JPH1057367A - Ct apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve throughput of a CT apparatus by enlarging the operation area of an X-ray beam and increasing collection capacity of detection signals. SOLUTION: The X-ray CT apparatus is constructed to reconstruct an X-ray tomographic image of an object body M based on X-ray detection signals output from a radial ray detector 2 in proportion to the radiation of X-ray beam FB by an X-ray tube 1. This time, the radial ray detector 2 is composed by putting in arch the one dimensional radial ray detecting arrays 3 having linearly located radiation detecting elements. In total, the apparatus is made to gain a number of X-ray detection signals on a sliced face by one round scanning by being equipped with two dimensionally located radiation detecting elements.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray CT apparatus for capturing a tomographic image of an object by rotating an X-ray tube and an X-ray detector around the object, and more particularly to an X-ray tube. And a structure of an X-ray detector suitable for so-called multi-slice imaging in which a plurality of tomographic images are obtained by one rotation of the X-ray detector.

[0002]

2. Description of the Related Art In a conventional X-ray CT apparatus, as shown in FIG. 10, an X-ray tube 91 for emitting an X-ray beam FB and an X-ray detector 92 are opposed to each other with a subject (patient) M interposed therebetween. It is provided in the form of arrangement. The X-ray tube 91 and the X-ray detector 92 are, for example, indicated by an arrow R around the body axis (rotation axis Z) of the subject M while maintaining the opposed arrangement of the X-ray tube 91 and the X-ray detector 92. The X-ray beam is emitted from the X-ray tube 91 while being rotated in the direction. An X-ray tomographic image of the subject M is reconstructed by performing data processing on an X-ray detection signal output from the X-ray detector 92 in association with the X-ray beam irradiation on the subject M.

If the X-ray detector 92 has a group of radiation detecting elements arranged in a line in the rotation direction, the X-ray tube 91 and the X-ray
The X-ray detection signal of one slice plane (one cross section) is collected by one rotation (or half rotation) of the line detector 92. When obtaining tomographic images of many slice planes, the X-ray tube 91, the X-ray detector 92, and the subject M are relatively intermittently moved in the direction of the rotation axis Z, and the same as above at each movement position. Processing is performed.

A conventional X-ray CT apparatus includes an X-ray tube 9.
1 and a number of slices perpendicular to the body axis of the subject M while performing so-called spiral scanning in which the subject M is continuously moved in a direction parallel to the rotation axis Z while rotating the X-ray detector 92. There is also one that collects and stores an X-ray detection signal of a surface to reconstruct a three-dimensional X-ray tomographic image.

[0005] Further, the radiation detecting element group is moved in the rotational direction by two.
There is a multi-slice type X-ray CT apparatus including X-ray detectors 92 arranged in rows. When the radiation detection elements are arranged in one row, only one X-ray detection signal for one slice plane can be obtained by one rotation of the X-ray detection operation, and only a part of the fan-shaped X-ray beam is used. is there. However, when the radiation detection element group is arranged in two rows, the X-ray detection operation for one slice can simultaneously obtain X-ray detection signals by one rotation of the X-ray detection operation, so that the capability of collecting the detection signals increases and the X-ray beam Use range is also doubled.

[0006]

However, the above-mentioned conventional X-ray CT apparatus has not yet been able to say that the ability to collect the detection signal and the use of the X-ray beam are sufficient. There is a problem in that it is extremely difficult to increase the size and the range of use of the X-ray beam. If the number of rows of radiation detection elements arranged in the direction of the rotation axis Z can be increased, 1
By increasing the number of slice planes capable of collecting X-ray detection signals by rotating X-ray detection operation, the collection capability can be increased, and the X-ray beam incident area can be increased to expand the use range of the X-ray beam. However, it is difficult to increase the number of arranged rows of the radiation detecting element group as described below.

A conventionally proposed X-ray detector 92 for multi-slice imaging is, as shown in FIG. 11, a radiation detecting element 96 comprising a scintillator 94 and a light detecting element 95.
As shown in FIG. 10, a plurality of two-dimensional radiation detection arrays 93, which are installed adjacent to each other in two rows, are arranged in a circular arc shape and arranged so as to form a part of a polygon. Have been. In the example of FIG. 10, a plurality of two-dimensional radiation detection arrays 93 are arranged in an arc shape such that the long sides of the rectangular two-dimensional radiation detection array 93 shown in FIG. 11 are adjacent. The light detection element 95 of each radiation detection element 96
Are integrated on a semiconductor substrate 98 die-bonded to a base substrate 97. After the X-ray detection signal from each light detection element 95 is taken out from the wiring 99 formed on the semiconductor substrate 98,
An amplifier 1 provided at the subsequent stage for each radiation detection element 96
01.

In the two-dimensional radiation detecting array 93, the radiation detecting elements 96 are sequentially increased in the direction of the rotation axis Z (in FIG. 11, along the long side of the base substrate 97). Increases the number of arrays. However, when the radiation detecting element 96 is added in a direction parallel to the rotation axis Z, the wiring for extracting the X-ray detection signal from the light detecting element 95 of the radiation detecting element 96 located in the middle to the outside is provided by a semiconductor substrate. Photodetectors 95 adjacent on 98
Therefore, the area of the light receiving surface of the photodetector 95 on the semiconductor substrate 98 becomes smaller accordingly. As a result, the signal-to-noise ratio (S / N) of the X-ray detection signal decreases, and the image quality deteriorates.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and without increasing the signal-to-noise ratio of an X-ray detection signal, increases the number of radiation detecting elements of an X-ray detector. It is an object to provide an X-ray CT apparatus suitable for imaging.

[0010]

In order to achieve the above object, the present invention has the following arrangement. That is, the invention according to claim 1 is characterized in that an X-ray generation unit and an X-ray detection unit are arranged to face each other with a subject interposed therebetween, and the X-ray generation unit emits an X-ray beam to the two units. In the X-ray CT apparatus for reconstructing an X-ray tomographic image of a subject by performing data processing on an X-ray detection signal output from the X-ray detection means at this time, , Composed of a large number of one-dimensional radiation detection arrays in which radiation detection elements in which a scintillator and a light detection element are combined are arranged in a line, and each one-dimensional radiation detection array is a line-of-line radiation detection element The arrangement of the groups is arranged so as to be substantially parallel to the axis of rotation of the X-ray generation means and the X-ray detection means, and the arrangement of the one-dimensional radiation detection arrays is arranged in an arc shape. As a whole Line detecting element group are arranged two-dimensionally.

According to a second aspect of the present invention, in the X-ray CT apparatus according to the first aspect, each one-dimensional radiation detection array includes:
Each of the radiation detection element groups is configured to be read and scanned, so that the X-ray detection signals are sequentially read,
And X read out by scanning a group of radiation detecting elements.
The line detection signal is configured to be transferred to a common amplifier.

According to a third aspect of the present invention, in the X-ray CT apparatus according to the second aspect, at the time of read-out scanning of the X-ray detection signal, the radiations arranged in a line in the circumferential direction in relation to the one-dimensional radiation detection array. The detection element group is configured to simultaneously read out the X-ray detection signal.

[0013]

The operation of the X-ray CT apparatus according to the present invention is as follows. In the X-ray CT apparatus according to the first aspect of the present invention, a large number of one-dimensional radiation detection arrays in which radiation detection elements each formed by combining a scintillator and a light detection element are arranged in a line are arranged in an arc shape. Thus, the radiation detection element group is two-dimensionally arranged as a whole. Therefore, in relation to the one-dimensional radiation detection arrays arranged in parallel, the radiation detection element group arranged in a line in an arc shape collects X-ray detection signals for one slice plane. If the one-dimensional radiation detection array has N radiation detection elements arranged in a line, the X-ray detection means constituted by arranging the one-dimensional radiation detection arrays in parallel can perform a one-point imaging operation. Thus, X-ray detection signals for N slice planes can be collected.

Further, since the one-dimensional radiation detection array constituting the X-ray detection means has a configuration in which radiation detection element groups are arranged in a line, wiring for extracting an X-ray detection signal from the radiation detection element is, for example, each wiring. If it is derived from the side of the light detecting element, the light receiving area of the light detecting element will not be reduced.

In the X-ray CT apparatus according to the second aspect, the X-ray detection signals obtained by the irradiation of the X-ray beam by the read-out scanning in each one-dimensional radiation detection array are arranged in one line in the radiation detection element group in each array. Are sequentially read out from each radiation detecting element in accordance with the arrangement of. The sequentially read X-ray detection signals are appropriately collected after being amplified by a common amplifier.
It is memorized. That is, one amplifier for amplifying the X-ray detection signal output from each radiation detection element is not necessary for each radiation detection element, and one amplifier is used for a plurality of radiation detection elements sharing the same amplifier. I just need it.

In the X-ray CT apparatus according to the third aspect, at the time of read-out scanning of the X-ray detection signal, the radiation detection element groups arranged in a line in the circumferential direction due to the relationship between the one-dimensional radiation detection arrays are used for the X-ray detection signal. Reading is performed at the same timing, and transfer of each X-ray detection signal to the amplifier corresponding to each element is performed simultaneously. Due to the relationship between the one-dimensional radiation detection arrays, the radiation detection elements arranged in a line in the circumferential direction output an X-ray detection signal for one slice plane. That is, the X-ray detection signals for one slice plane are collected simultaneously.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the X-ray CT apparatus according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram illustrating a main configuration of the X-ray CT apparatus according to the embodiment.

As shown in FIG. 1, the X-ray CT apparatus according to the embodiment includes an X-ray tube (X-ray generating means) 1 for irradiating an X-ray beam FB in a fan shape, and a large number of one-dimensional radiation detection arrays 3. X-ray detectors 2 are arranged in an arc shape, and are arranged opposite to each other with a subject M placed on a top plate 4 interposed therebetween. The X-ray tube 1 and the X-ray detector 2 are rotated around the subject M while maintaining the opposed arrangement state, and the X-ray tube 1, the X-ray detector 2 and the subject M are rotated as necessary. Is provided with a moving mechanism 5 for horizontally moving at least one of them (normally only the subject M) in a direction parallel to the rotation axis Z.

The moving mechanism 5 is configured to rotate the X-ray tube 1 and the X-ray detector 2 integrally around a rotation axis Z, and to horizontally move the top 4 in the body axis direction of the subject M. X to the subject M
The relative movement trajectory of the X-ray tube 1 and the X-ray detector 2 is shown in FIG.
X-ray tomography by so-called spiral scanning, which is indicated by the spiral U of FIG. The control of the moving mechanism 5 is performed via the operation control unit 6.

In the X-ray CT apparatus of the embodiment, the high-voltage controller 7
X-ray from the X-ray tube 1 in a fan shape
The line beam FB is emitted to the subject M. The X-ray beam FB is emitted in a form corresponding to the X-ray beam shaping collimator 8 provided on the front surface of the X-ray tube 1. Then, the transmitted X-rays from the subject M are incident on the X-ray detector 2 via the collimator 9 and detected. The scattered X-rays that cause noise are cut off by the collimator 9 on the front surface of the X-ray detector 2 and only necessary transmitted X-rays enter the X-ray detector 2.

A DAS (data acquisition system unit) 9 of the embodiment apparatus collects the X-ray detection signal from the X-ray detector 2 while amplifying it with an amplifier 10. The collected X-ray detection signals are stored in the X-ray detection signal memory unit 11.

In this way, when the collection and storage of the X-ray detection signal is completed, the data processing unit 12 subjects the X-ray detection signal read from the X-ray detection signal memory unit 11 to data processing by the Fourier transform method, and The X-ray tomographic image of the sample is reconstructed, and finally the X-ray tomographic image is displayed on the screen of the monitor 13.

Next, the X-ray detector 2, which is a characteristic configuration of the X-ray CT apparatus of the present invention, will be specifically described with reference to the drawings. 2 and 3 are diagrams showing the arrangement of the one-dimensional radiation detection array 3 in the X-ray detector 2, FIG. 4 is a diagram showing the detailed configuration of the one-dimensional radiation detection array 3, and FIG. 3 is an equivalent circuit diagram of FIG.

As shown in FIG. 2, the X-ray detector 2 is configured by arranging a one-dimensional radiation detecting array 3 having a group of radiation detecting elements 21 arranged in a line in parallel. The group of radiation detection elements 21 of each one-dimensional radiation detection array 3 is arranged so that the arrangement thereof is substantially parallel to the rotation axis Z. Further, the arrangement of the one-dimensional radiation detection arrays 3 is arranged in an arc shape as shown in FIG. The arc C is a part of a circle drawn around the focal point of the X-ray tube 1, and the distance between each radiation detection element 21 and the focal point of the X-ray tube 1 is all equal.

As shown in FIG. 2, the plurality of one-dimensional radiation detection arrays 3 are installed in the direction parallel to the rotation axis Z such that the radiation detection elements 21 are arranged in a line along the arc C. Are arranged, and the radiation detecting elements 21 are arranged two-dimensionally as a whole. That is, the two-dimensionally arranged radiation detecting elements 21 shown in FIG. 2 include vertical columns A1, A2,..., AN and horizontal (arc-shaped) columns a1, a
2, ..., an. Horizontal rows a1, a2
, An correspond to n slice planes perpendicular to the rotation axis Z, respectively. Therefore, X-ray detection signals of n slice planes can be simultaneously obtained by one X-ray detection operation in which the X-ray tube 1 and the X-ray detector 2 make one rotation (or half a rotation).

The radiation detecting element 21 has, for example, a width (length of the element along an arc) of about 1 mm and a length (length along the axis of rotation) of about 2 mm. Further, the number N of elements in the horizontal direction is, for example, about several hundreds to about 1,000, and the number n of elements in the vertical direction is, for example, about 30 to 100, but is not limited thereto. Note that FIG.
Although the radiation detection elements 21 are drawn apart for convenience of drawing, it is preferable that the gap between the elements 21 be as narrow as possible.

The configuration of each one-dimensional radiation detection array 3 is as follows. The one-dimensional radiation detection array 3 is shown in FIG.
As shown in the sectional view of (b), the radiation detecting element 21 formed by combining the scintillator 23 and the light detecting element 24
FIG. 4A shows a read / scan IC (integrated circuit) chip 25 covered and protected by a passivation film 26.
As shown in the plan view of FIG. The scintillator 23 is a sheet-like scintillator, and is bonded to a semiconductor substrate 27 on which the photodetectors 24 are integrally formed. The semiconductor substrate 27 is die-bonded to the base substrate 22.

The configuration of the one-dimensional radiation detection array 3 will be described with reference to an equivalent circuit diagram of FIG. The transmitted X-rays are converted into light by the scintillator 23 and then photoelectrically converted by the light detecting element 24 to become electric signals. The light detection element 24 is, for example, a photodiode formed of amorphous silicon. The electric charge obtained by the light detection element 24 is stored in the capacitor 31. Each capacitor 31 stores a charge proportional to the amount of received light, that is, the transmitted X-ray intensity. At the time of reading the charge, the switch elements 33 provided for the respective photodetectors 24 are sequentially opened and closed. As a result, the charges accumulated in each capacitor 31 are read out from the terminal 37 via the buffer circuit 32 and the switch element 33. This terminal 37 is connected to the amplifier 10 shown in FIG.
The switch element 34 is connected to the capacitor C for which the reading is completed.
And discharges the remaining charges to prepare for the next X-ray detection. The shift register 35 receives a clock signal from the terminal 38 to generate a read-out scanning control signal, and sequentially outputs the control signal to each signal-reading switch element 33.

The AND element 36 serves to prevent the malfunction of the switch element 33. One input terminal is supplied with a scanning signal of H (“1”) level at the read timing from the shift register 35, while a control signal for performing a gate operation on the scanning signal is supplied to the other input terminal via a terminal 39 from outside. Given. That is, A
A control signal of L (“0”) level is applied to the other input terminal of the ND element 36 during the non-reading period, and the scanning operation is cut off to inhibit the reading operation. A read operation is allowed by allowing a scan signal to be passed from the outside via a terminal 39 and passed through the scan signal.

The capacitor 31 is connected to the AND element 36.
All of the above elements can be collectively provided on the IC chip 25. The capacitor 31 is formed on the semiconductor substrate 27 together with the photodetector 24,
Alternatively, it can be dealt with by the junction capacitance of the photodiode.

The operation of reading the X-ray detection signal from the radiation detection array 3 is as follows. In each of the radiation detection arrays 3, the X-ray detection signals are sequentially read out in the arrangement order by closing the corresponding switch elements 33 in sequence with the H-level scanning signal sent from the shift register 35 in accordance with the arrangement from the head radiation detection element 21. Then, the data is transferred to the subsequent amplifier 10. An amplifier 10 is provided for each one-dimensional radiation detection array 3, and the X-ray detection signals transferred from the same one-dimensional radiation detection array 3 are amplified by the same amplifier 10. ing.

As shown in FIG. 6, the radiation detecting elements 21 collectively read out the X-ray detection signals at the same timing for each of the horizontal columns a1,. You. The radiation detection elements 21 in each of the horizontal rows a1,..., An correspond to one slice surface of the subject M, and an X-ray detection signal from one slice surface during the X-ray detection operation. It is always collected in a lump. as a result,
The subsequent collection and processing of the X-ray detection signal is performed quickly.

Subsequently, the X-ray CT of the X-ray CT
The detection operation of the line detector 2 will be described by taking the case of spiral scanning as an example. The X-ray tube 1 and the X-ray detector 2 have a rotation axis Z
(That is, around the subject M), the subject M moves linearly along the rotation axis Z, and as a result, X
The movement trajectory of the X-ray detector 1 and the X-ray detector 2 is represented by a spiral U in FIG. During scanning, the X-ray tube 1 radiates a fan-shaped X-ray beam FB and reads out an X-ray detection signal from the X-ray detector 2. Of course, the X-ray beam FB is shaped by the collimator 8 into a shape corresponding to a two-dimensional arrangement of the radiation detecting elements 21 of n × N.

At the beginning of the reading scan for the X-ray detection signal generated in each radiation detecting element 21 by the irradiation of the X-ray beam FB, first, as shown in FIG. The X-ray detection signals of the elements 21 are read out at the same time and are simultaneously transferred to the respective amplifiers 10. Next, each radiation detection element 21 located in the horizontal row a2
X-ray detection signals are read out at the same time, and are simultaneously transferred to the respective amplifiers 10. Hereinafter, the same operation is repeated, and finally, the X-ray detection signals of the respective radiation detecting elements 21 located in the horizontal row an are read all at once, and the respective amplifiers 1 are read out.
0 at the same time.
The line detection operation ends. Then, the same X-ray detection operation is repeated again at the next moving position.

In each X-ray detection operation performed in this manner, the thickness (width in the direction of the rotation axis Z) in which the X-ray beam FB is used is smaller than that of the X-ray detector arranged in one line. Since the line detectors 2 are arranged in n columns (in the direction of the rotation axis Z), the number becomes n times, and the use range of the X-ray beam can be expanded. Further, in each X-ray detection operation, since the X-ray detection signals of n slice planes (perpendicular to the rotation axis Z) can be obtained at the same time, the capability of collecting the detection signals is large, and the scanning area of the same size can be observed. For example, the imaging time is reduced, and the throughput of the X-ray CT apparatus is improved. In addition, since the operation time of the X-ray tube is shortened by shortening the imaging time and the temperature rise of the X-ray tube is suppressed, the rated capacity of the X-ray tube can be reduced.

The present invention is not limited to the above embodiment, but can be modified as follows. (1) In the above embodiment, a sheet-like scintillator was used as the scintillator of the radiation detection element, but a crystalline scintillator partitioned by an optical separator may be used.

(2) In the above embodiment, the readout scan in each one-dimensional radiation detection array 3 is configured to start from the first radiation detection element and end at the last radiation detection element. This is a divided readout configuration in which a front scan starting from the first radiation detection element and ending at the middle radiation detection element and a rear scan starting from the first radiation detection element at the middle and ending at the last radiation detection element proceed simultaneously. A modification in which an amplifier is provided for each of the front and rear scans is given as a modification.

(3) In the above embodiment, the radiation detecting element 2
1 and the read-out scanning IC chip 25 were mounted on the same substrate surface. However, as shown in FIG. 8, the radiation detection element 21 was arranged using a base substrate 41 having an L-shaped cross section. The IC chip 25 may be mounted on the other surface different from the surface. Further, as shown in FIG. 9, a narrow base substrate 42 is used, and the IC chip 25 is mounted on the back surface opposite to the radiation detecting element 21, and the radiation detecting element 21 and the IC chip 2 are connected by through-hole wiring (not shown).
5 may be connected. 8 and 9, when the one-dimensional radiation detection arrays 3 are arranged, the arrays 3 can be smoothly combined without overlapping.

(4) In the above embodiment, the case where the X-ray CT apparatus performs a spiral scan has been exemplified. However, in the present invention, the X-ray tube 1 and the X-ray detector 2 are operated while the subject M is stopped. The present invention can also be applied to a rotating imaging method.

(5) In the above embodiment, in the case of spiral scanning, the subject M is moved, but the subject M is stopped and the X-ray tube 1 and the X-ray detector 2 are moved linearly. There may be.

(6) In the above embodiment, the semiconductor substrate 27 on which the light detecting element 24 is formed and the IC chip 25 are die-bonded to the base substrate 22. However, these are formed by CCD elements (charge transfer elements). The replacement configuration can be given as a modification.

[0042]

According to the X-ray CT apparatus of the first aspect, the X-ray detecting means for obtaining an X-ray detection signal required for reconstructing an X-ray tomographic image has a two-dimensionally arranged radiation detecting element group. And 1
Since the X-ray detection signals for many slice planes can be obtained at the same time by one X-ray detection operation, the capability of collecting the X-ray detection signals is large. As a result, the throughput of the X-ray CT apparatus is improved. Further, the use efficiency of the X-ray beam is increased and the imaging time is shortened, so that the rated capacity of the X-ray tube can be reduced.

According to the X-ray CT apparatus of the second aspect, the amplifier for amplifying the X-ray detection signal output from each one-dimensional radiation detection array is one for a plurality of radiation detection element groups sharing the same amplifier. Since only one amplifier is required, there is an advantage that the number of necessary amplifiers can be reduced.

According to the X-ray CT apparatus of the third aspect, at the time of reading and scanning the X-ray detection signal, the X-ray CT from one slice plane is read out.
Since the line detection signals are collectively collected, the collection and processing of the X-ray detection signals can be performed quickly.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main configuration of an X-ray CT apparatus according to an embodiment.

FIG. 2 is a plan view showing an arrangement state of a one-dimensional radiation detection array in the X-ray detector.

FIG. 3 is a front view showing an arrangement state of a one-dimensional radiation detection array in the X-ray detector.

FIG. 4 is an explanatory diagram showing a detailed configuration of a one-dimensional radiation detection array.

FIG. 5 is an equivalent circuit diagram of the one-dimensional radiation detection array.

FIG. 6 is a schematic diagram illustrating a state of reading signals from a one-dimensional radiation detection array.

FIG. 7 is a perspective view showing a movement trajectory of an X-ray tube and an X-ray detector in spiral scanning.

FIG. 8 is a partial sectional view showing an X-ray detector according to a modification.

FIG. 9 is a partial cross-sectional view illustrating an X-ray detector according to another modification.

FIG. 10 is a schematic diagram showing an X-ray irradiation / detection system of a conventional X-ray CT apparatus.

FIG. 11 is a perspective view showing an example of a conventional X-ray detector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... X-ray tube 2 ... X-ray detector 3 ... One-dimensional radiation detection array 5 ... Moving mechanism 10 ... Amplifier 21 ... Radiation detection element 23 ... Scintillator 24 ... Light detection element 25 ... IC chip C ... Circular arc M ... Subject

Claims (3)

[Claims] 1. An X-ray generating means and an X-ray detecting means are arranged opposite to each other with a subject interposed therebetween, and the two means are rotated around the subject while exposing an X-ray beam from the X-ray generating means. In this case, in an X-ray CT apparatus for reconstructing an X-ray tomographic image of a subject by processing an X-ray detection signal output from the X-ray detection means at this time, the X-ray detection means includes a scintillator and a light detection Each of the one-dimensional radiation detection arrays is composed of a plurality of one-dimensional radiation detection arrays in which the radiation detection elements formed by combining the elements are arranged in a line. Line generating means and X
The one-dimensional radiation detection arrays are arranged so as to be substantially parallel to the rotation axis of the line detection means, and are arranged so that the one-dimensional radiation detection arrays are arranged in an arc shape. An X-ray CT apparatus, being arranged. 2. The X-ray CT apparatus according to claim 1, wherein each one-dimensional radiation detection array is configured such that each radiation detection element group is read out and scanned, so that X-ray detection signals are sequentially read out. And an X-ray CT apparatus configured to scan an X-ray detection element and transfer an X-ray detection signal read out to a common amplifier. 3. The X-ray CT apparatus according to claim 2, wherein at the time of scanning for reading out the X-ray detection signal, the radiation detection element groups arranged in a line in the circumferential direction in relation to the one-dimensional radiation detection array are X-rays. An X-ray CT apparatus configured to simultaneously read line detection signals.