JP7073091B2 - X-ray computer tomography equipment and gantry equipment - Google Patents

Description

Embodiments of the present invention relate to an X-ray computer tomography apparatus and a gantry apparatus.

The gantry device of the X-ray computer tomography device has a built-in floodlight for patient alignment. Visible light emitted from the floodlight passes through the transmissive membrane provided in the housing of the gantry device and irradiates the patient and the bed. Since the permeable membrane is generally transparent or translucent, there is a risk that the patient lying on the bed will see the inside of the gantry housing. If the inside of the gantry housing is visible during the X-ray CT scan, the patient will visually follow the rotating portion that rotates at high speed in the gantry housing. As a result, the head moves, and body movement artifacts occur due to the body movement of the head.

Japanese Unexamined Patent Publication No. 2011-254888 Special Table 2010-500118 Gazette

The problem to be solved by the invention is to reduce the visibility into the gantry housing while maintaining the visibility of the visible light emitted from the floodlight.

The X-ray computer tomography apparatus according to the embodiment is an X-ray computer tomography apparatus including a gantry device for performing X-ray CT imaging and a processing device for controlling the gantry device. Of the gantry housing having an opening into which the subject is inserted and equipped with an imaging mechanism for X-ray CT imaging, at least one floodlight provided in the gantry housing and emitting visible light, and the gantry housing. It has a transmissive film attached to an inner wall portion facing the opening and transmitting visible light emitted from the floodlight, and the transmissive film transmits the visible light and penetrates the inside of the gantry housing. It has a wavelength band that is difficult to see from the outside and belongs to a wavelength band excluding the wavelength to which the color of the visible light belongs.

FIG. 1 is a diagram showing a configuration of an X-ray computer tomography apparatus according to the present embodiment. FIG. 2 is a diagram showing the appearance of the gantry according to the present embodiment. FIG. 3 is a diagram showing a cut surface including the Z axis of the gantry shown in FIG. FIG. 4 is a diagram showing the wavelength distribution of the weight coefficient of the color transmittance that the transmission films of FIGS. 2 and 3 can have. FIG. 5 is a diagram showing a wavelength distribution (transmission spectrum) of the transmittance for each color that the transmission films of FIGS. 2 and 3 can have. FIG. 6 is a diagram showing a cut surface including the Z axis of the gantry according to the application example of the present embodiment.

Hereinafter, the X-ray computer tomography apparatus and the gantry apparatus according to the present embodiment will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration of an X-ray computer tomography apparatus according to the present embodiment. As shown in FIG. 1, the X-ray computer tomography apparatus according to the present embodiment has a gantry 10 and a console 100. For example, the gantry 10 is installed in the CT examination room, and the console 100 is installed in the control room adjacent to the CT examination room. The gantry 10 and the console 100 are connected to each other so as to be able to communicate with each other. The gantry 10 is equipped with an imaging mechanism for CT imaging of the subject P with X-rays. The console 100 is a computer that controls the gantry 10.

As shown in FIG. 1, the gantry 10 has a substantially cylindrical rotating frame 11 in which an opening is formed. The rotating frame 11 is also called a rotating portion. As shown in FIG. 1, an X-ray tube 13 and an X-ray detector 15 arranged so as to face each other with an opening interposed therebetween are attached to the rotating frame 11. The rotating frame 11 is a metal frame formed in an annular shape by a metal such as aluminum. As will be described later, the gantry 10 has a main frame made of a metal such as aluminum. Mainframes are also called fixed parts. The rotating frame 11 is rotatably supported by the main frame.

The X-ray tube 13 generates X-rays. The X-ray tube 13 has a cathode that generates thermions, an anode that receives thermions flying from the cathode and generates X-rays, and a vacuum tube that holds the cathode and the anode. The X-ray tube 13 is connected to the high voltage generator 17 via a high voltage cable. The high voltage generator 17 is attached to, for example, a rotating frame 11. The high voltage generator 17 generates a high voltage applied to the X-ray tube 13 according to the control by the gantry control circuit 29, and supplies the filament heating current. A high voltage is applied between the anode and the cathode housed in the X-ray tube 13. The filament heating current is supplied to the cathode of the X-ray tube 13. The high voltage applied between the anode and cathode of the X-ray tube 13 is called the tube voltage. Further, the flow of thermions generated from the cathode heated by the filament heating current under the high voltage and flying to the anode is called a tube current. The high voltage generator 17 adjusts the tube voltage to the X-ray tube 13 and the tube current according to the X-ray conditions.

The rotary frame 11 receives power from the rotary drive device 21 and rotates around the central axis Z at a constant angular velocity. Any motor such as a direct drive motor or a servo motor is used as the rotation drive device 21. The rotation drive device 21 is housed in, for example, a gantry 10. The rotation drive device 21 receives a drive signal from the gantry control circuit 29 and generates power for rotating the rotation frame 11.

A FOV is set in the opening of the rotating frame 11. A top plate supported by the bed 23 is inserted into the opening of the rotating frame 11. The subject P is placed on the top plate. The sleeper 23 movably supports the top plate. The sleeper driving device 25 is housed in the sleeper 23. The sleeper drive device 25 receives a drive signal from the gantry control circuit 29 and generates power for moving the top plate back and forth, up and down, and left and right. The sleeper 23 positions the top plate so that the imaging portion of the subject P is included in the FOV.

The X-ray detector 15 detects the X-rays generated from the X-ray tube 13. Specifically, the X-ray detector 15 has a plurality of detection elements arranged on a two-dimensional curved surface. Each detection element has a scintillator and a photoelectric conversion element. The scintillator is formed by a substance that converts X-rays into light. The scintillator converts the incident X-rays into a number of photons according to the intensity of the incident X-rays. The photoelectric conversion element is a circuit element that amplifies the light received from the scintillator and converts it into an electric signal. As the photoelectric conversion element, for example, a photomultiplier tube, a photodiode, or the like is used. The detection element may be an indirect detection type that converts X-rays into light and then detects them, or may be a direct detection type that directly converts X-rays into an electric signal.

A data acquisition circuit 19 is connected to the X-ray detector 15. The data acquisition circuit 19 reads an electric signal corresponding to the X-ray intensity detected by the X-ray detector 15 from the X-ray detector 15 according to the instruction from the gantry control circuit 29, and reads the read electric signal during the view period. Collect raw data with digital values depending on the dose of X-rays over. The data acquisition circuit 19 is realized by, for example, an ASIC (Application Specific Integrated Circuit) equipped with a circuit element capable of generating raw data.

The floodlight 27 projects visible light (flooding laser) onto the top plate inserted in the opening or the subject P placed on the top plate according to the instruction from the gantry control circuit 29. The color of the visible light emitted from the floodlight 27 may be any color such as red, green and blue. Visible light is projected to align the subject P.

The gantry control circuit 29 synchronously synchronizes the high voltage generator 17, the data acquisition circuit 19, the rotary drive device 21, and the sleeper drive device 25 in order to execute X-ray CT imaging according to the imaging conditions from the arithmetic circuit 101 of the console 100. To control. As hardware resources, the gantry control circuit 29 includes a processing device (processor) such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit) and a storage device (Random Access Memory) such as a ROM (Read Only Memory) and a RAM (Random Access Memory). It has a memory). Further, the gantry control circuit 29 includes an ASIC, a field programmable gate array (FPGA), another complex programmable logic device (CPLD), and a simple programmable logic device (Simple Programmable Logic Device). : SPLD) may be realized.

As shown in FIG. 1, the console 100 has an arithmetic circuit 101, a display circuit 103, an input circuit 105, and a storage circuit 107. Data communication between the arithmetic circuit 101, the display circuit 103, the input circuit 105, and the storage circuit 107 is performed via a bus.

The arithmetic circuit 101 has a CPU, a processor such as an MPU or GPU (Graphics Processing Unit), and a memory such as a ROM or RAM as hardware resources. The arithmetic circuit 101 realizes a preprocessing function 111, a reconstruction function 113, an image processing function 115, and a system control function 117 by executing various programs.

In the preprocessing function 111, the arithmetic circuit 101 performs preprocessing such as logarithmic conversion on the raw data transmitted from the gantry 10. The raw data after preprocessing is also called projection data.

In the reconstruction function 113, the arithmetic circuit 101 generates a CT image expressing the spatial distribution of CT values with respect to the subject P based on the raw data after the preprocessing. As the image reconstruction algorithm, an existing image reconstruction algorithm such as an FBP (filtered back projection) method or a successive approximation reconstruction method may be used.

In the image processing function 115, the arithmetic circuit 101 performs various image processing on the CT image reconstructed by the reconstruction function 113. For example, the arithmetic circuit 101 performs three-dimensional image processing such as volume rendering, surface volume rendering, image value projection processing, MPR (Multi-Planer Reconstruction) processing, and CPR (Curved MPR) processing on the CT image to display an image. To generate.

In the system control function 117, the arithmetic circuit 101 comprehensively controls the X-ray computer tomography apparatus according to the present embodiment. Specifically, the arithmetic circuit 101 reads out the control program stored in the storage circuit 107, expands it on the memory, and controls each part of the X-ray computer tomography apparatus according to the expanded control program.

The preprocessing function 111, the reconstruction function 113, the image processing function 115, and the system control function 117 may be mounted by the arithmetic circuit 101 of one board, or may be distributed and mounted by the arithmetic circuits 101 of a plurality of boards. May be done.

The display circuit 103 displays various information such as a CT image and a scan plan. Specifically, the display circuit 103 has a display interface and a display device. The display interface converts data representing a display target into a video signal. The video signal is supplied to the display device. The display device displays a video signal representing a display target. As the display device, for example, a CRT display, a liquid crystal display, an organic EL display, an LED display, a plasma display, or any other display known in the art can be appropriately used. The display device may be provided on the gantry 10 or on the wall surface of the treatment room. Further, the display device may be a projector.

Specifically, the input circuit 105 has an input device and an input interface. The input device receives various commands from the user. As an input device, a keyboard, a mouse, various switches and the like can be used. The input interface supplies the output signal from the input device to the arithmetic circuit 101 via the bus.

The storage circuit 107 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. For example, the storage circuit 107 stores a CT image, a scan plan, and the like. As hardware, the storage circuit 468 may be a drive device or the like that reads and writes various information to and from a portable storage medium such as a CD-ROM drive, a DVD drive, and a flash memory.

FIG. 2 is a diagram showing the appearance of the gantry 10 in the present embodiment. FIG. 3 is a diagram showing a cut surface of the gantry 10 of FIG. 2 including the Z axis. As shown in FIGS. 2 and 3, the gantry 10 has a gantry housing 30 in which an opening 31 having a substantially cylindrical shape is formed. The gantry housing 30 houses a main frame 35 that functions as a fixed portion and a rotating frame 11 that functions as a rotating portion. The main frame 35 supports the rotating frame 11 so as to be continuously rotatable around the Z axis via a bearing. An X-ray tube 13, an X-ray detector 15, and a data acquisition circuit 19 (not shown) are attached to the rotating frame 11. Further, a floodlight (hereinafter referred to as an internal floodlight) 271 is attached to the rotating frame 11 so that visible light is directed toward the opening 31. The internal floodlight 271 projects visible light for directly viewing the reference line of the photographing range or the entire photographing range. A floodlight (hereinafter referred to as an external floodlight) 273 is also attached to the main frame 35 so that visible light is directed toward the opening 31. The external floodlight 273 projects visible light for directly visually recognizing the reference line of the photographing range. When the internal floodlight 271 and the external floodlight 273 are not particularly distinguished, they are simply referred to as a floodlight 27.

Note that FIGS. 2 and 3 illustrate an embodiment in which two internal floodlights 271 are attached to the rotating frame 11, but the X-ray computer tomography apparatus according to the present embodiment is not limited to this. That is, the number of internal floodlights 271 that can be attached to the rotating frame 11 may be any number. Similarly, the number of external floodlights 273 that can be attached to the main frame 35 is not limited to four, and any number may be attached.

As shown in FIGS. 2 and 3, a transmission film 33 is provided on the inner walls 301 and 303 facing the opening 31 of the gantry housing 30. The chamfered portion 301 of the inner walls 301 and 303 is referred to as a central inner wall, and the chamfered portion 303 is referred to as a peripheral inner wall. The chamfering is performed, for example, in order to reduce the feeling of blockage due to the opening 31.

The central inner wall 301 is provided with a gap 371 for passing visible light emitted from the internal floodlight 271 and X-rays generated from an X-ray tube 13 (not shown). Since the internal floodlight 271 and the X-ray tube 13 are attached to the rotating frame 11, the gap 371 is formed over the entire circumference of the Z-axis of the central inner wall 301. A permeable membrane (hereinafter referred to as a central permeable membrane) 331 is attached so as to cover the gap 371. That is, the visible light emitted from the internal floodlight 271 and the X-ray generated from the X-ray tube 13 pass through the central transmission film 331.

The peripheral inner wall 303 is provided with a hole 373 for passing visible light emitted from the external floodlight 273. The hole 373 is formed only in the emission direction of visible light of the external floodlight 273. A permeable membrane (hereinafter referred to as a peripheral permeable membrane) 333 is attached so as to cover the hole 373. Hereinafter, when the central permeable membrane 331 and the peripheral permeable membrane 333 are not particularly distinguished, they are simply referred to as the permeable membrane 33. That is, the visible light emitted from the external floodlight 273 and the X-ray generated from the X-ray tube 13 pass through the peripheral transmission film 333. In other words, the visible light projected from the internal floodlight 271 and the visible light projected from the external floodlight 273 pass through a different transmission film 33.

The transmission film 33 is a wavelength band that transmits visible light emitted from the floodlight 27 and makes it difficult to visually recognize the inside of the gantry housing 30 from the outside, and is a color belonging to the wavelength band excluding the wavelength to which the color of the visible light belongs. Has. As a wavelength band in which the inside of the gantry housing 30 is difficult to see from the outside, specifically, a wavelength band in which the inside of the gantry housing 30 can be shielded from the outside may be used. The central transmissive film 331 and the peripheral transmissive film 333 are the same as long as the central transmissive film 331 transmits the visible light of the internal floodlight 271 and the peripheral transmissive film 333 transmits the visible light of the external floodlight 273. It may have the color of, or it may have a different color. The internal floodlight 271 and the external floodlight 273 may emit visible light of the same color or may emit visible light of different colors. The permeable membrane 33 may be formed of any material as long as it has a color satisfying the above conditions. For example, the permeable membrane 33 is formed of a film made of polyester such as Mylar (registered trademark).

Hereinafter, a method for determining the color of the transmission film 33 will be described in detail.

The color according to this embodiment shall be defined by the wavelength. For convenience, purple belongs to the wavelength band of 380-450 nm, blue to 450-500 nm, green to 500-570 nm, yellow to 570-590 nm, orange to 590-620 nm, and red to 620-750 nm. The wavelength band of a color is not limited to the above relationship, and any wavelength may be associated with a certain color.

As a floodlight for an X-ray computer tomography apparatus, a type capable of projecting red visible light is the mainstream. Compared to red, green and blue are easier for humans to see, but floodlights that can emit green and blue visible light cannot withstand the strong centrifugal force that accompanies the rotation of the rotating frame 11, and are expensive. For this reason, it has not been used in X-ray computer tomography equipment. However, due to technological innovation, it is expected that floodlights capable of projecting green or blue visible light will also be used. Therefore, in the following embodiment, the color of the transmission film 33 with respect to the floodlight 27 that emits green visible light is determined.

The color of the transmissive film 33 is determined based on the wavelength distribution of the weight coefficient of the transmittance of the color that the transmissive film 33 can have and the wavelength distribution of the transmittance for the color that the transmissive film 33 can have (transmission spectrum). To.

FIG. 4 is a diagram showing the wavelength distribution of the weighting factor of the color transmittance that the transmission film 33 can have. The vertical axis of FIG. 4 is defined by the weighting factor, and the horizontal axis is defined by the wavelength [nm]. The weighting factor is a coefficient determined according to the luminous efficiency for calculating the visible light transmittance and the like. Colors belonging to wavelengths with a higher weighting factor are more likely to transmit to all colors. As shown in FIG. 4, the weighting factor has a maximum value in the wavelength band belonging to green, and decreases as the distance from the wavelength corresponding to the maximum value increases. That is, it can be seen that green easily transmits all colors.

Typically, a red transmission film 33, which is the same color for red visible light, is used. Similarly, when a green transmission film 33, which is the same color as green visible light, is used, green easily transmits all colors as described above, so that the inside of the gantry housing 30 can be easily seen from the outside. turn into. Therefore, as the color of the transmission film 33, it is preferable to use a color belonging to a wavelength band other than the green wavelength. Specifically, a color belonging to the wavelength band to which the weight coefficient of the weight coefficient threshold TH1 or less belongs can be a candidate for the color of the transmission film 33. As the color belonging to the wavelength band to which the weighting factor of the threshold value TH1 or less belongs, for example, purple, blue, orange and red are listed as candidates.

FIG. 5 is a diagram showing a wavelength distribution (transmission spectrum) of the transmittance for each color that the transmission film 33 can have. The vertical axis of FIG. 5 is defined by the transmittance, and the horizontal axis is defined by the wavelength [nm]. The solid line indicates the blue transmission film 33, the dotted line indicates the green transmission film 33, the broken line indicates the yellow transmission film 33, and the alternate long and short dash line indicates the red transmission film 33. As shown in FIG. 5, the transition of the wavelength distribution of the transmittance is different for each color that the transmission film 33 can have. In general, yellow and red remain constant at low transmittance in a wavelength band lower than the wavelength band to which their color belongs, and their transmittance rises sharply in the vicinity of the wavelength band to which their color belongs. In the wavelength band higher than the wavelength band to which the color belongs, the transmittance remains constant at high transmittance. Blue and green have a medium transmittance peak near the wavelength band to which their color belongs, and the transmittance rises sharply near the wavelength band to which red belongs, and in the wavelength band higher than the wavelength band to which red belongs. It stays constant with high transmittance.

Specifically, as shown in FIG. 5, yellow has a low transmittance of about 0.1 from 350 nm to about 450 nm, the transmittance increases sharply at about 450 nm, and 0. It changes with a high transmittance of about 8. Red has a low transmittance of about 0.1 from 350 nm to about 650 nm, a sharp increase in transmittance at about 650 nm, and a high transmittance of about 0.8 from about 650 nm onward. The blue color gradually increases from a transmittance of 0.1 to about 350 nm to 380 nm, changes with a relatively high transmittance of about 0.5 from 380 nm to 450 nm, and has a transmittance of 0 from 450 nm to about 600 nm. It descends toward 1 and changes at a low transmittance of about 0.1 from 600 nm to 700 nm, rapidly increases at about 700 nm, and changes at a high transmittance of about 0.8 from about 700 nm onward. Green has a low transmittance of about 0.1 from 350 nm to 480 nm, a relatively high transmittance of about 0.5 from 380 nm to 450 nm, and a transmittance of 0 from 450 nm to 520 nm. It rises toward .4, decreases to a transmittance of about 0.1 from 520 nm to 600 nm, changes to a low transmittance of about 0.1 from 600 nm to about 700 nm, and the transmittance rises sharply at about 700 nm. It changes with a high transmittance of about 0.8 from about 700 nm.

As shown in FIG. 5, when the transmissive film 33 is blue, the transmittance in the green wavelength band is about 0.3, so that green visible light can be transmitted to some extent. When the transmissive film 33 is green, the transmittance in the green wavelength band is about 0.4, so that green visible light can be transmitted to some extent. When the transmissive film 33 is yellow, the transmittance in the green wavelength band is about 0.7, so that green visible light can be satisfactorily transmitted. When the transmissive film 33 is red, the transmittance in the green wavelength band is about 0.1, so that almost no green visible light can be transmitted. The wavelength distribution of orange transmittance is a superposition of the wavelength distribution of red transmittance and the wavelength distribution of yellow transmittance. Therefore, when the transmissive film 33 is orange, the transmittance in the green wavelength band is about 0.3, so that green visible light can be transmitted to some extent. The wavelength distribution of purple transmittance is a superposition of the wavelength distribution of red transmittance and the wavelength distribution of blue transmittance. Therefore, when the transmissive film 33 is purple, the transmittance in the green wavelength band is about 0.2, so that green visible light can be transmitted to some extent.

Specifically, when determining a color candidate for the transmittance film 33 from the viewpoint of transmittance, the transmittance threshold TH2 is set in the wavelength distribution of the transmittance. When the visible light of the floodlight 27 is green, in the wavelength distribution of the transmittance, a color having a transmittance of the threshold TH2 or more in the wavelength band RW2 to which the green belongs is determined as a color candidate of the transmission film 33. For example, when the visible light of the floodlight 27 is green, the threshold value TH2 may be set to about 0.2. Therefore, purple, blue, green, orange, and yellow are listed as color candidates for the transmission film 33.

As described above, when the visible light of the floodlight 27 is green, purple, blue, orange and red are selected as color candidates of the transmission film 33 from the viewpoint of the weight factor, and the transmission film 33 is selected from the viewpoint of the transmittance. Purple, blue, green, orange and yellow are selected as color candidates. Therefore, when the visible light of the floodlight 27 is green, the color of the transmission film 33 is determined to be one of purple, blue, and orange belonging to a wavelength band other than the wavelength of green, which is the color of the visible light. ..

For example, when an internal floodlight 271 that emits green visible light is used, the color of the central transmission film 331 may be selected to be purple, blue, or orange. As a result, the central transmissive film 331 can transmit the green visible light emitted from the internal floodlight 271 and prevent the inside of the gantry housing 30 from being visually recognized from the outside. Therefore, since the central transmissive film 331 can satisfactorily transmit the green visible light emitted from the internal floodlight 271, the user can easily align the patient P using the internal floodlight 271. In addition, since it is possible to prevent the inside of the gantry housing 30 from being visually recognized from the outside, it is possible to prevent the patient's head from moving due to the patient P consciously or unconsciously following the rotating frame 11 with his / her eyes. , Body movement artifacts can be reduced.

The color of the peripheral permeable membrane 333 can be determined in the same manner as the central permeable membrane 331. That is, the peripheral transmission film 333 is a wavelength band that allows visible light emitted from the external floodlight 273 to be transmitted and shields the inside of the gantry housing 30 from the outside, excluding the wavelength to which the color of the visible light belongs. It has a color that belongs to the wavelength band. For example, when the color of the external floodlight 273 is green, the color of the peripheral transmission film 333 may be selected to be purple, blue, or orange. As a result, the peripheral transmissive film 333 can transmit the green visible light emitted from the external floodlight 273 while hindering the visual recognition of the inside of the gantry housing 30.

The method for determining the color of the transmission film 33 is not limited to the case where the visible light of the floodlight 27 is green, and can be applied to visible light of any color such as blue and red. As shown in FIGS. 4 and 5, when the visible light is blue, the color of the transmission film 33 may be selected to be blue or purple. When the visible light is red, the color of the transmission film 33 may be selected to be red, orange, or purple. When a color belonging to a wavelength band other than the wavelength of the visible light color is selected as the color of the transmission film 33, the color of the transmission film 33 is selected to be purple for blue visible light and red visible light. On the other hand, the color of the transmission film 33 may be selected to be orange or purple.

The visible light of the internal floodlight 271 and the visible light of the external floodlight 273 may have different colors. For example, the visible light of the internal floodlight 271 may be green and the visible light of the external floodlight 273 may be red. In this case, as described above, the color of the central transmission film 331 is preferably selected to be purple, blue or orange, and the color of the peripheral transmission film 333 is preferably selected to be red, orange or purple. As a result, both the visible light of the internal floodlight 271 and the visible light of the external floodlight 273 can be visually recognized satisfactorily, and the inside of the gantry housing 33 can be obstructed from being visually recognized. Further, since the internal floodlight 271 and the external floodlight 273 can use visible light of different colors, it is possible to prevent the internal floodlight 271 and the external floodlight 273 from being confused by the color.

(Application example)
In the above embodiment, the color of visible light transmitted through one transmission film 33 is one color. However, this embodiment is not limited to this. For example, the color of visible light transmitted through the central transmission film 331 is not limited to one color, and may be two colors or three or more colors. Hereinafter, application examples of this embodiment will be described. In the following description, components having substantially the same functions as those in the above embodiment are designated by the same reference numerals and will be described in duplicate only when necessary.

FIG. 6 is a diagram showing a cut surface including the Z axis of the gantry 10 according to the application example. As shown in FIG. 6, in the gantry 10 according to the application example, two types of internal floodlights 271,275 are provided on the rotating frame 11. The internal floodlight 271 emits visible light for directly visually recognizing the reference line of the photographing range. The internal floodlight 275 emits visible light for directly viewing the entire shooting range. The visible light of the internal floodlight 271 and the visible light of the internal floodlight 275 pass through the same central transmission film 331.

The color of the transmission film 331 is a color that can hinder the visibility from the outside inside the gantry housing 30 while transmitting both the visible light emitted from the internal floodlight 271 and the visible light emitted from the internal floodlight 275. Be selected. For example, when a type that emits red visible light is used as the internal floodlight 271 and a type that emits green visible light is used as the internal floodlight 275, the central transmission film 331 according to the application example is used. The method of determining the color of the light is explained.

From the wavelength distribution of the weighting factor in FIG. 4, purple, blue, orange, and red are selected as candidates for the central transmissive film 331. From the wavelength distribution of the transmittance in FIG. 5, purple, blue, green, yellow, orange, and red are selected as candidates for the central transmissive film 331 for red visible light, and the central transmissive film 331 for green visible light is selected. Purple, blue, orange and red are selected as candidates for. Therefore, from the wavelength distribution of the transmittance in FIG. 5, purple, blue, orange, and red are selected as candidates for the central transmissive film 331. Therefore, when a type that emits red visible light is used as the internal floodlight 271 and a type that emits green visible light is used as the internal floodlight 275, the color of the central transmissive film 331 is purple, blue, orange, or red. Will be decided. When a color to which a wavelength band other than the wavelength of the visible light color of the internal floodlight 271 and the internal floodlight 275 belongs is used as the color of the central transmissive film 331, the color of the central transmissive film 331 is purple, blue, or orange. Will be decided. Therefore, since the central transmissive film 331 can satisfactorily transmit the red visible light projected from the internal floodlight 271 and the green visible light projected from the internal floodlight 275, the user can use the internal floodlight 271 and the internal floodlight 275. It is possible to easily align the patient P using the above. In addition, since it is possible to prevent the inside of the gantry housing 30 from being visually recognized from the outside, it is possible to prevent the patient's head from moving due to the patient P consciously or unconsciously following the rotating frame 11 with his / her eyes. , Body movement artifacts can be reduced. Further, since the internal floodlight 271 and the internal floodlight 275 can use visible light of different colors, it is possible to prevent the internal floodlight 271 and the internal floodlight 275 from being confused by the color.

In the above embodiment, the gantry 10 is assumed to be the gantry of the X-ray computer tomography apparatus. However, this embodiment is not limited to this. That is, any pedestal having the floodlight 27 and the transmissive film 33 can be applied to a pedestal of a medical image diagnostic device that performs medical imaging based on any imaging principle, such as a magnetic resonance imaging device or a nuclear medicine diagnostic device. ..

According to at least one embodiment described above, it is possible to reduce the visibility into the gantry housing while maintaining the visibility of the visible light emitted from the floodlight.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

10 ... gantry, 11 ... rotating frame, 13 ... X-ray tube, 15 ... X-ray detector, 17 ... high voltage generator, 19 ... data acquisition circuit, 21 ... rotating drive device, 23 ... sleeper, 25 ... sleeper drive device , 27 ... floodlight, 29 ... gantry control circuit, 30 ... gantry housing, 31 ... opening, 33 ... transmissive film, 33 ... central transmissive film, 35 ... mainframe, 100 ... console, 101 ... arithmetic circuit, 103 ... display Circuit, 105 ... Input circuit, 107 ... Storage circuit, 111 ... Preprocessing function, 113 ... Reconstruction function, 115 ... Image processing function, 117 ... System control function, 271 ... Internal floodlight, 273 ... External floodlight, 275 ... Internal floodlight , 301 ... Central inner wall, 303 ... Peripheral inner wall, 331 ... Central permeable film, 333 ... Peripheral permeable film, 371 ... Gap, 373 ... Hole.

Claims (15)

An X-ray computer tomography apparatus comprising a gantry device for performing X-ray CT imaging and a processing apparatus for controlling the gantry device.
The gantry device
A gantry housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for X-ray CT imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The visible light is green and
The permeable membrane is orange, blue or purple,
X-ray computer tomography equipment. An X-ray computer tomography apparatus comprising a gantry device for performing X-ray CT imaging and a processing apparatus for controlling the gantry device.
The gantry device
A gantry housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for X-ray CT imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The visible light is blue and
The permeable membrane is purple,
X-ray computer tomography equipment. An X-ray computer tomography apparatus comprising a gantry device for performing X-ray CT imaging and a processing apparatus for controlling the gantry device.
The gantry device
A gantry housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for X-ray CT imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The transmissive film has a specific color based on the wavelength distribution of the weight factor of the color transmittance and the wavelength distribution of the transmittance for the color.
The specific color belongs to the color of the visible light in a specific wavelength band having a weight factor of 1 or less and a transmittance of 2 or more with respect to the visible light. Belonging to the wavelength band excluding wavelength,
X-ray computer tomography equipment. The visible light is green and
The particular color is orange, blue or purple,
The X-ray computer tomography apparatus according to claim 3 . The visible light is blue and
The particular color is purple ,
The X-ray computer tomography apparatus according to claim 3 . The floodlight has a first floodlight that emits visible light of a first color that passes through the transmission film and a second floodlight that transmits visible light of a second color that passes through the transmission film and is different from the first color. With a floodlight,
The transmissive film has the particular color belonging to a wavelength band that transmits both visible light of the first color and visible light of the second color.
The X-ray computer tomography apparatus according to claim 3 . The first color is one of red, green and blue.
The second color is a color different from the one of red, green, and blue.
The permeable membrane has an orange or purple color.
The X-ray computer tomography apparatus according to claim 6. A rotating frame provided inside the gantry housing and equipped with an X-ray tube and an X-ray detector arranged across the opening, and
A main frame provided inside the gantry housing and rotatably supporting the rotating frame around the central axis of the opening is further provided.
The first floodlight and the second floodlight are provided on the rotating frame.
The X-ray computer tomography apparatus according to claim 6. The X-ray computer tomography apparatus according to claim 3 , wherein the specific wavelength band is a wavelength band capable of shielding the inside of the gantry housing from the outside. The floodlight is a first floodlight provided in the gantry housing and emitting visible light of the first color, and a second color visible light beam provided in the gantry housing and different from the first color. With a second floodlight that emits
The transmissive film is attached to the inner wall portion of the gantry housing facing the opening, and the first transmissive film that transmits the first visible light emitted from the first floodlight and the inner wall portion. With a second transmission film, which is attached to and transmits a second visible light emitted from the second floodlight.
The first transmission film has a color belonging to a wavelength band excluding the wavelength to which the color of the first visible light belongs in the specific wavelength band.
The second transmission film has a color belonging to a wavelength band other than the wavelength to which the color of the second visible light belongs in the specific wavelength band .
The X-ray computer tomography apparatus according to claim 3 . A rotating frame provided inside the gantry housing and equipped with an X-ray tube and an X-ray detector arranged across the opening, and
A main frame provided inside the gantry housing and rotatably supporting the rotating frame around the central axis of the opening is further provided.
The first floodlight and the second floodlight are provided on the rotating frame.
The X-ray computer tomography apparatus according to claim 10. A rotating frame provided inside the gantry housing and equipped with an X-ray tube and an X-ray detector arranged across the opening, and
A main frame provided inside the gantry housing and rotatably supporting the rotating frame around the central axis of the opening is further provided.
The first floodlight is provided on the rotating frame.
The second floodlight is provided on the mainframe.
The X-ray computer tomography apparatus according to claim 10. A pedestal housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for medical imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The visible light is green and
The permeable membrane is orange, blue or purple,
Mount device. A pedestal housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for medical imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The visible light is blue and
The permeable membrane is purple,
Mount device. A pedestal housing that has an opening into which the subject is inserted and is equipped with an imaging mechanism for medical imaging.
At least one floodlight provided in the gantry housing and emitting visible light,
It has a transmissive film attached to an inner wall portion of the gantry housing facing the opening and transmitting visible light emitted from the floodlight.
The transmissive film has a specific color based on the wavelength distribution of the weight factor of the transmittance of the color and the wavelength distribution of the transmittance for the color.
The specific color belongs to the color of the visible light in a specific wavelength band having a weight factor of 1 or less and a transmittance of 2 or more with respect to the visible light. Belonging to the wavelength band excluding wavelength,
Mount device.

Images