JP2011053130A - Image diagnostic equipment - Google Patents

Abstract

[PROBLEMS] To prevent deterioration in operability of an imaging operation in a plurality of apparatuses such as a PET apparatus and a CT apparatus, and to inherently overlap due to image quality deterioration due to a position shift of a bed and an imaging time difference between the PET apparatus and the CT apparatus. An image diagnostic apparatus capable of suppressing image shift is provided.
An image diagnostic apparatus 10 includes an X-ray generation source 30 that generates X-rays, and a gamma ray 150 generated when an X-ray 100 from the X-ray generation source 30 is incident on a site in a subject M. The detectors 40 and 41 for detecting both of the X-rays 100 transmitted through the subject M are included, and the plurality of detectors 40 and 41 are arranged in a ring shape to form the fixed ring portion 21. ing.
[Selection] Figure 5

Description

  The present invention relates to an image diagnostic apparatus, and more particularly to an image diagnostic apparatus such as an integrated PET-CT apparatus.

  A PET-CT apparatus has been developed as an apparatus for image diagnosis of a subject (photographer). As shown in FIG. 10, the PET-CT apparatus 200 performs image diagnosis by placing the subject M on the couch top 201 and inserting the subject M into the opening 205. The PET-CT apparatus 200 demonstrates its power as a diagnostic imaging apparatus for tumors, for example, by taking advantage of the modality of the PET (Position Emission Computed Tomography) apparatus 202 and the modality of the CT (computed Tomography) apparatus 203. To do. That is, functional information can be obtained by the PET apparatus 202, and morphological information can be obtained by the CT apparatus 203. By displaying the functional information and the morphological information in an overlapped manner, which part of the body of the subject M can be selected. It is an effective device to give an indication of whether there is such a disease.

  The PET-CT apparatus 200 has a structure in which the frame of the PET apparatus 202 and the frame of the CT apparatus 203 are simply arranged in the body axis direction of the subject M, that is, the frame of the PET detector and the CT apparatus in the frame of the PET apparatus 202. The CT detectors are simply arranged side by side in the body axis direction of the subject, and devices having two different functions are combined. Therefore, the PET-CT apparatus 200 has a hybrid configuration in which the alignment is adjusted so that the coordinate systems of the PET detector in the gantry of the PET apparatus 202 and the CT detector in the gantry of the CT apparatus 203 coincide with each other, The subject M is scanned separately in time by the PET detector and the CT detector, and the reconstructed images are superimposed and displayed by the viewer.

  The PET device detects the gamma rays (γ rays) emitted from the RI by administering, for example, glucose labeled with RI (RadioIsotopic) to the site (tissue) of the subject, and detects the RI-labeled Used to collect and measure biodistribution to detect cancer early, for example. Cancer cells consume a larger amount of glucose than normal cells, and RI label accumulates. By imaging the radiation emitted from the RI label, for example, the presence or absence of cancer in the whole body of subject M, metastasis Can be diagnosed.

  In the CT apparatus, the X-ray tube rotates around the subject M so that the X-rays generated from the X-ray tube pass through the subject M, and the transmitted X-rays are received by the X-ray detector. To obtain a tomographic image of the subject. Inside the subject M, the magnitude of X-ray absorption varies depending on the tissue. The internal structure of the subject M can be obtained by calculating the X-ray absorption distribution inside the subject M from the data acquired by the X-ray detector.

  Patent Document 1 discloses a radiation detector module used in a tomography apparatus, and the radiation detector module is connected to a scintillation layer that converts X-rays into light, and is coupled to the scintillation layer to transmit light. A light detection unit for detection is provided.

JP 2009-25308 A

  By the way, as described above, in the PET-CT apparatus 200 shown in FIGS. 10 and 11, the PET detector in the gantry of the PET apparatus and the CT detector in the gantry of the CT apparatus are simply arranged in the body axis direction of the subject. They are arranged side by side. For this reason, enlargement and complication of the PET-CT apparatus are inevitable, and the apparatus is expensive. Moreover, the functional information by the PET apparatus and the morphological information by the CT apparatus are collected at different positions on the couch top, and then the functional information image data and the morphological information image data are fused and overlapped. It is necessary to work to obtain the combined image data. For this reason, the operability of the PET-CT apparatus is lowered, and there is a possibility that the image quality of the superimposed image data is lowered due to the positional deviation of the couch top.

  The present invention has been made in view of the above, and an object of the present invention is to prevent deterioration in operability of an imaging operation in a plurality of apparatuses such as a PET apparatus and a CT apparatus, to reduce image quality due to a position shift of a bed, and to a PET apparatus. And an image diagnostic apparatus capable of suppressing a shift of an essential superimposed image caused by a time difference of imaging in a plurality of apparatuses such as a CT apparatus and a CT apparatus.

  The invention of claim 1 is an image diagnostic apparatus comprising an X-ray generation source for generating X-rays, wherein the X-ray from the X-ray generation source has passed through a site in a subject. By having a plurality of detectors for detecting both X-rays and gamma rays emitted from a radioisotope (RI) administered to the subject, and arranging the plurality of detectors in a ring shape A fixing ring portion is configured. As a result, it is possible to prevent a reduction in operability of imaging work in a plurality of apparatuses such as a PET apparatus and a CT apparatus, and it is possible to suppress a decrease in image quality due to a bed position shift.

  According to a second aspect of the present invention, in the diagnostic imaging apparatus, the imaging diagnostic apparatus has an opening centered on the system axis of the diagnostic imaging apparatus, and the fixing ring section is arranged centered on the system axis, A plurality of radiation detection modules are configured by laminating a first detector to detect and a second detector to detect the X-ray, and the second detector is compared to the first detector. It is arranged on the system axis side. As a result, gamma rays having a strong transmission power compared to the X-ray transmission power can be detected by the first detector transmitted through the second detector and away from the system axis, compared to the transmission power of the gamma rays. X-rays with weak penetrating power can be detected by the second detector on the system axis side.

  According to a third aspect of the present invention, in the diagnostic imaging apparatus, the first detector receives a first scintillator layer that converts the gamma rays into light, and receives the light obtained from the scintillator layer into an electrical signal. And a second scintillator layer that converts the X-rays into light, and a second light receiver that receives the light obtained by the scintillator layer and converts it into an electrical signal. It is characterized by having. As a result, the first detector can convert the gamma ray into an electric signal and the second detector can convert the X-ray into an electric signal.

  According to a fourth aspect of the present invention, in the diagnostic imaging apparatus, the imaging diagnostic apparatus includes an opening device centered on the system axis of the diagnostic imaging apparatus, and the fixing ring portion is formed centering on the system axis, A radiation detection module is constituted by the common detector that detects both the X-rays. Thereby, since both the gamma rays and the X-rays can be detected by the radiation detection module constituted by a common detector, the structure is simplified and the size can be further reduced.

  According to a fifth aspect of the present invention, in the diagnostic imaging apparatus, the radiation detection module receives a scintillator layer that converts the gamma rays into light and converts the X-rays into light, and the light obtained by the scintillator layers. It has the light receiver changed into an electrical signal, It is characterized by the above-mentioned. As a result, both gamma rays and X-rays can be converted into electrical signals, the structure is simplified, and the size can be further reduced.

The invention of claim 6 is the diagnostic imaging apparatus, wherein the X-ray generation source is an X-ray tube,
The rotating part which is an X-ray generator which has the said X-ray tube and the rotation guide part which rotates the said X-ray tube along the circumference | surroundings of the said fixed ring part is characterized by the above-mentioned. Thereby, the radiation detection module can detect a gamma ray and an X-ray simultaneously by only rotating the X-ray tube around the fixed ring portion by the rotation guide portion.

  According to a seventh aspect of the present invention, in the diagnostic imaging apparatus, the two fixing ring portions are arranged side by side along the system axis, and the rotation guide portions are arranged concentrically on each of the fixing ring portions. It is characterized by being. Thereby, the X-ray generation source can be stably rotated by each rotation guide portion with respect to each fixed ring portion.

  According to the present invention, it is possible to prevent deterioration in operability of an imaging operation in a plurality of apparatuses such as a PET apparatus and a CT apparatus, a reduction in image quality due to a position shift of a bed, and imaging in a plurality of apparatuses such as a PET apparatus and a CT apparatus. It is possible to suppress an essential overlay image shift caused by the time difference.

It is a perspective view which shows the integrated PET-CT apparatus which is embodiment of the image diagnostic apparatus of this invention. FIG. 2 is a diagram showing a rotating part and a fixing ring part arranged in the gantry of the integrated PET-CT apparatus shown in FIG. It is a top view which shows a bed and a fixing ring part. 4A is a front view of the rotating portion and the fixed ring portion, and FIG. 4B is a side view showing the rotating portion and the fixed ring portion. FIG. 5A is a diagram illustrating a structure example of the radiation detection module of the fixing ring portion illustrated in FIG. 4, and FIG. 5B is a diagram illustrating an incidence example of X-rays and gamma rays in the radiation detection module. . 6A is a front view of the rotating portion and the fixed ring portion, and FIG. 6B is a side view showing the rotating portion and the fixed ring portion. FIG. 7A is a diagram illustrating a structure example of the radiation detection module of the fixing ring portion illustrated in FIG. 6, and FIG. 7B is a diagram illustrating an incident example of X-rays and gamma rays in the radiation detection module. . It is a figure which shows another embodiment of this invention. It is a figure which shows another embodiment of this invention. It is a perspective view which shows the conventional PET-CT apparatus. It is a top view of the conventional PET-CT apparatus.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an integrated PET-CT apparatus which is a preferred embodiment of the diagnostic imaging apparatus of the present invention. FIG. 2 is a diagram showing a rotating part and a fixed part arranged in the gantry of the integrated PET-CT apparatus shown in FIG. The image diagnostic apparatus can also be called a medical image apparatus.

  Here, PET is positron emission computed tomography. PET, for example, administers glucose labeled with RI to a subject, detects gamma rays (γ rays) emitted from RI, and detects the RI label. It is used to collect and measure the distribution in the body to detect cancer, etc. at an early stage. In the CT apparatus, the X-ray tube rotates around the subject, so that the X-ray generated from the X-ray tube passes through the subject, and the transmitted X-ray is received by the detector. Obtain a tomographic image of the specimen. Inside the subject, the magnitude of X-ray absorption varies depending on the tissue. By calculating the X-ray absorption distribution inside the subject from the data obtained by the X-ray detector, the structure inside the subject can be obtained.

  An integrated PET-CT apparatus 10 illustrated in FIG. 1 includes a gantry (also referred to as a gantry) 11 and a bed 12. The case 11 of the gantry 11 has a rotating part 20 and a fixed ring part 21, and the rotating part 20 and the fixed ring part 21 are arranged around the system axis CL.

  A bed 12 shown in FIG. 1 includes a top 15 and a pedestal 14, and the subject M to be imaged is laid on the top 15. The top plate 15 of the bed 12 can be moved and positioned by the pedestal portion 14 in the T direction and the Z direction. When imaging the subject M, the subject 15 placed on the top 15 can be inserted into the opening 16 of the gantry 11 and positioned by horizontally moving the top 15 in the T direction. The system axis line CL coincides with the central axis of the opening 16 and is parallel to the body axis direction of the subject M placed on the top 15.

  FIG. 2 shows a configuration example in the gantry 11 of the integrated PET-CT apparatus 10, and the rotating part 20 and the fixing ring part 21 are arranged concentrically around the system axis CL. The rotating part 20 is disposed outside the fixed ring part 21.

  The rotating unit 20 illustrated in FIG. 2 includes an X-ray tube 30 that is an X-ray generation source and a rotation guide unit 31. The rotation guide portion 31 of the rotation portion 20 is disposed concentrically with the fixed ring portion 21 around the system axis CL on the outer side of the fixed ring portion 21. The X-ray tube 30 generates X-rays by supplying a high voltage from the high voltage generator 32. For example, a circular linear motor can be used as the rotation guide unit 31. In FIG. 2, the X-ray tube 30 is counterclockwise about the system axis CL along the R direction by the rotation guide unit 31. Can rotate.

  A fixing ring portion 21 shown in FIG. 2 holds the rotation guide portion 31 described above and is fixed in the case 13. The fixing ring portion 21 is fixed concentrically with respect to the rotation guide portion 31 around the system axis CL. The fixing ring unit 21 includes a PET detector 40 and a CT detector 41. In the example of FIG. 2, the PET detector 40 and the CT detector 41 are integrally provided so as to be stacked in the radial direction with the system axis CL as the center. In FIG. 2, the PET detector 40 and the CT detector 41 are conceptually illustrated.

  FIG. 3 is a plan view showing the bed 12 and the fixing ring portion 21. The subject M placed on the top plate 15 of the bed 12 can be inserted into the opening 16 of the fixing ring portion 21 along the T direction.

  4 shows a specific example of the rotating part 20 and the fixed ring part 21, FIG. 4A is a front view of the rotating part 20 and the fixed ring part 21, and FIG. FIG. 3 is a side view showing a rotating part 20 and a fixing ring part 21.

  As shown in FIG. 4, the rotating part 20 and the fixed ring part 21 are arranged concentrically around the system axis CL. However, as shown in FIG. 4 (B), the rotating part 20 and the fixing ring part 21 are arranged apart from each other by a distance W along the system axis CL. As already described, the X-ray tube 30 can be rotated counterclockwise around the system axis CL along the R direction by the rotation guide 31. As a result, the X-ray tube 30 is rotated in the counterclockwise direction around the system axis CL along the R direction by the rotation guide 31 in the counterclockwise direction, as shown by the arrow. The X-rays 100 can be emitted to the fixed ring portion 21 in a so-called oblique insertion method along an oblique direction with respect to CL.

  As shown in FIG. 4, the fixing ring portion 21 has a plurality of radiation detection modules 50, and the plurality of radiation detection modules 50 are arranged in a circle around the system axis CL. As shown in FIG. 5, each radiation detection module 50 includes a PET detector 40 and a CT detector 41.

  FIG. 5A shows a structural example of the radiation detection module 50 shown in FIG. FIG. 5B is a diagram illustrating an incidence example of the X-ray 100 and the gamma ray 150 in the radiation detection module 50.

  The radiation detection module 50 illustrated in FIG. 5 is a double-sided structure type module, and includes a PET detector 40, a CT detector 41, and a holding unit 55. The holding unit 55 integrally holds the PET detector 40 and the CT detector 41 in a stacked state. The CT detector 41 is disposed closer to the system axis line CL than the PET detector 40. That is, the CT detector 41 is disposed radially inward with the system axis CL as the center, and the PET detector 40 is disposed radially outward. The PET detector 40 is also called a first detector, and the CT detector 41 is also called a second detector. As a result, gamma rays having a strong transmission power compared to the X-ray transmission power are transmitted through the CT detector 41 as the second detector and are detected by the PET detector 40 as the first detector away from the system axis CL. X-rays that can be detected and have a weaker transmission power than the transmission power of gamma rays can be detected by the CT detector 41 on the system axis CL side.

  As shown in FIG. 5, the PET detector 40 includes a first light receiving unit 61 and a first scintillator layer 62. The CT detector 41 includes a second light receiving unit 71 and a second scintillator layer 72.

  For the first scintillator layer 62 and the second scintillator layer 72, for example, LuAG (lutetium garnet) effective for converting X-rays and gamma rays into visible light can be employed. However, the thickness S 1 of the first scintillator layer 62 is set to be larger than the thickness S 2 of the second scintillator layer 72. This is because the transmission power of the gamma ray 150 is stronger than the transmission power of the X-ray 100, and therefore the thickness S 1 of the first scintillator layer 62 is the thickness of the second scintillator layer 72 in order to capture the gamma rays 150 efficiently in the scintillator layer. Further, the first scintillator layer 62 is disposed on the lower surface (outer peripheral side) than the second scintillator layer 72, as compared with S2.

  For example, SiPM (silicon photomultiplier: solid photomultiplier) can be preferably used for the first light receiving unit 61 and the second light receiving unit 71. This SiPM is a light receiving element that enables, for example, 100,000-fold electron amplification by arranging a large number of avalanche photodiodes (APDs) that are semiconductor light receiving elements and using them in Geiger mode.

  The first scintillator layer 62 converts the incident gamma ray 150 into light L1, and the light L1 is received by the first light receiving unit 61, thereby performing optical-electrical signal conversion. The function information data of the PET apparatus subjected to the optical-electrical signal conversion is digitally converted and sent to the information data processing unit 181 of the console 180.

  The second scintillator layer 72 converts the incident X-rays 100 into light L2, and the light L2 is received by the second light receiving unit 71, thereby performing optical-electrical signal conversion. The form information data of the CT apparatus that has been subjected to the optical-electrical signal conversion is digitally converted and sent to the information data processing unit 181 of the console 180.

  Next, an operation example of the above-described PET-CT apparatus 10 will be described.

  As shown in FIGS. 1 and 3, when imaging the subject M, the top 15 moves horizontally in the T direction so that the subject M placed on the top 15 is within the opening 16 of the gantry 11. Insert into.

  As shown in FIG. 2, the X-ray tube 30 generates X-rays by supplying a high voltage from a high voltage generation unit 32, and the X-ray tube 30 is moved along the R direction by the rotation guide unit 31. And rotated counterclockwise about the system axis CL. As shown in FIG. 4B, when the X-ray 100 is exposed from the X-ray tube 30 to the subject M, the X-ray 100 from the X-ray tube 30 is transmitted through the subject M. Then, the light is incident on the second scintillator layer 72 of the CT detector 41 as shown in FIG. The second scintillator layer 72 converts the incident X-ray 100 into light L2, and the light L2 is received by the second light receiving unit 71. Thereby, the light L2 performs optical-electrical signal conversion. The form information data of the CT apparatus that has been subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of a console 180 (not shown).

  In addition, as shown in FIG. 4B, the X-ray 100 from the X-ray tube 30 is exposed to the subject M, and the X-ray 100 is used as a drug in the subject M (for example, a radioisotope: (RI), a gamma ray 150 is generated from the drug administration site D, and the gamma ray 150 is more transmissive than the X-ray 100. Therefore, the second scintillator layer 72 and the second light receiving portion 71 are irradiated. And passes through the first light receiving portion 61 and reaches the first scintillator layer 62. The first scintillator layer 62 converts the incident gamma ray 150 into light L1, and the light L1 is received by the first light receiving unit 61, thereby performing optical-electrical signal conversion.

  The function information data of the PET apparatus subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of the console 180 (not shown). The information data processing unit 181 of the console 180 can obtain functional information data from the PET apparatus and obtain form information data from the CT apparatus. By displaying these function information data and form information data in an overlapping manner, For example, it is possible to give an observation as to what part of the body of the subject M has what disease.

  Thus, the radiation detection module 50 of the fixed ring unit 21 can detect gamma rays and X-rays at the same time only by rotating the X-ray tube 30 around the fixed ring unit 21 by the rotation guide unit 31, and the PET-CT apparatus. No. 10 prevents the operability of the image information collecting work in the PET apparatus and the photographing work in the CT apparatus from being lowered. It is possible to suppress the deviation of the superimposed image that occurs.

  Next, another embodiment of the diagnostic imaging apparatus of the present invention will be described.

  6 and 7 show another embodiment of the diagnostic imaging apparatus of the present invention.

  FIG. 6A is a front view of the rotating portion and the fixed ring portion, and FIG. 6B is a side view showing the rotating portion and the fixed ring portion. FIG. 7 is a view showing a structural example of the radiation detection module of the fixing ring portion shown in FIG.

  In the diagnostic imaging apparatus according to the embodiment of the present invention shown in FIG. 6, the structure of the rotating part 20A and the fixed ring part 21A is different from the structure of the rotating part 20 and the fixed ring part 21 shown in FIG. The structure is the same as that shown in FIGS.

  As illustrated in FIG. 6, the rotating unit 20A includes an X-ray tube 30A and two ring-shaped rotation guide units 31A and 31A. The rotating part 20A is arranged concentrically around the system axis CL on the outer side of the fixed ring part 21A. The X-ray tube 30 </ b> A generates X-rays by supplying a high voltage from the high voltage generator 32. Two fixing ring portions 21A and 21A are arranged side by side with a distance H around the system axis CL. Each rotation guide portion 31A, 31A is fixed to the outer peripheral portion of the corresponding fixing ring portion 21A with the system axis line CL as the center.

  For example, a circular linear motor can be used for each of the rotation guide portions 31A and 31A. In FIG. 6A, the X-ray tube 30 is moved in the R direction by two ring-shaped rotation guide portions 31A and 31A. And can be rotated counterclockwise about the system axis CL.

  The outer periphery of the fixed ring portion 21A shown in FIG. 6 fixes the rotation guide portions 31A and 31A described above, and the fixed ring portion 21A is fixed in the case of the gantry. The fixing ring portion 21A is fixed concentrically with respect to the rotation guide portions 31A and 31A around the system axis CL.

  As shown in FIG. 6, the rotating part 20A and the fixing ring part 21A are arranged concentrically around the system axis CL. As described above, the X-ray tube 30A can be rotated counterclockwise around the system axis CL along the R direction by the two ring-shaped rotation guide portions 31A and 31A. Thereby, the X-ray tube 30A is indicated by an arrow while being rotated counterclockwise around the system axis CL along the R direction by the two rotation guide portions 31A and 31A in the outline of the fixing ring portion 21A. As described above, the X-ray 100 can be emitted to the fixed ring portion 21 along the oblique direction with respect to the system axis CL by a so-called inter-detector slit incidence method.

  As shown in FIG. 6B, each fixing ring portion 21A has a plurality of radiation detection modules 50A, and the plurality of radiation detection modules 50A are arranged in a circle around the system axis CL. Yes. As shown in FIG. 7, each radiation detection module 50A has a PET detector 40 and a CT detector 41, and has the same structure as that of the radiation detection module 50 shown in FIG. is there.

  The X-ray tube 30A is rotated counterclockwise around the system axis CL along the R direction by the rotation guide portions 31A and 31A. Thereby, X-ray tube 30A can be stably rotated with respect to each fixed ring part by two rotation guide parts 31A and 31A. As shown in FIG. 6B, when the X-ray tube 30A exposes the X-ray 100 to the subject M, the X-ray 100 from the X-ray tube 30A is transmitted through the subject M. 7 is incident on the second scintillator layer 72 of the CT detector 41 as shown in FIG. The second scintillator layer 72 converts the incident X-ray 100 into light L2, and the light L2 is received by the second light receiving unit 71. Thereby, the light L2 performs optical-electrical signal conversion. The form information data of the CT apparatus that has been subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of a console 180 (not shown).

  Moreover, as shown in FIG. 6B, when the X-ray tube 30A exposes the X-ray 100 to the subject M, the X-ray 100 from the X-ray tube 30A is within the subject M. When incident on the medicine, gamma rays 150 are generated from the site D of the medicine administration, and the gamma rays 150 are higher in transmittance than the X-ray 100, so that the second scintillator layer 72, the second light receiving portion 71, The light passes through the first light receiving portion 61 and reaches the first scintillator layer 62. The first scintillator layer 62 converts the incident gamma ray 150 into light L1, and the light L1 is received by the first light receiving unit 61, thereby performing optical-electrical signal conversion. The function information data of the PET apparatus subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of the console 180 (not shown). The information data processing unit 181 of the console 180 can obtain functional information data from the PET apparatus and obtain form information data from the CT apparatus. By displaying these function information data and form information data in an overlapping manner, For example, it is possible to give an observation as to what part of the body of the subject M has what disease.

  Thereby, the radiation detection module 50A of the fixed ring portion 21 can simultaneously detect gamma rays and X-rays only by rotating the X-ray tube 30A around the fixed ring portion 21 by the rotation guide portions 31A and 30A. The PET-CT apparatus shown in FIG. 6 and FIG. 7 can prevent the operability of the collection work in the PET apparatus and the imaging work in the CT apparatus from being lowered, and can suppress the deterioration in image quality due to the misalignment of the bed. .

  Next, still another embodiment of the diagnostic imaging apparatus of the present invention will be described.

  8 and 9 show still another embodiment of the present invention.

  The already described radiation detection module 50 shown in FIG. 4 and the radiation detection module 50A shown in FIG. 7 are double-sided detectors composed of two scintillator layers and a light receiving unit. They are next to each other.

  On the other hand, the radiation detection module 50B shown in FIG. 8 and the radiation detection module 50C shown in FIG. 9 are single-sided detectors composed of a pair of scintillator layers and a light receiving section. For this reason, the radiation detection module 50B shown in FIG. 8 and the radiation detection module 50C shown in FIG. 9 are different in the laminated structure between the radiation detection module 50 shown in FIG. 4 and the radiation detection module 50A shown in FIG. Therefore, the structure is simple, the thickness is reduced, and the cost can be reduced. The radiation detection module 50B shown in FIG. 8 and the radiation detection module 50C shown in FIG. 9 can be applied to the fixing ring portions 21 and 21A of the embodiments shown in FIG. 4 and FIG.

  FIG. 8A shows a structural example of the radiation detection module 50B. FIG. 8B is a diagram illustrating an incidence example of the X-ray 100 and the gamma ray 150 in the radiation detection module 50B.

  A radiation detection module 50B shown in FIG. 8 is a single-sided structure type module, and shares a PET detector and a CT detector, and includes a light receiving unit 81, a scintillator layer 82, and a holding unit 85. . The holding unit 55 integrally holds the light receiving unit 81 and the scintillator layer 82 in a stacked state. The scintillator layer 82 is disposed on the system axis side, that is, on the inner side as compared with the light receiving portion 81.

  For the scintillator layer 82, for example, LuAG (lutetium garnet) effective for converting X-rays and gamma rays into visible light can be employed. For example, SiPM (silicon photomultiplier: solid-state photomultiplier) can be preferably used as the light receiving unit 81. Since the scintillator layer 82 detects both X-rays and gamma rays simultaneously, the thickness S3 of the scintillator layer 82 is preferably 5 mm or more.

  As shown in FIG. 8B, the X-ray 100 passes through the subject and enters the scintillator layer 82. The scintillator layer 82 converts the incident X-ray 100 into light L 2, and the light L 2 is received by the light receiving unit 81. Thereby, the light L2 performs optical-electrical signal conversion. The form information data of the CT apparatus that has been subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of a console 180 (not shown).

  Further, when the X-ray 100 is incident on the medicine in the subject, gamma rays 150 are generated from the site of the medicine administration, and the gamma rays 150 reach the scintillator layer 82. The scintillator layer 82 converts the incident gamma ray 150 into light L1, and the light L1 is received by the light receiving unit 81, thereby performing optical-electrical signal conversion. The function information data of the PET apparatus subjected to the optical-electrical signal conversion is digitally converted and sent to an information data processing unit 181 of the console 180 (not shown).

  In the scintillator layer 82, X-rays and gamma rays are differentiated by performing energy discrimination, and are used as form information data of the CT apparatus and function information data of the PET apparatus, respectively.

  Next, FIG. 9A shows a structural example of the radiation detection module 50B. FIG. 9B is a diagram illustrating an incidence example of the X-ray 100 and the gamma ray 150 in the radiation detection module 50B.

  The radiation detection module 50B shown in FIG. 9 is a single-sided structure type module, and shares a PET detector and a CT detector, and includes a light receiving unit 91, a scintillator layer 92, and a holding unit 95. . The holding unit 55 integrally holds the light receiving unit 91 and the scintillator layer 92 in a stacked state. The light receiving portion 91 is disposed on the system axis side, that is, inside the scintillator layer 92.

  The scintillator layer 92 can employ, for example, LuAG (lutetium garnet) effective for converting X-rays and gamma rays into visible light. For example, SiPM (silicon photomultiplier: solid-state photomultiplier) can be preferably used as the light receiving unit 91. Since the scintillator layer 92 detects both X-rays and gamma rays simultaneously, the thickness S3 of the scintillator layer 92 is preferably 5 mm or more.

  As shown in FIG. 9B, the X-ray 100 passes through the subject, passes through the light receiving unit 91, and enters the scintillator layer 92. The scintillator layer 92 converts the incident X-ray 100 into light L2, and the light L2 is received by the light receiving unit 91. Thereby, the light L2 performs optical-electrical signal conversion. The form information data of the CT apparatus subjected to the optical-electrical signal conversion is digitally converted and sent to the information data processing unit 191 of the console 190 (not shown).

  In the scintillator layer 92, X-rays and gamma rays are distinguished by performing energy discrimination, and are used as form information data of the CT apparatus and function information data of the PET apparatus, respectively.

  The diagnostic imaging apparatus of the present invention is an diagnostic imaging apparatus including an X-ray generation source that generates X-rays, wherein the X-ray from the X-ray generation source has transmitted through a site in a subject, It has a plurality of detectors for detecting both gamma rays emitted from the RI (radioisotope) administered to the subject, and the fixed ring portion is arranged by arranging the plurality of detectors in a ring shape. It is configured. As a result, it is possible to prevent a reduction in operability of imaging work in a plurality of apparatuses such as a PET apparatus and a CT apparatus, and it is possible to suppress a decrease in image quality due to a bed position shift.

  In the diagnostic imaging apparatus of the present invention, the imaging diagnostic apparatus has an opening centered on the system axis of the diagnostic imaging apparatus, and the fixing ring section is arranged centering on the system axis, and detects the gamma rays. A plurality of radiation detection modules are configured by stacking a detector and a second detector for detecting the X-ray, and the second detector is on the system axis side as compared to the first detector. Is arranged. As a result, gamma rays having a strong transmission power compared to the X-ray transmission power can be detected by the first detector transmitted through the second detector and away from the system axis, compared to the transmission power of the gamma rays. X-rays with weak penetrating power can be detected by the second detector on the system axis side.

  In the diagnostic imaging apparatus of the present invention, the first detector includes a first scintillator layer that converts the gamma rays into light, and a first light receiver that receives the light obtained from the scintillator layer and converts it into an electrical signal. And the second detector has a second scintillator layer that converts the X-rays into light, and a second light receiver that receives the light obtained by the scintillator layer and converts it into an electrical signal. It is characterized by. As a result, the first detector can convert the gamma ray into an electric signal and the second detector can convert the X-ray into an electric signal.

  In the diagnostic imaging apparatus according to the present invention, the diagnostic imaging apparatus includes an opening device with the system axis of the diagnostic imaging apparatus as a center, and the fixing ring portion is formed with the system axis as the center, and the gamma rays and the X-rays A radiation detection module is constituted by the common detector that detects both. Thereby, since both the gamma rays and the X-rays can be detected by the radiation detection module constituted by a common detector, the structure is simplified and the size can be further reduced.

  In the diagnostic imaging apparatus according to the present invention, the radiation detection module converts the gamma ray into light and converts the X-ray into light, and receives the light obtained from the scintillator layer and converts it into an electrical signal. It has the light receiver which carries out. As a result, both gamma rays and X-rays can be converted into electrical signals, the structure is simplified, and the size can be further reduced.

  In the diagnostic imaging apparatus according to the present invention, the X-ray generation source is an X-ray tube, and the X-ray tube and a rotation guide unit that rotates the X-ray tube along the periphery of the fixed ring unit. A rotating unit that is an X-ray generator. Thereby, the radiation detection module can detect a gamma ray and an X-ray simultaneously by only rotating the X-ray tube around the fixed ring portion by the rotation guide portion.

  In the diagnostic imaging apparatus of the present invention, the two fixing ring portions are arranged side by side along the system axis, and the rotation guide portions are arranged concentrically on each fixing ring portion. Thereby, the X-ray generation source can be stably rotated by the rotation guide portions with respect to the fixed ring portions.

  In the embodiment of the diagnostic imaging apparatus of the present invention, since the PET detector and the CT detector (CT scanner) are integrated in the radial direction in the gantry, the installation space for the gantry of the diagnostic imaging apparatus can be minimized. , Manufacturing cost is low. Since the imaging by the PET detector and the imaging by the CT detector can be performed simultaneously in time, the total imaging time can be shortened, and the subject does not move during the imaging, and the imaging by the PET detector and the CT detection are performed. The superimposition accuracy (superposition time) of imaging by the instrument is improved.

  Since the feeding amount of the top plate for feeding the subject is the same for the PET detector and the CT detector, the sagging in the imaging by the PET detector and the sagging in the imaging by the CT detector are the same, and the overlay accuracy is high. improves. It is not necessary to adjust the alignment between the PET detector and the CT detector. Since the imaging by the PET detector and the imaging by the CT detector are performed simultaneously, a fusion image that is not affected by body movement or respiratory movement during examination of the subject or movement of an invisible organ from the outside can be obtained. Since PET information collection can be started simultaneously with CT imaging, it is possible to greatly improve operability and throughput.

  The present invention is not limited to the above embodiment.

  As an image diagnostic apparatus of the present invention, for example, a PET-CT apparatus can be combined with SPECT (spect: single photon emission computer tomography), MRI, or both. The radiation detection module in each embodiment described above can also use a photon counting system. This photon counting system is a method for detecting the energy of incident photons each time one X-ray or gamma ray photon is incident.

  Furthermore, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments of the present invention. For example, you may delete some components from all the components shown by embodiment of this invention. Furthermore, you may combine the component covering different embodiment suitably.

10 Integrated PET-CT system (image diagnostic system)
11 Mount (also called gantry)
12 Bed 15 Top plate 16 Opening portion 20 Rotating portion 21 Fixing ring portion (also referred to as fixing portion)
30 X-ray tube (X-ray source)
31 Rotation guide part 40 PET detector (first detector)
41 CT detector (second detector)
DESCRIPTION OF SYMBOLS 50 Radiation detection module 55 Holding | maintenance part 61 1st light-receiving part 62 1st scintillator layer 71 2nd light-receiving part 72 2nd scintillator layer 100 X-ray 150 Gamma ray CL System axis line L1, L2 Light

Claims (7)

  An image diagnostic apparatus including an X-ray generation source that generates X-rays, wherein the X-ray from the X-ray generation source has transmitted through a site in a subject, and an RI administered to the subject It has a plurality of detectors for detecting both gamma rays emitted from (radioisotopes), and a fixed ring portion is configured by arranging a plurality of the detectors in a ring shape Diagnostic imaging device. Having an opening around the system axis of the diagnostic imaging apparatus;
The fixing ring portion is disposed around the system axis,
A plurality of radiation detection modules are configured by laminating a first detector that detects the gamma rays and a second detector that detects the X-rays,
The diagnostic imaging apparatus according to claim 1, wherein the second detector is disposed closer to the system axis line than the first detector.   The first detector includes a first scintillator layer that converts the gamma rays into light, and a first light receiver that receives the light obtained from the scintillator layer and converts the light into an electrical signal, and the second detector. The apparatus according to claim 2, further comprising: a second scintillator layer that converts the X-rays into light; and a second light receiver that receives the light obtained from the scintillator layer and converts the light into an electric signal. The diagnostic imaging apparatus described. Having an opening device around the system axis of the diagnostic imaging apparatus;
The fixing ring portion is formed around the system axis,
The diagnostic imaging apparatus according to claim 1, wherein a radiation detection module is configured by the common detector that detects both the gamma rays and the X-rays.   The radiation detection module includes a scintillator layer that converts the gamma rays into light and converts the X-rays into light, and a light receiver that receives the light obtained by the scintillator layer and converts the light into an electrical signal. The diagnostic imaging apparatus according to claim 4. The X-ray generation source is an X-ray tube;
The rotation part which is an X-ray generator which has the said X-ray tube and the rotation guide part which rotates the said X-ray tube along the circumference | surroundings of the said fixed ring part is provided. Item 6. The diagnostic imaging apparatus according to any one of items 5.   The two fixing ring portions are arranged side by side along the system axis at an interval, and the rotation guide portions are arranged concentrically on each of the fixing ring portions. The diagnostic imaging apparatus described.

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