. In FIG. 1, reference numeral 10 denotes an imaging stand on which a subject 100 stands, 11 denotes an X-ray film, and 12 denotes an X-ray film 11. The film case, 13a and 13b are columns for supporting the film case 12 so as to be slidable in the vertical direction, 14 is a base (base) for vertically supporting the columns 13a and 13b, 20 is an X-ray generator, and 21 is an X-ray tube thereof. , 22 is a case for accommodating the X-ray tube 21, 23 is a column for supporting the case 21 slidably in the vertical direction, 24 is a base (base) for standingly supporting the column 23, and 25 is a console for the X-ray tube 21. (Control unit) It is a cable for connecting to 50.

Further, in the present embodiment, a height detector 30 provided on the imaging table 10 and capable of detecting the height L of the subject 100 and the height H of the film case 12 during imaging, A weight scale 40 provided at the foot (that is, embedded in the step 14) and capable of detecting the weight W of the subject 100 at the time of imaging, the height L and the weight W of the detected subject (further, a film case) 12, the height (H) of the X-ray tube 12 and the control to change the irradiation energy of the X-ray tube 21 to an appropriate amount in accordance with the determined body shape (imaging part). (Operation console) 50.

Further, in the height detecting unit 30, PDs are provided in a row along the height direction of the columns 13a, and a plurality of photodiodes 31 are supported by the columns 13a and 13b so as to be slidable in the vertical direction. With the subject 100
A horizontal bar for measuring the height L by contacting the head of the
ED1 is a light emitting diode attached to one end of the horizontal bar 31, LED2 is a light emitting diode attached to one end of the center line in the height direction of the film case 12, and 32 is the subject 1 according to the light receiving output of a large number of photodiodes PD.
This is a height detection circuit that generates detection information of a height L of 00 and a height H of the film case 12.

In the console 50, reference numeral 51 denotes a CPU for performing main control of the X-ray imaging apparatus; 52, a main memory (MM) including a RAM and a ROM used by the CPU 51; 53, X-ray imaging conditions (tube voltage kV); , Tube current mA, exposure time Sec
Console section (CSL) that can be set manually, etc.)
An interface (IF) 54 connects the CPU 51 to the height detection circuit 32 and the weight scale 40.

FIG. 2 shows a detailed configuration of the height detecting unit according to the embodiment. A vertical groove 35 is provided in the height direction of the column 13a, and the photodiodes PDi, PDk
Are provided at predetermined intervals. The shorter the predetermined interval is, the more accurately the height can be measured.
Since it is only necessary to be able to determine the approximate body shape of 00, for example, 1
cm interval. Therefore, the total number of photodiodes PD can be reduced. In addition, the photodiode PD includes a support 1
It is not necessary to provide it over the entire length of 3a, and in this example, it is provided in a range from around a standard subject's knee (for example, 50 cm) to a maximum height (for example, 210 cm).

On the other hand, a light-emitting diode LED1 is provided at one end of the horizontal bar 31 and a light-emitting diode LED2 is provided at one end of the film case 12, which move together with the slide of the horizontal bar 31 and the film case 12. The sliding operation of these members 31 and 12 can be performed at intervals of, for example, 1 cm.
2 is always located in front of one of the photodiodes PD.

The control signal LE = 1 from the CPU 51
By (ON), only the light-emitting diode LED1 emits light, whereby the height L of the subject 100 can be detected. In addition, only the light-emitting diode LED2 emits light in response to the control signal HE = 1 (ON) from the CPU 51, whereby the height H of the film case 12 can be detected. Therefore, at the time of detecting the height L or the height H, one of the photodiodes PD is turned on. This detection signal is input to an encoder (ENC) of the height detection circuit 32, where an 8-bit binary signal LB0 representing the height L / H is input.
The data is converted into LB7 and further read by the CPU 51 via the interface unit 54. The light emitting diode LE
Instead of D, a laser diode LD may be used.

Returning to FIG. 1, with this configuration, the subject 100 stands on the base 14 and maintains a required posture during imaging. In this case, the horizontal bar 31 is
0, and if necessary, the subject 10
The X-ray tube 21 is moved up / down in accordance with the imaging site (chest, abdomen, etc.)
Let it down. In this way, when the imaging conditions are set, the subject 100
(Irradiation of X-ray cone beam XLCB). Hereinafter, the shooting control according to the present embodiment will be described.

FIG. 3 is a flow chart of the X-ray imaging control according to the embodiment, in which the subject 100 is input to this processing in a state where the subject 100 stands in the posture shown in FIG. In step S11, the light emitting diode LED1 is turned on to detect the height L of the subject 100. In step S12, the weight W of the subject 100 is detected by the weight scale 40. In step S13, the light emitting diode LED2 is turned on to detect the height H of the film case 12. In step S14, the body type (physique) of the subject 100 is estimated (determined) based on the detected height L and weight W.

FIG. 4A shows an example of a body type determination table for determining the body type. In the figure, the horizontal axis is the height L of the subject, and the vertical axis is the weight W. In general, it is known that there is a certain relationship between the height L and the weight W of a person having a standard body shape. For example, a value obtained by subtracting a certain value 110 from the height L is the standard weight W. In the figure, this relationship is represented by a standard body shape curve R. For example, a standard weight of a person with a height of 170 cm is 60 kg, and a standard weight of a person with a height of 180 cm is 70 kg.
It is. In the present embodiment, the predetermined area A surrounding the curve R is a standard body area, the area B with a heavier weight is the obese body area, and the area C lighter than the standard is the lean body area.

In step S14, the body type of the subject is determined using such a table. For example, a subject a has a height L = 180 cm and a weight W = 75 kg, and belongs to the standard body type A. The other subject b has a height L =
It is 160 cm in weight and W = 90 kg, and belongs to obesity type B. Still another subject c has a height L = 190 cm and a weight W = 65 kg, and belongs to the lean body type C.

Returning to FIG. 3, in step S15, the imaging region of the subject 100 is estimated (determined) based on the detected height L and the height H of the film case 12. In general, a person's chest, stomach, abdomen and the like are positioned at predetermined ratios in accordance with their height L. Therefore, the detected height L and the height of the film case 12 set in advance in correspondence with the imaging region. H
By comparing with the above, the imaging region (chest, stomach, abdomen, etc.) of the subject 100 can be estimated. It should be noted that since this imaging part is information that the operator already knows, this information may be input from the console 53 to the CPU 51 in advance. In step S16, when imaging the subject 100, the imaging conditions of the X-ray tube 21 are controlled based on the obtained information on the estimated body type and the imaging region of the subject 100.

FIG. 4B shows the tube voltage-tube current characteristics of the X-ray tube 21. When the filament of the X-ray tube 21 is heated,
A tube current mA flows from the anode to the cathode. At this time, if the DC filament current If is kept constant, at a certain tube voltage kV or more, a substantially constant tube current mA flows regardless of the tube voltage kV as shown in the figure, and this region is called a temperature limited region. Therefore, in the present embodiment, in low-voltage imaging where the tube voltage kV falls below 100 kV, the tube voltage kV
By controlling the irradiation energy of the X-ray tube 21 (ie,
In high-voltage imaging where the tube current (mA) is changed and the tube voltage exceeds 100 kV, the irradiation energy (tube current (mA)) of the X-ray tube 21 is controlled by controlling the filament current (If).
Can be changed.

With this configuration, for example, when the subject 100 is obese type B, an X-ray image with a required contrast is obtained by increasing the exposure energy of the X-ray tube 21 more than usual, and the subject 100 is obese type B In the case of X-ray tube 21
By reducing the exposure energy of the subject 100 more than usual, an X-ray image having a required contrast can be obtained without having to worry about the subject 100 being excessively exposed.

In this case, manual fine adjustment based on the judgment of the operator may be added in addition to the automatic control of the irradiation energy. In addition, the imaging site (chest, stomach,
Exposure energy suitable for imaging each part is further automatically adjusted according to the abdomen and the like.

In the above embodiment, the case where the body type of the subject is classified into three levels has been described. However, the classification may be performed in multiple levels.

The irradiation energy of the X-ray tube 21 is X
The irradiation time Sec of the wire tube 21 may be controlled so as to be substantially changed. For example, when the subject 100 is obese type B, the exposure time Sec is increased to increase the exposure time of the X-ray film 11 than usual, and when the subject 100 is lean type C, the exposure time is longer than usual. Reduce Sec and X
The exposure time of the line film 11 is reduced. According to this method, an X-ray image having a required contrast can be obtained regardless of the body shape of the subject 100.

Although a plurality of embodiments suitable for the present invention have been described, it is to be understood that various changes in the configuration, control, processing, and combinations thereof can be made without departing from the spirit of the present invention. Not even.

[0030]

As described above, according to the present invention, the configuration in which the imaging conditions of the X-ray source are automatically adjusted according to the body type (obese type, standard type, lean type, etc.) of the subject makes it possible to reduce the number of subjects. X-ray fluoroscopy (X-ray) images with the optimal contrast are always obtained without the risk of exposure to radiation.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an X-ray imaging apparatus according to an embodiment.

FIG. 2 is a diagram illustrating a height detection unit according to the embodiment.

FIG. 3 is a flowchart of X-ray imaging control according to the embodiment.

FIG. 4 is an image diagram of X-ray imaging control according to the embodiment.

FIG. 5 is an external perspective view of a conventional X-ray imaging apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Imaging stand 11 X-ray film 12 Film case 13a, 13b Prop 14 Base (base) 20 X-ray generator 21 X-ray tube 22 Case 23 Prop 24 Base (base) 25 Cable 30 Height detector 31 Side bar 32 Height Detection circuit 35 Vertical groove 40 Weight scale 50 Control unit (operation console) LED1, LED2 Light emitting diode PD Photodiode

Claims (2)

[Claims] 1. An X-ray tube having an X-ray tube and an X-ray film for accommodating an X-ray film with a subject interposed therebetween.
In an X-ray imaging apparatus for exposing a fluoroscopic image to an X-ray film, a height detection unit provided on an imaging table and capable of detecting the height of a subject at the time of imaging is provided at a foot of the imaging table, and is provided at the foot of the imaging table. A weight scale capable of detecting the weight of the subject, and determining the body type of the subject based on the detected height and weight, and changing the irradiation energy of the X-ray tube to an appropriate amount according to the determined body shape. An X-ray imaging apparatus comprising: 2. A height detecting section capable of detecting a height of a film case accommodating an X-ray film, and a control section discriminating an imaging part of the subject based on the height of the subject and the height of the film case. The X-ray imaging apparatus according to claim 1, wherein the irradiation energy of the X-ray tube is changed according to the determined imaging part.