JP2003250784A - X-ray imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray imaging apparatus which can be easily moved for an imaging region being determined by the locations of an X-ray tube/X-ray detector in arbitrary direction, and can easily control imaging. <P>SOLUTION: On first to third base sections 4 to 6, a rotating shaft which rotates around a vertical shaft center is respectively provided. First to third driving sections make the first to third base sections 4 to 6 respectively rotate around the vertical shaft center. A control unit respectively controls the first to third driving sections in such a manner that the imaging of a subject may be performed while a C-shaped holding member 3 is moving under a state wherein an inserting angle ϕ, which is an angle formed by the body axis of the subject and the horizontal axis of the C-shaped holding member 3 when seen on a flat surface, is kept uniform. Therefore, the X-ray imaging apparatus can be easily moved in an arbitrary direction for the imaging region which is determined by the locations of the X-ray tube 9/X-ray detector. <P>COPYRIGHT: (C)2003,JPO

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 for detecting X-rays emitted from an X-ray tube to an object, that is, for imaging the object, and more particularly to an X-ray tube and an X-ray detector. The present invention relates to a technique for controlling imaging of a subject by operating a holding member that holds the object.

[0002]

2. Description of the Related Art In an X-ray imaging apparatus fixed on a horizontal plane, for example, a floor surface or a ceiling surface, an X-ray tube and an X-ray detector are held so that various parts of an object can be imaged. In order to allow the X-ray tube to irradiate the subject by inserting the holding member (for example, C-shaped arm) from different angles, the base for fixing the holding member has a shaft that can rotate or move straight. As such a device, for example,
There are devices having a single axis of rotation that rotates about a vertical axis and devices that have two axes of rotation that rotate about a vertical axis respectively.

In the case of a device having a single axis of rotation, for example, as shown in FIG. 9, a base 52 for fixing a C-shaped arm 51.
In order to load / unload the subject M on / from the top plate 54 which has the rotating shaft 53 and which is also the examination table, the rotation of the rotating shaft 53 about the vertical axis causes the C-arm 51 to rotate in the horizontal plane and to be retracted. . This C-shaped arm 51 includes an X-ray tube 55 and an X-ray tube 55.
Hold the line detector 56.

In the case of a device having two rotary shafts, for example, as shown in FIG. 10, a rotary shaft 102 is attached to a first base 101.
And a rotary shaft 105 on a second base 104 for fixing the C-arm 103, respectively. This C-shaped arm 103
Holds an X-ray tube 106 and an X-ray detector 107, which is similar to a device having a single axis of rotation,
It is equipped with 08.

[0005]

However, in the case of a device having these one-axis or two-axis rotating shafts, there are the following problems. That is, in the case of a device having a single rotation axis, the imaging area determined by the positions of the X-ray tube 55 and the X-ray detector 56 may be located only on the circumference of the rotation axis 53. Can not. Further, in the case of this device, as described above, the main purpose is to retract the holding member (for example, the C-shaped arm 51) when the subject M gets on and off the top plate 54. There is no rotation axis on the base side, for example X
A device having a rotation axis on the axis connecting the ray tube and the X-ray detector is also conceivable, but in the case of such a device, only rotation around the imaging region is possible. Therefore, the position of the imaging region cannot be changed unless the top plate is moved. For example, moving the top plate with the catheter for injecting the contrast agent inserted into the subject is considered to be safe for the subject. And not preferable.

In the case of a device having two axes of rotation, 1
Although the degree of freedom in moving the holding member, the X-ray tube, the X-ray detector, and the like increases as compared with the case of the shaft, there are the following problems. That is, the insertion angle of the holding member (for example, the C-shaped arm 103) with respect to the body axis of the subject M, that is, the angle formed by the body axis of the subject M and the horizontal axis of the holding member in the plan view is kept constant. The locus in which the holding member, the X-ray tube, the X-ray detector, and the like can be moved in this state is limited.

[0007] For example, when a plurality of images are taken while moving along the body axis of the subject M, the insertion angle (φ in Fig. 11) is changed as shown in the plan views of Figs. It changes with each shooting. Even when a plurality of times of imaging is performed while moving along the axis perpendicular to the body axis of the subject M in a horizontal plane, as shown in the plan views of FIGS. 11 (a), (d), and (e). , The insertion angle φ changes with each shooting.

If the photographing is performed in a state where the insertion angle φ is different for each photographing, the mechanical rotation angle of the holding member (for example, the C-arm 103) is changed by changing the insertion angle φ.
For example, the angles of the X-ray tube 106 and the X-ray detector 107 with respect to the body axis of the subject M change, and it is necessary to rotate and correct the changed angle. That is, in addition to the above-described two rotating shafts (rotating shafts 102 and 105), the rotating shaft rotates to the X-ray tube 106 side (for example, a collimator that determines the X-ray illumination field) and to the X-ray detector 107 side. Each axis is required, and the above-mentioned correction is performed by operating the X-ray tube 106 and the X-ray detector 107 with these rotation axes. In particular, when performing imaging while rotating around the axis of the body axis of the subject M, the two rotation shafts (rotation shafts 102, 105) on the first and second bases 101, 104 side are used. While operating, in synchronization with this operation, complicated control is required, such as operating two rotating shafts on the X-ray tube 106 side and the X-ray detector 107 side.

Further, the axis line connecting the X-ray tube 106 and the X-ray detector 107 constantly changes with respect to the subject M as the insertion angle φ changes for each radiographing. This causes a problem when performing imaging (transmission) while chasing the tip of the catheter with the catheter inserted. That is, the X-ray tube 106 and the X-ray detector 107
Since the axis line connecting to and from the subject M always fluctuates, the above-mentioned axis of the catheter inserted into the subject M also fluctuates for each imaging, and the monitor displayed by the X-ray detector 107. The catheter sticks out. As a result, it becomes difficult to shoot while chasing the tip of the catheter.

The present invention has been made in view of the above circumstances, and it is possible to easily move an imaging region determined by the positions of the X-ray tube and the X-ray detector in an arbitrary direction, and to facilitate imaging. An object is to provide an X-ray imaging apparatus that can be controlled.

[0011]

The present invention has the following constitution in order to achieve such an object. That is, the invention according to claim 1 is an X-ray tube for irradiating a subject with X-rays, an X-ray detector for detecting X-rays with which the subject is irradiated, the X-ray tube and X-ray detection. A holding member for holding the container, a base member including a first base portion, a second base portion, and a third base portion connecting the holding member, and a base member arranged on the base member. An X-ray imaging apparatus comprising: a drive unit provided and a control unit for controlling the drive unit in the previous period, wherein the drive unit moves the first base portion around a vertical axis with respect to a horizontal plane. , Rotating the second base portion around the vertical axis with respect to the first base portion, and rotating the third base portion around the vertical axis with respect to the second base portion, In a state where the control means maintains a constant insertion angle, which is an angle formed by the body axis of the subject and the horizontal axis of the holding member when seen in a plan view, Moving the support member, so as to perform imaging of the object, it is characterized in that for controlling the drive means.

[Operation / Effect] According to the invention as set forth in claim 1, the driving means has the first base part around the vertical axis with respect to the horizontal plane and the first base part with respect to the horizontal plane. The second base part is rotated about the vertical axis, and the third base part is rotated about the vertical axis with respect to the second base part, while the insertion angle is kept constant. Since the control means controls the driving means so as to move the holding member connected to the base part and image the subject, for example, an X-ray tube or an X-ray detector with respect to the body axis of the subject. It is possible to easily move the imaging area determined by the positions of the X-ray tube and the X-ray detector without performing complicated control for correcting the angle changed for each imaging. In addition, the trajectory for moving the holding member, the X-ray tube, the X-ray detector, and the like is not limited, and can be moved in any direction.

Further, the invention according to claim 2 is such that an X-ray tube for irradiating the subject with X-rays, an X-ray detector for detecting the X-rays with which the subject is irradiated, the X-ray tube, and A holding member for holding the X-ray detector, a first base portion, a second base portion,
And a base member composed of a third base portion that connects the holding member, a drive unit disposed on the base member, and a control unit that controls the drive unit in the previous period.
In the radiographic apparatus, the drive means may be configured such that the first base portion is arranged around a vertical axis with respect to a horizontal plane and the second base portion is arranged vertically with respect to the first base portion. Around the second base portion, the third base portion is rotated about the vertical axis, and the control means does not move the axis connecting the X-ray tube and the X-ray detector. The driving means is controlled so as to change the insertion angle, which is the angle formed by the body axis of the subject and the horizontal axis of the holding member when seen in a plan view.

[Operation / Effect] According to the invention described in claim 2, the driving means has the first base portion around the vertical axis with respect to the horizontal plane and the first base portion with respect to the horizontal plane. The second base part is rotated about the vertical axis, and the third base part is rotated about the vertical axis with respect to the second base part, so that the axis connecting the X-ray tube and the X-ray detector is formed. Since the control means controls the driving means so as to change the insertion angle without moving, for example, in the case of performing imaging (fluoroscopy) while chasing the tip of the catheter with a contrast agent injection catheter inserted. In addition, the axis can be fixed to the catheter while changing the insertion angle, and the same part of the subject can be imaged while changing the insertion angle while the axis is fixed to the subject. , The shooting can be easily controlled.

In addition to the above X-ray imaging apparatus, the present specification also discloses an invention relating to the following X-ray imaging apparatus and a control method used for the X-ray imaging apparatus.

(A) In the X-ray imaging apparatus according to claim 1, the angle by which the first base portion rotates about the vertical axis is α, and the second base portion is about the vertical axis. The rotation angle is β, the rotation angle of the third base portion about the vertical axis is γ, and the rotation angle of the first base portion about the vertical axis is the second axis. The distance between the rotating shafts around which the pedestal rotates about the vertical axis is 1, and the rotation axis around which the second base portion rotates around the vertical axis and the third base portion rotates around the vertical axis. The distance between the rotating shafts is m, and the distance between the axis connecting the X-ray tube and the X-ray detector of the rotating shaft / holding member where the base of the third base rotates about the vertical axis. n is the sum of α, β and γ, φ is α + β + γ, the body axis direction of the subject is x, the direction perpendicular to the body axis in the horizontal plane is y, and a is x-cos φ, b , And y-sin φ, with α kept constant, α, β,
γ is α = sin ⁻¹ [{x−n · sin φ−m · sin
(Sin ^-1 [{a ² + b ² + m ² -l ² } / {2m · (a ²
+ B ² ) ^1/2 }]-tan ^-1 [{yn-sin φ} /
{X−n · cos φ}])} / l], β = (sin
^-1 [{a ² + b ² + m ² -l ² } / {2m · (a ² + b ² )]
^1/2 }]-tan ^-1 [{y-n · cos φ} / {x-n
.Sin .phi.}])-. Alpha.,. Gamma. =. Phi .-. Alpha .-. Beta. Is satisfied, and the control means controls the driving means so as to rotate .alpha., .Beta., And .gamma., Respectively.

[Operation / Effect] According to the above invention, α + β + γ which is the sum of α, β and γ becomes φ, and this φ becomes the insertion angle. Since φ is kept in a constant state, the control means controls the driving means so as to rotate α, β, and γ while satisfying such an expression, so that the insertion angle is kept constant. In this state, the holding member can be moved to image the subject.

(B) In the X-ray imaging apparatus according to claim 2, an angle at which the first base portion rotates about the vertical axis is α, and the second base portion is about the vertical axis. The rotation angle is β, the rotation angle of the third base portion about the vertical axis is γ, and the rotation angle of the first base portion about the vertical axis is the second axis. The distance between the rotating shafts around which the pedestal rotates about the vertical axis is 1, and the rotation axis around which the second base portion rotates around the vertical axis and the third base portion rotates around the vertical axis. The distance between the rotating shafts is m, and the distance between the axis connecting the X-ray tube and the X-ray detector of the rotating shaft / holding member where the base of the third base rotates about the vertical axis. n is the sum of α, β and γ, φ is α + β + γ, the body axis direction of the subject is x, the direction perpendicular to the body axis in the horizontal plane is y, and a is x-cos φ, b Is defined as y-sin φ, α, β and γ are α = sin ⁻¹ [{x−n · sin
φ−m · sin (sin ⁻¹ [{a ² + b ² + m ² −l ² } /
{2m · (a ² + b ² ) ^1/2 }]-tan ⁻¹ [{y−n ·
sin φ} / {x−n · cos φ}])} / l], β =
(Sin ^-1 [{a ² + b ² + m ² -l ² } / {2m · (a ²
+ B ² ) ^1/2 }]-tan ^-1 [{yn-cosφ} /
{X−n · sin φ}]) − α, γ = φ−α−β while the control means controls the driving means so as to rotate α, β, γ respectively. apparatus.

[Operation / Effect] According to the above invention, α + β + γ, which is the sum of α, β, and γ, becomes φ, and this φ becomes the insertion angle. Since x and y are both kept constant, the control means controls the drive means so as to rotate α, β, γ while satisfying such an expression, thereby controlling the X-ray tube and the X-ray. The insertion angle can be changed without moving the axis connecting the detector.

(1) A control method used in the X-ray imaging apparatus according to claim 1, wherein the body axis of the object and the X-ray tube when viewed in plan during X-ray imaging of the object A control method characterized in that an imaging of a subject is controlled by moving a holding member while keeping a constant insertion angle, which is an angle formed by a horizontal axis of a holding member holding an X-ray detector.

[Operation / Effect] According to the above-mentioned invention, the holding member is moved in a state where the insertion angle is kept constant, and the subject is controlled to be imaged. It is not necessary to perform complicated control for the X-ray tube or the X-ray detector with respect to the body axis to perform correction for the angle changed for each imaging. As a result, the imaging area determined by the positions of the X-ray tube and the X-ray detector can be easily moved.

(2) A control method used for an X-ray imaging apparatus, wherein the apparatus detects an X-ray tube that irradiates the subject with X-rays, and an X-ray that detects the X-rays that the subject is irradiated with. A detector, a holding member that holds the X-ray tube and the X-ray detector, a first base portion, a second base portion, and a third base portion that connects the holding members. A base member, a drive means arranged on the base member, and a control means for controlling the drive means, wherein the drive means connects the first base portion to a vertical axis with respect to a horizontal plane. Around the center, the second base portion with respect to the first base portion about the vertical axis, and the third base portion with respect to the second base portion about the vertical axis. When rotating, it is possible to change the insertion angle, which is the angle formed by the body axis of the subject and the horizontal axis of the holding member in plan view. Control method for the butterflies.

(3) In the control method according to (2), when the device and the subject are likely to interfere with each other, the insertion angle is changed so that the device and the subject do not interfere with each other. Characteristic control method.

[Operation / Effect] According to the invention of (2), the insertion angle is changed. The change of the insertion angle may be performed during photographing, before photographing, or after photographing. Further, according to the invention of the above (3), when there is a possibility that the device (for example, the holding member) and the subject interfere with each other, the insertion angle is changed so that the device and the subject do not interfere with each other. The entire subject can be imaged in the operating range.

(4) In the control method according to (2) or (3), the insertion angle is changed so that the axis connecting the X-ray tube and the X-ray detector does not come off the subject. Characteristic control method.

[Operation / Effect] According to the above invention, the entire subject can be continuously imaged while the insertion angle is being changed, without leaving the subject. The fact that the axis line does not deviate from the subject means that the region of the subject does not deviate from the range that can be detected by the X-ray detector. For example, the insertion angle may be changed while fixing only the body axis direction of the subject, or the insertion angle may be changed while fixing only the vertical direction in the horizontal plane with respect to the body axis direction of the subject. You may go. More preferably, shooting is controlled as in (5) below.

That is, (5) the control method described in the above (4), wherein the insertion angle is changed without moving the axis.

[Operation / Effect] According to the invention of (5), since the insertion angle is changed without moving the axis, the insertion angle is changed with the axis fixed to the subject. Is done. Therefore, for example, even when performing imaging (fluoroscopy) while following the tip of the catheter with a catheter for injecting a contrast medium inserted, the axis can be fixed to the catheter while changing the insertion angle. By changing the insertion angle with the axis fixed to the sample, the same region of the subject can be imaged, and the imaging can be easily controlled.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing a schematic configuration of an X-ray imaging apparatus according to this embodiment, and FIG. 2 is a plan view showing an example of an operation mode of the apparatus. In addition, in the present embodiment, the contrast agent is injected into the subject via the catheter for injecting the contrast agent, and the subtraction processing is performed on each of the photographed images before and after the injection, for example, a blood vessel image. An example of a digital subtraction angiography apparatus for capturing an image will be described. As shown in FIG. 1, the apparatus of this embodiment includes a top plate 1 on which a subject M is placed for examination.
It is composed of a base member 2 and a C-shaped holding member 3. C
The mold holding member 3 corresponds to the holding member in the present invention.

The base member 2 is composed of a first base portion 4, a second base portion 5, and a third base portion 6. Also,
The base member 2 has three rotary shafts that rotate around a vertical axis (around the z axis in FIGS. 1 and 2), and the first base portion 4 has a rotary shaft 4 a. The second base portion 5 has a rotary shaft 5a, and the third base portion 6 has a rotary shaft 6a.

The base member 2 includes a first drive section 4A and a second drive section 4A.
The drive unit 5A and the third drive unit 6A are provided. The first drive unit 4A is a floor surface (x, y planes in FIGS. 1 and 2).
On the other hand, the first base portion 4a is rotated about the rotation axis 4, that is, about the vertical axis, and the second drive portion 5A is connected to the first base portion 4a.
On the other hand, the second base portion 5 is arranged around the rotation axis 5a, that is, around the vertical axis, and the third drive portion 6A is arranged so that the second base portion 5 is formed.
On the other hand, the third base portion 6 is rotated about the rotation axis 6a, that is, about the vertical axis. The 1st-3rd drive parts 4A-6A are equivalent to the drive means in this invention.

The first drive section 4A is built in the first base section 4. The first drive unit 4A includes a motor 4b, a belt 4c that transmits the rotation of the motor 4b, a gear box 4d that converts the rotation transmitted to the belt 4c into a rotation around a vertical axis, and a rotary gear 4d. The gear 4e is configured to transmit rotation about the vertical axis and the gear 4f is meshed with the gear 4e. The gear 4f is fixed to the floor with a bearing (not shown) interposed.
The rotation of the motor 4b causes the gear 4f to rotate around the vertical axis through the belt 4c, the gear box 4d, and the gear 4e, and the rotation of the gear 4f causes the first base to move against the floor surface. The part 4 rotates about the vertical axis.

The second drive unit 5A and the third drive unit 6A are also
Similar to the first drive unit 4A, it is composed of a motor, a belt, a gear box, and two gears. In the case of the second and third drive units 5A and 6A, they are built in the second base unit 5.
In the case of the second drive unit 5A, the gear that rotates the second base unit 5 among the two gears is the first base unit with a bearing (not shown) interposed. The second base 5 rotates with respect to the first base 4 by rotating the gear around the vertical axis. In the case of the third drive unit 6A,
Of the two gears, the gear that rotates the third base portion 6 is fixed to the third base portion 6 with a bearing (not shown) interposed, and this gear has a vertical axis. By rotating around, the third base portion 6 rotates about the vertical axis with respect to the second base portion 5.

On the other hand, the C-shaped holding member 3 is composed of a holding table 7, a C-shaped arm 8, and an X-ray tube 9 and an X-ray detector 10 which are respectively supported on both ends of the C-shaped arm 8. First
~ Like the third base parts 4 to 6, the holding base 7 has a rotating shaft 7a.
Have. Unlike the first to third base parts 4 to 6, the rotating shaft 7a is, for example, an axis of the body axis of the subject M (x axis in FIGS. 1 and 2) by a motor (not shown). Rotating around the center, this motor is built in the third base portion 6. That is, the third base portion 6 and the holding base 7 are connected so that the holding base 7 of the C-shaped holding member 3 rotates about the rotation shaft 7a with respect to the third base portion 6. An axis connecting the X-ray detector 9 and the X-ray detector 10 is an axis 11 as shown in FIG.

A holder is provided around the axis of an axis 8a (y-axis in FIGS. 1 and 2) perpendicular to the body axis of the subject M in a horizontal plane (xy plane in FIGS. 1 and 2). The holding base 7 and the C-shaped arm 8 are connected so that the C-shaped arm 8 rotates along the line 7. The C-shaped arm 8 is slid into the arm portion 7b of the holding base 7 and rotated by, for example, a roller or a drive belt (not shown).

A control unit 12 for integrally controlling the apparatus of this embodiment is provided, and the control unit 12 moves, for example, the top plate 1 or controls the first to third drive units 4A to 6A. Is configured to. The control unit 12 corresponds to the control means in the present invention.

When the insertion angle of the C-shaped holding member 3 with respect to the body axis of the subject M is φ (see FIGS. 5 and 6),
The first to third drive units 4A to 6A are controlled by the control unit 12 so that the insertion angle φ is kept constant during photographing or the insertion angle φ is changed without moving the axis 11.
Controlled by. Then, with the insertion angle φ kept constant, or with the insertion angle φ being changed without moving the axis 11, the C-shaped holding member 3 is moved to image the subject M. A specific method of moving the C-shaped holding member 3 to image the subject M while the insertion angle φ is kept constant will be described with reference to the plan view of FIG. 3.

On the xy plane, the rotary shaft 4a of the first base portion 4 is positioned at the origin O (0,0) as shown in FIG. 3, and the first to third base portions 4 to 6 are arranged. Arrange in series on the x-axis. A state in which the first to third base parts 4 to 6 are arranged in series on the x-axis is shown by a dotted line in FIG. Further, the distance between the rotary shaft 4a of the first base portion 4 and the rotary shaft 5a of the second base portion 5 is 1, the rotary shaft 5a of the second base portion 5 and the third base portion are 6, the distance between the rotating shafts 6a of 6 is m, and the rotating shaft 5a of the third base portion 5 is
The distance between the axes 11 connecting the X-ray detector 9 and the X-ray detector 10 of the C-shaped holding member 3 is n.

When the rotary shaft 4a of the first base portion 4 is rotated by the angle α from the state where the first to third base portions 4 to 6 are arranged in series on the x-axis, 2 in FIG. The state shown by the dotted line is obtained. From the state shown by the chain double-dashed line in FIG.
When the rotation shaft 5a of the base part 5 of FIG.
The state shown by the alternate long and short dash line is shown. From the state shown by the one-dot chain line in FIG. 3, the rotation shaft 6a of the third base portion 6
Is rotated by an angle γ, the state shown by the solid line in FIG.

In the state shown by the solid line in FIG.
When the position of the axis 11 is P (x, y) when the third base parts 4 to 6 are arranged, the coordinates of P (x, y) are as shown in the following formulas (1) to (3). Represented by. x = {l · cos α + m · cos (α + β) + n · cos (α + β + γ)} (1) y = {l · sin α + m · sin (α + β) + n · sin (α + β + γ)} (2) φ = α + β + γ ... … (3)

Φ represented by the above equation (3) is also the above-mentioned insertion angle φ. Next, when the clockwise rotation is positive, the velocities in the x and y directions are Vx and Vy, and the rotation axis 4a
When the rotation speeds of 6a are Vα, Vβ, and Vγ, respectively, they are expressed by the following equations (4) and (5).

[0042]

[Equation 1]

When a is x-cos φ and b is y-sin φ, α, β and γ are expressed by the following equations (6) to (8) from these equations.

[0044]

[Equation 2]

In equations (6) to (8), if α, β and γ are rotated so that the insertion angle φ is constant, the insertion angle φ
Is kept constant, the C-shaped holding member 3 is moved,
The subject M can be imaged. Further, when y is constant, as shown in FIGS. 2 (a) to 2 (c) (or FIGS. 2 (d) to 2 (f) or 2 (g) to (i)), the insertion is performed. With the angle φ kept constant (φ is 0 ° in FIG. 2), the C-shaped holding member 3 is arranged along the body axis of the subject M.
Can be moved. Further, when x is constant, for example, FIGS. 2 (a), 2 (d), 2 (g) (or 2 (b), 2 (e), 2 (h), or 2 (c),
As shown in (f) and (i), the C-shaped holding member 3 can be moved along the axis 8a that is perpendicular to the body axis of the subject M in the horizontal plane.

A method of changing the insertion angle φ without moving the axis 11 will be described later in step S4.

Next, after placing the subject M on the top plate 1,
FIG. 4 shows a control method of performing X-ray imaging while moving the C-shaped holding member 3 and lowering the subject M from the top 1.
Will be described with reference to the flow charts of FIGS. 2 and 5, and the plan views of FIGS. In this embodiment, in the vicinity of the head of the subject M, the insertion angle φ is kept at 0 °, that is, the body axis of the subject M and the horizontal axis of the C-shaped holding member 3 in the longitudinal direction are parallel to each other. It is assumed that the imaging is performed in the state of being kept, and the imaging is performed near the groin (groin) of the subject M with the insertion angle φ kept constant at an angle other than 0 °. In the present embodiment, for convenience of explanation, the head of the subject M to the groin area are sequentially imaged.

(Step S1) Placing the Subject on the Top 1 The subject M is placed on the top 1. The top plate 1 is retracted in advance to a position where it does not interfere with the base member 2 and the C-shaped holding member 3. Also, by taking the posture shown in FIG.
The C-shaped holding member 3 can also be retracted. In this case, by controlling the rotation as shown in FIGS. 7A and 7B, or by taking the angles α, β, γ determined by a predetermined posture,
Retraction of the C-shaped holding member 3 can be achieved.

(Step S2) Moving the Top Plate With the subject M placed on the top plate 1, a predetermined portion of the subject M placed on the top plate 1 is a C-shaped arm of the C-shaped holding member 3. The top plate 1 is moved so as to be located on the axis 11 connecting the X-ray tube 9 of 8 and the X-ray detector 10. When the predetermined portion of the subject M is near the head, the first to third drive units 4A to 6A are controlled in advance so that the insertion angle φ becomes 0 °.

(Step S3) X-ray imaging After the top 1 is moved so that the predetermined part of the subject M is located on the axis 11, the movement of the top 1 is stopped and X-ray imaging is started.

When the predetermined portion of the subject M is near the head, X-ray photography is performed with the insertion angle φ kept at 0 °.
Specifically, in order to rotate α, β, γ by substituting φ = 0 in the equations (6) to (8), the first to third drive units 4 are rotated.
Control A-6A. As described above, in this embodiment, images are taken in order from the head to the groin, but when inserting a catheter for injecting a contrast agent from the groin, images are taken in order from the groin to the head. 2 (f)-
C of the C-shaped holding member 3 in the order shown in (e) to (d).
The mold arm 8 takes an image while moving in a horizontal plane. Moreover, when inserting a catheter for injecting a contrast agent from the (left) upper arm, for example, the C-shaped holding member 3 of the C-shaped holding member 3 is arranged in the order shown in FIGS. 2 (b) to (e) to (d). The arm 8 takes an image while moving in a horizontal plane.

It should be noted that while rotating the holding table 7 of the C-shaped holding member 3 with respect to the third base portion 6 about the rotation axis 7a, that is, the C-shaped arm 8, the X-ray tube 9, and the X-ray detector. Imaging may be performed while rotating the holding table 7 around the axis of the body axis of the subject M together with 10, or while rotating the C-shaped arm 8 along the holding table 7 around the axis of the axis 8a. , You may take a picture. Regarding photography by rotation or movement in the horizontal plane, it is possible to take photography by either rotation or movement in the horizontal plane and then by the other, or while performing rotation and movement in the horizontal plane at the same time. You may take a picture. The combination of shooting by these movements is not particularly limited. Further, the photographing may be performed after the movement.

(Step S4) Change of Insertion Angle When the images are taken in order from the head to the groin, the insertion angle φ is 0.
The C-shaped arm 8 of the C-shaped holding member 3 is
When the groin side of the subject M cannot be imaged, that is, the base member 2 and the C-shaped holding member 3
When the top plate 1 and the subject M may interfere with each other (Fig. 2
In (c), (f), and (i), when the top plate 1 may collide with the third base portion 6a of the base member 2, the insertion angle φ is changed and the top plate is changed. After moving 1 to the head side of the subject M, imaging of the groin portion side of the subject M is performed.

There are various methods for changing the insertion angle φ. For example, the insertion angle φ is fixed with the axis 11 connecting the X-ray tube 9 and the X-ray detector 10 fixed to the subject M. change. The operation mode at that time is shown in FIG. The C-shaped arm 8 of the C-shaped holding member 3 moves in the horizontal plane in the order shown in FIGS. 5A to 5C to change the insertion angle φ. Note that the operation mode of FIG. 2F and the operation mode of FIG. 5A are the same, and the operation mode of FIG. 6D and the operation mode of FIG. 5C are the same. Suppose

In order to keep the insertion angle φ constant, α, β, γ were rotated so that the insertion angle φ was constant in the above equations (6) to (8), but the axis 11 was covered. When the insertion angle φ is changed while being fixed to the sample M, x = y = constant value is substituted in the above equations (6) to (8), and α,
The first to third drive units 4A to 4A to rotate β and γ.
Control 6A.

The axis 11 is set in the body axis direction of the subject M (x
The insertion angle φ may be changed with only the axial direction fixed, or the insertion angle φ may be fixed with only the vertical direction (y-axis direction) in the horizontal plane to the body axis of the subject M fixed. It may be changed, or the insertion angle φ may be changed without fixing the axis 11 to the subject M. As described above, the axis 11 does not need to be fixed to the subject M, but the extent that the axis 11 does not deviate from the subject M, that is, the X-ray detector, for example, at the point of fluoroscopic imaging while following the tip of the catheter. The first to third drive units 4A to 6 are changed so that the insertion angle φ is changed so that the region of the subject M does not deviate from the range that can be detected by 10 (the range of the monitor displayed).
It is preferable to control A.

By changing the insertion angle φ, the base member 2
And when the C-shaped arm 8 of the C-shaped holding member 3 moves to a position where the top plate 1 and the subject M do not interfere with the C-shaped holding member 3 (at the time of FIG. Base part 6a
When the top plate 1 moves to a place where there is no risk of collision, the X-ray imaging of the groin side is started. Although the top plate 1 is not moved in this embodiment, the top plate 1 may be moved at the same time when the insertion angle φ is changed.
The top plate 1 may be moved after the change, or the insertion angle φ may be changed after the top plate 1 is moved.

(Step S5) The X-ray photography C-shaped holding member 3 is, for example, as shown in FIG.
After the movement to the position shown in (d), the movement of the C-shaped holding member 3 is stopped and the X-ray imaging is restarted.

The same photographing as in step S3 is performed except that the photographing angle φ differs in step S3. That is, X-ray imaging is performed with the insertion angle φ kept constant. Specifically, in the above formulas (6) to (8), the insertion angle φ
The first to third drive units 4A to 6A are controlled so that α, β, and γ are rotated so that is constant.

(Step S6) Movement of the Top Plate When a series of X-ray imaging is completed, the subject M is placed on the top plate 1 so as to be retracted to a position where it does not interfere with the base member 2 and the C-shaped holding member 3. The top plate 1 is moved in the state of being placed.
As in step S1, the C-shaped holding member 3 can be retracted by controlling the rotation so as to take the angles α, β, γ determined in FIGS. 7A and 7B or in a predetermined posture. it can.

(Step S7) Lowering of the subject from the top plate When the top plate 1 is moved to the retracted position, the subject M is lowered from the top plate 1.

According to the series of control methods including the stepping on / off of the subject M to / from the top 1 according to steps S1 to S7 described above, the insertion angle φ (0 ° in step S3) is determined in steps S3 and S5. Since the X-ray imaging of the subject M is performed while the C-shaped holding member 3 is moving while being kept constant, the mechanical rotation angle of the C-shaped holding member 3 is changed in each of steps S3 and S5. For example, the angles of the X-ray tube 9 and the X-ray detector 10 with respect to the body axis of the subject M do not change, respectively. Therefore, the X-ray tube 9 for the body axis of the subject M
It is not necessary for the X-ray detector 10 to perform a complicated control for correcting the angle corresponding to each photographing. Of course, between steps S3 and S5, the insertion angle φ is changed in step S4, and the respective insertion angles φ are different. Therefore, the correction for the angle is performed between steps S3 and S5.

Further, in order to prevent the top plate 1 and the subject M from interfering with the base member 2 and the C-shaped holding member 3, the insertion angle φ is changed in step S4 between steps S3 and S5. With respect to the base member 2 and the C-shaped holding member 3, the entire subject can be imaged in a small operation range. Similarly, in step S4, since the insertion angle φ is changed so as to fix the axis 11 to the subject M, the insertion angle φ is changed while the axis 11 is fixed to the subject M. During this step S4, the axis line 11 does not come off from the subject M. Therefore, for example, even when performing imaging (transmission) while following the tip of the catheter with the catheter inserted, the axis 11 can be fixed to the catheter while changing the insertion angle φ.

Further, according to the apparatus of this embodiment, the first to the third
On the base parts 4 to 7 of the rotary shaft 4a that rotates around the vertical axis.
6a, respectively, and the control unit 12 controls the first to third drive units 4A so that the subject M is imaged while the C-shaped holding member 3 moves while keeping the insertion angle φ constant. ~ 6A
Since, for example, the X-ray tube 9 and the X-ray detector 10 with respect to the body axis of the subject M are changed for each imaging, as in a device having only two axes that rotate around the vertical axis, respectively. The imaging area determined by the positions of the X-ray tube 9 and the X-ray detector 10 can be easily moved without performing complicated control for correcting the angle. Further, like a device having only one axis of rotation about the vertical axis, the C-shaped holding member 3, the X-ray tube 9, the X-ray detector 1
There is no limitation on the locus of movement of 0 or the like, and the movement can be made in any direction.

Further, α + β + γ which is the sum of α, β and γ
Becomes φ, and this φ becomes the insertion angle. In steps S3 and S5, since φ is kept constant,
The first to third drive units 4A to 6A are rotated so that α, β, and γ are rotated while satisfying the expressions (6) to (8).
By controlling each of them, the subject M can be imaged while the C-shaped holding member 3 moves while the insertion angle φ is kept constant. Further, in step S4, since x and y are both kept constant, the first to the first so as to rotate α, β, γ while satisfying the above equations (6) to (8). By controlling each of the drive units 4A to 6A of 3, it is possible to perform imaging without changing the axis 11 from the subject M while changing the insertion angle φ.

The present invention is not limited to the above embodiment, but can be modified as follows.

(1) Although the apparatus of this embodiment described above is a digital subtraction angiography apparatus, the present invention can also be applied to other X-ray imaging apparatuses such as X-ray CT apparatus. In particular, the present invention is useful for an apparatus that performs imaging while rotating around the axis of the body axis of the subject.

(2) In the apparatus of this embodiment described above, the rotary shaft 4a of the first base portion 4 is fixed to the floor surface. However, for example, as shown in FIG. 8, the rotary shaft 4a is fixed to the ceiling surface. It may be fixed to.

(3) In this embodiment described above, step S
Although the top plate was not moved as described above during the X-ray imaging in S3 or S5 or the change of the insertion angle in step S4, the top plate is moved within a range considering the safety of the subject. Good. In this case, X-ray imaging can be performed on a wider area of the subject. In addition, the top plate 1 and the subject M do not interfere (collide) with the base member 2 and the C-shaped holding member 3,
If the insertion angle φ is set so that the top plate 1 can be moved to the maximum extent, the photographing area can be made wider.

(4) In this embodiment described above, step S
Although the axis 11 was fixed to the subject when the insertion angle was changed in 4, the insertion angle may be changed to the extent that the axis 11 does not come off the subject as described above. For example, the insertion angle may be changed while the body axis of the subject is fixed only in the x-axis direction, or the insertion angle may be fixed only in the direction perpendicular to the body axis of the subject in the horizontal plane (y-axis direction). The insertion angle may be changed in the closed state. In the former case, the insertion angle is changed along the y-axis direction, and in the latter case, the insertion angle is changed along the x direction.

(5) In the above embodiment, step S
Although the insertion angle is changed in No. 4, the insertion angle may be consistently made constant during a series of photographing without changing the insertion angle.

Similarly, the apparatus of this embodiment has a function of keeping the insertion angle constant, and the insertion angle can be changed without moving the axis connecting the X-ray tube and the X-ray detector with respect to the subject. However, it may have only one of the function of keeping the insertion angle constant and the function of changing the insertion angle without moving the axis with respect to the subject.

(6) In this embodiment described above, the C-shaped holding member 3 having the C-shaped arm 8 is used as the holding member in the present invention, but a member for holding the X-ray tube and the X-ray detector. If it is, it will not be specifically limited.

[0074]

As is apparent from the above description, according to the present invention, the first to third base portions are rotated about the vertical axis, respectively, and the insertion angle is kept constant. The control means controls the drive means so as to move the holding member connected to the base portion of No. 3 and image the subject (claim 1).
Therefore, the imaging region determined by the positions of the X-ray tube and the X-ray detector can be easily moved in any direction. Further, the control means is driven so that the first to third base parts are respectively rotated around the vertical axis and the insertion angle is changed without moving the axis connecting the X-ray tube and the X-ray detector. Since the means is controlled (the invention according to claim 2), the photographing can be easily controlled.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic configuration of an X-ray imaging apparatus according to this embodiment.

2A to 2I are plan views showing an example of an operation mode in the apparatus of this embodiment.

FIG. 3 is a plan view for explaining a specific method of capturing an image of a subject while the C-shaped holding member moves while the insertion angle is kept constant.

FIG. 4 is a flowchart showing a series of control methods including getting in and out of an object to and from a tabletop.

5A to 5C are plan views showing an example of an operation mode for changing an insertion angle.

6A to 6I are plan views showing an example of an operation mode in the apparatus of the present embodiment.

7 (a) and 7 (b) are plan views showing an example of a retracting mode of the C-shaped holding member according to the apparatus of this embodiment.

FIG. 8 is a side view showing a schematic configuration of an X-ray imaging apparatus according to a modified example.

FIG. 9 is a side view showing a schematic configuration of an X-ray imaging apparatus having a single axis of rotation.

FIG. 10 is a side view showing a schematic configuration of an X-ray imaging apparatus having two axes of rotation.

11 (a) to (e) are X having a two-axis rotation axis.
It is a top view showing an example of the operation mode in a line photography device.

[Explanation of symbols]

2 ... Base member 3 ... C type holding member 4 ... 1st base part 5 ... Second base part 6 ... Third base part 4a, 5a, 6a ... Rotating shaft 4A ... 1st drive part 5A ... Second drive unit 6A ... Third drive unit 8 ... C-type arm 9… X-ray tube 10 ... X-ray detector 11… Axis 12 ... Control unit φ… Insertion angle M ... Subject

Continued front page    (72) Inventor Toru Nakayama             1st Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City Stock Association             Inside the Shimadzu factory (72) Inventor Isao Nakata             1st Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City Stock Association             Inside the Shimadzu factory (72) Inventor Yoshihide Hook             1st Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City Stock Association             Inside the Shimadzu factory (72) Inventor Mitsuru Umeda             1st Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City Stock Association             Inside the Shimadzu factory (72) Inventor, Koji Akutsu             1st Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City Stock Association             Inside the Shimadzu factory F-term (reference) 4C093 AA08 CA16 EC02 EC03 EC16                       EC23 EC28 EC52 EC57

Claims (2)

[Claims] 1. An X-ray tube for irradiating a subject with X-rays, an X-ray detector for detecting the X-rays with which the subject is irradiated, and a holding member for holding the X-ray tube and the X-ray detector. A base member composed of a first base portion, a second base portion, and a third base portion connecting the holding member, and a drive means arranged on the base member. An X-ray imaging apparatus comprising: a control unit for controlling the drive unit, wherein the drive unit includes the first base unit with the first base unit about a vertical axis with respect to a horizontal plane. The second base portion around the vertical axis, and the third base portion around the vertical axis around the second base portion. In a state where the insertion angle, which is an angle formed by the body axis of the subject and the horizontal axis of the holding member when viewed, is held constant, the holding member is moved, An X-ray imaging apparatus, characterized in that the driving means is controlled so as to image the subject. 2. An X-ray tube for irradiating a subject with X-rays, an X-ray detector for detecting the X-rays with which the subject is irradiated, and a holding member for holding the X-ray tube and the X-ray detector. A base member composed of a first base portion, a second base portion, and a third base portion connecting the holding member, and a drive means arranged on the base member. An X-ray imaging apparatus comprising: a control unit for controlling the drive unit, wherein the drive unit includes the first base unit with the first base unit about a vertical axis with respect to a horizontal plane. The second base portion around the vertical axis and the third base portion around the vertical axis relative to the second base portion, and the control means controls X An insertion angle that is an angle formed by the body axis of the subject and the horizontal axis of the holding member when viewed in a plane without moving the axis connecting the X-ray detector and the X-ray detector. An X-ray imaging apparatus, characterized in that the driving means is controlled so as to change.