JPH0453538A - X-ray diagnostic apparatus - Google Patents

Abstract

PURPOSE:To promptly set angles and display always precise clinical angles so as to reduce operational loads by detecting the angle of rotation of a holding device to each shaft using detecting means, and finding clinical angles using an expression for computation, and displaying the clinical angles in a display means. CONSTITUTION:An alpha-angle detecting sensor 11, a beta-angle detecting sensor 12, and a gamma-angle detecting sensor 13 detect the angle (a) at which a C arm slides, the angle beta of the main rotation of the C arm, and the angle gamma of rotation of a stanchion (about a Z shaft), respectively. Clinical angles e.g. an RAO/LAO angle theta and a Cr/Cd angle eta are computed, using a computational expression, as functions of the three angles alpha, beta, gamma of rotation detected by the respective detecting sensors 11, 12, and 13. The LAO/RAO angle gamma and the Cr/Cd angle etaboth read out from memory 17 by a CPU 16 are displayed on a digital display panel 19 via an I/O port 18. A clinical angle defined as only one direction of photographing can precisely be obtained and displayed on the angle digitally displaying panel 19.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention converts X-rays transmitted from an X-ray source through a subject into an optical image using an image intensifier, and displays the optical image on a TV. The present invention relates to an X-ray diagnostic device that inputs an image into a camera and displays a fluoroscopic image on a TV monitor.

(Prior Art) In an X-ray diagnostic apparatus, particularly for angiography of a subject, a C-arm type holding device, for example, is generally used. This holding device has an X
A ray tube is arranged at the other end of the C-arm, and an image intensifier (hereinafter referred to as I, I
, abbreviated as . ) is arranged opposite to the X-ray source. In addition to the C-arm, a U-arm type holding device having a U-shape may also be used.

In addition, when performing angiography of a subject, X-ray tubes are installed at both ends of the C-arm of the holding device at the fluoroscopic site (or imaging site) of the subject.1. I.

It is necessary to set the angle appropriately.

During angiography of a subject, the first
axis (X axis 1 body axis indicating head and lower limb direction), 2nd axis (Y
Axis 1 (axis perpendicular to the body axis and indicating the shoulder width direction), 3rd axis (Z axis 1
Z
The angle is set using the axis as a reference and the other two axes. That is, the C-arm of the holding device is set with the C-arm main rotation angle β as the mechanical angle of the device, and Y
The C-arm slide angle α is set around the axis.

On the other hand, in addition to the angles of the holding device, such as the C-arm slide angle α and the C-arm main rotation angle β, there is a clinical angle defined diagnostically. This clinical angle is defined as follows.

θ-LAO/RAO η-CRAN I AL/CAUDAL where LAO,
RAO corresponds to the C-arm main rotation angle β, LAO is the leftward rotation angle, and RAO is the rightward rotation angle. In addition, CRANIAL (hereinafter referred to as Cr) and CAUDAL (hereinafter referred to as Cd) correspond to the C-arm slide angle α, Cr is the rotation angle in the direction of the head, and Cd is the rotation angle in the direction of the lower limbs. is the rotation angle.

When the angle is displayed on the display with the clinical angle and the device angle matching, the C-arm slide angle will be displayed as the clinical angle Cr/Cd angle, and the C-arm main rotation angle will be displayed as the RAO/LAO angle. Is displayed.

On the other hand, recently, in addition to the X-axis and Y-axis, holding devices that perform 3-axis control with rotation around the Z-axis are used to quickly set the angle to the optimal position of the subject, making it easier to track blood vessels, for example. I am now able to get used to it.

FIG. 4 is a schematic configuration diagram showing an example of this type of X-ray diagnostic apparatus. In this X-ray diagnostic apparatus, a holding device 1 includes a C-arm 4 attached to the right side of a tip 3a of a support column 3 attached to a ceiling 2, and an X-ray
The wire tube 5 is arranged, and the X! lj! 1, I, and 6 are arranged so as to face the pipe 45. Also, the top plate 7
The subject 8 placed on the X-ray tube 5 and 1. It is arranged so as to be sandwiched between I and 6. Furthermore, the holding device 1 has a C-arm slide angle α and a C-arm main rotation angle β by a C-arm rotation mechanism (not shown).

The Z-axis rotation angle γ is set.

Here, the two-axis rotation angle γ is set to zero, and the head of the subject 8,
Set on the abdomen. That is, in FIG. 4, the X-ray tube 5,
1.1.6, the C-arm slide angle α1 is the clinical angle Cr/Cd angle, C as shown in Figure 5.
The arm main rotation angle β1 matches the RAO/LAO angle.

(Problem to be Solved by the Invention) However, when rotating around the Z-axis, the Z-axis rotation angle γ is 9
It is set to 0 degrees and is set at the lower limb of the subject 8. That is, in FIG. 4, the X-ray tube 5a.

When the angle is set to the position 1.1.6a, the X-axis for the C-arm slide angle of the device and the Y-axis for the C-arm main rotation angle of the device will also be rotated by 90 degrees.

In other words, since there is one more degree of freedom, C
The arm slide angle α3 no longer matches the clinical angle Cr/Cd angle, and the C-arm main rotation angle β3 no longer matches the RAO/Cd angle.
It no longer matches the LAO angle. For this reason, it is not possible to display an accurate clinical angle on the display, and it takes a considerable amount of time to set the accurate angle, creating an operational burden on the operator.

Therefore, the purpose of the present invention is to be able to quickly set the angle and always display an accurate clinical angle even when the holding device is rotated around three mutually orthogonal axes, thereby shortening examination time and ensuring constant imaging. An object of the present invention is to provide an X-ray diagnostic apparatus that can improve the reproducibility of image data in different directions and reduce the operational burden on an operator.

[Configuration of the Invention (Means for Solving the Problems) The present invention has taken the following measures in order to solve the above problems and achieve the objectives. That is, in the present invention, an X-ray source is disposed at one end, and a light image conversion means for converting X-rays transmitted through the subject from the X-ray source into an optical image is disposed at the other end facing the X-ray source. In the X-ray diagnostic apparatus, the X-ray diagnostic apparatus includes a means for making a holding device rotatable around first to third axes that are orthogonal to each other; The present invention is characterized by comprising means for determining a diagnostically defined clinical angle using a predetermined calculation formula using the rotation angle of each axis detected by the detection means, and displaying the clinical angle on a display means.

(Effects) By taking such measures, the following effects are achieved. The clinical angle, for example the RAO/LAO angle, is calculated by a predetermined formula as a function of the three rotation angles detected by the detection means.

As a result, the clinical angle uniquely defined as the imaging direction can be accurately displayed. As a result, the angle can be set quickly, thereby shortening the inspection time, improving the reproducibility of image data in a fixed imaging direction, and reducing the operational burden on the operator.

(Example) Hereinafter, an example of the X-ray diagnostic apparatus according to the present invention will be described. FIG. 1 is a schematic configuration diagram showing an embodiment of an X-ray diagnostic apparatus according to the present invention, and FIG. 2 is a control block diagram for controlling the apparatus shown in FIG. 1.

In FIG. 1, in the X-ray diagnostic apparatus, a holding device 1 includes:
A C-arm 4 is attached to the right side of the tip 3a of the support column 3 attached to the ceiling 2, an X-ray tube 5 is disposed at the lower end of the C-arm 4, and an X-ray tube 5 is disposed at the upper end facing the X-ray tube 45. <1.1.6 is arranged. A subject 8 placed on the top plate 7 is placed between the X-ray tubes 5 and I, 1.6. The holding device 1 is configured to have an arm slide angle α, a C-arm main rotation angle β, and a Z-axis rotation angle γ. Further, the rotation around the Z axis is performed in the X direction, Y direction, not shown provided on the ceiling 2.
This can be done by rotating the support section 3 and a ceiling rail that can run in both directions.

The device also includes a TV left camera (not shown) that converts the optical image outputted from 1.16 into an electrical signal, and a TV monitor (not shown) that displays the transparent image converted into the electrical signal outputted from the TV left camera. We are prepared.

Furthermore, the X-ray diagnostic apparatus is equipped with a device as shown in FIG. The position selection key 26 provides the CPU 16 with angular position data for angularly setting the C-arm 4 to a predetermined imaging position. The C-arm rotation mechanism unit 10 rotates the C-arm 4 about three axes, the X-axis, Y-axis, and Z-axis, which are orthogonal to each other, based on a command signal for instructing the imaging position from the CPU 16, and rotates the C-arm 4 around the three axes that are orthogonal to each other. three angles α at the desired position of
.

Set β and γ. α angle detection sensor 11. β angle detection sensor 12. The γ angle detection sensor 13 is, for example, a potentiometer, and detects the C-arm slide angle α, the C-arm main rotation angle β, and the rotation angle γ of the column (around the Z axis), and calculates these angles α, β, and γ. The signal is supplied to the analog multiplexer 14. The analog multiplexer 14 combines the angles α, β, and γ using a control signal from the CPU 16, which will be described later, and converts these angles α in analog form.

The signals β and γ are supplied to an A/D 15 for converting them into digital signals.

The CPU 16 uses the angles α, β, and γ in digital form output from the A/D 15 to determine the clinical angle, that is, the LAO/RAO angle θ for display.

The Cr/Cd angle η is calculated using the following equation.

LAO/RAO angle θ = arc tan b/ 1- (a2+b2)
・(1) Cr/Cd angle η −arc sin a −(
2) a − sin 2 a + cos
2 a conflict sin 2 β -co
s (7+are tan (sin β/lan
α)1... (3) bm sin 2a+cos 2a ・stn 2
βψ sin (γ+aretan (sjn β/
lanα)1... (4) Fig. 3 is a diagram for explaining the angular force of the LAO/RAO angle θ and the Cr/Cd angle η, and Fig. 3(a) is a perspective view, and Fig. 3(a) is a perspective view. b) is a top view.

When using an approximately 8-bit CPU 16, the memory 17 stores in a table the clinical angle θ and the clinical angle η determined by the above calculation formula for the angles α, β, and γ that can be taken in advance. It is something to keep.

The CPU 16 also controls writing and reading of the clinical angle to the memory 17, and provides the read clinical angle to the I10 port 18 for input/output. The angle digital display panel 19 displays the clinical angles output from the I10 port 18, that is, the LAO/RAO angle θ and Cr/C.
d Angle η is an angle force.

Next, the operation of the apparatus configured as described above will be explained with reference to the drawings. First, the C-arm rotation mechanism section 10
The arm 4 is rotated about three axes, the X-axis, the Y-axis, and the Z-axis, and three angles α, β, and γ are set at desired positions on the subject 8. Then, the α angle detection sensor 11. The β angle detection sensor 12 and the γ angle detection sensor 13 determine the C-arm slide angle α and the C-arm main rotation angle β, respectively.

The Z-axis rotation angle γ is detected, and the angles α, β, and γ are converted into digital signals by the A/D 15 via the analog multiplexer 14.

The LAO/RAO angle θ and Cr/Cd angle η are functions of the angles α, β, and γ output from the angular force D15.
The calculations are performed by the CPU 16 using the calculation formulas shown in formulas (1) to (4) above.

The angular forces of these LAO/RAO angle θ and Cr/Cd angle η will be explained using FIGS. 3(a) and (b). Masu, 3rd
As shown in figure (a), the angle β in the Cr direction is assumed to be 1.
Rotate only. After that, when it is rotated by an angle α in the LAO direction, the horizontal component sin α as shown in Fig. 3(b)
, the vertical component cos α・sin β is obtained, and the amplitude p is sj port 2
α+C082α・sin 2β. Furthermore, when the amplitude p is rotated by an angle γ around the Z axis, the horizontal component a
is the above equation (3), and the vertical component is the above equation (4).

The LAO/RAO angle θ and Cr obtained in this way
/Cd angle η is written into the memory 17 and made into a table.

This eliminates the trouble of calculating the angle θ and angle η for each angle setting.

Furthermore, the CPU 16 reads and compares L from the memory 17.
The AO/RAO angle θ and the Cr/Cd angle η are I1
It is displayed on the digital display panel 19 via the 0 port 18.

In this way, according to this embodiment, clinical angles, for example, RAO/
The LAO angle θ and the Cr/Cd angle η are the three rotation angles α detected by the angle force detection sensors 11, 12, and 13, respectively.
It is calculated as a function of β and γ using the above calculation formula.

As a result, a clinical angle uniquely defined as the imaging direction can be accurately obtained, and this clinical angle can be displayed on the angle digital display panel 19. As a result, even when the angle γ is set, the direction in which X-rays are being irradiated to the subject 8 is always displayed accurately in the clinical angle, allowing the operator to The shooting direction can be recognized. Thereby, the angle can be set quickly, the inspection time can be shortened, and the operational burden on the operator can be reduced. Furthermore, image data can be obtained any number of times in a fixed imaging direction, that is, the reproducibility of image data can be improved, and the accuracy of diagnosis can be improved.

Note that the present invention is not limited to the embodiments described above. In the embodiments described above, a holding device using a C-arm has been described, but it may be a device using a U-arm, for example, or may have other shapes. Further, in the embodiment described above, the Z-axis rotation angle was set to 90 degrees with the Z-axis as the center, but an angle other than this may be set. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, the clinical angle, for example, the RAO/LAO angle, is calculated by a predetermined calculation formula as a function of the three rotation angles detected by the detection means.

As a result, the clinical angle uniquely defined as the imaging direction can be accurately displayed. As a result, it is possible to provide an X-ray diagnostic apparatus that can quickly set the angle, thereby shortening the examination time, improving the reproducibility of image data in a fixed imaging direction, and reducing the operational burden on the operator.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the X-ray diagnostic apparatus according to the present invention, FIG. 2 is a control block diagram for controlling the apparatus shown in FIG. 1, and FIG. FIG. 4 is a schematic configuration diagram showing an example of a conventional X-ray diagnostic apparatus, and FIG.
Figure 6 is a diagram showing the relationship between the device angle and the clinical angle when the axis rotation angle is zero, and Figure 6 is a diagram showing the relationship between the device angle and the clinical angle when the Z-axis rotation angle is 90 degrees. be. DESCRIPTION OF SYMBOLS 1... C-arm holding device, 2... Ceiling, 3... Strut part, 4... C-arm, 5... X-ray tube, 6... Image intensifier, 7... Top plate, 7a...
- Bed, 8... Subject,... Ceiling, 10... C-arm rotation mechanism section, 11... α angle detection sensor 12
...β angle detection sensor 13...γ angle detection sensor 14...analog multiplexer, 15...
A/D, 16...CPU, 17...Memory, 18.
...I10 port, 19... Angle digital display panel. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] A holding device having an X-ray source disposed at one end and an optical image converting means for converting the X-rays transmitted through the subject from the X-ray source into an optical image at the other end, facing the X-ray source, In an X-ray diagnostic apparatus, the X-ray diagnostic apparatus includes a means for rotating about a first axis to a third axis that are orthogonal to each other, and a detection means for detecting a rotation angle of the holding device with respect to each axis; An X-ray diagnostic apparatus comprising: means for calculating a clinical angle defined diagnostically using a rotation angle of each axis according to a predetermined calculation formula, and displaying the clinical angle on a display means.