JP4479503B2 - Tomography equipment - Google Patents

Tomography equipment Download PDF

Info

Publication number
JP4479503B2
JP4479503B2 JP2004380609A JP2004380609A JP4479503B2 JP 4479503 B2 JP4479503 B2 JP 4479503B2 JP 2004380609 A JP2004380609 A JP 2004380609A JP 2004380609 A JP2004380609 A JP 2004380609A JP 4479503 B2 JP4479503 B2 JP 4479503B2
Authority
JP
Japan
Prior art keywords
image
optical imaging
marker
dimensional position
unit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2004380609A
Other languages
Japanese (ja)
Other versions
JP2006181252A (en
Inventor
明徳 藤田
四郎 及川
尚孝 森田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shimadzu Corp
Original Assignee
Shimadzu Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shimadzu Corp filed Critical Shimadzu Corp
Priority to JP2004380609A priority Critical patent/JP4479503B2/en
Publication of JP2006181252A publication Critical patent/JP2006181252A/en
Application granted granted Critical
Publication of JP4479503B2 publication Critical patent/JP4479503B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Apparatus For Radiation Diagnosis (AREA)

Description

この発明は、医療分野や工業分野に用いられ、被検体に電磁波を照射して得られた投影像から断層像または／および３次元画像を再構成する断層撮影装置に関する。   The present invention relates to a tomographic apparatus that is used in the medical field or industrial field and reconstructs a tomographic image and / or a three-dimensional image from a projection image obtained by irradiating a subject with electromagnetic waves.

この種の断層撮影装置では、例えば、被検体の撮影時、定期点検または故障発生などの保守点検時などに、装置の保守・校正を行う必要がある。そのため、従来、特許文献１に開示されているものが知られている。   In this type of tomography apparatus, it is necessary to perform maintenance / calibration of the apparatus, for example, during imaging of a subject, during periodic inspections, or during maintenance inspections such as occurrence of failures. Therefore, what is conventionally disclosed in Patent Document 1 is known.

この従来例によれば、被検体を載置する天板に校正ファントムを載置して照射手段と検出手段とを走査手段により一周走査し、得られる投影像から回転断層軸の投影線を求め、その求められた回転断層軸まわりの厳密な円軌道上に照射手段と検出手段が存在することが、断層像において偽像の発生を防止する要件であり、その回転断層軸の投影線に対して面検出器の所定の画素列が一致するように面検出器を移動調整するように構成している。   According to this conventional example, the calibration phantom is placed on the top plate on which the subject is placed, the irradiation means and the detection means are scanned once by the scanning means, and the projection line of the rotating tomographic axis is obtained from the obtained projection image. The existence of irradiation means and detection means on the exact circular orbit around the determined rotational tomographic axis is a requirement to prevent the generation of false images in the tomographic image, The surface detector is moved and adjusted so that predetermined pixel columns of the surface detector coincide with each other.

特開２００３−６１９４４号公報JP 2003-61944 A

しかしながら、従来例の場合、照射手段と検出手段の軌道が、回転断層軸を中心として厳密な円軌道上から少しでもズレていた場合は、厳密な校正が不可能であった。また、回転断層軸の投影線を求めるために、少なくとも１８０°以上回転させる必要があり、例えば、４０°のように走査範囲が狭いような場合でも、広範囲の走査を行わなければならず、校正に手間がかかる欠点があった。更に、最終的には面検出器の移動調整をも行わなければならず、必要な画像を得るまでに多大な手間を要する欠点があった。   However, in the case of the conventional example, if the orbits of the irradiation means and the detection means are slightly deviated from the exact circular orbit around the rotational tomographic axis, exact calibration is impossible. Further, in order to obtain the projection line of the rotating tomographic axis, it is necessary to rotate at least 180 ° or more. For example, even when the scanning range is narrow such as 40 °, a wide range of scanning must be performed, and calibration is performed. There was a drawback that it took time. Further, finally, the movement of the surface detector must be adjusted, and there is a drawback that a great deal of labor is required to obtain a necessary image.

このような問題を対して、先行特許出願（特願２００４−１６３０９５）の明細書に記載の発明（以下、先行発明という）によって問題の解消が図られている。   To solve such a problem, the invention (hereinafter referred to as the prior invention) described in the specification of the prior patent application (Japanese Patent Application No. 2004-163095) solves the problem.

図７は、先行発明に係る断層撮影装置の全体構成図である。この断層撮影装置の校正ファントムとしては、同一平面上に無い４個以上のマーカを３次元的に配置したものを用いる。また、３次元位置情報検出部１１３は、この校正ファントムの投影像と、校正ファントム内のマーカの配置情報とに基づいて、Ｘ線管１０２及び平面検出器１０３の３次元位置情報を求める。なお、３次元位置情報検出部１１３によるこの処理は、被検体を撮影する前に予め行う。   FIG. 7 is an overall configuration diagram of the tomography apparatus according to the prior invention. As a calibration phantom of this tomographic apparatus, a tomographic array of four or more markers that are not on the same plane is used. Further, the three-dimensional position information detection unit 113 obtains three-dimensional position information of the X-ray tube 102 and the flat detector 103 based on the projection image of the calibration phantom and the marker arrangement information in the calibration phantom. Note that this processing by the three-dimensional position information detection unit 113 is performed in advance before imaging the subject.

図８は、先行発明に係る断層撮影装置の動作を説明するフローチャートである。 先ず、校正ファントムの投影像の撮影を行い（ステップＴ１）、その投影像と校正ファントム内部の各マーカの３次元配置情報からＸ線管１０２と平面検出器１０３の３次元位置情報を３次元位置情報検出部１１３により求める（ステップＴ２）。全ての投影像について３次元位置情報を求めて（ステップＴ３）から、それらの３次元位置情報を３次元位置情報記憶部１１４に記憶保存する（ステップＴ４）。次いで、校正ファントムを撮影した時と同じ軌道・同じタイミングで、再構成を行う被検体の投影像の撮影等を行う（ステップＴ５）。得られた被検体の投影像の撮影データと、３次元位置情報記憶部１１４に記憶されたＸ線管１０２および平面検出器１０３の３次元位置情報に基づいて、被検体に対する再構成演算処理を行い、断層像あるいは３次元ボリュームデータを作成する（ステップＴ６）。断層像等は断層像／３次元ボリュームデータ保存部１１６に記憶保存し、要求に応じて画像表示装置１１０に出力して表示する（ステップＴ７）。   FIG. 8 is a flowchart for explaining the operation of the tomography apparatus according to the prior invention. First, the projection image of the calibration phantom is taken (step T1), and the three-dimensional position information of the X-ray tube 102 and the flat detector 103 is obtained from the projection image and the three-dimensional arrangement information of each marker inside the calibration phantom. Obtained by the information detector 113 (step T2). After obtaining three-dimensional position information for all projection images (step T3), the three-dimensional position information is stored and saved in the three-dimensional position information storage unit 114 (step T4). Next, the projection image of the subject to be reconstructed is taken at the same trajectory and the same timing as when the calibration phantom was shot (step T5). Based on the obtained imaging data of the projected image of the subject and the three-dimensional position information of the X-ray tube 102 and the flat detector 103 stored in the three-dimensional position information storage unit 114, reconstruction calculation processing for the subject is performed. And tomographic image or three-dimensional volume data is created (step T6). The tomographic image or the like is stored and stored in the tomographic image / three-dimensional volume data storage unit 116, and is output to the image display device 110 and displayed on demand (step T7).

これによれば、円軌道以外の軌道上を走査する場合においても、Ｘ線管１０２及び平面検出器１０３の３次元位置情報を精度よく得られるので、厳密な校正が可能となる。   According to this, even when scanning on a trajectory other than a circular trajectory, the three-dimensional position information of the X-ray tube 102 and the flat detector 103 can be obtained with high accuracy, so that strict calibration is possible.

しかし、先行発明に係る断層撮影装置では、校正ファントムの投影像の撮影時と、被検体の投影像の撮影時とは、同じ軌道上を回転することを前提にしており、偶発的な微小な走査のずれの発生や、メカ特性の経時的な変化を抑えるものではない。よって、画質が劣化する可能性が残っている。   However, in the tomography apparatus according to the prior invention, it is assumed that the projection image of the calibration phantom and the projection image of the subject are rotated on the same trajectory, and the accidental minute It does not suppress the occurrence of scanning deviations or changes in mechanical characteristics over time. Therefore, there is a possibility that the image quality deteriorates.

この発明は、このような事情に鑑みてなされたものであって、より厳密な校正を行い、断層画像の画質の劣化を防止することができる断層撮影装置を提供することを目的とする。   The present invention has been made in view of such circumstances, and an object of the present invention is to provide a tomographic apparatus capable of performing more strict calibration and preventing deterioration of the image quality of a tomographic image.

この発明は、このような目的を達成するために、次のような構成をとる。
すなわち、請求項１に記載の発明は、電磁波を被検体に照射する照射手段と、前記被検体を透過する電磁波を検出する検出手段と、前記照射手段および前記検出手段を互いに連動して移動させる移動手段と、前記移動手段により移動される前記検出手段から得られた投影像の一群に基づいて再構成演算処理を行い、断層像または／および３次元画像を作成する画像作成手段とを備えた断層撮影装置において、前記照射手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに所定の位置に配置されるマーカの光学像を撮像する第１光学撮像手段と、前記検出手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに前記マーカの光学像を撮像する第２光学撮像手段と、前記第１光学撮像手段及び前記第２光学撮像手段の検知結果に基づいて、前記照射手段及び前記検出手段の３次元位置を算定する算定手段とを備え、前記算定手段は、前記マーカの３次元位置と、前記第１光学撮像手段から得られた画像と、前記第１光学撮像手段及び前記照射手段の間の相対的な位置関係とに基づいて、前記照射手段の３次元位置を算定し、かつ、前記マーカの３次元位置と、前記第２光学撮像手段から得られた画像と、前記第２光学撮像手段及び前記検出手段の間の相対的な位置関係とに基づいて、前記検出手段の３次元位置を算定し、前記画像作成手段は、前記算定手段により算定された前記照射手段及び前記検出手段の３次元位置を用いて前記再構成演算処理を行い、前記装置は、さらに、固定的に設置されて、前記マーカの光学像を撮像する第３光学撮像手段を備え、前記マーカは前記移動手段に配置され、前記算定手段は、さらに、前記第３光学撮像手段の３次元位置と、前記第３光学撮像手段から得られた画像とに基づいて、前記マーカの３次元位置を求めることを特徴とするものである。 In order to achieve such an object, the present invention has the following configuration.
That is, according to the first aspect of the present invention, the irradiation means for irradiating the subject with electromagnetic waves, the detection means for detecting the electromagnetic waves transmitted through the subject, and the irradiation means and the detection means are moved in conjunction with each other. A moving unit; and an image creating unit configured to perform a reconstruction calculation process based on a group of projection images obtained from the detecting unit moved by the moving unit to create a tomographic image and / or a three-dimensional image. In the tomography apparatus, when a group of projection images is obtained at a position where the relative positional relationship with the irradiating means is constant, a marker placed at a predetermined position at each time point when each projection image is obtained . The marker is provided at a position where a relative positional relationship between the first optical imaging unit that captures an optical image and the detection unit is constant, and when obtaining a group of projection images, the marker is obtained at each time point when each projection image is obtained. Light of Comprising a second optical imaging means for capturing an image, based on the detection result of the first optical imaging means and the second optical imaging means, and calculating means for calculating the three-dimensional position of the irradiating means and the detecting means The calculation means is based on a three-dimensional position of the marker, an image obtained from the first optical imaging means, and a relative positional relationship between the first optical imaging means and the irradiation means. Calculating a three-dimensional position of the irradiating means; and a relative relationship between the three-dimensional position of the marker, an image obtained from the second optical imaging means, and the second optical imaging means and the detecting means. Based on the positional relationship, the three-dimensional position of the detecting means is calculated, and the image creating means uses the three-dimensional position of the irradiation means and the detecting means calculated by the calculating means to perform the reconstruction calculation process. the stomach line, said device Furthermore, the optical system includes a third optical imaging unit that is fixedly installed and captures an optical image of the marker, the marker is disposed on the moving unit, and the calculation unit further includes 3 of the third optical imaging unit. A three-dimensional position of the marker is obtained based on a three-dimensional position and an image obtained from the third optical imaging means .

［作用・効果］請求項１に記載の発明によれば、第１光学撮像手段と第２光学撮像手段とは、それぞれ照射手段または検出手段との相対的な位置関係が一定となる位置に設けられている。すなわち、移動手段等の外力を受けても、たわみ等が発生せず、両者の相対的な位置関係が変位することがないように第１光学撮像手段と第２光学撮像手段が設置されている。これら第１光学撮像手段と第２光学撮像手段とによって、マーカを検知する。そして、第１光学撮像手段及び照射手段の間の相対的な位置関係と、第２光学撮像手段及び検出手段の間の相対的な位置関係と、マーカの３次元位置とを考慮することで、算定手段は、第１光学撮像手段と第２光学撮像手段との検知結果に基づいて、照射手段と検出手段との３次元位置を正確に算定することができる。 [Operation / Effect] According to the invention described in claim 1, the first optical imaging means and the second optical imaging means are provided at positions where the relative positional relationship between the irradiation means and the detection means is constant. It has been. In other words, the first optical imaging means and the second optical imaging means are installed so that even if an external force from the moving means or the like is applied, no deflection or the like occurs and the relative positional relationship between the two does not change. . The marker is detected by the first optical imaging unit and the second optical imaging unit . And by considering the relative positional relationship between the first optical imaging means and the irradiation means, the relative positional relationship between the second optical imaging means and the detection means, and the three-dimensional position of the marker , The calculation means can accurately calculate the three-dimensional positions of the irradiation means and the detection means based on the detection results of the first optical imaging means and the second optical imaging means .

さらに、第１、第２光学撮像手段は、被検体の投影像の一群を得る際、各投影像が得られる時点ごとにマーカを検知する。マーカは所定の位置に配置されている。これにより、投影像を取得する各時点の照射手段及び検出手段の３次元位置を、推定することなく、直接算定しているので常に正確である。よって、照射手段または検出手段の軌道が偶発的にずれる場合や、軌道が経時的に変化してしまう場合であっても、照射手段および検出手段の正確な３次元位置を得ることができる。そして、得られた３次元位置を再構成演算処理に用いることで、画像作成手段はより厳密な校正を常に行うことができる。したがって、作成される断層画像や３次元画像の画質が劣化することがない。 Furthermore, when obtaining a group of projection images of the subject, the first and second optical imaging means detect a marker at each time point when each projection image is obtained. The marker is arranged at a predetermined position. As a result, the three-dimensional positions of the irradiation means and the detection means at each time point at which the projection image is acquired are directly calculated without being estimated, and thus are always accurate. Therefore, even when the trajectory of the irradiating means or the detecting means is accidentally shifted or the trajectory changes with time, it is possible to obtain accurate three-dimensional positions of the irradiating means and the detecting means. Then, by using the obtained three-dimensional position for the reconstruction calculation process, the image creating means can always perform more strict calibration. Therefore, the image quality of the created tomographic image or three-dimensional image does not deteriorate.

また、第１光学撮像手段と第２光学撮像手段とからマーカの画像が取得される。算定手段は、これらの画像から各光学撮像手段とマーカとの間の相対的な位置関係を求めることができる。そして、これらの位置関係について、マーカの３次元位置を考慮することで、各光学撮像手段の３次元位置が求められる。さらに、各光学撮像手段と照射手段、または検出手段との相対的な位置関係を考慮すると、照射手段及び検出手段の３次元位置を算定することができる。 In addition, a marker image is acquired from the first optical imaging unit and the second optical imaging unit. The calculation means can obtain the relative positional relationship between each optical imaging means and the marker from these images. And about these positional relationships, the three-dimensional position of each optical imaging means is calculated | required by considering the three-dimensional position of a marker. Furthermore, considering the relative positional relationship between each optical imaging means and the irradiation means or the detection means, the three-dimensional positions of the irradiation means and the detection means can be calculated.

また、固定的に設置される第３光学撮像手段を備えることで、マーカの３次元位置を求めることができる。よって、マーカが移動手段に設置されてその３次元位置が変位する場合であっても、マーカの３次元位置を常に正確に求めることができる。 In addition, by providing the third optical imaging means that is fixedly installed, the three-dimensional position of the marker can be obtained. Therefore, even when the marker is placed on the moving means and its three-dimensional position is displaced, the three-dimensional position of the marker can always be obtained accurately.

また、請求項２に記載の発明は、電磁波を被検体に照射する照射手段と、前記被検体を透過する電磁波を検出する検出手段と、前記照射手段および前記検出手段を互いに連動して移動させる移動手段と、前記移動手段により移動される前記検出手段から得られた投影像の一群に基づいて再構成演算処理を行い、断層像または／および３次元画像を作成する画像作成手段とを備えた断層撮影装置において、前記照射手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに所定の位置に配置されるマーカの光学像を撮像する第１光学撮像手段と、前記検出手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに前記マーカの光学像を撮像する第２光学撮像手段と、前記第１光学撮像手段及び前記第２光学撮像手段の検知結果に基づいて、前記照射手段及び前記検出手段の３次元位置を算定する算定手段とを備え、前記算定手段は、前記マーカの３次元位置と、前記第１光学撮像手段から得られた画像と、前記第１光学撮像手段及び前記照射手段の間の相対的な位置関係とに基づいて、前記照射手段の３次元位置を算定し、かつ、前記マーカの３次元位置と、前記第２光学撮像手段から得られた画像と、前記第２光学撮像手段及び前記検出手段の間の相対的な位置関係とに基づいて、前記検出手段の３次元位置を算定し、前記画像作成手段は、前記算定手段により算定された前記照射手段及び前記検出手段の３次元位置を用いて前記再構成演算処理を行い、前記マーカは３点以上であることを特徴とするものである。 In the invention according to claim 2 , the irradiation unit for irradiating the subject with electromagnetic waves, the detection unit for detecting the electromagnetic waves transmitted through the subject, and the irradiation unit and the detection unit are moved in conjunction with each other. A moving unit; and an image creating unit configured to perform a reconstruction calculation process based on a group of projection images obtained from the detecting unit moved by the moving unit to create a tomographic image and / or a three-dimensional image. In the tomography apparatus, when a group of projection images is obtained at a position where the relative positional relationship with the irradiating means is constant, a marker placed at a predetermined position at each time point when each projection image is obtained . The marker is provided at a position where a relative positional relationship between the first optical imaging unit that captures an optical image and the detection unit is constant, and when obtaining a group of projection images, the marker is obtained at each time point when each projection image is obtained. Optical image Comprising a second optical imaging means for imaging, on the basis of the detection result of the first optical imaging means and the second optical imaging means, and calculating means for calculating the three-dimensional position of the irradiating means and the detecting means, wherein The calculating means is based on the three-dimensional position of the marker, the image obtained from the first optical imaging means, and the relative positional relationship between the first optical imaging means and the irradiation means. A three-dimensional position of the means, and a relative positional relationship between the three-dimensional position of the marker, an image obtained from the second optical imaging means, and the second optical imaging means and the detection means Based on the above, the three-dimensional position of the detection means is calculated, and the image creation means performs the reconstruction calculation process using the three-dimensional position of the irradiation means and the detection means calculated by the calculation means. The marker is 3 It is characterized in that at least.

［作用・効果］請求項２に記載の発明によれば、第１光学撮像手段と第２光学撮像手段とは、それぞれ照射手段または検出手段との相対的な位置関係が一定となる位置に設けられている。すなわち、移動手段等の外力を受けても、たわみ等が発生せず、両者の相対的な位置関係が変位することがないように第１光学撮像手段と第２光学撮像手段が設置されている。これら第１光学撮像手段と第２光学撮像手段とによって、所定のマーカを検知する。そして、第１光学撮像手段及び照射手段の間の相対的な位置関係と、第２光学撮像手段及び検出手段の間の相対的な位置関係と、マーカの３次元位置とを考慮することで、算定手段は、第１光学撮像手段と第２光学撮像手段との検知結果に基づいて、照射手段と検出手段との３次元位置を正確に算定することができる。 [Operation / Effect] According to the invention described in claim 2 , the first optical imaging means and the second optical imaging means are provided at positions where the relative positional relationship between the irradiation means and the detection means is constant. It has been. In other words, the first optical imaging means and the second optical imaging means are installed so that even if an external force from the moving means or the like is applied, no deflection or the like occurs and the relative positional relationship between the two does not change. . A predetermined marker is detected by the first optical imaging means and the second optical imaging means . And by considering the relative positional relationship between the first optical imaging means and the irradiation means, the relative positional relationship between the second optical imaging means and the detection means, and the three-dimensional position of the marker , The calculation means can accurately calculate the three-dimensional positions of the irradiation means and the detection means based on the detection results of the first optical imaging means and the second optical imaging means .

さらに、第１、第２光学撮像手段は、被検体の投影像の一群を得る際、各投影像が得られる時点ごとにマーカを検知する。マーカは所定の位置に配置されている。これにより、投影像を取得する各時点の照射手段及び検出手段の３次元位置を、推定することなく、直接算定しているので常に正確である。よって、照射手段または検出手段の軌道が偶発的にずれる場合や、軌道が経時的に変化してしまう場合であっても、照射手段および検出手段の正確な３次元位置を得ることができる。そして、得られた３次元位置を再構成演算処理に用いることで、画像作成手段はより厳密な校正を常に行うことができる。したがって、作成される断層画像や３次元画像の画質が劣化することがない。 Furthermore, when obtaining a group of projection images of the subject, the first and second optical imaging means detect a marker at each time point when each projection image is obtained. The marker is arranged at a predetermined position. As a result, the three-dimensional positions of the irradiation means and the detection means at each time point at which the projection image is acquired are directly calculated without being estimated, and thus are always accurate. Therefore, even when the trajectory of the irradiating means or the detecting means is accidentally shifted or the trajectory changes with time, it is possible to obtain accurate three-dimensional positions of the irradiating means and the detecting means. Then, by using the obtained three-dimensional position for the reconstruction calculation process, the image creating means can always perform more strict calibration. Therefore, the image quality of the created tomographic image or three-dimensional image does not deteriorate.

また、第１光学撮像手段と第２光学撮像手段とからマーカの画像が取得される。算定手段は、これらの画像から各光学撮像手段とマーカとの間の相対的な位置関係を求めることができる。そして、これらの位置関係について、マーカの３次元位置を考慮することで、各光学撮像手段の３次元位置が求められる。さらに、各光学撮像手段と照射手段、または検出手段との相対的な位置関係を考慮すると、照射手段及び検出手段の３次元位置を算定することができる。 In addition, a marker image is acquired from the first optical imaging unit and the second optical imaging unit. The calculation means can obtain the relative positional relationship between each optical imaging means and the marker from these images. And about these positional relationships, the three-dimensional position of each optical imaging means is calculated | required by considering the three-dimensional position of a marker. Furthermore, considering the relative positional relationship between each optical imaging means and the irradiation means or the detection means, the three-dimensional positions of the irradiation means and the detection means can be calculated.

また、マーカが３点以上であれば、照射手段及び検出手段の３次元位置を能率よく算定することができる。 Moreover, if there are three or more markers, the three-dimensional positions of the irradiation means and the detection means can be calculated efficiently.

上述した各発明において、前記各光学撮像手段は、それぞれ複数であることが好ましい。各光学撮像手段は、両眼視の手法を採用して、照射手段及び検出手段の３次元位置を容易に算定することができる。

 In each of the above-described inventions, it is preferable that there are a plurality of optical imaging means. Each optical imaging means can easily calculate the three-dimensional positions of the irradiation means and the detection means by adopting a binocular vision method.

なお、本明細書は、次のような断層撮影装置に係る発明も開示している。   The present specification also discloses an invention relating to the following tomographic apparatus.

（１）電磁波を被検体に照射する照射手段と、前記被検体を透過する電磁波を検出する検出手段と、前記照射手段および前記検出手段を互いに連動して移動させる移動手段と、前記移動手段により移動される前記検出手段から得られた投影像の一群に基づいて再構成演算処理を行い、断層像または／および３次元画像を作成する画像作成手段とを備えた断層撮影装置において、固定的に設置されて、前記照射手段及び前記検出手段の光学像を撮像する第４光学撮像手段と、前記第４光学撮像手段の３次元位置と、前記第４光学撮像手段から得られた画像とに基づいて、前記照射手段及び前記検出手段の３次元位置を算定する算定手段とを備え、前記画像作成手段は、前記算定手段により算定された前記照射手段及び前記検出手段の３次元位置を用いて前記再構成演算処理を行うことを特徴とする断層撮影装置。   (1) Irradiation means for irradiating a subject with electromagnetic waves, detection means for detecting electromagnetic waves transmitted through the subject, movement means for moving the irradiation means and the detection means in conjunction with each other, and the movement means In a tomography apparatus comprising a tomographic image and / or an image creating means for creating a three-dimensional image based on a group of projection images obtained from the detection means being moved, Based on a fourth optical imaging unit that is installed and images optical images of the irradiation unit and the detection unit, a three-dimensional position of the fourth optical imaging unit, and an image obtained from the fourth optical imaging unit. Calculating means for calculating a three-dimensional position of the irradiating means and the detecting means, and the image creating means includes a three-dimensional position of the irradiating means and the detecting means calculated by the calculating means. Tomography apparatus characterized by performing said reconstruction operation process using.

前記（１）に記載の発明によれば、第４光学撮像手段のみから得られる画像に基づいて、直接、照射手段及び検出手段の３次元位置を算定することができる。よって、光学撮像手段の種類を減らすことができる。また、マーカを省くことができる。よって、断層撮影装置の構成を簡略化することができる。   According to the invention described in (1), the three-dimensional positions of the irradiation unit and the detection unit can be directly calculated based on an image obtained only from the fourth optical imaging unit. Therefore, the types of optical imaging means can be reduced. Also, the marker can be omitted. Therefore, the configuration of the tomography apparatus can be simplified.

（２）前記（１）に記載の断層撮影装置において、前記第４光学撮像手段は複数であることを特徴とする断層撮影装置。   (2) The tomographic apparatus according to (1), wherein a plurality of the fourth optical imaging units are provided.

前記（２）に記載の発明によれば、第４光学撮像手段は、両眼視の手法を採用して、照射手段及び検出手段の３次元位置を容易に算定することができる。   According to the invention as described in said (2), the 4th optical imaging means can calculate the three-dimensional position of an irradiation means and a detection means easily by employ | adopting the method of binocular vision.

この発明に係る断層撮影装置によれば、照射手段または検出手段が移動する軌道が偶発的にずれた場合や、軌道が経時的に変化してしまう場合であっても、照射手段及び検出手段の３次元位置を常に正確に取得することができる。そして、この３次元位置を再構成演算処理に用いるので、より厳密な校正を行うことができる。しがたって、照射手段または検出手段の軌道のずれや変化が生じても、作成される断層画像や３次元画像の画質の劣化を抑えることができる。   According to the tomographic apparatus according to the present invention, even if the trajectory along which the irradiation means or the detection means moves is accidentally shifted or the trajectory changes over time, the irradiation means and the detection means The three-dimensional position can always be obtained accurately. Since this three-dimensional position is used for the reconstruction calculation process, more rigorous calibration can be performed. Therefore, even if a deviation or change in the trajectory of the irradiation unit or the detection unit occurs, it is possible to suppress deterioration of the image quality of the created tomographic image or three-dimensional image.

以下、図面を参照してこの発明の実施例１を説明する。
図１は、実施例１に係る断層撮影装置を示す全体構成図である。この断層撮影装置は、被検体Ｍの投影像を得る撮影部１と、この撮影部１を制御する撮影制御部３と、得られた投影像を処理して断層像または／および３次元画像を作成する画像処理部５と、この断層像等を表示するモニタ７とに大きく分けられる。 Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall configuration diagram illustrating the tomography apparatus according to the first embodiment. The tomography apparatus includes an imaging unit 1 that obtains a projection image of a subject M, an imaging control unit 3 that controls the imaging unit 1, and a tomogram or / and a three-dimensional image obtained by processing the obtained projection image. The image processing unit 5 to be created and a monitor 7 for displaying the tomographic image and the like are roughly divided.

撮影部１は、被検体Ｍを載置する天板１１と、被検体ＭにＸ線を照射するＸ線管１２と、被検体Ｍを挟んで、Ｘ線管１２と対向するように配置されて、被検体Ｍを透過するＸ線を検出するフラットパネル型Ｘ線検出器（以下、「ＦＰＤ」と略記する）１３と、Ｘ線管１２及びＦＰＤ１３をその両端部に保持するＣ字状アーム１４と、Ｃ字状アーム１４を懸垂支持する支持部１５とを備える。この支持部１５は、天板１１の長手方向を向いた水平方向の軸ＲＡを中心にＣ字状アーム１４を回転駆動する。これにより、Ｘ線管１２及びＦＰＤ１３も、Ｃ字状アーム１４と連動して移動する。なお、Ｃ字状アーム１４については、その形状は「Ｃ」字状に限らず、「Ｕ」字状等公知の形状を含む。また、Ｘ線管１２とＦＰＤ１３とは、それぞれこの発明における照射手段と検出手段とに相当する。さらに、Ｃ字状アーム１４は、この発明における移動手段に相当する。   The imaging unit 1 is disposed so as to face the X-ray tube 12 with the subject M sandwiched between the top plate 11 on which the subject M is placed, the X-ray tube 12 that irradiates the subject M with X-rays, and the subject M. A flat panel X-ray detector (hereinafter abbreviated as “FPD”) 13 that detects X-rays transmitted through the subject M, and a C-shaped arm that holds the X-ray tube 12 and the FPD 13 at both ends thereof. 14 and a support portion 15 that suspends and supports the C-shaped arm 14. The support portion 15 rotationally drives the C-shaped arm 14 about a horizontal axis RA facing the longitudinal direction of the top plate 11. Thereby, the X-ray tube 12 and the FPD 13 also move in conjunction with the C-shaped arm 14. The shape of the C-shaped arm 14 is not limited to a “C” shape, and includes a known shape such as a “U” shape. The X-ray tube 12 and the FPD 13 correspond to the irradiation means and the detection means in the present invention, respectively. Further, the C-shaped arm 14 corresponds to the moving means in the present invention.

また、Ｃ字状アーム１４の弧の略中央部であって内側には、監視板Ｐが設けられている。Ｃ字状アーム１４が回転駆動されると、この監視板Ｐも連動して移動する。   A monitoring plate P is provided on the inner side of the arc of the C-shaped arm 14. When the C-shaped arm 14 is driven to rotate, the monitoring plate P also moves in conjunction with it.

図２は、監視板の正面図の一例である。図示するように、この監視板Ｐには、３個の円形状のマーカｍ１、ｍ２、ｍ３（特に区別する必要がないときは、「マーカｍ」と総称する）が描かれている。なお、マーカｍは、後述するＣＣＤカメラで撮像されるものであり、Ｘ線を照射するものでない。よって、マーカｍは、視認できればよい。また、マーカｍの形状は球等の立体形状であることを要しない。   FIG. 2 is an example of a front view of the monitoring board. As shown in the figure, on this monitoring plate P, three circular markers m1, m2, and m3 (generally referred to as “marker m” when there is no need to distinguish them) are drawn. The marker m is picked up by a CCD camera, which will be described later, and does not emit X-rays. Therefore, the marker m only needs to be visually recognized. Further, the shape of the marker m does not need to be a three-dimensional shape such as a sphere.

さらに、Ｘ線管１２の両側端部には、それぞれ第１カメラ１６ａ、１６ｂ（以下では、特に区別する必要がないときは「第１カメラ１６」と総称する）が設置されている。同様に、ＦＰＤ１３の両側端部にもそれぞれ第２カメラ１７ａ、１７ｂ（特に区別する必要がないときは「第２カメラ１７」と総称する）が設置されている。また、Ｃ字状アーム１４や天板１１等とは別体に、固定的に第３カメラ１８ａ、１８ｂ（特に区別する必要がないときは「第３カメラ１８」と総称する）が設置されている。   Further, first cameras 16a and 16b (hereinafter collectively referred to as “first camera 16” when there is no need to distinguish between them) are respectively installed at both end portions of the X-ray tube 12. Similarly, second cameras 17a and 17b (generally referred to as “second camera 17” when there is no need to distinguish between them) are also installed at both end portions of the FPD 13 respectively. In addition, third cameras 18a and 18b (generally referred to as “third camera 18” when there is no need to distinguish between them) are fixedly provided separately from the C-shaped arm 14 and the top plate 11 and the like. Yes.

このような配置とすることで、第１カメラ１６及びＸ線管１２の間の相対的な位置関係は常に一定である。すなわち、Ｃ字状アーム１４の回転駆動のような外力が加わっても、第１カメラ１６及びＸ線管１２の間には機械的なたわみ等が生じることがない。言い換えれば、両者間の相対的な位置関係は変位することなく、常に一定である。同様に、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係も常に一定である。また、第３カメラ１８の場合は、その３次元位置が、Ｃ字状アーム１４等の可動部の動作とまったく関係なく、常に一定である。   With such an arrangement, the relative positional relationship between the first camera 16 and the X-ray tube 12 is always constant. That is, even when an external force such as rotational driving of the C-shaped arm 14 is applied, no mechanical deflection or the like occurs between the first camera 16 and the X-ray tube 12. In other words, the relative positional relationship between the two is always constant without being displaced. Similarly, the relative positional relationship between the second camera 17 and the FPD 13 is always constant. In the case of the third camera 18, the three-dimensional position is always constant irrespective of the operation of the movable part such as the C-shaped arm 14 or the like.

第１、第２、第３カメラ１６、１７、１８は、それぞれＣＣＤカメラであり、固体撮像素子であるＣＣＤ（Charge Coupled Device）と電子シャッターやレンズなどから構成されている。また、各カメラ１６、１７、１８は、監視板Ｐを撮像視野に入れるように撮像方向を調節して配置されている。また、第３カメラ１８は、Ｃ字状アーム１４が回転しても被検体Ｍの影に隠れることなく、監視板Ｐのマーカｍの光学像を撮像できるように、配置されている。なお、第１カメラ１６と第２カメラ１７と第３カメラ１８とは、それぞれこの発明における第１光学撮像手段と第２光学撮像手段と第３光学撮像手段とに相当する。   The first, second, and third cameras 16, 17, and 18 are CCD cameras, respectively, and include a CCD (Charge Coupled Device) that is a solid-state imaging device, an electronic shutter, a lens, and the like. Further, the cameras 16, 17, and 18 are arranged by adjusting the imaging direction so that the monitoring plate P enters the imaging field of view. Further, the third camera 18 is arranged so as to capture an optical image of the marker m on the monitoring plate P without being hidden by the shadow of the subject M even when the C-shaped arm 14 rotates. The first camera 16, the second camera 17, and the third camera 18 correspond to the first optical imaging means, the second optical imaging means, and the third optical imaging means in this invention, respectively.

撮影制御部３は、Ｘ線管１２によるＸ線の照射や、ＦＰＤ１３によるＸ線の検出や、Ｘ線管１２及びＦＰＤ１３の移動を制御する。   The imaging control unit 3 controls X-ray irradiation by the X-ray tube 12, X-ray detection by the FPD 13, and movement of the X-ray tube 12 and the FPD 13.

画像処理部５は、投影像収集部２１と画像収集部２３と３次元位置算定部２５と再構成演算部２７と保存部２９とを備えている。なお、係る画像処理部５は、所定のプログラムを読み出して実行する中央演算処理装置（ＣＰＵ）や、各種情報を記憶するＲＡＭ（Random-Access Memory）や固定ディスク等の記憶媒体等で実現される。   The image processing unit 5 includes a projection image collection unit 21, an image collection unit 23, a three-dimensional position calculation unit 25, a reconstruction calculation unit 27, and a storage unit 29. The image processing unit 5 is realized by a central processing unit (CPU) that reads and executes a predetermined program, a RAM (Random-Access Memory) that stores various information, a storage medium such as a fixed disk, and the like. .

投影像収集部２１は、ＦＰＤ１３から投影像を収集する。画像収集部２３は、各カメラ１６、１７、１８から画像を収集する。なお、画像収集部２３とは、投影像が得られる各時点において画像を取得するように、投影像収集部２１と同期している。このため、本実施例では、投影像収集部２１及びＦＰＤ１３が、撮影制御部３と連携して動作するように構成されている。   The projection image collection unit 21 collects projection images from the FPD 13. The image collection unit 23 collects images from the cameras 16, 17, and 18. The image collection unit 23 is synchronized with the projection image collection unit 21 so as to acquire an image at each time point when the projection image is obtained. For this reason, in this embodiment, the projection image collection unit 21 and the FPD 13 are configured to operate in cooperation with the imaging control unit 3.

３次元位置算定部２５は、記憶媒体に第１カメラ１６及びＸ線管１２の間の相対的な位置関係と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係と、第３カメラ１８の３次元位置とを記憶している。この記憶媒体から読み出す位置関係及び３次元位置と、画像収集部２３が収集した各画像とに基づいて、Ｘ線管１２とＦＰＤ１３との３次元位置を算定する。なお、３次元位置算定部２５は、この発明における算定手段に相当する。   The three-dimensional position calculation unit 25 includes a relative positional relationship between the first camera 16 and the X-ray tube 12 on the storage medium, a relative positional relationship between the second camera 17 and the FPD 13, and a third camera 18. Are stored. The three-dimensional positions of the X-ray tube 12 and the FPD 13 are calculated based on the positional relationship and the three-dimensional position read from the storage medium and each image collected by the image collecting unit 23. The three-dimensional position calculation unit 25 corresponds to the calculation means in this invention.

再構成演算部２７は、これらＸ線管１２及びＦＰＤ１３の３次元位置と、投影像の一群とに基づいて、断層像、あるいは３次元画像を作成する。保存部２９では、再構成演算部２７から得られた断層像等を保存する。そして、適宜操作者の指示等に従い、モニタ７に断層像等を表示する。再構成演算部２７は、この発明における画像作成手段に相当する。   The reconstruction calculation unit 27 creates a tomographic image or a three-dimensional image based on the three-dimensional positions of the X-ray tube 12 and the FPD 13 and a group of projection images. The storage unit 29 stores the tomographic image and the like obtained from the reconstruction calculation unit 27. Then, a tomographic image or the like is displayed on the monitor 7 in accordance with the operator's instruction as appropriate. The reconstruction calculation unit 27 corresponds to the image creation means in this invention.

次に、図３を参照して、実施例１に係る断層撮影装置の動作について説明する。   Next, the operation of the tomography apparatus according to the first embodiment will be described with reference to FIG.

＜ステップＳ１＞ 被検体を撮影する
撮影制御部３の制御に従い、Ｘ線管１２が被検体ＭにＸ線を照射する。ＦＰＤ１３は、被検体Ｍを透過したＸ線を検出し、投影像を得る。 <Step S <b>1> Imaging the Subject The X-ray tube 12 irradiates the subject M with X-rays according to the control of the imaging control unit 3. The FPD 13 detects X-rays transmitted through the subject M and obtains a projection image.

被検体Ｍの投影像を得る際、第１、第２、第３カメラ１６、１７、１８は、投影像が得られる各時点におけるマーカｍの光学像をそれぞれ撮像し、画像を得る。   When obtaining a projection image of the subject M, the first, second, and third cameras 16, 17, and 18 respectively capture an optical image of the marker m at each time point when the projection image is obtained, and obtain an image.

＜ステップＳ２＞ 投影像を収集する
投影像収集部２１は、ＦＰＤ１３から投影像を受け取って収集する。 <Step S2> Collecting Projected Images The projected image collecting unit 21 receives and collects projected images from the FPD 13.

＜ステップＳ３＞ 画像を収集する
画像収集部２３は、第１、第２、第３カメラ１６、１７、１８から、それぞれ画像を受け取って収集する。 <Step S3> Collecting Images The image collecting unit 23 receives and collects images from the first, second, and third cameras 16, 17, and 18, respectively.

＜ステップＳ４＞ Ｘ線管及びＦＰＤの３次元位置を算定する
３次元位置算定部２５は、画像収集部２３から各画像を受け取る。また、３次元位置算定部２５が有する記憶媒体から、第１カメラ１６及びＸ線管１２の間の相対的な位置関係と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係と、および第３カメラ１８の３次元位置とを読み出す。そして、第１カメラ１６が得た各画像について、両眼視の手法により処理を行い、第１カメラ１６及びマーカｍの間の相対的な位置関係を求める。同様に、第２カメラ１７が得た各画像に基づいて、第２カメラ１７及びマーカｍの間の相対的な位置関係を求める。 <Step S <b>4> The three-dimensional position calculation unit 25 that calculates the three-dimensional positions of the X-ray tube and the FPD receives each image from the image collection unit 23. Further, from the storage medium included in the three-dimensional position calculation unit 25, the relative positional relationship between the first camera 16 and the X-ray tube 12, the relative positional relationship between the second camera 17 and the FPD 13, and The three-dimensional position of the third camera 18 is read out. Then, each image obtained by the first camera 16 is processed by a binocular viewing method to obtain a relative positional relationship between the first camera 16 and the marker m. Similarly, the relative positional relationship between the second camera 17 and the marker m is obtained based on each image obtained by the second camera 17.

また、第３カメラ１８が得た各画像と第３カメラ１８の３次元位置とに基づいて、マーカｍの３次元位置を求める。   Further, the three-dimensional position of the marker m is obtained based on each image obtained by the third camera 18 and the three-dimensional position of the third camera 18.

第１カメラ１６及びマーカｍの間の相対的な位置関係に、マーカｍの３次元位置を与えて、第１カメラ１６の３次元位置を求める。さらに、求めた第１カメラ１６の３次元位置を、第１カメラ１６及びＸ線管１２の間の相対的な位置関係に与えて、Ｘ線管１２の３次元位置を求める。   The three-dimensional position of the marker m is obtained by giving the three-dimensional position of the marker m to the relative positional relationship between the first camera 16 and the marker m. Further, the obtained three-dimensional position of the first camera 16 is given to the relative positional relationship between the first camera 16 and the X-ray tube 12 to obtain the three-dimensional position of the X-ray tube 12.

同様に、第２カメラ１７及びマーカｍの間の相対的な位置関係と、マーカｍの３次元位置とに基づいて、第２カメラ１７の３次元位置を求める。そして、第２カメラ１７の３次元位置と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係とに基づいて、ＦＰＤ１３の３次元位置を求める。   Similarly, the three-dimensional position of the second camera 17 is obtained based on the relative positional relationship between the second camera 17 and the marker m and the three-dimensional position of the marker m. Then, the three-dimensional position of the FPD 13 is obtained based on the three-dimensional position of the second camera 17 and the relative positional relationship between the second camera 17 and the FPD 13.

なお、３次元位置算定部２５は、このＸ線管１２とＦＰＤ１３との３次元位置について、投影像が得られた時点ごとに、一連の算定処理を繰り返す。   The three-dimensional position calculation unit 25 repeats a series of calculation processes for each three-dimensional position of the X-ray tube 12 and the FPD 13 every time a projection image is obtained.

＜ステップＳ５＞ 投影像と３次元位置に基づき、再構成演算処理を行う
再構成演算部２７は、投影像収集部２１が収集した投影像の一群を受け取る。また、３次元位置算定部２５からＸ線管１２とＦＰＤ１３との３次元位置を受け取る。そして、投影像と各３次元位置に基づいて、被検体Ｍに対する再構成演算処理を行い、被検体Ｍの任意の位置の断層像あるいは３次元ボリュームデータを作成する。 <Step S5> Based on the projection image and the three-dimensional position, the reconstruction calculation unit 27 that performs the reconstruction calculation process receives a group of projection images collected by the projection image collection unit 21. Further, the three-dimensional positions of the X-ray tube 12 and the FPD 13 are received from the three-dimensional position calculation unit 25. Based on the projection image and each three-dimensional position, reconstruction calculation processing is performed on the subject M, and a tomographic image or three-dimensional volume data of an arbitrary position of the subject M is created.

この３次元ボリュームデータを作成する一連の手順について、図４を参照しながら概説する。まず、この一群の撮影データを単純逆投影（単純バックプロジェクション：単純ＢＰ）して単純ＢＰ中間像を生成する。次に、この単純ＢＰ中間像を３次元フーリエ変換して、実空間データからフーリエ空間データに変換した３次元フーリエ分布像（図４には、３次元フーリエ空間座標で表示しているものに対応する）を生成する。次に、この３次元フーリエ分布像に対してフィルタリング処理を施す（｜ω｜フィルタリング（絶対値オメガフィルタリング）やローパスフィルタリング）。次に、フィルタリング処理を施した３次元フーリエ分布像を３次元逆フーリエ変換して、フーリエ空間データから実空間データに戻し、３次元ボリュームデータ（図４には、右端側に表示され、周方向に幾本かの破線が図示されている円柱状のものに対応する）が生成される。このようにして、関心領域の３次元ボリュームデータを生成する再構成が行なわれる。なお、この３次元ボリュームデータから任意の断層面を選択することで、選択した断層像が見られる（図４には、最右端に表示された厚みの薄い円柱状のものを見ているものに対応する）。上述したように、一旦、単純ＢＰ中間像を生成し、この単純ＢＰ中間像をフーリエ空間で所定のフィルタリング処理を施すという手法を、Ｆ（フーリエ）空間フィルタ法と呼ぶ。   A series of procedures for creating the three-dimensional volume data will be outlined with reference to FIG. First, a simple back projection (simple back projection: simple BP) is performed on the group of photographing data to generate a simple BP intermediate image. Next, this simple BP intermediate image is subjected to three-dimensional Fourier transform, and converted from real space data to Fourier space data, a three-dimensional Fourier distribution image (corresponding to the one displayed in three-dimensional Fourier space coordinates in FIG. 4). Generate). Next, filtering processing is performed on the three-dimensional Fourier distribution image (| ω | filtering (absolute value omega filtering) or low-pass filtering). Next, the filtered three-dimensional Fourier distribution image is subjected to three-dimensional inverse Fourier transform to return from the Fourier space data to the real space data. The three-dimensional volume data (displayed on the right end side in FIG. (Corresponding to a cylindrical shape in which several broken lines are shown). In this way, reconstruction is performed to generate three-dimensional volume data of the region of interest. By selecting an arbitrary tomographic plane from the three-dimensional volume data, the selected tomographic image can be seen (FIG. 4 shows a thin cylindrical shape displayed at the rightmost end. Corresponding). As described above, a method of once generating a simple BP intermediate image and subjecting the simple BP intermediate image to a predetermined filtering process in Fourier space is called an F (Fourier) spatial filter method.

ここで、単純ＢＰ中間像を生成するとき、図５に示すように、撮影された被検体Ｍの関心領域に３次元格子群Ｋを仮想的に設定する。そして、３次元格子群Ｋ内の格子点Ｊを選択して、ＦＰＤ１３上の点ＤPにおける検出データを、Ｘ線管１２と点ＤPとを結ぶ直線上にある格子点Ｊに逆投影する。 Here, when the simple BP intermediate image is generated, a three-dimensional lattice group K is virtually set in the region of interest of the subject M as shown in FIG. Then, by selecting the grid point J in 3-dimensional lattice K, the detection data at the point D P on FPD13, inversely projected onto the lattice point J in straight line connecting the X-ray tube 12. and the point D P .

ここで、ＦＰＤ１３上の点ＤPの座標は、Ｘ線管１２とＦＰＤ１３との３次元位置に基づき、格子点Ｊの位置から正確に求められる。 Here, the coordinates of a point D P on FPD13, based on the three-dimensional position of the X-ray tube 12 and FPD13, is accurately determined from the position of the grid point J.

また、点ＤPにおける検出データは、この点ＤPに最近接する例えば４点ｄ１〜ｄ４の検出データを加重平均して求める。そして、このような検出データをいろいろな角度から得て、格子点に累算することで、その格子点について逆投影を行うことができる。そして、３次元格子群Ｋの残りの格子点について、前記と同様にして逆投影を行い、さらに、各位置ごとにこれと同様の逆投影を行うことで、単純ＢＰ中間像が生成される。なお、予め、被検体Ｍの撮影像にボケ防止のフィルタ処理等を施してもよい。 The detection data at the point D P obtains the detection data of recent contact with for example four points d1~d4 this point D P weighted average of. Then, by obtaining such detection data from various angles and accumulating at the lattice points, back projection can be performed on the lattice points. Then, the remaining lattice points of the three-dimensional lattice group K are back-projected in the same manner as described above, and further, the same back-projection is performed at each position to generate a simple BP intermediate image. Note that a blur prevention filter process or the like may be applied to the captured image of the subject M in advance.

＜ステップＳ６＞ 断層像等の保存、表示を行う
その後、作成した被検体Ｍの任意の位置の断層像あるいは３次元ボリュームデータを保存部２９に記憶保存し、要求に応じて、適宜、モニタ７に出力して表示する（Ｓ７）。 <Step S6> Storage and display of tomographic image, etc. Thereafter, the generated tomographic image or three-dimensional volume data of an arbitrary position of the subject M is stored and stored in the storage unit 29, and the monitor 7 is appropriately stored as required. Is output and displayed (S7).

このように、実施例１に係る断層撮影装置によれば、第１、第２カメラ１６、１７は、マーカｍの光学像を撮像する。３次元位置算定部２５は、マーカｍの３次元位置を考慮することで、第１、第２カメラ１６、１７から得られた画像に基づいて、第１、第２カメラ１６、１７の各３次元位置を算定することができる。さらに、第１カメラ１６が、Ｘ線管１２との間の相対的な位置関係が一定となる位置に設けられており、第２カメラ１７が、ＦＰＤ１３との間の相対的な位置関係が一定となる位置に設けられている。よって、３次元位置算定部２５は、これらの相対的な位置関係を考慮することで、Ｘ線管１２とＦＰＤ１３との各３次元位置を正確に算定することができる。   As described above, according to the tomography apparatus according to the first embodiment, the first and second cameras 16 and 17 capture an optical image of the marker m. The three-dimensional position calculation unit 25 considers the three-dimensional position of the marker m, and based on the images obtained from the first and second cameras 16 and 17, each of the first and second cameras 16 and 17. The dimension position can be calculated. Furthermore, the first camera 16 is provided at a position where the relative positional relationship with the X-ray tube 12 is constant, and the second camera 17 has a constant relative positional relationship with the FPD 13. It is provided at the position. Therefore, the three-dimensional position calculation unit 25 can accurately calculate the three-dimensional positions of the X-ray tube 12 and the FPD 13 by considering these relative positional relationships.

また、本実施例に係るマーカの３次元位置は変位する。しかし、固定的に設置される第３カメラ１８がマーカの光学像を撮像することにより、３次元位置算定部２５は、マーカｍの３次元位置を正確に求めることができる。   Further, the three-dimensional position of the marker according to the present embodiment is displaced. However, the third camera 18 fixedly picks up the optical image of the marker, so that the three-dimensional position calculation unit 25 can accurately determine the three-dimensional position of the marker m.

また、第１、第２、第３カメラ１６、１７、１８は、被検体Ｍの撮影において、各投影像の取得の時点におけるマーカｍの光学像を撮像する。そして、３次元位置算定部２５は、Ｘ線管１２とＦＰＤ１３との３次元位置を推定することなく、直接検知して算定する。したがって、Ｘ線管１２とＦＰＤ１３との３次元位置を常に正確に算定することができる。よって、Ｃ字状アーム１４のたわみ等によってＸ線管１２とＦＰＤ１３の軌道が偶発的にずれた場合であっても、３次元位置算定部２５は正確にＸ線管１２及びＦＰＤ１３の３次元位置を取得することができる。また、Ｘ線管１２とＦＰＤ１３の軌道が経時的に変化してしまっても、被検体Ｍの撮影の都度（撮影と同時に）、３次元位置算定部２５が算定するので、Ｘ線管１２及びＦＰＤ１３の３次元位置は常に正確である。   In addition, the first, second, and third cameras 16, 17, and 18 capture an optical image of the marker m at the time of acquiring each projection image when the subject M is captured. The three-dimensional position calculation unit 25 directly detects and calculates the three-dimensional position between the X-ray tube 12 and the FPD 13 without estimating the three-dimensional position. Therefore, the three-dimensional positions of the X-ray tube 12 and the FPD 13 can always be accurately calculated. Therefore, even when the trajectories of the X-ray tube 12 and the FPD 13 are accidentally shifted due to the deflection of the C-shaped arm 14 or the like, the three-dimensional position calculation unit 25 accurately determines the three-dimensional positions of the X-ray tube 12 and the FPD 13. Can be obtained. Even if the trajectories of the X-ray tube 12 and the FPD 13 change with time, the three-dimensional position calculation unit 25 calculates each time the subject M is imaged (simultaneously with the imaging). The three-dimensional position of the FPD 13 is always accurate.

また、このように構成することで、被検体Ｍの撮影の前に校正ファントムを撮影して、予めＸ線管１２及びＦＰＤ１３の３次元位置を取得することを要しない。   Further, with this configuration, it is not necessary to capture the calibration phantom before imaging the subject M and acquire the three-dimensional positions of the X-ray tube 12 and the FPD 13 in advance.

また、第１、第２、第３カメラ１６、１７、１８はそれぞれ２台あるので、マーカｍとの相対的な位置関係やマーカｍの３次元位置を、両眼視の手法により容易に求めることができる。   Further, since there are two first, second, and third cameras 16, 17, and 18, the relative positional relationship with the marker m and the three-dimensional position of the marker m can be easily obtained by a binocular vision method. be able to.

監視板Ｐ上に配されるマーカｍは３点であるので、３次元位置算定部２５は、Ｘ線管１２及びＦＰＤ１３の３次元位置を能率よく算定することができる。   Since the markers m arranged on the monitoring plate P are three points, the three-dimensional position calculation unit 25 can efficiently calculate the three-dimensional positions of the X-ray tube 12 and the FPD 13.

また、支持部１５による回転駆動により、Ｃ字状アーム１３は、そのＣ字状の円弧の略中央部を貫く軸ＲＡを中心に回転移動する。そして、マーカｍを配する監視板Ｐは、Ｃ字状アーム１４の回転軸ＲＡ近傍であって、Ｘ線管１２及びＦＰＤ１３に対向するように、Ｃ字状アーム１４の円弧の内側に設置されている。よって、Ｃ字状アーム１４が回転移動した場合であっても、マーカｍの変位量は比較的少ない。よって、Ｘ線管１２の両側端部に設けらる第１カメラ１６、および、ＦＰＤ１３の両側端部に設けられる第２カメラ１７は、常に、マーカｍの光学像を撮像視野に容易に入れることができる。   Further, by the rotational drive by the support portion 15, the C-shaped arm 13 rotates around an axis RA that passes through a substantially central portion of the C-shaped arc. The monitoring plate P on which the marker m is arranged is installed in the vicinity of the rotation axis RA of the C-shaped arm 14 and inside the arc of the C-shaped arm 14 so as to face the X-ray tube 12 and the FPD 13. ing. Therefore, even if the C-shaped arm 14 rotates, the amount of displacement of the marker m is relatively small. Therefore, the first camera 16 provided at both ends of the X-ray tube 12 and the second camera 17 provided at both ends of the FPD 13 always easily put the optical image of the marker m in the imaging field. Can do.

次に、この発明の実施例２を説明する。
図６は、この実施例２に係る断層撮影装置を示す全体構成図である。なお、実施例１と同じ構成については同符号を付すことで詳細な説明を省略する。 Next, a second embodiment of the present invention will be described.
FIG. 6 is an overall configuration diagram showing the tomography apparatus according to the second embodiment. In addition, about the same structure as Example 1, detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol.

この断層撮影装置は、被検体Ｍの投影像を得る撮影部２と、この撮影部２を制御する撮影制御部３と、得られた投影像を処理して断層象等を作成する画像処理部６と、この断層像等を表示するモニタ７とに大きく分けられる。   The tomography apparatus includes an imaging unit 2 that obtains a projection image of a subject M, an imaging control unit 3 that controls the imaging unit 2, and an image processing unit that processes the obtained projection image to create a tomogram or the like. 6 and a monitor 7 for displaying this tomographic image or the like.

撮影部２において、監視板Ｐは、Ｃ字状アーム１４や天板１１等とは別体に、固定的に設置されている。監視板Ｐ上に配される３点のマーカｍ１〜ｍ３は、実施例１と同様である。よって、マーカｍの３次元位置は、Ｃ字状アーム１４等の可動部の動作とまったく関係なく、常に一定である。   In the imaging unit 2, the monitoring plate P is fixedly installed separately from the C-shaped arm 14, the top plate 11, and the like. The three markers m1 to m3 arranged on the monitoring plate P are the same as in the first embodiment. Therefore, the three-dimensional position of the marker m is always constant regardless of the operation of the movable part such as the C-shaped arm 14.

このため、第１カメラ１６と第２カメラ１７は、それぞれ撮像視野に監視板Ｐをいれるように、第１実施例とは異なる撮像方向に向けて、設置されている。なお、撮像部２は、第１実施例で説明した第３カメラ１８を備えていない。   For this reason, the first camera 16 and the second camera 17 are installed in an imaging direction different from that of the first embodiment so that the monitoring plate P is placed in the imaging field of view. Note that the imaging unit 2 does not include the third camera 18 described in the first embodiment.

画像処理部６は、投影像収集部２１と画像収集部２４と３次元位置算定部２６と再構成演算部２７と保存部２９とを備えている。ここで、第１実施例の対応する構成と異なる画像収集部２４と３次元位置算定部２６とについて説明する。   The image processing unit 6 includes a projection image collection unit 21, an image collection unit 24, a three-dimensional position calculation unit 26, a reconstruction calculation unit 27, and a storage unit 29. Here, the image collection unit 24 and the three-dimensional position calculation unit 26 different from the corresponding configurations of the first embodiment will be described.

画像収集部２４は、マーカｍの光学像を撮像する各カメラ１６、１７から得られる画像を収集する。   The image collection unit 24 collects images obtained from the cameras 16 and 17 that capture an optical image of the marker m.

３次元位置算定部２６は、記憶媒体に第１カメラ１６及びＸ線管１２の間の相対的な位置関係と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係と、マーカｍの３次元位置とを記憶している。この記憶媒体から読み出す位置関係及び３次元位置と、画像収集部２４が収集した各画像とに基づいて、Ｘ線管１２とＦＰＤ１３との３次元位置を算定する。なお、３次元位置算定部２６は、この発明における算定手段に相当する。   The three-dimensional position calculation unit 26 stores the relative positional relationship between the first camera 16 and the X-ray tube 12 on the storage medium, the relative positional relationship between the second camera 17 and the FPD 13, and the marker m 3. The dimension position is memorized. The three-dimensional positions of the X-ray tube 12 and the FPD 13 are calculated based on the positional relationship and the three-dimensional position read from the storage medium and each image collected by the image collecting unit 24. The three-dimensional position calculation unit 26 corresponds to calculation means in the present invention.

具体的には、以下のような処理により算定する。   Specifically, it is calculated by the following process.

すなわち、３次元位置算定部２６は、画像収集部２４から各画像を受け取る。また、３次元位置算定部２６が有する記憶媒体から、第１カメラ１６及びＸ線管１２の間の相対的な位置関係と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係と、マーカｍの３次元位置とを読み出す。そして、第１カメラ１６から得られた各画像について、両眼視の手法により処理を行い、第１カメラ１６及びマーカｍの間の相対的な位置関係を求める。同様に、第２カメラ１７から得られた各画像に基づいて、第２カメラ１７及びマーカｍの間の相対的な位置関係を求める。   That is, the three-dimensional position calculation unit 26 receives each image from the image collection unit 24. In addition, the relative positional relationship between the first camera 16 and the X-ray tube 12, the relative positional relationship between the second camera 17 and the FPD 13, and the marker Read out the three-dimensional position of m. Then, each image obtained from the first camera 16 is processed by a binocular technique to obtain a relative positional relationship between the first camera 16 and the marker m. Similarly, the relative positional relationship between the second camera 17 and the marker m is obtained based on each image obtained from the second camera 17.

求めた第１カメラ１６及びマーカｍの間の相対的な位置関係に、マーカｍの３次元位置を与えて、第１カメラ１６の３次元位置を求める。さらに、求めた第１カメラ１６の３次元位置を、第１カメラ１６及びＸ線管１２の間の相対的な位置関係に与えて、Ｘ線管１２の３次元位置を算定する。   The three-dimensional position of the marker m is given to the relative positional relationship between the obtained first camera 16 and the marker m, and the three-dimensional position of the first camera 16 is obtained. Further, the obtained three-dimensional position of the first camera 16 is given to the relative positional relationship between the first camera 16 and the X-ray tube 12 to calculate the three-dimensional position of the X-ray tube 12.

同様に、第２カメラ１７及びマーカｍの間の相対的な位置関係と、マーカｍの３次元位置とに基づいて、第２カメラ１７の３次元位置を求める。そして、第２カメラ１７の３次元位置と、第２カメラ１７及びＦＰＤ１３の間の相対的な位置関係とに基づいて、ＦＰＤ１３の３次元位置を算定する。   Similarly, the three-dimensional position of the second camera 17 is obtained based on the relative positional relationship between the second camera 17 and the marker m and the three-dimensional position of the marker m. Then, the three-dimensional position of the FPD 13 is calculated based on the three-dimensional position of the second camera 17 and the relative positional relationship between the second camera 17 and the FPD 13.

なお、３次元位置算定部２６は、このＸ線管１２とＦＰＤ１３との３次元位置について、投影像が得られた時点ごとに、一連の算定処理をする。   The three-dimensional position calculation unit 26 performs a series of calculation processes for the three-dimensional positions of the X-ray tube 12 and the FPD 13 at each time point when a projection image is obtained.

このように、実施例２に係る断層撮影装置によっても、実施例１と同様に、投影像が得られる各時点におけるＸ線管１２とＦＰＤ１３との３次元位置を常に正確に算定することができる。また、被検体Ｍの撮影前に、構成ファントムを撮影することを要しない。   As described above, the tomography apparatus according to the second embodiment can always accurately calculate the three-dimensional positions of the X-ray tube 12 and the FPD 13 at each time point when the projection image is obtained, as in the first embodiment. . Further, it is not necessary to photograph the constituent phantom before photographing the subject M.

さらに、実施例２にかかる断層撮影装置によれば、監視板Ｐを固定的に設置することで、マーカｍの３次元位置は変位せず、常に一定である。よって、マーカｍの３次元位置を求める処理や、そのための画像を取得するカメラ（例えば、実施例１で説明した第３カメラ１８）の設置を省略することができる。   Furthermore, according to the tomographic apparatus according to the second embodiment, the three-dimensional position of the marker m is not displaced and is always constant by fixing the monitoring plate P. Therefore, it is possible to omit the process of obtaining the three-dimensional position of the marker m and the installation of a camera (for example, the third camera 18 described in the first embodiment) that acquires an image for that purpose.

この発明は、上記実施形態に限られることはなく、下記のように変形実施することができる。   The present invention is not limited to the above-described embodiment, and can be modified as follows.

（１）上述した各実施例では、マーカｍの光学像を各カメラ１６、１７、１８が撮像する構成であったが、Ｘ線管１２とＦＰＤ１３との３次元位置を算定できるかぎり、適宜に設計変更できる。   (1) In each of the above-described embodiments, each camera 16, 17, and 18 captures an optical image of the marker m. However, as long as the three-dimensional positions of the X-ray tube 12 and the FPD 13 can be calculated, The design can be changed.

たとえば、Ｃ字状アーム１４や天板１１等とは別体に、固定的に設置される第４カメラを備えて、Ｘ線管１２及びＦＰＤ１３の光学像を直接撮像するように構成してもよい。このとき、３次元位置算定部２５（２６）は、第４カメラが得た画像と、第４カメラの３次元位置とに基づいてＸ線管１２及びＦＰＤ１３の３次元位置を直接的に算定することができる。また、かかる構成により、マーカｍを配する監視板Ｐやマーカｍの光学像を撮像する第１、第２、第３カメラ１６、１７、１８を省略することができる。また、マーカｍの３次元位置を求める処理も不要となる。   For example, a fourth camera that is fixedly installed may be provided separately from the C-shaped arm 14, the top plate 11, and the like, and the optical images of the X-ray tube 12 and the FPD 13 may be directly captured. Good. At this time, the three-dimensional position calculation unit 25 (26) directly calculates the three-dimensional positions of the X-ray tube 12 and the FPD 13 based on the image obtained by the fourth camera and the three-dimensional position of the fourth camera. be able to. Further, with this configuration, the monitoring plate P on which the marker m is arranged and the first, second, and third cameras 16, 17, and 18 that capture an optical image of the marker m can be omitted. Further, the process for obtaining the three-dimensional position of the marker m is not necessary.

（２）上述した各実施例では、各カメラ１６、１７、１８等は、それぞれ２台であった。しかし、各カメラの台数はこれに限らず、それぞれ３台以上であってもよいし、それぞれ１台でもよい。なお、１台の場合は、所定の撮像条件を満たすようにカメラを設置することで、３次元位置算定部２５（２６）は得られた画像から、Ｘ線管１２とＦＰＤ１３との３次元位置も算定することができる。   (2) In each of the above-described embodiments, there are two cameras 16, 17, 18, and the like. However, the number of each camera is not limited to this, and may be three or more, or one each. In the case of a single unit, the three-dimensional position calculation unit 25 (26) sets the three-dimensional positions of the X-ray tube 12 and the FPD 13 from the obtained image by installing a camera so as to satisfy a predetermined imaging condition. Can also be calculated.

（３）上述した各実施例では、第１、第２カメラ１６、１７は、Ｘ線管１２またはＦＰＤ１３の両側端部に設置する構成であった。しかし、第１、第２カメラ１６、１７の３次元位置がわかれば、Ｘ線管１２とＦＰＤ１３との３次元位置が算定できる限り適宜に設計変更できる。たとえば、Ｘ線管１２またはＦＰＤ１３と、Ｃ字状アーム１４との接合部に、第１、第２カメラ１６、１７を設置するようにしてもよい。   (3) In each of the above-described embodiments, the first and second cameras 16 and 17 are configured to be installed at both end portions of the X-ray tube 12 or the FPD 13. However, if the three-dimensional positions of the first and second cameras 16 and 17 are known, the design can be changed as appropriate as long as the three-dimensional positions of the X-ray tube 12 and the FPD 13 can be calculated. For example, the first and second cameras 16 and 17 may be installed at the joint between the X-ray tube 12 or the FPD 13 and the C-shaped arm 14.

（４）上述した各実施例では、各カメラ１６、１７、１８は、ＣＣＤカメラであった。しかし、例えばテレビカメラなど、マーカの光学像を撮像してその画像が得られる公知のカメラ、またはセンサに適宜に設計変更してもよい。さらには、マーカとの相対的な位置関係を検出することができれば、各カメラ１６、１７、１８のように光学像を撮像するセンサに限られない。たとえば、マーカに対して、特定の光や電波等を照射して、マーカとの位置関係を検知するセンサであってもよい。   (4) In each embodiment described above, each of the cameras 16, 17, and 18 is a CCD camera. However, the design may be appropriately changed to a known camera or a sensor that captures an optical image of a marker such as a television camera and obtains the image. Furthermore, as long as the relative positional relationship with the marker can be detected, the present invention is not limited to a sensor that captures an optical image, such as the cameras 16, 17, and 18. For example, a sensor that irradiates a marker with specific light, radio waves, or the like and detects a positional relationship with the marker may be used.

（５）上述した各実施例では、マーカｍが配される監視板Ｐは、Ｃ字状アーム１４の円弧の略中心付近に設置されるものであった。しかし、各カメラ１６、１７、１８がマーカｍの光学像を撮像できればよく、監視板Ｐの位置は適宜に設計変更することができる。   (5) In each of the above-described embodiments, the monitoring plate P on which the marker m is disposed is installed near the approximate center of the arc of the C-shaped arm 14. However, each camera 16, 17, and 18 need only be able to capture an optical image of the marker m, and the design of the position of the monitoring plate P can be changed as appropriate.

（６）上述した第１実施例では、マーカｍが配される監視板Ｐは、Ｃ字状アーム１４とともに移動するものであった。しかし、例えば支持部１５等が監視板Ｐを保持する等により、監視板Ｐを固定的に設置するように構成してもよい。これにより、マーカｍの３次元位置を求める処理や、そのために必要な画像を取得するカメラの設置を省略することができる。   (6) In the first embodiment described above, the monitoring plate P on which the marker m is arranged moves with the C-shaped arm 14. However, the monitoring plate P may be fixedly installed, for example, by the support unit 15 or the like holding the monitoring plate P. Thereby, it is possible to omit the process of obtaining the three-dimensional position of the marker m and the installation of a camera that acquires an image necessary for this.

（７）上述した各実施例では、軸ＲＡ周りに回転するようにＣ字状アーム１４を駆動する構成である。しかしながら、Ｘ線管１２及びＦＰＤ１３の軌道は、かかる駆動に応じたもののみに限定されない。たとえば、全周３６０°分回転する、いわゆるＣＴ装置のような軌道でも良い。また、軸ＲＡ以外の軸を中心にＣ字状アームを回転させてもよい。更に、投影位置によって回転軸からＸ線管１２またはＦＰＤ１３への距離が変化するような軌道、Ｘ線管１２とＦＰＤ１３とが一定の平面内に存在しないような軌道、あるいは、撮影毎にＣ字状アーム１４等のメカのがたつき等が原因で不連続な軌道でＸ線管１２とＦＰＤ１３とを変位させるものでも良い。また、Ｘ線管１２とＦＰＤ１３の軌道は、平行な二直線あるいはそれに順ずる軌道でも良い。要するに、複数の異なる方向から被検体Ｍの投影像が得られさえすれば、どのような軌道でも良い。   (7) In each of the above-described embodiments, the C-shaped arm 14 is driven to rotate around the axis RA. However, the trajectories of the X-ray tube 12 and the FPD 13 are not limited to those corresponding to such driving. For example, a track such as a so-called CT apparatus that rotates 360 ° around the entire circumference may be used. Further, the C-shaped arm may be rotated about an axis other than the axis RA. Furthermore, a trajectory in which the distance from the rotation axis to the X-ray tube 12 or the FPD 13 varies depending on the projection position, a trajectory in which the X-ray tube 12 and the FPD 13 do not exist within a certain plane, or a C-character for each imaging. For example, the X-ray tube 12 and the FPD 13 may be displaced in a discontinuous orbit due to the backlash of the mechanical arm 14 or the like. Further, the trajectory of the X-ray tube 12 and the FPD 13 may be two parallel straight lines or a trajectory that follows the parallel straight lines. In short, any trajectory may be used as long as projection images of the subject M can be obtained from a plurality of different directions.

（８）上記した各実施例では、Ｘ線を照射するＸ線管１２を備えているが、この発明としては、可視光、プラズマＸ線源からのＸ線、放射性同位元素からのガンマ線、電子ライラックからのＸ線照射する構成のものや、シンクロトロン軌道放射光源（ＳＯＲ）など、各種の電磁波を照射するものを用いることができる。   (8) In each of the above-described embodiments, the X-ray tube 12 for irradiating X-rays is provided. As the present invention, visible light, X-rays from a plasma X-ray source, gamma rays from radioisotopes, electrons A device that emits various electromagnetic waves, such as a configuration that emits X-rays from a lilac, or a synchrotron orbital radiation source (SOR) can be used.

（９）また、上記した各実施例では、検出手段として、ＦＰＤ１３を用いているが、この発明としては、イメージインテンシファイアや多列検出器などを用いるものでも良い。   (9) In each of the embodiments described above, the FPD 13 is used as the detection means. However, the present invention may use an image intensifier or a multi-row detector.

（１０）さらに、上記した各実施例では、撮影部１（２）は、Ｃ字状アーム１４によって保持することにより、Ｘ線管１２とＦＰＤ１３とを機械的に結合して構成されている。しかし、Ｘ線管１２とＦＰＤ１３とを互いに連動して移動させることができれば、Ｃ字状アーム１４を有する構成に限られない。たとえば、Ｘ線管１２とＦＰＤ１３とを個別に保持しつつ、共通の回転駆動軸に連結する等の構成により、Ｘ線管１２とＦＰＤ１３とを互いに連動して移動させても良い。また、Ｘ線管１２とＦＰＤ１３とを個別に保持しつつ、それぞれを個別に、かつ、相互に同期制御して回転駆動する構成としても良い。   (10) Further, in each of the above-described embodiments, the imaging unit 1 (2) is configured by mechanically coupling the X-ray tube 12 and the FPD 13 by being held by the C-shaped arm 14. However, the configuration having the C-shaped arm 14 is not limited as long as the X-ray tube 12 and the FPD 13 can be moved in conjunction with each other. For example, the X-ray tube 12 and the FPD 13 may be moved in conjunction with each other by a configuration in which the X-ray tube 12 and the FPD 13 are individually held and connected to a common rotational drive shaft. Further, the X-ray tube 12 and the FPD 13 may be held individually, and may be configured to be rotationally driven individually and synchronously with each other.

実施例１に係る断層撮影装置を示す全体構成図である。1 is an overall configuration diagram illustrating a tomography apparatus according to Embodiment 1. FIG. 監視板の正面図である。It is a front view of a monitoring board. 実施例１に係る断層撮影装置の動作を説明するフローチャートである。3 is a flowchart for explaining the operation of the tomography apparatus according to Embodiment 1; ３次元ボリュームデータを作成する手順を説明ための模式図である。It is a schematic diagram for demonstrating the procedure which produces three-dimensional volume data. 逆投影法を説明するための模式図である。It is a schematic diagram for demonstrating a back projection method. 実施例２に係る断層撮影装置を示す全体構成図である。3 is an overall configuration diagram illustrating a tomography apparatus according to Embodiment 2. FIG. 先行発明に係る断層撮影装置の全体構成図である。It is a whole block diagram of the tomography apparatus which concerns on prior invention. 先行発明に係る断層撮影装置の動作を説明するフローチャートである。It is a flowchart explaining operation | movement of the tomography apparatus which concerns on prior invention.

符号の説明Explanation of symbols

１２ …Ｘ線管
１３ …フラットパネル型Ｘ線検出器（ＦＰＤ）
１４ …Ｃ字状アーム
１６ａ、１６ｂ …第１カメラ
１７ａ、１７ｂ …第２カメラ
１８ａ、１８ｂ …第３カメラ
２５、２６ …３次元位置算定部
２７ …再構成演算部
Ｍ …被検体
ｍ …マーカ 12 ... X-ray tube 13 ... Flat panel X-ray detector (FPD)
DESCRIPTION OF SYMBOLS 14 ... C-shaped arm 16a, 16b ... 1st camera 17a, 17b ... 2nd camera 18a, 18b ... 3rd camera 25, 26 ... Three-dimensional position calculation part 27 ... Reconstruction calculating part M ... Subject m ... Marker

Claims (3)

電磁波を被検体に照射する照射手段と、前記被検体を透過する電磁波を検出する検出手段と、前記照射手段および前記検出手段を互いに連動して移動させる移動手段と、前記移動手段により移動される前記検出手段から得られた投影像の一群に基づいて再構成演算処理を行い、断層像または／および３次元画像を作成する画像作成手段とを備えた断層撮影装置において、
前記照射手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに所定の位置に配置されるマーカの光学像を撮像する第１光学撮像手段と、
前記検出手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに前記マーカの光学像を撮像する第２光学撮像手段と、
前記第１光学撮像手段及び前記第２光学撮像手段の検知結果に基づいて、前記照射手段及び前記検出手段の３次元位置を算定する算定手段とを備え、
前記算定手段は、前記マーカの３次元位置と、前記第１光学撮像手段から得られた画像と、前記第１光学撮像手段及び前記照射手段の間の相対的な位置関係とに基づいて、前記照射手段の３次元位置を算定し、かつ、前記マーカの３次元位置と、前記第２光学撮像手段から得られた画像と、前記第２光学撮像手段及び前記検出手段の間の相対的な位置関係とに基づいて、前記検出手段の３次元位置を算定し、
前記画像作成手段は、前記算定手段により算定された前記照射手段及び前記検出手段の３次元位置を用いて前記再構成演算処理を行い、
前記装置は、さらに、固定的に設置されて、前記マーカの光学像を撮像する第３光学撮像手段を備え、
前記マーカは前記移動手段に配置され、
前記算定手段は、さらに、前記第３光学撮像手段の３次元位置と、前記第３光学撮像手段から得られた画像とに基づいて、前記マーカの３次元位置を求めることを特徴とする断層撮影装置。 Irradiation means for irradiating the subject with electromagnetic waves, detection means for detecting electromagnetic waves that pass through the subject, movement means for moving the irradiation means and the detection means in conjunction with each other, and movement by the movement means In a tomography apparatus comprising: an image creation means for performing a reconstruction calculation process based on a group of projection images obtained from the detection means and creating a tomogram or / and a three-dimensional image;
Provided at a position where the relative positional relationship with the irradiating means is constant, when obtaining a group of projection images, an optical image of a marker placed at a predetermined position is captured at each time point when each projection image is obtained. First optical imaging means ;
A second optical imaging unit which is provided at a position where the relative positional relationship with the detection unit is constant and obtains a group of projection images, and captures an optical image of the marker at each time point when each projection image is obtained; ,
A calculation unit that calculates a three-dimensional position of the irradiation unit and the detection unit based on detection results of the first optical imaging unit and the second optical imaging unit ;
The calculation means is based on a three-dimensional position of the marker, an image obtained from the first optical imaging means, and a relative positional relationship between the first optical imaging means and the irradiation means. The three-dimensional position of the irradiation means is calculated, and the three-dimensional position of the marker, the image obtained from the second optical imaging means, and the relative position between the second optical imaging means and the detection means Based on the relationship, the three-dimensional position of the detection means is calculated,
Said image forming means, have rows the reconstruction operation process using the three-dimensional position of the irradiating means and the detecting means which is calculated by said calculating means,
The apparatus further includes third optical imaging means that is fixedly installed and captures an optical image of the marker.
The marker is disposed on the moving means;
The calculation means further obtains a three-dimensional position of the marker based on a three-dimensional position of the third optical imaging means and an image obtained from the third optical imaging means. apparatus. 電磁波を被検体に照射する照射手段と、前記被検体を透過する電磁波を検出する検出手段と、前記照射手段および前記検出手段を互いに連動して移動させる移動手段と、前記移動手段により移動される前記検出手段から得られた投影像の一群に基づいて再構成演算処理を行い、断層像または／および３次元画像を作成する画像作成手段とを備えた断層撮影装置において、
前記照射手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに所定の位置に配置されるマーカの光学像を撮像する第１光学撮像手段と、
前記検出手段との相対的な位置関係が一定となる位置に設けられ、投影像の一群を得る際、各投影像が得られる時点ごとに前記マーカの光学像を撮像する第２光学撮像手段と、
前記第１光学撮像手段及び前記第２光学撮像手段の検知結果に基づいて、前記照射手段及び前記検出手段の３次元位置を算定する算定手段とを備え、
前記算定手段は、前記マーカの３次元位置と、前記第１光学撮像手段から得られた画像と、前記第１光学撮像手段及び前記照射手段の間の相対的な位置関係とに基づいて、前記照射手段の３次元位置を算定し、かつ、前記マーカの３次元位置と、前記第２光学撮像手段から得られた画像と、前記第２光学撮像手段及び前記検出手段の間の相対的な位置関係とに基づいて、前記検出手段の３次元位置を算定し、
前記画像作成手段は、前記算定手段により算定された前記照射手段及び前記検出手段の３次元位置を用いて前記再構成演算処理を行い、
前記マーカは３点以上であることを特徴とする断層撮影装置。 Irradiation means for irradiating the subject with electromagnetic waves, detection means for detecting electromagnetic waves that pass through the subject, movement means for moving the irradiation means and the detection means in conjunction with each other, and movement by the movement means In a tomography apparatus comprising: an image creation means for performing a reconstruction calculation process based on a group of projection images obtained from the detection means and creating a tomogram or / and a three-dimensional image;
Provided at a position where the relative positional relationship with the irradiating means is constant, when obtaining a group of projection images, an optical image of a marker placed at a predetermined position is captured at each time point when each projection image is obtained. First optical imaging means ;
A second optical imaging unit which is provided at a position where the relative positional relationship with the detection unit is constant and obtains a group of projection images, and captures an optical image of the marker at each time point when each projection image is obtained; ,
A calculation unit that calculates a three-dimensional position of the irradiation unit and the detection unit based on detection results of the first optical imaging unit and the second optical imaging unit ;
The calculation means is based on a three-dimensional position of the marker, an image obtained from the first optical imaging means, and a relative positional relationship between the first optical imaging means and the irradiation means. The three-dimensional position of the irradiation means is calculated, and the three-dimensional position of the marker, the image obtained from the second optical imaging means, and the relative position between the second optical imaging means and the detection means Based on the relationship, the three-dimensional position of the detection means is calculated,
Said image forming means, have rows the reconstruction operation process using the three-dimensional position of the irradiating means and the detecting means which is calculated by said calculating means,
The tomography apparatus characterized in that the marker has three or more points . 請求項１または請求項２に記載の断層撮影装置において、
前記各光学撮像手段は、それぞれ複数であることを特徴とする断層撮影装置。 The tomography apparatus according to claim 1 or 2 ,
A tomography apparatus characterized in that each of the optical imaging means is plural.
JP2004380609A 2004-12-28 2004-12-28 Tomography equipment Active JP4479503B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004380609A JP4479503B2 (en) 2004-12-28 2004-12-28 Tomography equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004380609A JP4479503B2 (en) 2004-12-28 2004-12-28 Tomography equipment

Publications (2)

Publication Number Publication Date
JP2006181252A JP2006181252A (en) 2006-07-13
JP4479503B2 true JP4479503B2 (en) 2010-06-09

Family

ID=36734760

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004380609A Active JP4479503B2 (en) 2004-12-28 2004-12-28 Tomography equipment

Country Status (1)

Country Link
JP (1) JP4479503B2 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5661624B2 (en) * 2008-08-13 2015-01-28 コーニンクレッカ フィリップス エヌ ヴェ Removal of ring artifacts due to mechanical alignment of 3D rotational X-ray scanner system
KR101787713B1 (en) * 2015-11-24 2017-10-20 메디퓨처(주) Digital breast tomosynthesis for detecting position angle and correcting trace of x-ray focal spot
KR101787714B1 (en) * 2015-11-24 2017-10-20 메디퓨처(주) Digital breast tomosynthesis
US10902594B2 (en) 2017-09-26 2021-01-26 Shimadzu Corporation Medical x-ray image processing apparatus and X-ray imaging apparatus
JP6988732B2 (en) 2018-08-02 2022-01-05 株式会社島津製作所 Radiation image processing equipment and radiation image processing method

Also Published As

Publication number Publication date
JP2006181252A (en) 2006-07-13

Similar Documents

Publication Publication Date Title
JP5501443B2 (en) Radiation image capturing apparatus, radiation image capturing method, body movement amount measuring method, and program
JP4415762B2 (en) Tomography equipment
JP5444718B2 (en) Inspection method, inspection device, and inspection program
JP4537129B2 (en) System for scanning objects in tomosynthesis applications
CN110621985B (en) X-ray computed tomography apparatus
JP5019879B2 (en) X-ray CT apparatus, image processing program, and image processing method
JP4561990B2 (en) X-ray equipment
WO2008019355A2 (en) Ct scanner including a camera to obtain external images of a patient
JP4408664B2 (en) Cone beam X-ray CT apparatus and phantom used therefor
JP5293920B2 (en) X-ray tomography equipment
JP2012112790A (en) X-ray ct apparatus
US8213565B2 (en) Method for correcting truncated projection data
JP4479503B2 (en) Tomography equipment
US20120027170A1 (en) Radiological image capturing and displaying method and apparatus
JP2001013089A (en) X-ray tomographic imaging apparatus
JP2006296926A (en) X-ray imaging apparatus, image processing method, computer readable storage medium and program
JP2008183142A (en) Pet-ct apparatus
JPH04307035A (en) Radiographic apparatus
JP5574002B2 (en) X-ray inspection equipment
JP5676883B2 (en) X-ray CT system
JP2006292462A (en) Computer tomographic photography system
JP4653461B2 (en) Digital X-ray tomography apparatus
JP4609643B2 (en) X-ray CT system
JP2010233762A (en) X-ray tomography apparatus
CN111050647B (en) Radiographic apparatus

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20070302

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20091113

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20091124

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100121

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20100223

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20100308

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130326

Year of fee payment: 3

R151 Written notification of patent or utility model registration

Ref document number: 4479503

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140326

Year of fee payment: 4