JP4718970B2 - X-ray collimator apparatus and X-ray CT apparatus - Google Patents

Description

The present invention, X-ray computed tomography apparatus for use in medical, etc. (hereinafter. Referred to as "X-ray CT apparatus") relates to the X-ray collimator device and the X-ray CT apparatus of integral incorporated into, particularly polar response characteristic And those that can improve the detector characteristics.

  An X-ray CT apparatus is known in which a collimator device is arranged in front of a detector unit with respect to an X-ray tube. In such an X-ray CT apparatus, for example, a plurality of detector units are arranged in a horizontal row to form an arcuate structure as a whole, and the collimator apparatus also has an arcuate structure as a whole. In addition, the surface direction of the collimator plate incorporated in the collimator apparatus faces the direction of the X-ray source (see, for example, Patent Document 1).

  The commercially available collimator device has grooves formed in the upper and lower supports arranged in parallel in the slicing direction, and a flattened collimator plate is inserted into the upper and lower pair of grooves in the assembled state. In addition, it has a structure in which the groove portion is adhesively cured. In addition, the groove | channel of an up-and-down support is formed so that it may face the assumed X-ray source.

  In recent years, as an X-ray CT apparatus, multi-slice (multi-row) has progressed, and trial manufacture has been made up to 256 rows. An X-ray CT apparatus having a 256-row detector is also called a high-speed cone beam three-dimensional CT, and converts the volume data obtained by scanning the X-ray tube around the human body at high speed into high-capacity three-dimensional voxel data. Thus, it is possible to perform image reconstruction. For this reason, since a three-dimensional X-ray CT image can be obtained in real time, the possibility of a real-time three-dimensional CT scan of a heart or the like, which has been considered difficult until now, has increased.

  However, the light receiving area of the 256-row detector unit used in this X-ray CT apparatus is large, and accordingly, it is particularly important to reduce the scattered X-ray dose transmitted through the subject. Note that a 256-row X-ray detector unit is not arranged in a horizontal row, but a plurality of units are arranged in the slice direction (vertical direction), and a surface detection type structure in which a plurality of units are further arranged in the horizontal direction is employed.

  Thus, when the width in the slice direction is increased to about 4 times the conventional one, the corresponding collimator single plate also becomes large, and the warp correction cannot be performed only by the rigidity of the collimator single plate. Therefore, as a method of manufacturing a collimator corresponding to the slice direction first, for the purpose of correcting the warpage of the collimator single plate, a collimator plate that covers multiple channels by dividing the collimator plate support on the X-ray transmitting surface is divided. I took the method.

  Supports are provided in the front and back in the direction of transmission when viewed from the X-ray source, grooves having different pitches are formed in the slice direction, and the collimator plate is directed to the X-ray focal point using the difference in pitch, and A multi-channel level collimator structure corresponding to the detector pack has been proposed.

Further, the module type X-ray collimator has a structure in which a plurality of (for example, 23) type X-ray collimator modules and a plurality of (for example, 25) type X-ray collimator modules are alternately arranged.
JP 2002-162472 A

  The collimator apparatus used in the above-described X-ray CT apparatus has the following problems. That is, as the detection range in the slice direction is expanded, it becomes difficult to correct warpage and deflection in the channel direction only by the rigidity of the single collimator plate. For this reason, when attaching a detector unit to a support, it becomes difficult to perform alignment well.

  When the collimator plate is deformed, the polar response characteristic (collimator characteristic change accompanying the X-ray tube focal point movement) indicating the characteristics of the X-ray collimator and the energy characteristic indicating the detector characteristics tend to vary, and the polar response and energy characteristics There was a problem that it was difficult to achieve a good continuous spatial distribution.

Accordingly, an object of the present invention is to provide an X-ray collimator apparatus and an X-ray CT apparatus capable of maintaining the collimator accuracy by preventing the deformation even when the collimator single plate is elongated in the slice direction. It is said.

In order to solve the above problems and achieve the object, the X-ray collimator and the X-ray CT apparatus of the present invention are configured as follows.

In an X-ray collimator apparatus that collimates X-rays that are irradiated from an X-ray source and incident on an X-ray detector, a pair of support members that are arranged in parallel in the slice direction and extend in the channel direction, A rear support plate arranged on the X-ray emission side with respect to the support member, a front support plate arranged on the X-ray incident side with respect to the support member, and a collimator plate arranged between the pair of support members When have, the pair of support members, and the said rear support plate, two sides of the collimator located to the pair of support member side, and the side that is located on the side of the rear support plate, A groove portion for holding the collimator plate is provided, and the groove portion is formed over substantially the entire slice direction in the rear support plate. One side which is located on the side of the side support plates, characterized in that it is inserted into the groove.

An X- ray source, an X-ray detector, and an X-ray collimator device that collimates X-rays irradiated from the X-ray source and incident on the X-ray detector, the X-ray collimator device in the slice direction A pair of support members arranged in parallel and extending in the channel direction, a rear support plate arranged on the X-ray emission side with respect to the pair of support members, and an X for the pair of support members A front support plate disposed on the line incident side, and a collimator plate disposed between the pair of support members, and the pair of support members and the rear support plate include the pair of support member sides. On the two sides of the collimator located at one side and on one side located on the side of the rear support plate, a groove for holding the collimator plate is provided, and the groove is formed on the rear support plate. Is formed over the substantially whole of the slice direction, one side located on the side of the side support plate after the collimator plate, characterized in that it is inserted into the groove.

  According to the present invention, even when a single collimator plate is elongated in the slicing direction, it is possible to maintain the collimator accuracy by preventing the deformation.

  FIG. 1 is an exploded perspective view showing an X-ray collimator apparatus 10 according to a first embodiment of the present invention. In FIG. 1, S indicates the slice direction, and C indicates the channel direction. The X-ray collimator apparatus 10 is an apparatus constituting an X-ray detection apparatus incorporated in an X-ray CT apparatus, and is disposed in front of the X-ray detector with respect to an X-ray source that irradiates X-rays. This device is used to remove scattered X-rays that are harmful to X-ray imaging.

  The X-ray collimator apparatus 10 includes a support mechanism 20 and a plurality of collimator single plates 30 held by the support mechanism 20.

  The support mechanism 20 includes a pair of collimator supports (support members) 21 and 22 extending in the channel direction C and arranged in parallel in the slice direction S, and a pair of side plates 23 provided at both ends of the collimator supports 21 and 22. , 24, a rear support plate 25 provided on the outer peripheral side of the collimator supports 21, 22, and a front support plate 26 provided on the inner peripheral side of the collimator supports 21, 22.

  A plurality of grooves 21 a, 22 a, 25 a for inserting a collimator single plate (collimator plate) 30 are formed in the collimator supports 21, 22 and the rear support plate 25 along the channel direction C. These groove portions 21a, 22a, and 25a are arranged so that the surface of the collimator single plate 30 is parallel to the slice direction S when the X-ray collimator apparatus 10 is incorporated in the X-ray CT apparatus, and all the collimators The X-ray source is formed on the extended line of the surface of the single plate 30.

  The front support plate 26 is not formed with grooves corresponding to the above-described grooves 21a, 22a, 25a, and is screwed to the collimator supports 21, 22 and the side plates 23, 24.

  The collimator single plate 30 is made of a material having high X-ray absorption such as molybdenum.

  In the X-ray collimator apparatus 10 configured as described above, the collimator single plate 30 is supported by the collimator supports 21 and 22 and the rear support plate 25, and the collimator supports 21 and 22 include the rear support plate 25 and the front side. The support plate 26 provides a sealed structure and increases rigidity. For this reason, even when the collimator single plate 30 having a large area is used, the collimator single plate 30 can be warped and deflected in the channel direction, and the rigidity can be increased. Therefore, when attaching the detector unit to the collimator supports 21 and 22, it becomes easy to perform good alignment.

  Further, the continuity of the spatial distribution of the polar response characteristic which is the X-ray collimator characteristic and the energy characteristic which is the detector characteristic can be easily obtained.

  As described above, according to the X-ray collimator apparatus 10 according to the present embodiment, the detector is enlarged, the detection range in the slice direction is enlarged, and the collimator single plate is enlarged correspondingly. However, it is possible to maintain the collimator accuracy and improve the X-ray collimator characteristics by preventing deformation such as warpage and deflection of the collimator single plate.

Figure 2 is an exploded perspective view showing a reference example of the above-mentioned X-ray collimator equipment, FIG. 3 is a fragmentary cross-sectional view of the rear support plate 25. 2 that are the same as those in FIG. 1 are assigned the same reference numerals, and detailed descriptions thereof are omitted.

In the present reference example, the rear support plate 25 is formed with protrusions 25b only in part instead of the grooves 25a formed over the entire slice direction S. If comprised in this way, it will become easy to insert the collimator single board 30 in the clearance gap between the protrusion 25b and the protrusion 25b, and workability | operativity will improve.

  In FIG. 4, the shape of the protrusion 25 c is a triangular shape with the central portion at the apex. Even in this case, an effect similar to that of the protrusion 25b of FIG. 3 can be obtained.

  FIG. 5 is an exploded perspective view showing the X-ray collimator apparatus 40 according to the second embodiment of the present invention. In FIG. 5, the same functional parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the X-ray collimator device 40, a rear support plate 41 is used instead of the rear support plate 25. The rear support plate 41 is composed of a plurality of module plate members 42. In the module plate member 42, a groove 42a is formed in the same manner as the groove 25a described above.

  In the X-ray collimator apparatus 40 configured as described above, the same effects as those of the X-ray collimator apparatus 10 described above can be obtained, the accumulated processing error in the width of the groove 42a and the like is reduced, and the collimator single plate 30 is inserted. It becomes easy.

  In addition, as shown in FIG. 6, the positioning of the collimator single plate 30 is improved by adjusting the position of the module plate 42 while measuring the angle of the collimator single plate 30 located at the center of each module plate 42. As a result, it becomes easy to insert the collimator single plate 30 into the groove of the collimator support, and the workability is improved.

  As described above, also in the X-ray collimator apparatus 40 according to the present embodiment, it is possible to obtain the same effects as the X-ray collimator apparatus 10 and to improve workability.

  FIG. 7 is an exploded perspective view showing an X-ray collimator apparatus 50 according to the third embodiment of the present invention. In FIG. 7, the same functional parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 7, reference numeral 70 denotes a jig for positioning the collimator single plate 30.

  The X-ray collimator apparatus 50 includes a support mechanism 60 and a plurality of collimator single plates 30 held by the support mechanism 60.

  The support mechanism 60 includes a pair of collimator supports 61 and 62 extending in the channel direction C and arranged in parallel in the slice direction S, and a pair of side plates 63 and 64 provided at both ends of the collimator supports 61 and 62. A rear support plate 65 provided on the outer peripheral side of the collimator supports 61 and 62 and a front support plate (not shown) provided on the inner peripheral side of the collimator supports 61 and 62 are provided.

  The collimator supports 61 and 62 are provided with groove portions 61 a and 62 b for inserting the collimator single plate 30.

  In the X-ray collimator device 50, the collimator single plate 30 is inserted into the grooves 61a and 62b, and the collimator single plate 30 is corrected using the jig 70 and fixed with an adhesive. The jig 70 is removed after the adhesive is cured. After the adhesive is cured, the jig 70 is not removed and a fixing member can be used to further increase the rigidity.

  In the X-ray collimator device 50 according to the present embodiment, the collimator single plate 30 can be corrected without using the rear support plate 65 or the front support plate, and the same effect as the X-ray collimator device 10 can be obtained. Obtainable.

  FIG. 8 is an exploded perspective view showing an X-ray collimator apparatus 80 according to the fourth embodiment of the present invention. In FIG. 8, the same functional parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The X-ray collimator apparatus 80 includes a support mechanism 90 and a plurality of collimator single plates 30 held by the support mechanism 90. The support mechanism 90 includes an arcuate rear support plate 91 and a front support plate 92 arranged in parallel along the X-ray irradiation direction. The rear support plate 91 and the front support plate 92 include: Groove portions 91a and 92a are provided along the channel direction C. The collimator single plate 30 is inserted into the grooves 91a and 92a of the rear support plate 91 and the front support plate 92 from above in the figure, whereby the X-ray collimator device 80 is configured.

  In the X-ray collimator apparatus 80 configured as described above, the same effects as those of the X-ray collimator apparatus 10 described above can be obtained, and the number of constituent members can be reduced.

  FIG. 9 is an exploded perspective view showing a modification of the X-ray collimator apparatus 80 described above. 9, the same reference numerals are given to the same functional parts as those in FIG. 1, and detailed description thereof will be omitted.

  In this modification, the rear support plate 91 and the front support plate 92 are divided into two in the slice direction S. Also in this modification, the same effect as that of the X-ray collimator apparatus 80 can be obtained, and the grooves 91a and 92a can be easily formed.

  FIG. 10 is an exploded perspective view showing the X-ray collimator apparatus 100 according to the fifth embodiment of the present invention, and FIG. 11 is a cross-sectional view showing the main part of the X-ray collimator apparatus 100. In these drawings, the same functional parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The X-ray collimator apparatus 100 includes a support mechanism 110 and a plurality of collimator single plates 30 held by the support mechanism 110.

  The support mechanism 110 includes a pair of collimator supports 111 and 112 extending in the channel direction C and arranged in parallel in the slice direction S, and a pair of side plates 113 and 114 provided at both ends of the collimator supports 111 and 112, A rear support plate 115 provided on the outer peripheral side of the collimator supports 111 and 112, and a first front support plate 116 and a second front support plate 117 provided on the inner peripheral side of the collimator supports 111 and 112 are provided. . The widths in the slice direction S of the rear support plate 115, the first front support plate 116, and the second front support plate 117 are all set to 1/3 or less of the width between the collimator supports 111 and 112.

  The rear support plate 115, the first front support plate 116, and the second front support plate 117 are formed with a plurality of grooves 115a, 116a, 117a for inserting the collimator single plate 30 along the channel direction C. Yes. These groove portions 115a, 116a, and 117a are arranged so that the surface of the collimator single plate 30 is parallel to the slice direction S when the X-ray collimator apparatus 100 is incorporated in the X-ray CT apparatus, and all the collimators The X-ray source is formed on the extended line of the surface of the single plate 30.

  In the X-ray collimator apparatus 100 configured as described above, the collimator single plate 30 is supported by the rear support plate 115, the first front support plate 116, and the second front support plate 117, and the collimator supports 111 and 112 are The rigidity is increased by the rear support plate 115, the first front support plate 116, and the second front support plate 117. For this reason, the rigidity of the collimator single plate 30 can be increased, and the warp and the deflection in the channel direction can be corrected. Therefore, when attaching the detector unit to the collimator supports 111 and 112, it becomes easy to perform good alignment. In addition, since the machining portion is shortened as compared with the case where the machining is performed in the entire slicing direction S in the grooving, the machining of the groove portions 115a, 116a, and 117a is facilitated, and workability can be improved.

  As described above, according to the X-ray collimator apparatus 100 according to the present embodiment, it is possible to obtain the same effects as those of the X-ray collimator apparatus 10 and to facilitate the groove processing.

  FIG. 12 is a perspective view showing an X-ray collimator apparatus 100A according to a modification of the above-described X-ray collimator apparatus 100, and FIG. 13 is a cross-sectional view showing the main part of the X-ray collimator apparatus 100A. In these drawings, the same functional parts as those in FIGS. 10 and 11 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this modification, grooves 111 a, 112 a, 116 a, and 117 a for guiding the collimator plate 30 are formed in the collimator supports 111 and 112, the first front support plate 116, and the second front support plate 117. These groove portions 111a, 112a, 116a, and 117a are arranged so that the surface of the collimator single plate 30 is parallel to the slice direction S when the X-ray collimator device 100A is incorporated in the X-ray CT device, and all The X-ray source is formed on the extended line of the surface of the collimator single plate 30.

  Also in this modification, the same effect as the X-ray collimator apparatus 100 can be obtained.

  FIG. 14 is a perspective view showing an X-ray collimator apparatus 100B according to a modification of the X-ray collimator apparatus 100 described above, and FIG. 15 is a cross-sectional view showing a main part of the X-ray collimator apparatus 100B. In these drawings, the same functional parts as those in FIGS. 10 and 11 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the present modification, a third front support plate 118 is provided between the first front support plate 116 and the second front support plate 117.

  The rear support plate 115, the first front support plate 116, the second front support plate 117, and the third front support plate 118 have grooves 115a, 116a, 117a, 118a for inserting the collimator single plate 30 in the channel direction C. A plurality are formed along. These groove portions 115a, 116a, 117a, and 118a are arranged so that the surface of the collimator single plate 30 is parallel to the slice direction S when the X-ray collimator device 100B is incorporated in the X-ray CT device, and all The X-ray source is formed on the extended line of the surface of the collimator single plate 30.

  Also in this modification, the same effect as the X-ray collimator apparatus 100 can be obtained, and the rigidity can be further increased.

  FIG. 16 is a perspective view showing an X-ray collimator apparatus 100C according to a modification of the X-ray collimator apparatus 100 described above, and FIG. 17 is a cross-sectional view showing a main part of the X-ray collimator apparatus 100C. In these drawings, the same functional parts as those in FIGS. 14 and 15 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this modification, the rear support plate 119 provided from the collimator support 111 to the collimator support 112 is used instead of the rear support plate 115.

  Groove portions 111a, 112a, 116a, 117a, 118a for guiding the collimator plate 30 are formed in the collimator supports 111, 112, the first front support plate 116, the second front support plate 117, and the third front support plate 118. These groove portions 111a, 112a, 116a, 117a, 118a are arranged so that the surface of the collimator single plate 30 is parallel to the slice direction S when the X-ray collimator device 100C is incorporated in the X-ray CT device, and The X-ray source is formed on the extended line of the surface of all the collimator single plates 30.

  In the present embodiment, collimator supports 21, 22 and the like as an example of a support member, a collimator single plate 30 as an example of a collimator plate, a module plate 42 as an example of a plate material, and a fixing member as an example of a jig. Used.

  Also in this modified example, the same effects as those of the X-ray collimator apparatus 100 can be obtained, the rigidity can be further increased, and the processing and assembly can be facilitated.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined .
The invention described in the scope of the claims of the present application is appended below.
[1] In an X-ray collimator device that collimates X-rays irradiated from an X-ray source and incident on an X-ray detector, a pair of support members arranged in parallel in the slice direction and extended in the channel direction; The rear support plate disposed on the X-ray emission side with respect to the pair of support members, the front support plate disposed on the X-ray incident side with respect to the support member, and the pair of support members. An X-ray collimator device comprising: a collimator plate; and a groove portion that is provided on the pair of support members, the rear support plate, and the front support plate and holds the collimator plate.
[2] The X-ray collimator device according to [1], wherein the rear support plate is formed of a plurality of plate members arranged along a channel direction.
[3] The X-ray collimator device according to [1], wherein a width in a slice direction of the rear support plate is formed to be 1/3 or less of a width between the pair of support members.
[4] The X-ray collimator device according to claim 1, wherein the width of the one front support plate in the slice direction is formed to be 1/3 or less of the width between the pair of support members.
[5] In an X-ray collimator device that collimates X-rays irradiated from an X-ray source and incident on an X-ray detector, a pair of support members arranged in parallel in the slice direction and extending in the channel direction; The rear support plate disposed on the X-ray emission side with respect to the pair of support members, the front support plate disposed on the X-ray incident side with respect to the support member, and the pair of support members. An X-ray collimator device comprising: a collimator plate positioned by a detachable fixing member and fixed to the support member and the rear support plate by an adhesive.

1 is an exploded perspective view showing an X-ray collimator device according to a first embodiment of the present invention. The disassembled perspective view which shows the reference example of the same X-ray collimator apparatus. Sectional drawing which shows the principal part which shows the same X-ray collimator apparatus. The principal part sectional view showing another example of the X-ray collimator device. The disassembled perspective view which shows the X-ray collimator apparatus which concerns on the 2nd Embodiment of this invention. Explanatory drawing which shows the assembly method by the same X-ray collimator apparatus. The disassembled perspective view which shows the X-ray collimator apparatus and jig | tool which concern on the 3rd Embodiment of this invention. The disassembled perspective view which shows the X-ray collimator apparatus which concerns on the 4th Embodiment of this invention. The disassembled perspective view which shows the modification of the same X-ray collimator apparatus. The disassembled perspective view which shows the X-ray collimator apparatus which concerns on the 5th Embodiment of this invention. Sectional drawing which shows the principal part which shows the same X-ray collimator apparatus. The disassembled perspective view which shows the modification of the same X-ray collimator apparatus. Sectional drawing which shows the principal part which shows the same X-ray collimator apparatus. The disassembled perspective view which shows the modification of the same X-ray collimator apparatus. Sectional drawing which shows the principal part which shows the same X-ray collimator apparatus. The disassembled perspective view which shows the modification of the same X-ray collimator apparatus. Sectional drawing which shows the principal part which shows the same X-ray collimator apparatus.

Explanation of symbols

  10, 40, 50, 80 ... X-ray collimator device, 20, 60, 90, 110 ... support mechanism, 21, 22, 61, 62 ... collimator support, 25, 41, 65, 91, 109, 115, 119 ... after Side support plate, 26, 92 ... front support plate, 30 ... single collimator plate, 42 ... module plate material, 70 ... jig, 111, 112 ... collimator support, 116 ... first front support plate, 117 ... second front support plate 118 ... Third front support plate.

Claims (3)

In an X-ray collimator device that collimates X-rays irradiated from an X-ray source and incident on an X-ray detector,
A pair of support members arranged in parallel in the slice direction and extending in the channel direction;
For these pair of support members, a rear support plate disposed on the X-ray emission side,
For the support member, a front support plate disposed on the X-ray incident side;
Anda collimator plate disposed between the pair of support members,
The pair of support members, and the said rear support plate, two sides of the collimator located to the pair of support member side, and the side that is located on the side of the rear support plate, holding said collimator plate A groove is provided, and the groove is formed over substantially the entire slice direction in the rear support plate, and one side located on the rear support plate side of the collimator plate is substantially the entire slice direction. An X-ray collimator device, wherein the X-ray collimator device is inserted into a groove formed over the space. The X-ray collimator device according to claim 1, wherein the rear support plate is formed of a plurality of plate members arranged along the channel direction. An X-ray source;
An X-ray detector;
An X-ray collimator device for collimating X-rays irradiated from the X-ray source and incident on the X-ray detector;
The X-ray collimator device is arranged in parallel in the slice direction and a pair of support members extended in the channel direction;
For these pair of support members, a rear support plate disposed on the X-ray emission side,
For the pair of support members, a front support plate disposed on the X-ray incident side;
Anda collimator plate disposed between the pair of support members
The pair of support members and the rear support plate hold the collimator plate on two sides of the collimator located on the pair of support members side and one side located on the rear support plate side. A groove is provided, and the groove is formed in the rear support plate over substantially the entire slice direction, and one side located on the rear support plate side of the collimator plate is inserted into the groove. X-ray CT apparatus characterized by there.

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