JP6257922B2 - Nuclear medicine imaging device and gantry device - Google Patents

Description

  Embodiments described herein relate generally to a nuclear medicine imaging apparatus and a gantry apparatus.

  Conventionally, nuclear medicine imaging apparatuses such as a gamma camera and a single photon emission computed tomography (SPECT) apparatus of a gamma camera type can perform functional diagnosis in a living tissue of a subject. As a device, it is widely used in today's medical field. In a nuclear medicine examination, a gamma camera or a SPECT apparatus photographs an image (SPECT image) in which a distribution of a radiopharmaceutical (tracer) administered to a subject is depicted by, for example, a SPECT imaging method. In a nuclear medicine examination, for example, an index-performed perfusion image that quantitatively represents the dynamics of blood flow passing through capillaries in brain tissue from a SPECT image obtained by photographing the head of a subject in time series. Is generated and displayed.

  Here, in a gamma camera which is a radiation detector, an analog circuit such as an operational amplifier is used as a detector circuit. Since such an analog circuit generates heat when energized, the air around the detector is warmed. For this reason, when the whole gantry device on which the gamma camera is mounted is covered with a cover, heat is trapped inside the gantry device.

  In particular, when the gamma camera is blocked by a dome so that the gamma camera is not exposed to the subject, the temperature of the dome and the internal space of the dome increases. The internal space formed by the dome is an imaging space into which an imaging site of the subject is inserted. Therefore, when the subject is examined, the temperature in the dome increases. For example, even if a fan for blowing air is attached to the cover, the periphery of the dome surrounded by the detector is not efficiently cooled.

  In nuclear medicine examination, in order to improve the image quality of collected images, a detector that generates heat is brought as close as possible to the subject, so that the subject is affected by the heat generated by the detector and feels hot. As a result, the nuclear medicine test may not always be performed in a comfortable environment for the subject. In addition, since the subject autonomously adjusts the body temperature, the heart rate naturally increases and the blood flow velocity increases or the blood flow volume increases during the examination. Such a phenomenon affects the inspection image obtained from the inspection result.

Japanese Patent Application Laid-Open No. 11-212833

  The problem to be solved by the present invention is to provide a nuclear medicine imaging apparatus and a gantry device that can perform an examination in a comfortable environment for a subject.

The nuclear medicine imaging apparatus according to the embodiment includes a detector, a dome, and an outlet. The detector detects radiation emitted from the subject. The dome blocks the detector and forms an imaging space into which the subject is inserted. The outlet is formed in the dome and blows out air blown from the air conditioner. The temperature of the air blown from the air conditioner is lower than the temperature of the air in the imaging space.

FIG. 1 is a diagram for explaining an overall configuration example of a SPECT apparatus according to the present embodiment. FIG. 2 is a diagram for explaining the positional relationship between the dome and the gamma camera shown in FIG. FIG. 3 is a block diagram illustrating a configuration example of the cooling system according to the present embodiment. FIG. 4 is a diagram (1) showing a first example of forming the outlet. FIG. 5 is a diagram (2) showing a first example of forming the outlet. FIG. 6 is a diagram (1) illustrating a second example of forming the outlet. FIG. 7 is a diagram (2) illustrating a second example of forming the outlet.

  Hereinafter, embodiments of a nuclear medicine imaging apparatus will be described in detail with reference to the accompanying drawings. In the following embodiments, a SPECT apparatus that performs gamma camera type single photon emission tomography (SPECT) will be described as an example of a nuclear medicine imaging apparatus. The contents of the embodiments described below can also be applied to nuclear medicine imaging apparatuses such as a gamma camera and a positron emission computed tomography (PET) apparatus.

(Embodiment)
First, an example of the overall configuration of the SPECT apparatus according to this embodiment will be described. FIG. 1 is a diagram for explaining an overall configuration example of a SPECT apparatus according to the present embodiment. FIG. 2 is a diagram for explaining the positional relationship between the dome and the gamma camera shown in FIG. As shown in FIG. 1, the SPECT apparatus according to the present embodiment includes a gantry device 10, a bed device 20, and a console device 30. The SPECT apparatus illustrated in FIG. 1 is a SPECT apparatus for head inspection.

  The gantry device 10 is a device that collects detection data obtained by detecting radiation (gamma rays) emitted from a radiopharmaceutical administered to a subject and selectively taken into a living tissue of the subject. The gantry device 10 is entirely covered with a cover, as illustrated in FIG.

  The gantry device 10 illustrated in FIG. 1 includes three gamma cameras (gamma camera 100, gamma camera 101, and gamma camera 102) as shown in FIG. That is, the SPECT apparatus illustrated in FIG. 1 is a three-detection system SPECT apparatus.

  The gamma camera 100, the gamma camera 101, and the gamma camera 102 are detectors that detect gamma rays emitted from a radiopharmaceutical (tracer) nuclide (RI: Radio Isotope) that is selectively taken into the living tissue of the subject. .

  Specifically, each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 two-dimensionally detects the intensity distribution of gamma rays emitted from the subject. Each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 generates detection data obtained by, for example, amplifying and A / D converting the detected two-dimensional gamma ray intensity distribution data, and the generated detection data will be described later. It transmits to the console apparatus 30.

  For example, each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 is a photon counting radiation detector having a scintillator and a photomultiplier tube (PMT). The scintillator converts gamma rays into light having a peak in the ultraviolet region. The PMT multiplies the light emitted from the scintillator and converts it into an electrical signal. Each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 includes an analog circuit that performs amplification processing of an analog electric signal output from the PMT.

  Each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 is provided with a collimator that limits the incident direction. Each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 detects gamma rays incident in an incident direction limited by, for example, a lead collimator.

  The gantry device 10 illustrated in FIG. 1 has a dome 11. The dome 11 is attached to the front surface of the gantry device 10 as illustrated in FIG. As illustrated in FIG. 2, the dome 11 has a shape in which a substantially flat panel with a circular center is combined with a hollow cylinder. With this panel, the dome 11 is attached to the gantry device 10 from the bed device 20 side. By attaching the dome 11 to the gantry device 10, the gamma camera 100, the gamma camera 101, and the gamma camera 102 surround the dome 11. Further, as the dome 11 is attached to the gantry device 10, the inside of the hollow cylinder becomes an imaging space 12 into which the subject is inserted as illustrated in FIG. That is, the dome 11 forms an imaging space 12 into which the subject is inserted, as illustrated in FIG. In addition, the gamma camera 100, the gamma camera 101, and the gamma camera 102 are arranged outside the dome 11 by mounting the dome 11. As a result, the subject whose head is inserted into the imaging space 12 can undergo a nuclear medicine examination of the head without directly looking at the gamma camera 100, the gamma camera 101, and the gamma camera 102.

  Further, the gantry device 10 has a camera driving unit (not shown). This camera driving unit is a device that moves each of the gamma camera 100, the gamma camera 101, and the gamma camera 102. For example, the camera driving unit moves each gamma camera to a predetermined position along the circumferential direction of the imaging space 12 formed by the dome 11. For example, the camera drive unit moves each gamma camera to a predetermined position along the radial direction of the imaging space 12 formed by the dome 11. In addition, for example, the camera driving unit moves the gamma camera 100, the gamma camera 101, and the gamma camera 102 and arranges them at a predetermined angle (for example, 120 degrees) to maintain an interval between the gamma cameras. In the state, the three gamma cameras are rotationally driven along the circumferential direction of the imaging space 12.

  As a result, each of the gamma camera 100, the gamma camera 101, and the gamma camera 102 rotates around the subject to generate data in a plurality of directions of 360 degrees. The time required for each rotation of the gamma camera 100, the gamma camera 101, and the gamma camera 102 is usually several minutes.

  The couch device 20 is a device having a top plate 21 that is inserted into the imaging space 12 together with a subject. Further, the bed apparatus 20 includes a top plate support portion 22 that supports the top plate 21 so as to be movable into the imaging space 12, and a moving mechanism 23 that supports the top plate support portion 22 so as to be movable in the vertical direction. The movement of the top plate 21 in the longitudinal direction may be performed by the top plate support portion 22 or by the movement mechanism 23.

  The console device 30 is a device that accepts an operation of the SPECT device by an operator and reconstructs a SPECT image of the subject from the detection data collected by the gantry device 10.

  Specifically, the console device 30 controls the gantry device 10 and the couch device 20 to take a SPECT image. More specifically, the console device 30 generates correction data by performing correction processing such as offset correction and sensitivity correction on the detection data collected by the gantry device 10. Then, the console device 30 reconstructs a SPECT image by a predetermined reconstruction process using the projection data. As the predetermined reconstruction process, for example, a reconstruction process by a successive approximation method may be mentioned. In addition, the console device 30 can generate a perfusion image from a SPECT image obtained by imaging the head of the subject in time series, for example. The console device 30 displays a SPECT image and a perfusion image on the monitor.

  The operation of the SPECT apparatus at the time of capturing a SPECT image will be briefly described. First, before photographing, the top support 22 of the bed apparatus 20 is stopped at an initial position lower than the photographing space 12 outside the gantry apparatus 10. When imaging is started, first, a subject to which a tracer is administered is placed on the top 21, and then the top support 22 is placed in the imaging space 12 of the gantry 10 based on an instruction from the operator. It is moved upward to the same height as the center, and then the top 21 is moved into the imaging space 12 together with the subject.

  When the top 21 is moved into the shooting space 12, shooting is performed. Specifically, the gantry device 10 detects gamma rays emitted from the subject while each gamma camera rotates, and transmits detection data to the console device 30. Thereby, the console apparatus 30 reconfigure | reconstructs a SPECT image, or produces | generates a perfusion image from the time series data of a SPECT image.

  When imaging is finished, the top 21 is moved out of the imaging space 12 together with the subject, and then the top support 22 is moved downward to the initial position.

  The overall configuration of the SPECT apparatus according to the present embodiment has been described above. Under such a configuration, the SPECT apparatus according to the present embodiment reconstructs a SPECT image.

  Here, as described above, the gantry device 10 of the SPECT apparatus according to the present embodiment blocks the gamma camera 100, the gamma camera 101, and the gamma camera 102, which are detectors, and forms an imaging space 12 into which the subject is inserted. The dome 11 is provided. On the other hand, the gamma camera 100, the gamma camera 101, and the gamma camera 102 use analog circuits that generate heat when energized. For this reason, heat accumulates inside the gantry device 10 that is entirely covered with a cover. Further, since the dome 11 is surrounded by the gamma camera 100, the gamma camera 101, and the gamma camera 102, the temperature of the dome 11 itself increases, and as a result, the temperature of the imaging space 12 also increases. Here, in the nuclear medicine examination, in order to improve the quality of the SPECT image, a detector that generates heat is brought as close as possible to the subject.

  For this reason, the nuclear medicine examination may not always be an examination performed in a comfortable environment for the subject. Further, at the time of examination, due to heat, the heart rate of the subject increases and the blood flow velocity increases, or the blood flow volume increases. Such a phenomenon affects, for example, a perfusion image.

  Therefore, the gantry device 10 of the SPECT apparatus according to the present embodiment is configured as follows so that the examination can be performed in an environment comfortable for the subject. In the present embodiment, a blowout port that is formed in the dome 11 and blows out air blown from the air conditioner is installed.

  Moreover, in this embodiment, the temperature sensor which measures the temperature of the imaging | photography space 12, and the control part which adjusts the temperature of the air ventilated from an air conditioner based on the temperature which the temperature sensor measured are installed. The “air conditioner, air outlet, temperature sensor, and control unit” serves as a cooling system for cooling the imaging space 12. FIG. 3 is a block diagram illustrating a configuration example of the cooling system according to the present embodiment.

  As shown in FIG. 3, the cooling system according to the present embodiment includes an air conditioner 104, a blower fan 1105, a blower pipe 106, and a blowout port 107. The air conditioner 104 is a device that takes in external air and releases air adjusted to an arbitrary temperature within a possible range. The air conditioner 104 may be set inside the gantry device 10 or may be installed outside the gantry device 10.

  The blower fan 105 is a device that sends out the air whose temperature is adjusted by the air conditioner 104 to the blower pipe 106, and the blower pipe 106 is a hollow pipe for guiding the air blown by the blower fan 105 to the outlet 107. It is.

  Further, the cooling system according to the present embodiment includes a temperature sensor 108 and a control unit 109 as shown in FIG. The temperature sensor 108 detects the temperature of the imaging space 12. The temperature sensor 108 is attached to the photographic space 12 side of the dome 11 so that the temperature of the photographic space 12 can be detected, for example.

  The control unit 109 is a device that controls the operation of the air conditioner 104. For example, the control unit 109 performs ON / OFF control of the power supplied to the air conditioner 104 and adjusts the temperature of air blown from the air conditioner 104. In the present embodiment, the control unit 109 adjusts the temperature of air blown from the air conditioner 104 based on the temperature measured by the temperature sensor 108. The control unit 109 may be set inside the gantry device 10 or may be installed outside the gantry device 10. Alternatively, the control unit 109 may be installed in the console device 30.

  In the present embodiment, the shooting space 12 is cooled by the air blown by the air conditioner 104 by forming the air outlet 107 in the dome 11. Thus, in the present embodiment, even during examination, the temperature of the imaging space 12 is prevented from rising due to heat generated by the gamma camera 100, the gamma camera 101, and the gamma camera 102, and a comfortable environment for a subject that is imaged for a long time. It becomes possible to execute the inspection.

  Here, the outlet 107 can be formed in the dome 11 in various forms. For example, in the first formation example, the air outlet 107 is formed in the dome 11 so that the air blown from the air conditioner 104 is blown out to the imaging space 12. Alternatively, for example, in the second formation example, the air outlet 107 is formed inside the dome 11 so as to blow out the air blown from the air conditioner 104 along the insertion direction of the subject. Hereinafter, an example of the form of the outlet 107 formed in the dome 11 will be described with reference to FIGS. 4 to 7. 4 and 5 are diagrams showing a first example of forming the outlet. 6 and 7 are diagrams showing a second example of forming the outlet.

  4 and 5 are diagrams showing an example of a first formation example in which the air outlet 107 is formed in the dome 11 so that the air blown from the air conditioner 104 is blown out to the imaging space 12. FIG. 4 is a cross-sectional view showing a side surface of the dome 11. As illustrated in FIG. 4, a hollow cylinder 111 that forms a photographing space 12 is attached to the dome 11. As illustrated in FIG. 4, a hollow cylinder 112 shorter than the cylinder 111 is attached to the dome 11 inside the cylinder 111.

  The left view of FIG. 5 is a front view of the cylinder 111 and the cylinder 112 as viewed from the bed apparatus 30, and the right view of FIG. 5 is a perspective view of the cylinder 111 and the cylinder 112 as viewed from the side of the gantry apparatus 10. is there. As shown in the left diagram of FIG. 5, the cylinder 111 and the cylinder 112 are connected at three locations. As illustrated in FIGS. 4 and 5, the air duct 106 is disposed so as to guide the air blown from the air conditioner 104 into a cavity formed between the cylinder 111 and the cylinder 112.

  As illustrated in FIGS. 4 and 5, by arranging a cylinder 112 shorter than the cylinder 111 inside the cylinder 111 forming the imaging space 12, the cooling air blown from the air conditioner 104 to the imaging space 12 is supplied. A blowout port 107 for blowing out is formed. The air outlet 107 is formed along the entire circumference of the imaging space 12 in front of the imaging space 12. The imaging space 12 is adjusted to a temperature comfortable for the subject by the cooling air blown out from the entire periphery.

  Further, as illustrated in FIG. 4, the temperature sensor 108 is installed on the imaging space 12 side of the cylinder 112. Thereby, the temperature sensor 108 detects the temperature of the imaging space 12. When the temperature of the imaging space 12 detected by the temperature sensor 108 is higher than a predetermined threshold, the control unit 109 controls the air conditioner 104 so as to release air having a temperature lower than the current set temperature. Further, when the temperature of the imaging space 12 detected by the temperature sensor 108 becomes lower than a predetermined threshold, the control unit 109 controls the air conditioner 104 so as to release air having a temperature higher than the current set temperature. The predetermined threshold is arbitrarily set by an operator, for example, based on a value that is a comfortable temperature for the subject.

  6 and 7 are diagrams illustrating an example of a second formation example in which the air outlet 107 is formed in the dome 11 so that the air blown from the air conditioner 104 is blown out along the insertion direction of the subject. FIG. 6 is a cross-sectional view showing a side surface of the dome 11. As illustrated in FIG. 6, a hollow cylinder 111 that forms the imaging space 12 is attached to the dome 11. As illustrated in FIG. 6, a hollow cylinder 113 having the same length as the cylinder 111 is attached to the dome 11 inside the cylinder 111.

  The left view of FIG. 7 is a front view of the cylinder 111 and the cylinder 113 as viewed from the bed apparatus 30, and the right view of FIG. 7 is a perspective view of the cylinder 111 and the cylinder 113 as viewed from the side of the gantry apparatus 10. is there. As shown in the left diagram of FIG. 7, the cylinder 111 and the cylinder 113 are connected at three locations. As illustrated in FIGS. 6 and 7, the air duct 106 is disposed so as to guide the air blown from the air conditioner 104 to a space formed between the cylinder 111 and the cylinder 113.

  As illustrated in FIG. 6 and FIG. 7, by arranging a cylinder 113 having the same length as the cylinder 111 inside the cylinder 111 forming the imaging space 12, the insertion direction (of the top plate 21 of the top plate 21 is set inside the dome 11. A ring-shaped cavity in which cooling air flows along the longitudinal direction is formed, and a blow-out port 107 for blowing the cooling air backward is formed.

  The outlet 107 is formed along the entire circumference of the imaging space 12 behind the imaging space 12. The dome 11 is cooled by the cooling air flowing from the front to the rear along the insertion direction in the ring-shaped cavity formed in the dome 11, and the imaging space 12 is cooled by the cooled dome 11. . As a result, the imaging space 12 is adjusted to a temperature comfortable for the subject.

  Further, as illustrated in FIG. 6, the temperature sensor 108 is installed on the imaging space 12 side of the cylinder 113. Thereby, the temperature sensor 108 detects the temperature of the imaging space 12. The control unit 109 adjusts the temperature of the air blown from the air conditioner 104 by comparing the temperature of the imaging space 12 detected by the temperature sensor 108 with a predetermined threshold in the same manner as described above.

  4 to 7 are merely examples. For example, this embodiment may be a case where a plurality of outlets for blowing cooling air toward the imaging space 12 are formed at a plurality of locations on the dome 11. 6 and 7, when a ring-shaped cavity is formed in the dome 11, for example, a plurality of holes are formed in the cylinder 113, and air is blown out from the plurality of holes. Also good.

  Further, the present embodiment may be a case where the temperature sensor 108 is attached to a plurality of locations. In such a case, for example, the control unit 109 adjusts the temperature of the air blown from the air conditioner 104 based on the average temperature at a plurality of locations.

  In the present embodiment, the temperature adjustment control in the imaging space 12 using the temperature sensor 108 and the control unit 109 may not be performed. For example, this embodiment may be a case where the operator or the subject manually adjusts the temperature in the imaging space 12.

  As described above, in the present embodiment, by forming the air outlet for blowing the air blown from the air conditioner 104 in the dome 11, it is possible to prevent the temperature inside the imaging space 12 from rising. As a result, in the present embodiment, the examination can be performed in an environment comfortable for the subject. Further, in the present embodiment, since the temperature inside the imaging space 12 can be prevented, an image is taken while keeping the heart rate and blood flow velocity of the subject at the time of imaging in a resting state. be able to. As a result, in this embodiment, a stable inspection result can be obtained, so that the inspection efficiency can be increased.

  In the present embodiment, by adjusting the temperature using the temperature sensor 108, for example, the imaging space 12 can be prevented from being excessively cooled. As a result, in this embodiment, the examination can be performed in a state where a comfortable environment for the subject is maintained for a long time.

  Depending on the subject, the air blown into the imaging space 12 may feel uncomfortable. For this reason, the present embodiment is a case where a plurality of openable / closable outlets are provided, the outlets at positions where air directly hits the subject are closed, and the outlets at positions where air does not hit the subject directly are opened. There may be. Further, the above opening and closing may be performed by an operator or a subject or may be performed by the control unit 109.

In addition, depending on the subject, the sound generated by the blowing may be uncomfortable. For this reason, in this embodiment, the dome 11 may be provided with a noise canceling function.

  The contents described in the above embodiments can also be applied to a one-detection SPECT apparatus, a two-detection SPECT apparatus, a gamma camera, and a PET apparatus. The contents described in the above embodiment can also be applied to a SPECT-CT apparatus that combines a SPECT apparatus and an X-ray CT apparatus, a PET-CT apparatus that combines a PET apparatus and an X-ray CT apparatus, and the like. .

  Further, in the description of the above-described embodiment, each component of each illustrated device is functionally conceptual and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to the one shown in the figure, and all or a part of the distribution / integration is functionally or physically distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured. Furthermore, all or a part of each processing function performed in each device can be realized by a CPU and a program that is analyzed and executed by the CPU, or can be realized as hardware by wired logic.

  As described above, according to the present embodiment, the examination can be performed in an environment comfortable for the subject.

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

11 Dome 100, 101, 102 Gamma camera 104 Air conditioner 107 Air outlet

Claims (5)

A detector for detecting radiation emitted from the subject;
A dome that blocks the detector and forms an imaging space into which the subject is inserted;
A blowout port that is formed in the dome and blows out air blown from an air conditioner,
With
The temperature of the air blown from the air conditioner is lower than the temperature of the air in the shooting space,
A nuclear medicine imaging apparatus characterized by that. A detector for detecting radiation emitted from the subject;
A dome that blocks the detector and forms an imaging space into which the subject is inserted;
A blowout port that is formed in the dome and blows out air blown from an air conditioner,
With
The dome is disposed inside the first cylinder that forms the imaging space and the first cylinder, and forms a cavity along the insertion direction of the subject with the first cylinder. Having a second cylinder;
The outlet has an air flowing through the said cavity and flows from one end of the cavity in the insertion direction is blown from the air conditioner, it spits it out from the other end of said cavity,
The temperature of the air blown from the air conditioner is lower than the temperature of the air in the shooting space,
A nuclear medicine imaging apparatus. A temperature sensor for measuring the temperature of the imaging space;
Based on the temperature measured by the temperature sensor, a controller that adjusts the temperature of the air blown from the air conditioner;
The nuclear medicine imaging apparatus according to claim 1, further comprising: A detector for detecting radiation emitted from the subject;
A dome that blocks the detector and forms an imaging space into which the subject is inserted;
A blowout port that is formed in the dome and blows out air blown from an air conditioner,
With
The temperature of the air blown from the air conditioner is lower than the temperature of the air in the shooting space,
A gantry device characterized by that. A detector for detecting radiation emitted from the subject;
A dome that blocks the detector and forms an imaging space into which the subject is inserted;
A blowout port that is formed in the dome and blows out air blown from an air conditioner,
With
The dome is disposed inside the first cylinder that forms the imaging space and the first cylinder, and forms a cavity along the insertion direction of the subject with the first cylinder. Having a second cylinder;
The outlet has an air flowing through the said cavity and flows from one end of the cavity in the insertion direction is blown from the air conditioner, it spits it out from the other end of said cavity,
The temperature of the air blown from the air conditioner is lower than the temperature of the air in the shooting space,
A gantry device characterized by that.

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