JP2017169627A - X-ray imaging apparatus alignment adjustment support device, method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology to support X-ray imaging apparatus alignment adjustment capable of reducing a degree of dependence on a skill of an operator.SOLUTION: An alignment adjustment support device 30 includes a transparent image input part 31 for radiating an X-ray output from an X-ray source 11 to six reference points 20 positioned in the coordinate system (X, Y, Z) in a treatment space, and inputting a transparent image 13 projected on an X-ray detector 12, a determination part 32 for determining projective coordinates (u,v) of the six reference points recognized in the coordinate system (u,v) of the transparent image, a derivation part 33 for deriving a projection matrix P for converting spatial coordinates (X,Y,Z) of the six reference points in a spatial coordinate system (X,Y,Z) to corresponding six projective coordinates (u,v), and a calculation part 41 for calculating positional information, etc. on the X-ray source 11 and the X-ray detector 12 in the spatial coordinate system (X,Y,Z) based on the projection matrix P.SELECTED DRAWING: Figure 3

Description

  Embodiments described herein relate generally to an alignment adjustment support technology for an X-ray source and an X-ray detector constituting an X-ray imaging apparatus.

When performing radiotherapy, it is necessary to position the patient so that the isocenter of the treatment space coincides with the affected part. The validity of this patient's positioning accuracy is based on an image reconstructed from a three-dimensional image (DRR: Digitally Reconstructed Radiograph) taken with X-ray CT at the time of treatment planning and an X-ray taken with an X-ray machine immediately before treatment beam irradiation. Evaluation is performed by collating with a fluoroscopic image.
The validity evaluation of this positioning accuracy is based on the premise that the X-ray source and the X-ray detector constituting the X-ray imaging apparatus are installed in the treatment space as designed.
For this reason, when the actual installation position deviates from the design position, alignment adjustment for adjusting the installation positions of the X-ray source and the X-ray detector is performed in order to eliminate this deviation.

As a known technique for performing such alignment adjustment, in an X-ray imaging apparatus having a rotation mechanism (C arm), an X-ray source or X-ray is obtained from a plurality of X-ray fluoroscopic images acquired by changing the rotation position. There is a method for calculating the installation position of the line detector.
For X-ray equipment that does not have such a rotation mechanism, a laser marker and mirror are installed on the X-ray irradiation axis connecting the X-ray source and the X-ray detector, and the reflected light is confirmed. There is a method of adjusting the alignment while doing so.

JP 2009-106644 A International Publication Number WO2013 / 061609

  In the known alignment adjustment technique described above, there are problems that the rotation mechanism of the X-ray source and the X-ray detector becomes an essential component, and the result of the adjustment greatly depends on the skill of the operator.

  Embodiments of the present invention have been made in view of such circumstances, and an object thereof is to provide an alignment adjustment support technology for an X-ray imaging apparatus that can reduce the dependence on the skill of an operator. To do.

  In the alignment support device for an X-ray imaging apparatus according to the embodiment, the X-ray source and the X-ray detector output from the X-ray source to at least six reference points positioned in the coordinate system of the space where the X-ray source and the X-ray detector are installed. A fluoroscopic image input unit that inputs X-rays and projects a fluoroscopic image projected on the X-ray detector; and in the coordinate system of the fluoroscopic image, each region of the six reference points that is recognized A determination unit for determining six projective coordinates representing a region, and a derivation for deriving a projection matrix for coordinate transformation of the spatial coordinates of the six reference points in the spatial coordinate system into the corresponding six projected coordinates And a first calculation unit that calculates position information of the X-ray source in the coordinate system of the space and position information and posture information of the X-ray detector based on the projection matrix. To do.

  The embodiment of the present invention provides an alignment adjustment support technique for an X-ray imaging apparatus that can reduce the dependence on the skill of an operator.

Explanatory drawing of alignment adjustment of the X-ray imaging apparatus applied to embodiment of this invention. The external view which shows the patient and X-ray imaging apparatus which were set to the treatment space. The block diagram which shows the alignment adjustment assistance apparatus of the X-ray imaging apparatus which concerns on embodiment of this invention. Explanatory drawing of the arithmetic expression performed in embodiment. Explanatory drawing of the arithmetic expression which reflects the correction | amendment of the X-ray fluoroscopic image of a reference body, and projection coordinates. Explanatory drawing which sets manually the area | region of the reference point projected on the fluoroscopic image. The flowchart explaining the procedure of the alignment adjustment assistance method of the X-ray imaging apparatus which concerns on embodiment of this invention, and the algorithm of an alignment adjustment assistance program.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIGS. 1 and 3, the alignment adjustment support device 30 of the X-ray imaging apparatus 10 is positioned in the coordinate system (X, Y, Z) of the space where the X-ray source 11 and the X-ray detector 12 are installed. A fluoroscopic image input unit 31 that inputs X-rays output from the X-ray source 11 to the at least six reference points 20 (20 _{1 to} 20 ₆ ) that have been projected and projected onto the X-ray detector 12. And six projected coordinates (u _n , v _n ) representing each area from the _six reference point areas 23 (23 ₁ to 23 ₆ ) recognized in the coordinate system (u, v) of the perspective image. The determination unit 32 for determining n = 1 to 6 and the spatial coordinates (X _n , Y _n , Z) of the six reference points 20 (20 _{1 to} 20 ₆ ) in the spatial coordinate system (X, Y, Z); _{n); n} = _1~6 corresponding six projective coordinates _{(u n, v n);} n = 1~6 coordinate transformation to projection matrix P A deriving unit 33 for deriving the position of the projection matrix coordinate system of space based on P (X, Y, Z) position information of the X-ray source 11 at _{(l x, l y, l} z) as well as X-ray detector 12 information _{(c x, c y, c} z) and orientation information _{(u x, u y, u} z) (v x, v y, v z) (w x, w y, w z) first operation for computing a Part 41.

Furthermore, the alignment adjustment support device 30 is based on the design information 45 of the X-ray source 11 in the spatial coordinate system (X, Y, Z) and its position information (l _x , l _y , l _z ). 11, the second calculation unit 42 that calculates the adjustment amount of 11, the design information 45 of the X-ray detector 12 in the spatial coordinate system (X, Y, Z), its position information (c _x , c _y , c _z ), and orientation information _{(u x, u y, u} z) (v x, v y, v z) (w x, w y, w z) third arithmetic for calculating the adjustment amount of the X-ray detector 12 based on the Part 43.

The alignment adjustment support device 30 further includes a display unit 34 that displays the fluoroscopic image 13 and displays the recognized reference point region 23 (23 ₁ to 23 ₆ ) on the fluoroscopic image 13 in an overlaid manner.
Further, the alignment adjustment support device 30 includes a manual setting unit 35 that performs recognition of the reference point region 23 (23 ₁ to 23 ₆ ) by manual setting.

As shown in FIG. 2, radiation therapy is performed by irradiating a patient 15 fixed to the bed 16 with a treatment beam (not shown) from an irradiation port (not shown).
Here, the treatment beam is radiation that irradiates a diseased tissue such as cancer and kills cells. Examples of such radiation include X-rays, γ-rays, electron beams, proton beams, neutron beams, and heavy particles. Examples include lines.

Prior to the irradiation of the treatment beam, a treatment plan is executed in a place different from the treatment space (X, Y, Z coordinate system).
In this treatment plan, the patient takes the same posture as the posture fixed to the bed 16 and receiving the treatment beam in the treatment space, and uses the X-ray CT (Computed Tomography) or the like to obtain a three-dimensional image (voxel data) inside the body including the affected part. Take an image.
Based on the region of the affected area specified by the voxel data, conditions such as the treatment beam irradiation position, irradiation angle, irradiation range, radiation dose, and number of times are determined.

Further, from a virtual viewpoint corresponding to the position of the X-ray source 11, a reconstructed image (DRR: Digitally Reconstructed Radiograph) is generated by projecting this voxel data on a virtual plane corresponding to the position and orientation of the X-ray detector 12. To do.
Note that the position of the virtual viewpoint and the position and orientation of the virtual plane necessary to generate the reconstructed image (DRR) are based on the design information 45 of the X-ray source 11 and the X-ray detector 12, respectively.
Here, the design information 45 is design information indicating mechanical positions, angles, and the like in the treatment space (X, Y, Z coordinate system) of the X-ray source 11 and the X-ray detector 12 constituting the X-ray imaging apparatus 10. It is.

Then, the treatment space (X, Y) of the bed 16 that fixes the patient 15 so that the position of the affected part set on the voxel data coincides with the isocenter set in the treatment space (X, Y, Z coordinate system). , Position information in the Z coordinate system) is determined.
Here, the isocenter is a reference position in the treatment space (X, Y, Z coordinate system) set so that the irradiation center of the treatment beam is located.

Then, the bed 16 to which the patient 15 is fixed is moved to a determined position in the treatment space (X, Y, Z coordinate system), and is imaged by the X-ray imaging apparatus 10 to obtain an X-ray fluoroscopic image 13b.
The patient 15 is imaged in this treatment space (X, Y, Z coordinate system), and the X-ray fluoroscopic image 13b projected onto the u, v coordinate system and the voxel data are virtually re-entered into the u, v coordinate system at the stage of treatment planning. If it matches with the constructed DRR image, it is confirmed that the position of the affected part of the patient 15 matches the isocenter.
However, the validity of this confirmation is based on the premise that the X-ray source 11 and the X-ray detector 12 are installed according to the design information 45 in the treatment space (X, Y, Z coordinate system). .

  The alignment adjustment support apparatus 30 shown in FIG. 3 shows the actual mounting position and posture of the X-ray source 11 and the X-ray detector 12 constituting the X-ray imaging apparatus 10 in the treatment space (X, Y, Z coordinate system). Recognize. Then, a deviation amount between the actual mounting position and orientation and the design information is obtained, and alignment adjustment of the X-ray source 11 and the X-ray detector 12 for eliminating the deviation amount is supported.

As shown in FIG. 1, in the alignment adjustment, a reference body 21 in which at least six reference points 20 (20 _{1 to} 20 ₆ ) are embedded is arranged at a predetermined position in a treatment space (X, Y, Z coordinate system). It is carried out regularly.
The reference body 21 is disposed, for example, via a jig or the like that is detachably installed at a reference point on the floor surface surrounding the treatment space.
Thus, by arranging the reference body 21, each of the six reference points 20 (20 _{1 to} 20 ₆ ) is accurately located at a desired position in the coordinate system (X, Y, Z) of the space. Will be positioned.

Spatial coordinates (X _n , Y _n , Z _n ) of six reference points in this coordinate system (X, Y, Z); n = 1 to 6 are storage units 37a (FIG. 3) of the alignment adjustment support device 30 Is saved.
The X-ray imaging apparatus 10 radiates the X-ray output from the X-ray source 11 to the reference body 21 arranged in this way, and captures a fluoroscopic image 13 a projected onto the X-ray detector 12.
Here, in the X-ray detector 12, X-ray detection elements are arranged in a two-dimensional array, and the X-rays emitted from the X-ray source 11 are transmitted through the patient 15 or the reference body 21 and reach the respective detection elements. X-ray fluoroscopic images 13a and 13b are formed according to the amount of energy attenuation.
The X-ray source 11 employs an X-ray tube that generates X-rays by colliding electrons with a metal target at a high speed. However, the X-ray source 11 outputs X-ray electromagnetic waves that can pass through while attenuating human tissue. If appropriate.

In the alignment adjustment support apparatus 30 shown in FIG. 3, the fluoroscopic image input unit 31 inputs the fluoroscopic image 13 temporarily stored in an X-ray imaging apparatus, an image server, a medium, a network storage, or the like, and displays the fluoroscopic image 13 on the display unit 34. .
Then, the determination unit 32 inputs the fluoroscopic image 13 and recognizes _six reference point regions 23 (23 ₁ to 23 ₆ ) in the coordinate system (u, v) of the fluoroscopic image shown in FIG. Furthermore, the determination unit 32 determines _six representative projection coordinates (u _n , v _n ); n = 1 to 6 from each of the recognized regions 23 (23 ₁ to 23 ₆ ), and stores them in the storage unit 37a. save.
The projected coordinates (u _n , v _n ) can be determined with the center of gravity of each region 23 as a representative, but the method for determining the representative position is not particularly limited.

These recognized reference point regions 23 (23 ₁ to 23 ₆ ) and the determined projection coordinates (u _n , v _n ); n = 1 to 6 are overwritten and displayed on the fluoroscopic image 13 on the display unit 34. be able to. Thus, by overwriting and displaying on the display unit 34, the user can visually evaluate the validity of the projection coordinates (u _n , v _n ); n = 1 to 6 determined by the determination unit 32. . Examples of information displayed on the display unit 34 include an outline of a reference point for a determined position and a projected position, an image obtained by creating an image of the center of gravity and a projected position, and displaying the difference from the image.
Note that the display unit 34 is not an indispensable component, and can be omitted if visual evaluation by the user is unnecessary.

The deriving unit 33 converts the spatial coordinates (X _n , Y _n , Z _n ) of six reference points in the spatial coordinate system (X, Y, Z); n = 1 to 6 into the corresponding six projected coordinates ( u _n , v _n ); A projection matrix P for coordinate transformation to n = 1 to 6 is derived.

The projection matrix P will be described with reference to FIG.
The relationship between the coordinate system (X, Y, Z) of the treatment space and the coordinate system (u, v) of the fluoroscopic image (X-ray detector 12) can be expressed by Expression (1). Here, λ is an arbitrary real number, and P is a 3 × 4 projection matrix.
If this projection matrix P can be obtained, the translational position of the X-ray source 11 in the coordinate system (X, Y, Z) and the translational position and rotational orientation of the X-ray detector 12 are calculated. be able to.

Here, with the position of the X-ray source 11 as the origin, the x-axis and y-axis that are aligned with the u-axis and the v-axis of the X-ray detector 12, and z that is aligned with the direction of the outer product of this x × y A camera coordinate system (x, y, z) defined from the axis is set.
Here, the relationship between the camera coordinate system (x, y, z) and the coordinate system (u, v) of the fluoroscopic image (X-ray detector 12) can be expressed by equation (2). Here, λ is an arbitrary real number, s _u and s _v are pixel pitches in the u-axis and v-axis directions of the X-ray detector 12, and f is a distance from the X-ray source 11 to the X-ray detector 12, respectively. .

Furthermore, the relationship between the camera coordinate system (x, y, z) and the coordinate system (X, Y, Z) of the treatment space can be expressed by equation (3). Here, (u _x , u _y , u _z ) represents the x-axis basis vector of the camera coordinate system, (v _x , v _y , v _z ) represents the y-axis basis vector of the camera coordinate system, ( w _x , w _y , w _z ) represents the basis vector of the z axis of the camera coordinate system, and (l _x , l _y , l _z ) represents the X-ray source 11 in the treatment space coordinate system (X, Y, Z). Represents the position.
From the relationship between Equation (2) and Equation (3), the relationship between the coordinate system (X, Y, Z) of the treatment space and the coordinate system (u, v) of the X-ray detector is expressed by Equation (4). The

Calculating the portion corresponding to the projection matrix P of among Formula (1) in the equation (4), basis vectors in the x-axis of the camera coordinate system, y-axis (u-axis of the X-ray detector, v-axis) (u _x , u _y , u _z ) (v _x , v _y , v _z ) and the z-axis basis vector (w _x , w _y , w _z ) and the position of the X-ray source (l _x , l _y , l _z ) Calculated.
Furthermore, the position (c _x , c _y , c _z ) of the X-ray detector can be calculated from the equation (5). Here, w represents the number of pixels on the u-axis of the X-ray detector, and h represents the number of pixels on the v-axis.
Thus, if the projection matrix P is obtained, the translational position of the X-ray source 11 in the coordinate system (X, Y, Z), the translational position of the X-ray detector 12 and the orientation in the rotational direction are calculated. can do.

Here, the unknowns of the projection matrix P are six reference point spatial coordinates (X _n , Y _n , Z _n ) known in the treatment space coordinate system (X, Y, Z); n = 1-6 And the six projected coordinates (u _n , v _n ) on the X-ray detector 12 on which they are projected; n = 1 to 6.
The projection matrix P defined by equation (1) can be further defined as in equation (6), and further the relationship of equation (7) is established. A projection matrix P is obtained from this equation (7).
In the above description, the coordinate system such as the treatment space is described as an orthogonal coordinate system, but these coordinate systems are not limited to the orthogonal coordinate system.

The first calculation unit 41 includes an X-ray source position calculation unit 41a, an X-ray detector position calculation unit 41b, and an X-ray detector attitude calculation unit 41c.
The X-ray source position calculation unit 41a calculates position information (l _x , l _y , l _z ) of the X-ray source 11 in the spatial coordinate system (X, Y, Z) based on the projection matrix P, and stores the storage unit 37b. Save to.
The X-ray detector position calculation unit 41b calculates the position information (c _x , c _y , c _z ) of the X-ray detector 12 in the spatial coordinate system (X, Y, Z) based on the projection matrix P and stores it therein. Save to 37b.
X-ray detector position calculating unit 41c store, posture information _{(u x, u y, u} z) (v x, v y, v z) (w x, w y, w z) of the calculated storage unit 37b the To do.

The second calculation unit 42 is based on the design information 45 of the X-ray source 11 and its position information (l _x , l _y , l _z ) in the spatial coordinate system (X, Y, Z). The adjustment amount (deviation amount) is calculated.
Then, the alignment adjustment of the X-ray source 11 is performed based on the adjustment amount calculated by the second calculation unit 42.
The third calculation unit 43 includes design information 45 of the X-ray detector 12 in the spatial coordinate system (X, Y, Z), position information (c _x , c _y , c _z ), and posture information (u _x , u). The adjustment amount (deviation amount) of the X-ray detector 12 is calculated based on _y , u _z ) (v _x , v _y , v _z ) (w _x , w _y , w _z ).
Then, the alignment adjustment of the X-ray detector 12 is performed based on the adjustment amount calculated by the third calculation unit 43.

FIG. 6 shows an X-ray fluoroscopic image 13 a displayed overlaid on the display unit 34, and six reference point regions 23 (23 ₁ to 23 ₆ ) automatically recognized by the determination unit 32. ing.
Thus, in the automatic function, it may be necessary to correct the recognition range of the reference point region 23 (23 ₁ to 23 ₆ ).
The manual setting unit 35 manually sets the recognition of the reference point region 23 (23 ₁ to 23 ₆ ) via the input unit 36. Then, from the manually set region 23 (23 ₁ to 23 ₆ ), six projection coordinates (u _n , v _n ); n = 1 to 6 are calculated.

Although it is possible to obtain the projection matrix P from Equation (7) using the manually corrected projection coordinates (u _n , v _n ) of the reference point, the projection calculated from the corrected reference point coordinates and the projection matrix Coordinates may be shifted.
For example, when the position of the projected coordinates (u ₁ , v ₁ ) of the corrected reference point is positive, Equation (8) is established. Further, parameters p of the projection matrix other than p ₁₄ and p _{24 in} Expression (7) are obtained by Expression (9). Using the parameter p obtained by the equation (9), p ₁₄ and p ₂₄ are calculated from the equation (8).
As a result, the projection coordinates of the reference point are corrected, and the accurate position information (l _x , l _y , l _z ) of the X-ray source 11 and position information (c _x , c _y , c _z ) of the X-ray detector 12 are corrected. ) And posture information (u _x , u _y , u _z ) (v _x , v _y , v _z ) (w _x , w _y , w _z ).
The above is a case where one corrected reference point is positive, but a plurality of reference points are also possible.

Note that the display unit 34 and the manual setting unit 35 in the alignment adjustment support device 30 are not indispensable constituent elements, as long as the accuracy of determining the projection coordinates (u ₁ , v ₁ ) of the reference point is sufficiently guaranteed. Can be omitted.
In the present embodiment, a pair of X-ray imaging devices 10 is illustrated as being fixed to a spatial coordinate system (X, Y, Z), but a plurality of pairs of X-ray imaging devices 10 are installed. The present invention can also be applied to a case where the center is rotated or the isocenter is centered.

Next, based on the flowchart of FIG. 7, a series of processes of radiation therapy, a procedure of an alignment adjustment support method included in this process, and an algorithm of an alignment adjustment support program will be described.
In this flowchart, for convenience of explanation, the treatment planning stage (S11 to S13), the alignment adjustment stage (S14 to S20), and the beam irradiation treatment stage (S22 to S26) are shown continuously. This stage is an independent work process.
When the alignment adjustment operation is performed periodically, the alignment adjustment step may be performed prior to the treatment planning step or may be omitted in a series of patient treatment steps.

First, at the stage of the treatment plan, the patient 15 fixed to the bed 16 is subjected to an X-ray CT apparatus or the like to take a three-dimensional image (voxel data) inside the body including the affected part (S11).
Based on the region of the affected area identified from the voxel data, conditions such as the treatment beam irradiation position, irradiation angle, irradiation range, radiation dose, and number of times are determined (S12).

  Then, based on the virtual viewpoint and virtual plane set from the design information 45 of the X-ray source 11 and the X-ray detector 12, a DRR image is generated by reconstructing a stereoscopic image (voxel data) of the patient 15 on the plane. (S13).

Then, at the stage of alignment of the X-ray source 11 and the X-ray detector 12, the reference member 21, the treatment space (X, Y, Z coordinate system) is disposed at a predetermined position of the reference point 20 (20 ₁ ˜20 ₆ ) is positioned (S14).
The X-ray output from the X-ray source 11 is emitted to the reference point 20 (20 _{1 to} 20 ₆ ), projected onto the X-ray detector 12, and an X-ray fluoroscopic image 13a of the reference body 21 is captured (S15). .
Then, from each of the regions 23 of the recognized reference points from the fluoroscopic image 13a (23 ₁ ~23 _6), the projective coordinates _{(u n, v n);} n = determining 1 to 6 (S16).

Further, the space coordinates (X _n , Y _n , Z _n ) of the reference point in the space coordinate system; n = 1 to 6 are converted into corresponding projective coordinates (u _n , v _n ); n = 1 to 6 A projection matrix P to be derived is derived (S17).
Based on the projection matrix P, the position information (l _x , l _y , l _z ) of the X-ray source 11 in the spatial coordinate system and the position information (c _x , c _y , c _z ) of the X-ray detector 12 are obtained. and orientation information _{(u x, u y, u} z) (v x, v y, v z) (w x, w y, w z) calculates the (S18).

  The positional information and the like of the X-ray source 11 and the X-ray detector 12 are compared with the design information 45, and the respective differences are calculated (S19). If this difference is outside the allowable range (No in S20), alignment adjustment of the X-ray source 11 and the X-ray detector 12 is performed (S21), and then the fluoroscopic image 13 of the reference body 21 is captured again. (S15-S19).

If the difference is within the allowable range (S20 Yes), the process proceeds to the beam irradiation treatment stage.
The bed 16 to which the patient 15 is fixed is moved to the determined position in the coordinate system (X, Y, Z) of the treatment space, and the position of the affected part of the patient 15 is adjusted to the isocenter (S22).

One X-ray fluoroscopic image 13b of the patient 15 is taken with the X-ray imaging apparatus 10 (S23), and this X-ray fluoroscopic image 13b is compared with the DRR image (S24).
And if both do not correspond within an allowable range (S25 No), the movement of the bed 16 is readjusted (S21-S22).
And if both correspond in the tolerance | permissible_range (S25 Yes), a treatment beam is irradiated to an affected part (S26 END).

  According to the alignment adjustment support device for an X-ray imaging apparatus of at least one embodiment described above, the position of the X-ray source, X Information about the position and orientation of the line detector can be calculated. As a result, it is not necessary to provide a special mechanical mechanism, and the operator does not need to acquire special skills, and the alignment adjustment of the X-ray source and X-ray detector constituting the X-ray imaging apparatus is performed. Can do.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

  The alignment adjustment support apparatus described above includes a control device in which a processor such as a dedicated chip, FPGA (Field Programmable Gate Array), GPU (Graphics Processing Unit), or CPU (Central Processing Unit) is highly integrated, and ROM ( Storage devices such as Read Only Memory (RAM) and Random Access Memory (RAM), external storage devices such as HDD (Hard Disk Drive) and SSD (Solid State Drive), display devices such as a display, and inputs such as a mouse and a keyboard The apparatus and the communication I / F are provided, and can be realized by a hardware configuration using a normal computer.

  A program executed by the alignment adjustment support apparatus is provided by being incorporated in advance in a ROM or the like. Alternatively, this program is stored in a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD, or flexible disk (FD) as an installable or executable file. You may make it do.

Further, the program executed by the alignment adjustment support apparatus of the X-ray imaging apparatus according to the present embodiment may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. .
In addition, this alignment adjustment support device can be configured by combining separate modules that perform each function of the components independently by a network or a dedicated line.

10 ... X-ray imaging device, 11 ... X-ray source, 12 ... X-ray detector, 13a, 13b ... X-ray fluoroscopic image, 15 ... patient, 16 ... bed, 20 (20 ₁ to 20 ₆₎ ... reference point, 21 Reference body, 23 (23 ₁ to 23 ₆ ) ... reference point region, 30 ... alignment adjustment support device, 31 ... perspective image input unit, 32 ... reference point projection coordinate determination unit, 33 ... projection matrix derivation unit, 34 ... Display unit 35 ... Manual setting unit 36 ... Input means 37a, 37b ... Storage unit 41 ... First calculation unit 41a ... X-ray source position calculation unit 41b ... X-ray detector position calculation unit 41c ... X Line detector attitude calculation unit, 42 ... second calculation unit, 43 ... third calculation unit, 45 ... design information, P ... projection matrix.

Claims (6)

X-rays output from the X-ray source are emitted to at least six reference points positioned in the coordinate system of the space where the X-ray source and the X-ray detector are installed, and projected onto the X-ray detector. A fluoroscopic image input unit for inputting the fluoroscopic image;
In the coordinate system of the perspective image, a determination unit that determines six projective coordinates representing each region from the recognized regions of the six reference points;
A derivation unit for deriving a projection matrix for coordinate conversion of the spatial coordinates of the six reference points in the coordinate system of the space into the corresponding six projection coordinates;
An X-ray comprising: a first calculation unit that calculates position information of the X-ray source in the coordinate system of the space and position information and posture information of the X-ray detector based on the projection matrix. Alignment support device for photographic equipment. In the alignment adjustment assistance apparatus of the X-ray imaging apparatus of Claim 1,
A second calculator that calculates an adjustment amount of the X-ray source based on design information of the X-ray source in the coordinate system of the space and the position information;
A third operation unit that calculates an adjustment amount of the X-ray detector based on design information of the X-ray detector in the coordinate system of the space, the position information, and the posture information. An alignment adjustment support apparatus for X-ray imaging equipment. In the alignment adjustment assistance apparatus of the X-ray imaging apparatus of Claim 1 or Claim 2,
An alignment adjustment support apparatus for an X-ray imaging apparatus, comprising: a display unit that displays the fluoroscopic image and displays the recognized reference point region overlaid on the fluoroscopic image. In the alignment adjustment assistance apparatus of the X-ray imaging apparatus of Claim 3,
An alignment adjustment support apparatus for an X-ray imaging apparatus, comprising: a manual setting unit that performs manual setting for recognizing the reference point region. Positioning at least six reference points in a coordinate system of a space in which the X-ray source and the X-ray detector are installed;
Emitting X-rays output from the X-ray source to six reference points;
Inputting a fluoroscopic image projected on the X-ray detector;
Determining, in the coordinate system of the perspective image, six projected coordinates representing each region from the recognized regions of the six reference points;
Deriving a projection matrix for coordinate transformation of the spatial coordinates of the six reference points in the spatial coordinate system into the corresponding six projected coordinates;
Calculating the position information of the X-ray source in the coordinate system of the space and the position information and posture information of the X-ray detector based on the projection matrix. Alignment support method. On the computer,
X-rays output from the X-ray source are emitted to at least six reference points positioned in the coordinate system of the space where the X-ray source and the X-ray detector are installed, and projected onto the X-ray detector. Inputting a transparent image,
Determining, in the coordinate system of the perspective image, six projective coordinates representing each area from the recognized areas of the six reference points;
Deriving a projection matrix for coordinate conversion of the spatial coordinates of the six reference points in the spatial coordinate system into the corresponding six projected coordinates;
An X-ray imaging apparatus, comprising: executing position information of the X-ray source in the coordinate system of the space, and position information and posture information of the X-ray detector based on the projection matrix. Alignment support program.

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