X-ray diagnostic apparatus and method

Abstract

To achieve a simple structure which can translate a C arm and is smaller than an X-Y stage structure.SOLUTION: An X-ray diagnostic apparatus includes a base table, a first support arm, a second support arm, a C arm, and translation control means. The base table is supported by a rail arranged on a ceiling and is movable in a longitudinal direction of the rail. The first support arm is supported by the base table to be rotatable about a first rotation axis in a vertical direction. The second support arm is supported by the first support arm to be rotatable about a second rotation axis in the vertical direction. The C arm is supported by the second support arm. The translation control means translates the C arm in a width direction of the rail by controlling movements of the base table, rotation by the first rotation axis, and rotation by the second rotation axis.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an X-ray diagnostic apparatus and an angiography CT (Computed Tomography) apparatus.

Background Art

[0002] As methods of X-ray diagnostic apparatuses for the cardiovascular system, a ceiling suspension type that supports a C-arm from the ceiling surface and a floor-mounted type that supports a C-arm from the floor surface are known.

[0003] The ceiling suspension type includes an X-Y stage structure in which a stage movable in the longitudinal direction of a ceiling rail arranged on the ceiling supports the C-arm so as to be movable also in the width direction of the ceiling rail. That is, the ceiling suspension type supports the C-arm so as to be translatable in the longitudinal direction and the width direction of the ceiling rail by the X-Y stage structure. In addition to this, the ceiling suspension type has a configuration having a rotation axis in the X-Y stage structure, and makes the isocenter axis of the C-arm rotatable and linearly movable. Here, the isocenter axis referred to herein corresponds to the imaging axis when it is on the same straight line as the rotation axis. The imaging axis is an axis passing through the X-ray focal point of the X-ray tube held by the C-arm and the center of the detection surface of the X-ray detector held by the C-arm.

[0004] The floor-mounted type includes a first support arm rotatably supported horizontally by a first rotation axis from the floor surface, and a second support arm rotatably supported horizontally by a second rotation axis from the tip of the first support arm. The floor-mounted type makes the isocenter axis of the C-arm linearly movable while rotating by a configuration that interlocks such two rotation axes. Here, the isocenter axis referred to herein corresponds to the vertical imaging axis that can be arranged on the same straight line as the first rotation axis.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Although the X-ray diagnostic apparatus as described above usually has no particular problem, according to the study by the present inventor, there is room for improvement in the following points.

[0007] In the case of the ceiling-suspended type, in order to enable the C-arm to be translated parallel to the longitudinal direction and the width direction of the ceiling rail, there is an inconvenience that a large and complex X-Y stage structure is required.

[0008] In the case of the floor-standing type, unlike the ceiling-suspended type, there is an inconvenience that the C-arm cannot be translated.

[0009] The object is to enable the C-arm to be translated and to realize a structure that is smaller and simpler than the X-Y stage structure.

Means for Solving the Problems

[0010] The X-ray diagnostic apparatus according to the embodiment includes a base, a first support arm, a second support arm, a C-arm, and a translation control means. The base is supported by a rail disposed on the ceiling and is movable in the longitudinal direction of the rail. The first support arm is supported by the base so as to be rotatable about a first rotation axis in the vertical direction. The second support arm is supported by the first support arm so as to be rotatable about a second rotation axis in the vertical direction. The C-arm is supported by the second support arm. The translation control means translates the C-arm along the width direction of the rail by controlling the movement of the base, the rotation about the first rotation axis, and the rotation about the second rotation axis.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, each embodiment will be described with reference to the drawings.

[0013] <First Embodiment> FIG. 1 is a block diagram showing the configuration of the X-ray diagnostic apparatus according to the first embodiment, and FIGS. 2 and 3 are an external view and a plan view of the X-ray diagnostic apparatus. The X-ray diagnostic apparatus 1 includes an imaging apparatus 10, a couch apparatus 30, and a console apparatus 40. The imaging apparatus 10 includes a high voltage generator 11, an X-ray generation unit 12, an X-ray detector 13, a C-arm 14, a state detector 141, and a C-arm drive device 142.

[0014] The high voltage generator 11 generates a high voltage to be applied between the anode and the cathode in order to accelerate the thermoelectrons generated from the cathode of the X-ray tube, and outputs the high voltage to the X-ray tube.

[0015] The X-ray generation unit 12 includes an X-ray tube that irradiates the subject P with X-rays, an ROI (Region Of Interest) filter having a function of attenuating or reducing the irradiated X-ray dose, and an X-ray aperture.

[0016] The X-ray tube is a vacuum tube that generates X-rays. The thermoelectrons emitted from the cathode (filament) are accelerated by a high voltage, and the accelerated electrons are collided with a tungsten anode to generate X-rays.

[0017] The ROI filter is located between the X-ray tube and the X-ray aperture and is composed of metal plates such as copper and aluminum. The ROI filter has an opening area at least in part, for example, in the central part, and attenuates X-rays outside the opening area. Therefore, the ROI filter fully transmits X-rays in the X-ray passing area of the opening area and attenuates and transmits X-rays in other areas. The ROI filter is driven by a drive device (not shown) according to the region of interest input by the operator from the input interface 43.

[0018] The X-ray aperture is located between the X-ray tube and the X-ray detector 13 and is composed of a lead plate as a metal plate. The X-ray aperture narrows down the X-rays generated by the X-ray tube so that only the region of interest of the subject P is irradiated by shielding the X-rays outside the opening area. For example, the X-ray aperture has four aperture vanes, and by sliding these aperture vanes, the shielded area of the X-rays can be adjusted to an arbitrary size. The aperture vanes of the X-ray aperture are driven by a drive device (not shown) according to the region of interest input by the operator from the input interface 43.

[0019] The X-ray detector 13 detects the X-rays that have passed through the subject P. As such an X-ray detector 13, those that directly convert X-rays into electric charges and those that convert them into light and then into electric charges can be used. Here, the former will be described as an example, but the latter may also be used. That is, the X-ray detector 13 includes, for example, a planar FPD (Flat Panel Detector) that converts and accumulates the X-rays passing through the subject P into electric charges, and a gate driver that generates drive pulses for reading out the charges accumulated in the FPD. The size of the FPD is generally 8 to 12 inches. The FPD is configured by two-dimensionally arranging minute detection elements in the column direction and the line direction. Each detection element includes a photoelectric film that senses X-rays and generates charges according to the incident X-ray dose, a charge storage capacitor that stores the charges generated in the photoelectric film, and a TFT (Thin Film Transistor) that outputs the charges stored in the charge storage capacitor at a predetermined timing. The accumulated charges are sequentially read out by the drive pulses supplied by the gate driver.

[0020] A projection data generation circuit and a projection data storage circuit (not shown) are provided downstream of the X-ray detector 13. The projection data generation circuit includes a charge-voltage converter that converts charges read out in parallel from the FPD on a row-by-row or column-by-column basis into voltages, an A / D converter that converts the output of the charge-voltage converter into a digital signal, and a parallel-serial converter that converts the digitally converted parallel signal into a time-series serial signal. The projection data generation circuit supplies this serial signal as time-series projection data to the projection data storage circuit. The projection data storage circuit sequentially stores the time-series projection data supplied from the projection data generation circuit to generate two-dimensional projection data. This two-dimensional projection data is stored in the memory 41.

[0021] The C-arm 14 has a configuration that enables X-ray imaging of the subject P on the top plate 33 by holding the X-ray generation unit 12 and the X-ray detector 13 so as to face each other with the subject P and the top plate 33 interposed therebetween.

[0022] As shown in FIG. 2, the base 14a is supported by a rail r1 installed on the ceiling surface and is movable along the longitudinal direction (X direction) of the rail r1. As a result, the base 14a can move horizontally on the ceiling surface. The fulcrum 14b1 of the base 14a is connected to the proximal end of the first support arm 14c1, and by rotating about a first rotation axis z1 extending vertically from this fulcrum 14b1, the first support arm 14c1 is rotated horizontally with respect to the ceiling surface. That is, the first support arm 14c1 is supported by the base 14a so as to be rotatable about the vertical first rotation axis z1. The fulcrum 14b2 at the tip of the first support arm 14c1 is connected to the upper end of the second support arm 14c2, and by rotating about a second rotation axis z2 extending vertically from this fulcrum 14b2, the second support arm 14c2 is rotated horizontally with respect to the ceiling surface. That is, the second support arm 14c2 is supported by the first support arm 14c1 so as to be rotatable about the vertical second rotation axis z2. The connection portion 14d at the lower end of the second support arm 14c2 slidably supports the C-arm 14 along the arc shape of the C-arm 14 and rotatably holds the C-arm 14 about an arm main rotation axis Rc extending parallel to the ceiling surface. In this slidable and rotatable supported state, the C-arm 14 is supported by the second support arm 14c2. Note that the imaging axis passing through the X-ray focal point of the X-ray generation unit 12 and the center of the detection surface of the X-ray detector 13 is designed to intersect at a single point with the arm main rotation axis Rc and an arm slide axis (not shown). The arm slide axis is an axis that can be regarded as the rotation center of the imaging axis when the C-arm 14 slides along its arc shape. The absolute coordinates (position in the imaging room coordinate system) of the intersection point (intersection) do not displace even when the C-arm 14 rotates about the arm main rotation axis Rc or the arm slide axis in a state where the base 14a and the first and second support arms 14c1, 14c2 are stationary. The absolute coordinates of the intersection point are generally referred to as the isocenter IS. Also, in this specification, the imaging axis in the vertical direction is also referred to as the isocenter axis zS. The isocenter axis zS is located on the extension line of the first rotation axis z1 in the initial state of rotation by the first rotation axis z1, the second rotation axis z2, the arm main rotation axis Rc, and the arm slide axis.At this time, on the horizontal plane (plan view), the isocenter axis zS overlaps with the first rotation axis z1. That is, the horizontal distance L from the first rotation axis z1 to the second rotation axis z2 and the horizontal distance L from the isocenter axis zS to the second rotation axis z2 are equal to each other.

[0023] From the above configuration, as shown in FIG. 3, by controlling the movement of the base 14a, the rotation by the first rotation axis z1, and the rotation by the second rotation axis z2, the isocenter axis zS can be linearly moved along the width direction (Y direction) of the rail r1. Further, by controlling the movement of the base 14a, the rotation by the first rotation axis z1, and the rotation by the second rotation axis z2, the C-arm 14 can be translated along the width direction (Y direction) of the rail r1. In FIG. 3, “CL” indicates a straight line connecting the second rotation axis z2 and the isocenter axis zS on the horizontal plane. Note that the C-arm 14 or the base 14a can also move in a direction approaching or separating from the ceiling surface in addition to the above. Also, the names of the respective members and the like may be changed as appropriate. For example, the base 14a may be called a “ceiling traveling frame”. The rail r1 may be called a “first rail”, a “ceiling rail”, a “track”, or a “linear track”. The first support arm 14c1 may be called a “ceiling support arm”. The second support arm 14c2 may be called a “support column” or a “support column portion”.

[0024] Returning to FIG. 1, the C-arm 14 is provided with a plurality of power sources corresponding to the operations related to the base 14a, the first rotation axis z1, the second rotation axis z2, the arm main rotation axis Rc, and the arm slide axis at appropriate locations. These power sources constitute the C-arm drive device 142. The C-arm drive device 142 reads the drive signal from the drive control function 442 and moves the C-arm 14 in a sliding motion, a rotational motion, and a linear motion. Further, the C-arm 14 is provided with state detectors 141 for detecting information on its angle, posture, and position, respectively. The state detector 141 is composed of, for example, a potentiometer for detecting a rotation angle or a movement amount, an encoder which is a position detection sensor, etc. As the encoder, for example, a so-called absolute encoder such as a magnetic type, a brush type, or an optoelectronic type can be used. Also, as the state detector 141, various types of position detection mechanisms such as a rotary encoder that outputs a rotational displacement as a digital signal or a linear encoder that outputs a linear displacement as a digital signal can be appropriately used.

[0025] The bed device 30 is a device for placing and moving the subject P, and includes a base 31, a bed drive device 32, a top plate 33, and a support frame 34.

[0026] The base 31 is a housing installed on the floor surface and supporting the support frame 34 so as to be movable in the vertical direction (Z direction).

[0027] The bed drive device 32 is housed in the housing of the bed device 30 and is a motor or an actuator that moves the top plate 33 on which the subject P is placed in the longitudinal direction (Y direction) of the top plate 33. The bed drive device 32 reads the drive signal from the drive control function 442 and moves the top plate 33 in a horizontal direction or a vertical direction with respect to the floor surface. When the C-arm 14 or the top plate 33 moves, the positional relationship of the imaging axis with respect to the subject P changes. Note that the bed drive device 32 may move the support frame 34 in the longitudinal direction of the top plate 33 in addition to the top plate 33.

[0028] The top plate 33 is provided on the upper surface of the support frame 34 and is a plate on which the subject P is placed.

[0029] The support frame 34 is provided above the base 31 and supports the top plate 33 so as to be slidable along its longitudinal direction.

[0030] The console device 40 includes a memory 41, a display 42, an input interface 43, and a processing circuit 44.

[0031] The memory 41 includes a memory main body for recording electrical information such as an HDD (Hard Disk Drive), and peripheral circuits such as a memory controller and a memory interface associated with the memory main body. The memory 41 stores, for example, a program executed by the processing circuit 44, an X-ray image generated by the processing circuit 44, data used for the processing of the processing circuit 44, data during processing, and data after processing.

[0032] The display 42 includes a display main body for displaying medical images and the like, an internal circuit for supplying a display signal to the display main body, and peripheral circuits such as a connector and a cable for connecting the display main body and the internal circuit. The internal circuit generates display data by superimposing additional information such as subject information and projection data generation conditions on the image data supplied from the image processing function 444 of the processing circuit 44, performs D / A conversion and TV format conversion on the obtained display data, and displays it on the display main body.

[0033] The input interface 43 performs input of subject information, setting of X-ray imaging conditions including X-ray irradiation conditions, input of various command signals, etc. The input interface 43 is realized, for example, by a trackball, a switch button, a mouse, a keyboard, a touch pad for performing an input operation by touching an operation surface, and a touch panel display in which a display screen and a touch pad are integrated, etc. for performing, for example, a movement instruction of the C-arm 14, setting of a region of interest (ROI). The input interface 43 is connected to the processing circuit 44, converts an input operation received from an operator into an electrical signal, and outputs it to the processing circuit 44. Note that in this specification, the input interface 43 is not limited to those provided with physical operation components such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the apparatus and outputs this electrical signal to the processing circuit 44 is also included in the example of the input interface 43.

[0034] The processing circuit 44 is a processor that realizes a system control function 441, a drive control function 442, an X-ray control function 443, an image processing function 444, and a display control function 445 corresponding to a program by calling and executing the program in the memory 41. Although FIG. 1 illustrates that the system control function 441, the drive control function 442, the X-ray control function 443, the image processing function 444, and the display control function 445 are realized by a single processing circuit 44, it is also possible to configure a processing circuit by combining a plurality of independent processors and realizing each function by each processor executing a program. Further, the system control function 441, the drive control function 442, the X-ray control function 443, the image processing function 444, and the display control function 445 may be called a system control circuit, a drive control circuit, an X-ray control circuit, an image processing circuit, and a display control circuit, respectively, and may be implemented as individual hardware circuits.

[0035] The system control function 441, for example, once stores information such as a command signal from the operator input from the input interface 43 and various initial setting conditions, and then transmits this information to each processing function of the processing circuit 44.

[0036] The drive control function 442 controls the C-arm drive device 142 and the bed drive device 32 by using, for example, information regarding the drive of the C-arm 14 and the top plate 33 input from the input interface 43.

[0037] Here, the drive control function 442 has a translation control function for translating the C-arm 14 in parallel along the width direction of the rail r1 by controlling the movement of the base 14a, the rotation by the first rotation axis z1, and the rotation by the second rotation axis z2. When translating the C-arm 14 in parallel along the width direction of the rail r1, this translation control function may control the rotations by the first rotation axis z1 and the second rotation axis z2 to the same angle θ with respect to each other and control the movement of the base 14a. When the horizontal distance between the first rotation axis z1 and the second rotation axis z2 is L, the same angle is θ, and the movement distance of the base 14a is D, the translation control function may control the movement of the base 14a based on the relationship D = L - L cos θ. Further, the translation control function in the drive control function 442 is an example of the translation control means described in the claims.

[0038] The X-ray control function 443 reads information from, for example, the system control function 441 and controls X-ray irradiation conditions such as tube current, tube voltage, and irradiation time in the high-voltage generator 11.

[0039] The image processing function 444 acquires projection data from the memory 41, performs image processing such as filtering processing on the projection data to generate X-ray image data, and stores the X-ray image data in the memory 41. Further, the image processing function 444 performs composite processing, subtraction (subtraction) processing, etc. on the obtained plurality of X-ray image data and stores the obtained X-ray image data in the memory 41.

[0040] The display control function 445 reads a signal from, for example, the system control function 441, acquires desired X-ray image data from the memory 41, and performs control such as displaying it on the display 42.

[0041] Next, the operation of the X-ray diagnostic apparatus configured as described above will be described with reference to the flowchart of FIG. 4 and the schematic diagrams of FIGS. 5 to 7. The following description mainly concerns the operation when moving the C-arm 14 along the body axis Y of the subject P placed on the top plate 33.

[0042] In step ST1, the processing circuit 44 of the X-ray diagnostic apparatus 1 moves the base 14a via the C-arm driving device 142 so that the isocenter axis zS of the C-arm 14 is aligned with the body axis Y of the subject P on the top plate 33 in accordance with the operation of the input interface 43 by the operator.

[0043] After the end of step ST1, as shown in FIG. 5(b) or FIG. 6(b), the isocenter axis zS of the C-arm 14 is located on the body axis Y of the subject P. Also, on the horizontal plane, the angle formed by the straight line CL connecting the second rotation axis z2 and the isocenter axis zS and the body axis Y of the subject P is 90 degrees. That is, the C-arm 14 is arranged in a true lateral position from the left side (or right side) of the subject P. At this time, on the horizontal plane (plan view), the isocenter axis zS overlaps with the first rotation axis z1. Also, the horizontal distance L from the first rotation axis z1 to the second rotation axis z2 is equal to the horizontal distance L from the isocenter axis zS to the second rotation axis z2.

[0044] Next, in step ST2, the drive control function 442 of the processing circuit 44 controls the rotation by the first rotation axis z1 and the rotation by the second rotation axis z2, as shown in FIG. 5(a) or FIG. 5(c), for example, in accordance with the operation of the input interface by the operator. Thereby, the drive control function 442 linearly moves the isocenter axis zS of the C-arm 14 along the width direction of the rail r1 via the C-arm driving device 142. In the case shown in FIG. 5, the drive control function 442 controls the rotation by the first rotation axis z1 as the angle θ and the rotation by the second rotation axis z2 as the angle 2θ.

[0045] Alternatively, in step ST2, the drive control function 442 controls the movement of the base 14a, the rotation by the first rotation axis z1, and the rotation by the second rotation axis z2 as shown in FIGS. 6(a) or 6(c), for example, in response to an operation of the input interface by the operator. Thereby, the drive control function 442 translates the C-arm 14 along the width direction of the rail r1 via the C-arm drive device 142. In the case shown in FIG. 6, the drive control function 442 controls the rotations by the first rotation axis z1 and the second rotation axis z2 to the same angle θ with each other and controls the movement of the base 14a. Also, in the case shown in FIG. 6, the movement distance of the base 14a moving along the longitudinal direction of the rail r1 is defined as D1, and the drive control function 442 controls the movement of the base 14a based on the relationship D1 = L - L cos θ. As can be seen from FIG. 6, the C-arm 14 is translated by controlling the rotations by the first rotation axis z1 and the second rotation axis z2 to the same angle θ with each other. Also, by controlling the movement of the base 14a, the direction of the translation of the C-arm 14 is controlled in the width direction of the rail r1.

[0046] Note that the operation shown in FIG. 6 can be similarly performed even when the orientations of the top plate 33 and the subject P are rotated 90 degrees in the horizontal direction as shown in FIGS. 7(b) to 7(a) or 7(c). That is, the longitudinal direction of the rail r1 and the axis of symmetry Y of the subject P may not be limited to being orthogonal to each other, but may be parallel to each other. Also, the operation shown in FIG. 5 can be similarly performed even when the orientations of the top plate 33 and the subject P are rotated 90 degrees in the horizontal direction (not shown).

[0047] After the end of step ST2, in step ST3, the X-ray diagnostic apparatus 1 performs X-ray imaging. In the case of the operation shown in FIG. 5, since the angle formed by the straight line CL corresponding to the sliding direction of the C-arm 14 and the body axis Y of the subject P is not 90 degrees, X-ray imaging without the C-arm sliding operation is performed.

[0048] On the other hand, in the case of the operation shown in FIG. 6, since the angle formed by the straight line CL corresponding to the sliding direction of the C-arm 14 and the body axis Y of the subject P is 90 degrees, X-ray imaging involving the C-arm sliding operation can be performed. For example, various imaging methods such as rotational DSA imaging (R-DSA), three-dimensional DSA imaging (3D-DSA), and three-dimensional LCI imaging (3D-LCI) by the C-arm sliding operation become possible. Note that DSA is an abbreviation for Digital Subtraction Angiography, and LCI is an abbreviation for Low Contrast Imaging.

[0049] After the end of step ST3, in step ST4, if the X-ray diagnostic apparatus 1 performs X-ray imaging at another position on the body axis Y of the subject P when the examination is not completed by the X-ray imaging in step ST3 (ST4; No), the process returns to step ST2.

[0050] On the other hand, in step ST4, if the examination is completed by the X-ray imaging in step ST3 (ST4; Yes), the X-ray diagnostic apparatus 1 proceeds to step ST5.

[0051] In step ST5, the drive control function 442 controls the movement of the base 14a, for example, in response to an operation of the input interface by the operator. Thereby, the drive control function 442 moves the C-arm 14 along the longitudinal direction of the rail r1 via the C-arm drive device 142 and retracts the C-arm 14 to the wall side (not shown).

[0052] After the retraction of the C-arm 14, the X-ray diagnostic apparatus 1 ends the operation.

[0053] As described above, according to the present embodiment, there are provided a base movable in the longitudinal direction of the rail, a first support arm rotatably supported by the base about a first rotation axis, a second support arm rotatably supported by the first support arm about a second rotation axis, and a C-arm. Accordingly, by controlling the movement of the base, the rotation about the first rotation axis, and the rotation about the second rotation axis, the C-arm is translated in the width direction of the rail.

[0054] Therefore, the C-arm can be translated in parallel, realizing a structure that is smaller and simpler than the X-Y stage structure. Supplementary note: As shown in FIG. 6 or FIG. 7, the C-arm can be translated in parallel. Also, a rail structure and a drive unit that are movable in the width direction of the rail r1 in the X-Y stage structure are not required. For this reason, according to the present embodiment, a structure that is smaller and simpler than the X-Y stage structure can be realized.

[0055] Note that FIG. 8 is an external view of an X-ray diagnostic apparatus of a comparative example having an X-Y stage structure. Parts corresponding to those in FIG. 2 are denoted by the same reference numerals and redundant descriptions are omitted, and mainly different parts will be described. The same applies to the following drawings and redundant descriptions are omitted. The X-ray diagnostic apparatus of the comparative example includes an X-Y stage structure having a ceiling traveling frame 14y that is movable along the longitudinal direction of the rail r1 and a base 14x that is movable within the ceiling traveling frame 14y along the width direction of the rail r1. As a result, the base 14x can be translated in parallel in the longitudinal direction and the width direction of the rail r1. The base 14a supports the upper end of the support arm 14c so as to be rotatable about the first rotation axis z1 in the vertical direction. A connection portion 14d provided at the lower end of the support arm 14c slidably supports the C-arm 14 along the arc shape of the C-arm 14, and rotates the C-arm 14 with respect to the support arm 14c by rotating about an arm main rotation axis extending parallel to the ceiling surface from this connection portion 14d. Also, the isocenter axis zS is located on the extension line of the first rotation axis z1 in the initial state of rotation by the first rotation axis z1, the arm main rotation axis, and the arm slide axis. At this time, in the horizontal plane (plan view), the isocenter axis zS overlaps the first rotation axis z1.

[0056] In such a comparative example, as described above, a large and complex X-Y stage structure is required. In contrast, according to the present embodiment, a structure that is smaller and simpler than the X-Y stage structure can be realized.

[0057] FIG. 9 is an external view of an X-ray diagnostic apparatus according to another comparative example. The X-ray diagnostic apparatus according to another comparative example is a floor-standing type, and includes a first support arm that is rotatably supported in the horizontal direction by a first rotation axis z1a from a base (not shown) disposed on the floor surface, and a second support arm that is rotatably supported in the horizontal direction by a second rotation axis z2a from the tip of the first support arm. The floor-standing type is configured to interlock such two rotation axes z1a and z2a so that the isocenter axis zS of the C-arm 14 can be linearly moved while being rotated. The direction of the linear movement may be the direction of the body axis Y of the subject P as shown in FIG. 9(a), or may be the lateral direction (X direction) of the subject P as shown in FIG. 9(b).

[0058] In such another comparative example, as described above, since the C-arm 14 cannot be translated, the C-arm 14 cannot be arranged directly beside the subject P, and X-ray imaging involving a C-arm slide operation cannot be performed. For example, in another comparative example, X-ray imaging such as rotational DSA imaging, three-dimensional DSA imaging, and three-dimensional LCI imaging cannot be performed.

[0059] On the other hand, according to the present embodiment, since the C-arm can be translated, the C-arm 14 can be arranged directly beside the subject P, and X-ray imaging involving a C-arm slide operation can be performed. Instead of the rail disposed on the ceiling, a floor rail disposed on the floor surface may be provided, and the base of the floor-standing X-ray diagnostic apparatus may be moved along the floor rail, and an X-ray diagnostic apparatus similar to the present embodiment may be realized by a configuration using the same translation control function as described above.

[0060] Further, according to the present embodiment, when the C-arm is translated along the width direction, the rotations by the first rotation axis and the second rotation axis are controlled to the same angle with each other, and the movement of the base is controlled. Thereby, the C-arm can be translated with simple control. Note that the horizontal distance between the second rotation axis z2 and the first rotation axis z1 and the horizontal distance between the second rotation axis z2 and the isocenter axis zS are not limited to being equal to each other, and may be different from each other.

[0061] Also, according to the present embodiment, when the horizontal distance between the first rotation axis and the second rotation axis is L, the same angle is θ, and the moving distance of the base is D, the movement of the base is controlled based on the relationship D = L - L cosθ. Thereby, the C-arm can be translated more simply by control. Note that the mathematical formula D = L - L cosθ may be subjected to a mathematically equivalent transformation, for example, D = L(1 - cosθ). Similarly, the horizontal distance between the second rotation axis z2 and the first rotation axis z1 and the horizontal distance between the second rotation axis z2 and the isocenter axis zS are not limited to being equal to each other, and may be different from each other. When the two horizontal distances are different from each other, the distance "L" in the formula "D = L - L cosθ" may be the horizontal distance between the second rotation axis z2 and the first rotation axis z1.

[0062] <Second Embodiment> Next, an X-ray diagnostic apparatus according to the second embodiment will be described. The second embodiment is an application example of the first embodiment, and has a configuration in which when the C-arm 14 is retracted to the wall side, the C-arm 14 can be retracted to near the wall in parallel with the wall.

[0063] Accordingly, in addition to the above-described functions, the drive control function 442 of the processing circuit 44 has a retraction control function. However, since the retraction control function can be executed independently of the above-described translation control function, the drive control function 442 of the present embodiment does not necessarily have the above-described translation control function (translation control function along the width direction of the rail r1). The retraction control function may execute the retraction control of the C-arm 14 as shown in any of the following (A) to (C) based on information stored in advance in the memory 41, for example.

[0064] (A) When the memory 41 stores retraction position information including the coordinate information of the base position, the first rotation axis z1, and the second rotation axis z2 The retraction control function moves the C-arm 14 to the wall side by controlling the base 14a, the first rotation axis z1, and the second rotation axis z2 based on the retraction position information read from the memory 41. Here, the order of controlling the base 14a, the first rotation axis z1, and the second rotation axis z2 is arbitrary. For example, after controlling the base 14a, the first rotation axis z1 and / or the second rotation axis z2 may be controlled. Further, the coordinate information of the base position may be, for example, the coordinate values in the inspection room or the value indicating the position on the rail r1. The coordinate information of the first rotation axis z1 and the second rotation axis z2 may be, for example, the coordinate values in the inspection room or the information indicating the rotation direction and rotation angle of each rotation axis.

[0065] (B) When the memory 41 stores the base position (1) After moving the base 14a to the base position read from the memory 41, the retraction control function controls the first rotation axis z1 and the second rotation axis z2 while detecting the wall or the C-arm 14 with a sensor such as a camera to move the C-arm 14 to the wall side. Here, the sensor may detect not only the wall or the C-arm 14 but also the interfering objects in the vicinity of the wall. When the sensor detects an interfering object, the retraction control function moves the C-arm 14 so as not to collide with the interfering object. The sensor can be attached to any position such as the C-arm 14, the ceiling, or the wall. The sensor is not limited to a camera and may be, for example, an ultrasonic sensor, or a camera and an ultrasonic sensor may be used in combination.

[0066] (C) When the memory 41 stores the base position (2) After moving the base 14a to the base position read from the memory 41, the retraction control function moves the C-arm 14 to the wall side according to the operation of the input interface 43 by the operator. Specifically, for example, the retraction control function may move the C-arm 14 by interlocking the first rotation axis z1 and the second rotation axis z2 in response to one input operation.

[0067] Note that in any of the above (A) to (C), the retraction control function of the present embodiment can translate the C-arm 14 as follows. That is, when the retraction control function of the drive control function 442 retracts the C-arm 14, after moving the base 14a along the longitudinal direction of the rail r1, the rotation by at least the first rotation axis z1 and the second rotation axis z2 is controlled to translate the C-arm 14. Here, the term "at least" means including the case where only the rotation by the first rotation axis z1 and the second rotation axis z2 is performed out of the movement of the base 14a and the rotation by the first rotation axis z1 and the second rotation axis z2. In this case, the C-arm 14 translates along an oblique direction between the longitudinal direction and the width direction of the rail r1. In addition, in the retraction operation to the wall, the C-arm 14 may translate in an oblique direction. That is, in the retraction operation to the wall, unlike the cases of FIGS. 6 or 7, the base 14a may be stationary.

[0068] When this retraction control function translates the C-arm 14 along the width direction of the rail r1, the rotations by the first rotation axis z1 and the second rotation axis z2 may be controlled to the same angle with each other, and the movement of the base 14a may be controlled. Here, when the horizontal distance between the first rotation axis z1 and the second rotation axis z2 is L, the same angle is θ, and the movement distance of the base 14a is D, the retraction control function may control the movement of the base 14a based on the relationship of D = L - L cos θ. In addition, the retraction control function may control the rotations by the first rotation axis z1 and the second rotation axis z2 to 90 degrees respectively. Further, the retraction control function in the drive control function 442 is an example of the retraction control means described in the claims.

[0069] Other configurations are the same as those in the first embodiment.

[0070] Next, the operation of the X-ray diagnostic apparatus configured as described above will be described with reference to the flowchart of FIG. 10 and the schematic diagrams of FIGS. 11 to 14. The following description mainly describes the operation when retracting the C-arm 14 in step ST5 described above.

[0071] Step ST5 is executed as shown in the following steps ST5-1 to ST5-4.

[0072] In step ST5-1, the processing circuit 44 of the X-ray diagnostic apparatus 1 receives a retraction instruction for the C-arm 14 in response to an operation of the input interface 43 by the operator.

[0073] In step ST5-2, the drive control function 442 of the processing circuit 44 reads the base position from the memory 41 in response to the retraction instruction, and based on this base position, controls the C-arm drive device 142 to move the base 14a to the set position along the longitudinal direction of the rail r1. As a result, the C-arm 14 moves to the set position along the rail r1. The set position is at the edge of the examination room that houses the X-ray diagnostic apparatus 1 as shown in the plan view in Fig. 11(a) and the front view in Fig. 11(b). At the set position, on the horizontal plane, the straight line CL, the longitudinal direction of the rail r1, and the wall wL are substantially parallel to each other. Also, at the set position, on the horizontal plane, the isocenter axis zS overlaps the first rotation axis z1. Note that the set position is not limited to the case where the wall wL is located on the right side of the paper surface, and the wall wL may be located on the left side of the paper surface. Similarly, the retraction operation to the vicinity of the wall described later is not limited to the case where the wall wL is located on the right side of the paper surface, and can also be executed when the wall wL is located on the left side of the paper surface.

[0074] After the completion of step ST5-2, in step ST5-3, the drive control function 442 moves the C-arm 14 in parallel by controlling the rotation by at least the first rotation axis z1 and the second rotation axis z2. The control of the rotation by the rotation axis may be control based on the retracted position information in the memory 41, may be control based on the output from a sensor (not shown), or may be interlocking control in response to one input operation. In any case, by controlling the rotation by the rotation axis, the C-arm 14 retracts to the retracted position near the wall. At the retracted position, as shown in the plan view in FIG. 12(a) and the front view in FIG. 12(b), on the horizontal plane, the straight line CL, the longitudinal direction of the rail r1, and the wall wL are substantially parallel to each other. Further, at the retracted position, on the horizontal plane, the second rotation axis z2 and the isocenter axis zS are not between the two rails r1, but are between one rail r1 and the wall wL. That is, the C-arm 14 is retracted substantially parallel to the wall wL (step ST5-4).

[0075] Incidentally, when the retraction control function moves the C-arm 14 in parallel along the width direction of the rail r1, it controls the rotations by the first rotation axis z1 and the second rotation axis z2 to the same angle θ with each other and controls the movement of the base 14a. Here, when the horizontal distance between the first rotation axis z1 and the second rotation axis z2 is L, the same angle is θ, and the movement distance of the base 14a is D1, the retraction control function controls the movement of the base 14a based on the relationship D1 = L - L cos θ. However, in this embodiment, since it is only necessary to retract the C-arm 14 to the wall side, it is not necessary to move the C-arm 14 in parallel along the width direction of the rail r1, and the C-arm 14 may be moved in parallel in a direction deviating from the width direction of the rail r1 (oblique direction). That is, when moving the C-arm 14 from the set position to the retracted position, the base 14a may be stationary. However, the base 14a may be moved. In the retraction operation of the C-arm 14, when the base 14a is moved, the movement distance of the base 14a may be D1 or may be other than D1. Further, the angle θ of the rotation by the first rotation axis z1 and the second rotation axis z2 may be set to θ = arc sin(d / L) based on d = L sin θ when the distance between the first rotation axis z1 and the straight line CL is d at the retracted position shown in FIG. 12(a).

[0076] Further, the retraction control function may control the rotations by the first rotation axis z1 and the second rotation axis z2 to 90 degrees each. In this case, as shown in the plan view in FIG. 13(a) and the front view in FIG. 13(b) respectively, the C-arm 14 is retracted to the retraction position along the wall. Alternatively, as shown in the plan view in FIG. 14(a) and the front view in FIG. 14(b) respectively, the C-arm 14 may be retracted to the retraction position along the wall. In either case, as described above, when moving the C-arm 14 from the set position to the retraction position, it is not necessary to move the base 14a. Further, when moving the base 14a, for example, the moving distance D1 of the base 14a may be set to the horizontal distance L between the first rotation axis z1 and the second rotation axis z2 (D1 = L - L cosθ = L - L cos90° = L).

[0077] After the end of step ST5-4, the X-ray diagnostic apparatus 1 ends the operation.

[0078] As described above, according to the present embodiment, when retracting the C-arm, after moving the base along the longitudinal direction of the rail, the C-arm is translated by controlling the rotations by at least the first rotation axis and the second rotation axis.

[0079] Therefore, the C-arm can be translated, and a structure smaller and simpler than the X-Y stage structure can be realized. Additionally, as shown in FIG. 11 and each of FIGS. 12 to 14, the C-arm 14 can be translated. Also, a rail structure and a drive unit that are movable in the width direction of the rail r1 in the X-Y stage structure are not required. For this reason, according to the present embodiment, a structure smaller and simpler than the X-Y stage structure can be realized. In addition to this, during retraction, the first support arm 14c1 having the first rotation axis z1 overlapping the isocenter axis zS and the second support arm 14c2 having the second rotation axis z2 at a position away from the isocenter axis zS are interlocked. As a result, as shown in each of FIGS. 12 to 14, the C-arm 14 can be retracted as close as possible parallel to the wall wL. For this reason, after retracting the C-arm 14, a large working space for the operator around the subject can be secured.

[0080] Note that Fig. 15 is a plan view and a front view of a comparative example having an X-Y stage structure, and shows the retraction operation of the C-arm in the X-ray diagnostic apparatus of the comparative example shown in Fig. 8. The upper half (a) of Fig. 15 is a plan view, and the lower half (b) of Fig. 15 is a front view.

[0081] According to the X-Y stage structure of the comparative example, when retracting the C-arm 14, as shown from the left side to the right side of Fig. 15, the base 14x is moved along the width direction of the rail r1 within the ceiling traveling frame 14y, and the support arm 14c is rotated about the first rotation axis z1 of the base 14x. In Fig. 15, "D1a" indicates the moving distance of the base 14x along the width direction of the rail r1. "CLa" indicates a straight line connecting the first rotation axis z1 and the arm main rotation axis of the connection part 14d on the horizontal plane. "L" indicates the horizontal distance of the straight line CLa.

[0082] At this time, in the comparative example, as shown on the right side of Fig. 15(a), the first rotation axis z1 and the isocenter axis zS are located between the two rails r1, and the straight line CLa is located obliquely with respect to the wall wL. That is, in the comparative example, because of the structure where there is always an isocenter on the extension line of the first rotation axis z1, the C-arm 14 cannot be translated parallel to the outside of the two rails r1, and the C-arm 14 cannot be retracted closer to the wall wL than the first rotation axis z1.

[0083] On the other hand, according to the present embodiment, the C-arm can be translated parallel to the outside of the two rails r1, and a structure smaller and simpler than the X-Y stage structure can be realized.

[0084] Further, according to the present embodiment, when translating the C-arm parallel to the width direction, the rotations by the first rotation axis and the second rotation axis are controlled to the same angle with each other, and the movement of the base is controlled. Thereby, the C-arm can be translated with simple control. Note that the horizontal distance between the second rotation axis z2 and the first rotation axis z1 and the horizontal distance between the second rotation axis z2 and the isocenter axis zS are not limited to being equal to each other, and may be different from each other.

[0085] Further, according to the present embodiment, when the horizontal distance between the first rotation axis and the second rotation axis is L, the same angle is θ, and the moving distance of the base is D, the movement of the base is controlled based on the relationship D = L - L cos θ. Thereby, the C-arm can be translated with simpler control. Note that the mathematical formula D = L - L cos θ may be subjected to a mathematically equivalent transformation such as D = L(1 - cos θ). Similarly, the horizontal distance between the second rotation axis z2 and the first rotation axis z1 and the horizontal distance between the second rotation axis z2 and the isocenter axis zS are not limited to being equal to each other, and may be different from each other. When the two horizontal distances are different from each other, the distance "L" in the formula "D = L - L cos θ" may be the horizontal distance between the second rotation axis z2 and the first rotation axis z1.

[0086] Also, according to the present embodiment, the rotations by the first rotation axis and the second rotation axis are each controlled to be 90 degrees. In this case, the C-arm can be translated with even simpler control. In addition, a wide working space can be quickly secured.

[0087] <Third Embodiment> Next, an X-ray diagnostic apparatus according to the third embodiment will be described. The third embodiment is a modification of the second embodiment, and has a configuration in which the rotations by at least the first rotation axis z1 and the second rotation axis z2 are controlled with the orientation of the C-arm 14 after retraction as the target.

[0088] Accordingly, when the retraction control function retracts the C-arm 14, at least by the rotations of the first rotation axis z1 and the second rotation axis z2, the longitudinal direction of the first support arm 14c1 intersects the longitudinal direction of the rail r1, and the front direction of the C-arm 14 is parallel or perpendicular to the longitudinal direction of the rail r1, the C-arm 14 is retracted. Here, the term "at least" has the meaning described above. Note that the retraction control function does not necessarily have to retract the C-arm 14 to the wall side. Other configurations are the same as those of the second embodiment. According to the configuration as described above, the retraction control function retracts the C-arm 14 such that, by rotation about at least the first rotation axis z1 and the second rotation axis z2, the longitudinal direction of the first support arm 14c1 intersects the longitudinal direction of the rail r1, and the front direction of the C-arm 14 is parallel or perpendicular to the longitudinal direction of the rail r1.

[0089] Here, when the C-arm 14 is retracted such that the front direction of the C-arm 14 is parallel to the longitudinal direction of the rail r1, at the retracted position, as shown in any one of FIGS. 12 to 14 described above, the C-arm 14 is positioned in the vicinity of the wall wL.

[0090] On the other hand, when the C-arm 14 is retracted such that the front direction of the C-arm 14 is perpendicular to the longitudinal direction of the rail r1, at the retracted position, as shown in any one of FIGS. 16 to 18, on the horizontal plane, the straight line CL and the longitudinal direction of the rail r1 are substantially perpendicular to each other. Also, on the horizontal plane, the straight line CL and the wall wL are substantially parallel to each other. FIGS. 16 to 18 are a plan view and a front view showing the case where the rail r1 is rotated 90 degrees in the horizontal direction as compared with FIGS. 12 to 14, respectively.

[0091] Therefore, in any case, according to the third embodiment, the same effects as those of the second embodiment can be obtained.

[0092] <Fourth Embodiment> FIG. 19 is a block diagram showing the configuration of the angio CT apparatus according to the fourth embodiment, and FIGS. 20 and 21 are an external view and a plan view of the angio CT apparatus, respectively.

[0093] The fourth embodiment has a configuration in which the X-ray diagnostic apparatus 1 according to any one of the first to third embodiments is applied to an angiography CT apparatus. As shown in FIG. 19, this angiography CT apparatus 100 includes the above-described X-ray diagnostic apparatus 1, a CT (Computed Tomography) gantry 50, and a console apparatus 70. Note that, among the angiography CT apparatus 100, the angiography apparatus corresponds to the above-described X-ray diagnostic apparatus 1. Among the angiography CT apparatus 100, the CT apparatus corresponds to the bed apparatus 30, the CT gantry 50, and the console apparatus 70. The bed apparatus 30 is commonly used for the angiography apparatus and the CT apparatus. Note that the console apparatuses 40 and 70 may be integrated (integrated).

[0094] Here, as described above, the X-ray diagnostic apparatus 1 includes an imaging apparatus 10, a bed apparatus 30, and a console apparatus 40.

[0095] As shown in FIGS. 20 and 21, the imaging apparatus 10 includes a base 14a, a first support arm 14c1, a second support arm 14c2, and a C arm 14, as described above.

[0096] The base 14a is supported by a rail r1 disposed on the ceiling and is movable in the longitudinal direction of the rail r1. Note that the rail r1 may be referred to as a “ceiling rail” or a “first rail”. The first support arm 14c1 is supported by the base 14a so as to be rotatable about a first vertical rotation axis z1. The second support arm 14c2 is supported by the first support arm 14c1 so as to be rotatable about a second vertical rotation axis z2. The C arm 14 is supported by the second support arm 14c2. Other configurations of the imaging apparatus 10 are as described above.

[0097] The bed apparatus 30 and the console apparatus 40 are capable of communicating with the console apparatus 70. Other configurations of the bed apparatus 30 and the console apparatus 40 are the same as described above. For example, the drive control function 442 of the processing circuit 44 of the console apparatus 40 includes a translation control function that controls the movement of the base 14a, the rotation about the first rotation axis z1, and the rotation about the second rotation axis z2 to translate the C-arm 14 along the width direction of the rail r1, as described above. Not limited thereto, the drive control function 442 can execute a desired control function among all the translation control functions and the retraction control functions described above.

[0098] On the other hand, the CT gantry 50 is a rail r2 disposed on the floor surface and is movable on the rail r2 having a longitudinal direction orthogonal to the longitudinal direction of the rail r1 disposed on the ceiling. Note that the rail r2 may be referred to as a "floor rail" or a "second rail". The longitudinal direction of the rail r2 is parallel to the direction of the body axis Y of the subject P and the longitudinal direction of the top plate 33.

[0099] Returning to FIG. 20, the CT gantry 50 includes an X-ray tube 51, an X-ray detector 52, a rotating frame 53, an X-ray high voltage device 54, a CT control device 55, a wedge 56, a collimator 57, and a DAS 58.

[0100] The X-ray tube 51 generates X-rays. Specifically, the X-ray tube 51 includes a vacuum tube that holds a cathode that generates thermoelectrons and an anode that receives the thermoelectrons flying from the cathode and generates X-rays. The X-ray tube 51 is connected to the X-ray high voltage device 54 via a high voltage cable. A tube voltage is applied between the cathode and the anode by the X-ray high voltage device 54. When the tube voltage is applied, thermoelectrons fly from the cathode toward the anode. When thermoelectrons fly from the cathode toward the anode, a tube current flows. By applying a high voltage from the X-ray high voltage device 54 and supplying a filament current, thermoelectrons fly from the cathode toward the anode, and when the thermoelectrons collide with the anode, X-rays are generated.

[0101] The X-ray detector 52 detects the X-rays generated from the X-ray tube 51 that have passed through the subject P, and outputs an electrical signal corresponding to the detected X-ray dose to the DAS 58. The X-ray detector 52 has a structure in which a plurality of X-ray detection element arrays, in which a plurality of X-ray detection elements are arranged in the channel direction, are arranged in a plurality in the slice direction (column direction, row direction). The X-ray detector 52 is, for example, an indirect conversion type detector having a grid, a scintillator array, and an optical sensor array. The scintillator array has a plurality of scintillators. The scintillator outputs light in an amount corresponding to the incident X-ray dose. The grid is disposed on the X-ray incident surface side of the scintillator array and has an X-ray shielding plate that absorbs scattered X-rays. The optical sensor array converts the light amount of the light from the scintillator into an electrical signal. As the optical sensor, for example, a photomultiplier tube is used. Note that the X-ray detector 52 may be a direct conversion type detector (semiconductor detector) having a semiconductor element that converts incident X-rays into an electrical signal.

[0102] The rotary frame 53 is an annular frame that rotatably supports the X-ray tube 51 and the X-ray detector 52 around the rotation axis Y that coincides with the body axis Y. Specifically, the rotary frame 53 supports the X-ray tube 51 and the X-ray detector 52 so as to face each other. The rotary frame 53 is rotatably supported around the rotation axis Y by a fixed frame (not shown). The CT control device 55 rotates the rotary frame 53 around the rotation axis Y, thereby rotating the X-ray tube 51 and the X-ray detector 52 around the rotation axis Y. The rotary frame 53 rotates at a constant angular velocity around the rotation axis Y by receiving power from the drive mechanism of the CT control device 55. An image field of view (FOV) is set in the opening of the rotary frame 53.

[0103] The X-ray high voltage device 54 has electric circuits such as a transformer and a rectifier, and includes a high voltage generator that generates the high voltage applied to the X-ray tube 51 and the filament current supplied to the X-ray tube 51, and an X-ray control device that controls the output voltage according to the X-ray irradiated by the X-ray tube 51. The high voltage generator may be of a transformer type or an inverter type. The X-ray high voltage device 54 may be provided on the rotating frame 53 in the CT gantry 50, or may be provided on a fixed frame (not shown) in the CT gantry 50.

[0104] The wedge 56 adjusts the dose of X-rays irradiated to the subject P. Specifically, the wedge 56 attenuates the X-rays so that the dose of X-rays irradiated from the X-ray tube 51 to the subject P has a predetermined distribution. For example, as the wedge 56, a metal plate such as aluminum like a wedge filter or a bow-tie filter is used.

[0105] The collimator 57 limits the irradiation range of the X-rays that have passed through the wedge 56. The collimator 57 slidably supports a plurality of lead plates that shield the X-rays, and adjusts the form of the slit formed by the plurality of lead plates.

[0106] The DAS 58 (Data Acquisition System) reads out an electric signal corresponding to the dose of X-rays detected by the X-ray detector 52 from the X-ray detector 52, amplifies the read electric signal with a variable amplification factor, and integrates the electric signal over the view period to collect CT raw data having a digital value corresponding to the dose of X-rays over the view period. The DAS 58 is realized, for example, by an ASIC equipped with circuit elements capable of generating CT raw data. The CT raw data is transmitted to the console device 70 via a non-contact data transmission device or the like.

[0107] The CT control device 55 controls the X-ray high voltage device 54 and the DAS 58 to perform X-ray CT imaging according to the imaging control function 733 of the processing circuit 73 of the console device 70. The CT control device 55 has a processing circuit including a CPU or the like, and a drive mechanism such as a motor and an actuator. The processing circuit has, as hardware resources, a processor such as a CPU or an MPU, and a memory such as a ROM and a RAM. Further, the CT control device 55 may be realized by an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), a CPLD (Complex Programmable Logic Device), or an SPLD (Simple Programmable Logic Device).

[0108] Note that the CT gantry 50 has various types such as a Rotate / Rotate-Type (third-generation CT) in which the X-ray generation unit and the X-ray detection unit rotate integrally around the subject, and a Stationary / Rotate-Type (fourth-generation CT) in which a large number of X-ray detection elements arranged in a ring are fixed and only the X-ray generation unit rotates around the subject. Any type can be applied.

[0109] The console device 70 has a communication interface 71, a CT data memory 72, a processing circuit 73, a display 74, a memory 75, and an input interface 76. For example, data communication among the communication interface 71, the CT data memory 72, the processing circuit 73, the display 74, the memory 75, and the input interface 76 is performed via a bus.

[0110] The communication interface 71 is a circuit for communicating with the console device 40 by wire, wirelessly, or both. Although not shown, the console device 40 also includes a communication interface, which is a circuit for communicating with the console device 70.

[0111] The CT data memory 72 is a storage device that stores the raw CT data transmitted from the CT gantry 50. The CT data memory 72 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit memory device.

[0112] The processing circuit 73 has, as hardware resources, a processor such as a CPU or an MPU, a GPU (Graphics Processing Unit), and a memory such as a ROM and a RAM. The processing circuit 73 realizes a reconstruction function 731, an image processing function 732, an imaging control function 733, and a display control function 734 by executing various programs read from the memory. Note that the reconstruction function 731, the image processing function 732, the imaging control function 733, and the display control function 734 may be implemented by the processing circuit 73 on one substrate, or may be distributed and implemented by the processing circuits 73 on a plurality of substrates.

[0113] In the reconstruction function 731, the processing circuit 73 reconstructs a CT image that represents the spatial distribution of CT values regarding the subject P based on the raw CT data transmitted from the CT gantry 50. As the image reconstruction algorithm, an existing algorithm such as the FBP (filtered back projection) method or the successive approximation reconstruction method may be used. Also, the processing circuit 73 can generate a positioning image regarding CT based on the raw CT data.

[0114] In the image processing function 732, the processing circuit 73 performs various image processes on the CT image reconstructed by the reconstruction function 731. For example, the processing circuit 73 performs three-dimensional image processes such as volume rendering, surface volume rendering, pixel value projection processing, MPR (Multi-Planer Reconstruction) processing, and CPR (Curved MPR) processing on the CT image to generate a display image.

[0115] In the imaging control function 733, the processing circuit 73 synchronously controls the CT gantry 50 and the bed device 30 to perform CT imaging. Further, the processing circuit 73 is capable of executing a positioning scan by the CT gantry 50 (hereinafter referred to as a CT positioning scan). For the CT positioning scan, the processing circuit 73 synchronously controls the CT gantry 50 and the bed device 30.

[0116] In the display control function 734, the processing circuit 73 displays various information on the display 74. For example, the processing circuit 73 displays the CT image reconstructed by the reconstruction function 731 on the display 74.

[0117] The display 74 receives the control of the processing circuit 73 in the display control function 734 and displays various information. As the display 74, 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.

[0118] The memory 75 is a storage device such as an HDD, an SSD, or an integrated circuit storage device that stores various information. Further, the memory 75 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, or a flash memory.

[0119] The input interface 76 inputs various commands from the user. Specifically, the input interface 76 is connected to an input device. As the input device, a keyboard, a mouse, a trackball, a joystick, various switches, etc. can be used. The input interface 76 supplies the output signal from the input device to the processing circuit 73 via the bus.

[0120] Next, the operation of the angiography CT apparatus configured as described above will be described.

[0121] In the angiography CT apparatus 100, the C-arm 14 is retracted along the rail r1, and the CT gantry 50 is set at the imaging position along the rail r2, whereby the CT apparatus can be used. Further, by retracting the CT gantry 50 along the rail r2 and setting the C-arm 14 at the imaging position along the rail r1, the X-ray diagnostic apparatus 1 as an angiography apparatus can be used.

[0122] Here, when the X-ray diagnostic apparatus 1 can be used, the X-ray diagnostic apparatus 1 can operate in the same manner as the steps ST1 to ST5 described above. At this time, the X-ray diagnostic apparatus 1 can translate the C-arm 14 along the width direction of the rail r1 by controlling, for example, the movement of the base 14a, the rotation by the first rotation axis z1, and the rotation by the second rotation axis z2, as described above.

[0123] Further, the X-ray diagnostic apparatus 1 can operate in the same manner as the steps ST5-1 to ST5-4 described above. When retracting the C-arm 14, the X-ray diagnostic apparatus 1 can translate the C-arm 14 by controlling, for example, the movement of the base 14a along the longitudinal direction of the rail r1 and then controlling the rotation by at least the first rotation axis z1 and the second rotation axis z2, as described above.

[0124] As described above, according to the present embodiment, after moving the CT gantry along the second rail disposed on the floor surface, the C-arm is translated along the width direction of the first rail by controlling the movement of the base, the rotation by the first rotation axis, and the rotation by the second rotation axis. Thereby, in the angiography CT apparatus, the same effect as in the first embodiment can be obtained.

[0125] Further, when retracting the C-arm, after moving the base along the longitudinal direction of the first rail, the C-arm is translated by controlling the rotation by at least the first rotation axis and the second rotation axis. Thereby, in the angiography CT apparatus, the same effect as in the second embodiment can be obtained.

[0126] According to at least one embodiment described above, a base movable in the longitudinal direction of a rail, a first support arm rotatably supported by the base about a first rotation axis, a second support arm rotatably supported by the first support arm about a second rotation axis, and a C-arm are provided. Accordingly, by controlling the movement of the base, the rotation about the first rotation axis, and the rotation about the second rotation axis, the C-arm is translated along the width direction of the rail.

[0127] Therefore, the C-arm can be translated, and a structure smaller and simpler than an X-Y stage structure can be realized.

[0128] The term "processor" used in the above description means, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or a circuit such as an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (e.g., a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), and a Field Programmable Gate Array (FPGA)). The processor realizes its function by reading and executing a program stored in a storage circuit. Instead of storing the program in the storage circuit, the program may be directly incorporated into the circuit of the processor. In this case, the processor realizes its function by reading and executing the program incorporated into the circuit. Each processor of the present embodiment is not limited to being configured as a single circuit for each processor, and a plurality of independent circuits may be combined to be configured as one processor to realize its function. Further, a plurality of components in FIG. 1 or FIG. 16 may be integrated into one processor to realize its function.

[0129] Although some 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 gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, as well as in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0130] 1…X-ray diagnostic apparatus, 10…imaging apparatus, 11…high voltage generator, 12…X-ray generation unit, 13, 52…X-ray detector, 14…C-arm, 14a…base, 14b1, 14b2…fulcrum, 14c1…first support arm, 14c2…second support arm, 14d…connection part, 141…state detector, 142…C-arm drive device, 30…bed device, 31…base, 32…bed drive device, 33…top plate, 34…support frame, 40, 70…console device, 41, 75…memory, 42, 74…display, 43, 76…input interface, 44, 73…processing circuit, 441…system control function, 442…drive control function, 443…X-ray control function, 444, 732…image processing function, 445, 734…display control function, 50…CT gantry, 51…X-ray tube, 53…rotating frame, 54…X-ray high voltage device, 55…CT control device, 56…wedge, 57…collimator, 58…DAS, 71…communication interface, 72…CT data memory, 731…reconstruction function, 733…imaging control function, 100…angiography CT apparatus, CL…straight line, IS…isocenter, Rc…arm main rotation axis, r1, r2…rail, wL…wall, z1…first rotation axis, z2…second rotation axis, zS…isocenter axis.

Claims

1. A base supported by a rail disposed on the ceiling and movable in the longitudinal direction of the rail, a first support arm supported by the base rotatably about a first vertical rotation axis, and a second support arm supported by the first support arm rotatably about a second vertical rotation axis, a C-arm supported by the second support arm, a translation control means for translating the C-arm along the width direction of the rail by controlling the movement of the base, the rotation about the first rotation axis, and the rotation about the second rotation axis, an X-ray diagnostic apparatus comprising the same.

2. The X-ray diagnostic apparatus according to claim 1, wherein when the translation control means translates the C-arm along the width direction, the rotations about the first rotation axis and the second rotation axis are controlled to the same angle with each other, and the movement of the base is controlled.

3. When the horizontal distance between the first rotation axis and the second rotation axis is L, the same angle is θ, and the movement distance of the base is D, the translation control means controls the movement of the base based on the relationship D = L - L cosθ. The X-ray diagnostic apparatus according to claim 2.

4. When retracting the C-arm, after moving the base along the longitudinal direction of the rail, a retraction control means for translating the C-arm by controlling at least the rotations about the first rotation axis and the second rotation axis, The X-ray diagnostic apparatus according to any one of claims 1 to 3, further comprising the same.

5. The X-ray diagnostic apparatus according to claim 4, wherein when the retraction control means translates the C-arm along the width direction, the rotations about the first rotation axis and the second rotation axis are controlled to the same angle with each other, and the movement of the base is controlled.

6. When the horizontal distance between the first rotation axis and the second rotation axis is L, the same angle is θ, and the movement distance of the base is D, the retraction control means controls the movement of the base based on the relationship D = L - L cosθ. The X-ray diagnostic apparatus according to claim 5.

7. The X-ray diagnostic apparatus according to claim 5 or 6, wherein the retraction control means controls the rotations about the first rotation axis and the second rotation axis to 90 degrees respectively.

8. When retracting the C-arm, at least by rotation about the first rotation axis and the second rotation axis, the longitudinal direction of the first support arm intersects the longitudinal direction of the rail, and the front direction of the C-arm is parallel or perpendicular to the longitudinal direction of the rail, a retraction control means for retracting the C-arm, The X-ray diagnostic apparatus according to any one of claims 1 to 3, further comprising.

9. A base supported by a rail disposed on the ceiling and movable in the longitudinal direction of the rail, A first support arm supported by the base so as to be rotatable about a first rotation axis in the vertical direction, and a second support arm supported by the first support arm so as to be rotatable about a second rotation axis in the vertical direction, A C-arm supported by the second support arm, When retracting the C-arm, after moving the base along the longitudinal direction of the rail, a retraction control means for translating the C-arm by controlling rotation about at least the first rotation axis and the second rotation axis, An X-ray diagnostic apparatus comprising.

10. A base supported by a rail disposed on the ceiling and movable in the longitudinal direction of the rail, A first support arm supported by the base so as to be rotatable about a first rotation axis in the vertical direction, and a second support arm supported by the first support arm so as to be rotatable about a second rotation axis in the vertical direction, A C-arm supported by the second support arm, When retracting the C-arm, at least by rotation about the first rotation axis and the second rotation axis, the longitudinal direction of the first support arm intersects the longitudinal direction of the rail, and the front direction of the C-arm is parallel or perpendicular to the longitudinal direction of the rail, a retraction control means for retracting the C-arm, An X-ray diagnostic apparatus comprising.

11. A base supported by a first rail disposed on the ceiling and movable in the longitudinal direction of the first rail, A first support arm supported by the base so as to be rotatable about a first rotation axis in the vertical direction, and a second support arm supported by the first support arm so as to be rotatable about a second rotation axis in the vertical direction, A C-arm supported by the second support arm, A translation control means for translating the C-arm along the width direction of the first rail by controlling the movement of the base, the rotation about the first rotation axis, and the rotation about the second rotation axis, A second rail disposed on the bed surface, and a CT gantry movable on the second rail having a longitudinal direction orthogonal to the longitudinal direction of the first rail. An angiography CT apparatus comprising the same.

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