CN111728628B

CN111728628B - A phantom for testing the axial performance of CT spiral scanning multi-planar reconstruction images

Info

Publication number: CN111728628B
Application number: CN202010579127.9A
Authority: CN
Inventors: 杜国生; 侯士国
Original assignee: Nuclover Technology Co ltd
Current assignee: Nuclover Technology Co ltd
Priority date: 2020-01-22
Filing date: 2020-06-23
Publication date: 2025-03-25
Anticipated expiration: 2040-06-23
Also published as: CN111728628A

Abstract

The invention relates to an axial performance test die body for a CT (computed tomography) scanning reconstruction image, which is characterized in that a body is an organic glass cube or cuboid, tungsten bead strings and tungsten wires for measuring the spatial resolution of the CT spiral scanning reconstruction image are respectively arranged in the body along X, Y, Z axial directions, 1-5 metal wires for measuring the thickness deviation of the CT spiral scanning reconstruction image are arranged on six surfaces of the body, the metal wires are obliquely arranged on the surfaces and are equidistantly, parallelly and centrally symmetrically arranged, the highest end of the metal wire positioned below and the lowest end of the metal wire positioned above adjacent to the highest end are positioned on the same horizontal line, and the included angle between the metal wire and the related surface is 18.4-45 degrees.

Description

CT spiral scanning multi-plane reconstruction image axial performance test die body

Technical Field

The invention relates to the technical field of medical CT (computed tomography) scanning reconstructed image performance test, in particular to an axial performance test of a CT spiral scanning reconstructed image, and specifically relates to an axial performance test die body of a CT spiral scanning multi-plane reconstructed image.

Background

At present, the medical CT scanning system of medical institution equipment in China has completed updating from single-row axial scanning CT to multi-row spiral scanning CT.

When CT scanning is performed in clinical diagnosis and examination, spiral scanning (namely, spiral scanning is commonly called) is adopted in heart and cerebral angiography and chest and abdomen disease examination, a detected person lying on an examination table moves along with the table during X-ray rotation irradiation, and the scanning and imaging speed is high, and the defect that the image quality is not better than that of the scanning commonly called axial scanning in which the examination table does not move during scanning is overcome.

In CT scanning, medical staff is required to perform multi-axial planar reconstruction by helical scanning after scanning and reconstructing a Z-axis tomographic XY plane image (cross-sectional image) in order to accurately determine the focus morphology, thereby obtaining a sagittal plane image (sagittal plane is a ZY plane along the front-back path of a human body lying in a horizontal plane, i.e., a ZY plane perpendicular to the ground and made along the Z-axis) and a coronal plane image (coronal plane is an XZ plane parallel to the ground and made along the left-right path of the human body, i.e., the X-axis), or three-dimensional reconstruction at any angle.

The quality management standard of the spiral scanning three-dimensional reconstruction image is not seen up to the present, CT manufacturers are all called isotropy, but the detailed technical indexes and the proof files are not seen. In clinical radiodiagnosis in hospitals, the method for estimating the morphology and the resolution of a focus three-dimensional image by using the performance parameters of the reconstructed XY plane image of the CT system axis scanning existing detection die body has the defect of technical strictness, and is particularly suitable for a wide-beam multi-row spiral CT scanning system.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention aims to provide the axial performance test die body for the CT spiral scanning multi-plane reconstructed image, which has reasonable design, simple structure, firmness, reliability, convenient use and easy maintenance, can be used for the axial performance test of the CT spiral scanning multi-plane reconstructed image, provides measured data for the three-dimensional image performance evaluation of a reconstructed focus, and can also be used for the measurement of the performance of the CT axial scanning reconstructed image.

In order to achieve the above purpose, the invention adopts the following technical scheme:

a CT helical scan multi-planar reconstructed image axial performance test phantom, comprising:

the body is a cube or cuboid of organic glass with upper, lower, left, right, front and back,

The material of the body can also be selected from other organic light solid materials, such as polycarbonate PC, polystyrene PS, nylon or bakelite,

The tungsten wire for measuring the spatial resolution of the CT spiral scanning multi-plane reconstruction image, namely the high contrast resolution, is arranged in the body along the Z-axis direction, the diameter of the tungsten wire is 0.05-0.15 mm, a string of tungsten beads for measuring the spatial resolution of the CT spiral scanning multi-plane reconstruction image, namely the high contrast resolution, is respectively arranged along the X, Y-axis direction, the tungsten beads comprise a plurality of tungsten beads, the diameter of the tungsten beads is 0.2-0.3mm, the bead spacing is 5mm, and the three tungsten wires and the tungsten beads are not overlapped and crossed on the same plane.

The design scheme has the advantages that the data used for spiral scanning three-dimensional reconstruction images are obtained by continuous scanning acquisition when an examination bed (in the Z-axis direction) moves, the dot-shaped image performance of tungsten wire segments and tungsten beads on an XY plane intersecting the Z-axis is almost indistinguishable, the difference of the MTF values of the spatial resolution is calculated by using two dot-shaped graphs on the same plane and is less than 0.5Lp/cm (in the range of actual measurement 5-16 Lp/cm), and the two values are equal or are different from each other. Whereas in reconstructing the XZ plane transverse to the X-axis YZ plane and transverse to the Y-axis, the hardening artifacts of the tungsten filament in a single direction are evident, the isotropy of the tungsten beads in the three-dimensional scan is not seen with its hardening artifact effects. The MTF value measured from the bead point image in the same XZ or YZ plane may be higher than 1.0Lp/cm than the MTF value measured from the tungsten wire segment dot image. Therefore, the scheme is that tungsten wires are arranged in the Z-axis direction, and tungsten bead strings (the bead spacing is 5 mm) are arranged in the X-axis direction and the Y-axis direction. The MTF value of the spatial resolution of each image of various scanning layer thicknesses can be continuously measured in the Z-axis direction and the length range of the tungsten filament, but the MTF value of the spatial resolution of each image of the various scanning layer thicknesses cannot be measured in the X-axis direction or the Y-axis direction, namely the MTF value of the spatial resolution of the image of the point image with the bead can be measured.

The six surfaces of the body are respectively provided with 1-5 tungsten wires with the diameter of 0.1-0.3 mm for measuring the thickness deviation of CT spiral scanning multi-plane reconstruction images, the tungsten wires are obliquely arranged at the left, right, high or left, right of the surface, are equidistantly and parallelly arranged, the highest end of the tungsten wire positioned below and the lowest end of the tungsten wire positioned above adjacent to the tungsten wire are positioned on the same horizontal line, the included angle between the oblique lines on the upper surface and the lower surface for measuring the thickness deviation of scanning layers transverse to the Z axis and the front surface or the rear surface of the body is alpha ₁, the included angle between the oblique lines on the front surface and the rear surface for measuring the thickness deviation of scanning layers transverse to the X axis and the left surface or the right surface of the body is alpha ₂, the included angle between the oblique lines on the left surface and the right surface for measuring the thickness deviation of scanning layers transverse to the Y axis and the upper surface or the lower surface of the body is alpha ₃, the included angle alpha ₁、α₂、α₃ is 18.4-45 degrees,

The tungsten wire on the surface of the body can also adopt copper wire or steel wire or tin wire;

Further, the tungsten wires on six surfaces of the organic glass body are arranged in grooves on the surface of the body, three tungsten wires are respectively arranged on the upper surface and the lower surface, two tungsten wires are respectively arranged on the left surface, the right surface, the front surface and the rear surface, the diameter of each tungsten wire is 0.1mm, all tungsten wires are symmetrically arranged with the center of the surface, and the included angle alpha ₁、α₂、α₃ is 26.6 degrees;

Further, the method comprises the steps of,

The body is provided with a first through hole along the X axis,

The body is provided with a second through hole along the Y axis,

The body is provided with a third through hole along the Z axis,

The tungsten wire and the tungsten bead string for measuring the spatial resolution of the image are respectively arranged at the central axis position in the cylindrical support protection rod matched with the through hole;

further, the body is a cuboid, the long edge of the cuboid is along the Z-axis direction, and four edges of the body along the Z-axis direction are provided with plane or arc surface chamfers;

The test die body provided by the invention has the advantages of reasonable design, simple structure, firmness, reliability, convenience in use, easiness in maintenance and the like, has high test efficiency, can meet the requirement of axial performance test of CT spiral scanning multi-plane reconstructed images, and can also be used for measuring the performance of CT axial scanning reconstructed images.

The test die body has high test efficiency, the data of the test die body is scanned by one spiral, all commercial spiral CT scanning systems can reconstruct three plane images of XY, XZ and YZ, and the layer thickness deviation (mm) and the spatial resolution MTF (Lp/mm) of the reconstructed images can be calculated by using the existing image processing technology to compile related software.

The software calculates the layer thickness deviation (mm) of the reconstructed image, namely analyzes the half-width length of the corresponding metal wire image on the XY, XZ and YZ plane images obtained by reconstructing the computed tomography test die body, and calculates the accurate value of the scanned reconstructed layer thickness.

The software calculates the spatial resolution MTF (Lp/mm) of an image, namely, the software analyzes the point-shaped image of a triaxial set tungsten wire (for example, the diameter of 0.05mm and the total length of 50-200 mm) or tungsten beads obtained by reconstructing a plane of a computed tomography test die body, analyzes a two-dimensional line diffusion function of the point-shaped image by using the point diffusion function of the prior art, calculates and gives a modulation transfer function curve (MTF), marks the contrast on the curve and the corresponding spatial resolution value, and is line-to-centimeter (Lp/cm).

The invention relates to a water model, which is connected with the front or the back of a test model, and related software is compiled by using the existing image processing technology, so that the following performances of the spiral scanning water model for reconstructing a multi-plane image, namely the CT value, the image noise, the uniformity and the Low Contrast Detectability (LCD) of water can be measured and calculated.

Drawings

The invention has the following drawings:

Figure 1 is a schematic diagram of a test phantom,

Figure 2 is a schematic view of the upper surface of the test die body,

Figure 3 is a schematic view of the lower part of the test die,

Figure 4 is a schematic diagram of the left and right sides of the test die body,

Figure 5 is a schematic view of the front of the test die,

Figure 6 is a schematic view of the rear of the test die body,

Fig. 7-11 show specific numbers of wires.

FIG. 12 is a schematic diagram showing the layout of three tungsten filaments and tungsten bead strings

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1-12, fig. 1 is a schematic perspective view of the present invention, opposite to the rear face 6 of the mold body, and fig. 2-6 are six-face expanded schematic views of the present invention, which are expanded based on the front face 5 of the mold body.

The invention relates to an axial performance test die body for CT spiral scanning multi-plane reconstruction images, which comprises:

The main body 20 is a cube or rectangular cylinder with three pairs of surfaces, i.e. an upper surface 1, a lower surface 2, a left surface 3, a right surface 4, a front surface 5 and a rear surface 6 (see fig. 1), the main body 20 is made of an organic light solid material, preferably an organic material with a density close to that of water, such as polycarbonate PC, high-density polyethylene, polystyrene PS, organic glass (PMMA, also called acryl), nylon or bakelite, and the main body is made of organic glass.

The tungsten wire and the tungsten bead string for measuring the spatial resolution of CT spiral scanning multi-plane reconstruction images, namely high contrast resolution, are arranged in the body along the X, Y, Z-axis direction, and concretely, the embodiment (see figure 12) is that a tungsten wire 10 is arranged along the Z-axis direction, a string of tungsten beads is respectively arranged along the X, Y-axis direction, the X-axis is a first tungsten bead string 13, the Y-axis is a second tungsten bead string 14, the bead spacing is 5mm, the three tungsten wires and the tungsten bead strings (namely the tungsten wire 10, the first tungsten bead string 13 and the second tungsten bead string 14) are not overlapped and crossed on the same plane, the diameter of the tungsten wire is 0.05-0.15 mm, and the diameter of the tungsten bead is 0.2-0.3mm. The three tungsten wires and tungsten bead strings are not overlapped and not contacted with each other, which means that intersecting contact points do not exist between the tungsten wire 10 and the two tungsten bead strings 13 and 14 in space, when a scheme of arranging supporting rods (supporting protection rods) is adopted, the three tungsten wires and tungsten bead strings are not overlapped with each other, which means that intersecting contact points do not exist between the supporting rods of the three tungsten wires and tungsten bead strings in space, so as to avoid overlapping of scanning images, fig. 12 shows an embodiment of a layout of the tungsten wires and the tungsten bead strings, and the supporting protection rods for fixing the tungsten wires and the tungsten bead strings are inserted into holes 7, 8 and 9 in fig. 1. The diameter of the tungsten filament is 0.05-0.15 mm, wherein 0.05mm,0.07mm,0.1mm,0.12mm and 0.15mm are all selectable diameters.

The tungsten filament 10 and the tungsten bead strings 13 and 14 in the body 20 are respectively perpendicular to three pairs of surfaces of the die body, as shown in fig. 12, the tungsten filament 10 in the Z-axis direction is perpendicular to the front (supine head position of a patient, namely CT frame position), the back (foot position of a patient), the tungsten bead string 14 in the Y-axis direction is perpendicular to the upper surface and the lower surface, and the tungsten bead string 13 in the X-axis direction is perpendicular to the left surface and the right surface. The arrangement of the tungsten filament and the spatial position of the tungsten bead string takes into account the uniformity of the reconstructed image and avoids the interference of X-ray scan hardening artifacts.

The six surfaces of the body 20 are respectively provided with 1-5 metal wires 30 for measuring the thickness deviation of the CT spiral scanning reconstructed image layer, and the metal wires can be tungsten wires, copper wires, steel wires or tin wires. The number of the metal wires on each surface can be the same, for example, 2,3,4 or 5 metal wires on each surface can be different, the metal wire materials can be the same or different, and the metal wires can be selected according to the mould body length and the ratio between the metal wire image length and the scanning layer thickness, and particularly, refer to fig. 7-11. In the embodiment shown in fig. 2-6 (schematic views of the six surfaces of the die body), two wires are arranged on the front, rear, left and right surfaces, three wires are arranged on the upper and lower surfaces, and tungsten wires are used as the wires in the embodiment.

The wires 30 are all arranged obliquely on the surface, and are mutually parallel and equidistantly arranged.

In one embodiment of the invention, 3 wires are arranged on the upper surface 1 and the lower surface 2 in plan view and used for collecting layer thickness information (spiral scanning and axial scanning) of a reconstructed image by cross section (XY plane) scanning, the wires 30 are obliquely arranged to be low on the left and high on the right or low on the left and high on the right, the highest ends 31 of the wires positioned below and the lowest ends 32 of the wires positioned above adjacent to the highest ends are positioned on the same horizontal line, and the aim of arrangement is that continuous layer thickness information is collected on each layer of images reconstructed by wide-range spiral scanning (or axial scanning) in the length of a die body, namely, projections of the wires 30 are not interrupted or overlapped during multi-layer continuous scanning reconstruction.

Two wires are arranged on the plane view of the left surface 3 and the right surface 4 and are used for collecting the layer thickness information of the coronal (XZ plane) scanning reconstructed image.

Two wires are provided on the front 5 and rear 6 plan views for acquiring sagittal (YZ plane) scan reconstructed image layer thickness information.

The metal wires 30 on the six surfaces of the body 20 are preferably tungsten wires, the tungsten wires can be adhered on the surface of the die body, or can be arranged below the surface layer of the die body by other methods, in the embodiment of fig. 1-6 of the invention, the metal wires (tungsten wires) 30 are arranged in the grooves 301 on the surface of the body 20, three tungsten wires are respectively arranged on the upper surface 1 and the lower surface 2, and two tungsten wires are respectively arranged on the left surface 3, the right surface 4, the front surface 5 and the rear surface 6. Because the partial volume effect of CT scanning imaging is also called as the volume effect, the image contrast of images reconstructed by scanning wires of the same material and the same wire diameter in the same background material with different layer thicknesses can be greatly different, the diameter of the tungsten wire is 0.1-0.3 mm, which is an experimental preferred value of various materials and wire diameters, wherein 0.1mm,0.2mm and 0.3mm are all selectable diameters.

The parallel metal wires (tungsten wires) can be biased on the surface of the die body (namely, are arranged close to one side), but the preferable scheme is that all tungsten wires are symmetrically arranged with the center of the surface, so that the tungsten wires are uniformly distributed, and the test positioning and the data processing programming are convenient, and particularly refer to fig. 1-6.

The inclined lines on the upper surface 1 and the lower surface 2 for measuring the cross section (transverse Z axis) scanning layer thickness deviation form an angle alpha ₁ with the front surface 5 or the rear surface 6 of the body 20, the inclined lines on the front surface 5 and the rear surface 6 for measuring the sagittal plane (transverse X axis) scanning layer thickness deviation form an angle alpha ₂ with the left surface 3 or the right surface 4 of the body 20, the inclined lines on the left surface 3 and the right surface 4 for measuring the coronal plane (transverse Y axis) scanning layer thickness deviation form an angle alpha ₃ with the upper surface 1 or the lower surface 2 of the body 20, the angle of the angle alpha ₁、α₂、α₃ is 18.4-45 degrees, and the angle of the angle alpha ₁、α₂、α₃ can be different from each other or the same. When the included angle is 45 degrees, the length of the metal wire scanning reconstruction image is equal to the thickness of the scanning reconstruction layer. When the included angle is 18.4 degrees, the length of the metal wire scanning reconstruction image is three times of the thickness of the scanning reconstruction layer (the projection relation formula is 1/tan alpha), so that the measurement accuracy of a thinner layer can be improved, but the difficulty of die body placement and alignment is also increased. The optimal selection of the included angle alpha ₁、α₂、α₃ is 26.6 degrees, and the half-width length of the metal wire scanning reconstruction image is twice the thickness of the scanning reconstruction layer. This can form a series of products.

The tungsten wire and the tungsten bead string can be directly arranged in the die body, for example, the die body is manufactured into a whole during forming. In order to facilitate the processing and manufacturing of the die body and the testing and using of the die body, the body 20 of the invention is provided with through holes 7, 8 and 9 along the three axial directions of X, Y, Z, the tungsten wire and the tungsten bead string are arranged on the axial line position (not shown in the figure) in a cylindrical supporting protection rod which is the same as the die body in material, and the size of the supporting protection rod is matched with the size of the through hole, so that the manufacturing precision is ensured, and the assembly and the use are convenient.

The body 20 may be a cube or a cuboid (including 6 faces are rectangular, or 2 faces are square, and 4 faces are rectangular), and specifically, may be designed into an independent die body or be combined with other CT imaging performance testing modules into a multifunctional testing die body according to different requirements.

In an alternative embodiment, the die body side length may be 7 to 24cm, for example, 7 to 7, 9 to 9, 11 to 11, 12 to 12, 15 to 15, 17 to 17, 20 to 20, 22 to 22 or 24 to 24cm cubic die bodies are optional examples, and for the rectangular die body, the Z axial length may be 1.1, 1.3, 1.5, 1.7 or 2.0 times the front and rear side lengths, respectively, such rectangular test die bodies may be used in the head die or the abdomen die, and the test die body with side length 20, 22 or 24cm cubic may be used independently.

The specific arrangement of the wires 30 is shown in fig. 7 to 11, in which the dotted lines are only used to indicate that "the highest end 31 of the wire 30 located below and the lowest end 32 of the wire 30 located adjacent above are on the same horizontal line".

FIG. 7 shows 1 wire 30 with an angle α _1、2、3 of 45, which can be used for a scan test with a layer thickness of 10 mm;

fig. 8 shows a wire 30 comprising 2 wires, with an angle α _1、2、3 of 26.56 ° (approximately 26.6 °);

Fig. 9 shows 3 wires 30 with an angle α _1、2、3 of 18.4, which can be used for scanning tests with a layer thickness of 5 mm.

The body 20 of the present invention may be a cube or a cuboid, and the length of the cuboid may be along the Z-axis direction.

For use with other test patterns, the four sides of the body 20 along the Z-axis direction of the present invention may be provided with planar or rounded corners.

The test die body, the test using method and the data processing method can be carried out by referring to the prior art, and are not described in detail.

What is not described in detail in this specification is prior art known to those skilled in the art.

The method comprises the following steps:

Brief use description of CT spiral scanning multi-plane reconstruction image axial performance test die body

The test die body can be designed into an independent die body or combined with other CT imaging performance test modules into a multifunctional test die body by selecting different shapes, sizes and dimensions according to different requirements.

When the axial performance index test of the CT spiral scanning reconstructed image is implemented, the die body is arranged on the scanning inspection bed and close to the machine frame end, the Z axis of the die body is parallel to the scanning central axis, the height of the bed is adjusted, and the center position of the die body is adjusted to the system scanning center axis position under the indication of positioning light. Scanning the front and side positioning images one by one. On the system image display interface, the mold bodies are checked and corrected to be correctly placed, namely, the upper surface and the lower surface are horizontal, the left surface and the right surface are vertical, and the front surface and the rear surface are vertical.

Setting up a spiral scanning acquisition plan, namely setting up standard kV, mA, scanning time of each turn, scanning range (length), screw pitch, layer thickness (the thinnest layer thickness is preferably selected during spiral acquisition), reconstruction algorithm and the like. After the thickness of the reconstructed layer is designed and the axial reconstruction program of the system is clicked, the system automatically reconstructs Z, Y, X triaxial plane images, the reconstructed images are sent to an image workstation, and DICOM image data are copied by using an optical drive.

The layer thickness deviation (mm) and the spatial resolution MTF (Lp/mm) of the reconstructed image can be calculated using related software compiled by the existing image processing technology. Layer thickness dimensional deviations can also be measured with the naked eye using DICOM inspection software "RadiAnt DICOM Viewer (64-bit) Medixant".

Claims

1. A CT spiral scanning multi-planar reconstruction image axial performance test phantom, characterized in that it includes:

The body (20) is a rectangular parallelepiped having a top (1), a bottom (2), a left side (3), a right side (4), a front side (5), and a back side (6). The body (20) is made of an organic light solid material, including polycarbonate PC, polystyrene PS, organic glass, nylon or bakelite.

Tungsten beads (13, 14) and tungsten wires (10) for measuring the spatial resolution, i.e., high contrast resolution, of CT spiral scanning reconstructed images are arranged in the body (20) along the three axes of X, Y, and Z, wherein a string of tungsten beads (13, 14) is arranged along the X and Y axes respectively, the diameter of the tungsten beads is 0.2-0.3 mm, and the distance between the beads is 5 mm, and a tungsten wire (10) is arranged along the Z axis, the diameter of the tungsten wire is 0.05-0.15 mm, and the three tungsten wires and tungsten beads arranged in the three axes are on the same plane and do not overlap or cross each other;

The six surfaces of the body (20) are each provided with 2 to 5 metal wires (30) for measuring the layer thickness deviation of the CT spiral scanning reconstruction image. The metal wires (30) are all arranged obliquely on the surface, with the left side lower than the right side or the left side higher than the right side, equidistantly and in parallel. The highest end (31) of the metal wire located at the bottom and the lowest end (32) of the metal wire located at the top adjacent to it are located on the same horizontal line. The angle between the oblique lines on the top (1) and the bottom (2) for measuring the scanning layer thickness deviation transverse to the Z axis and the front (5) or the back (6) of the body (20) is _α1 . The angle between the oblique lines on the front (5) and the back (6) for measuring the scanning layer thickness deviation transverse to the X axis and the left side (3) or the right side (4) of the body (20) is _α2 . The angle between the oblique lines on the left side (3) and the right side (4) for measuring the scanning layer thickness deviation transverse to the Y axis and the top (1) or the bottom (2) of the body (20) is α3 _. The angles α ₁ , α ₂ , and α ₃ are 18.4° to 45°, the diameter of the metal wire is 0.1 to 0.3 mm, and the metal wire is tungsten wire, copper wire, steel wire, or tin wire.

2. The CT spiral scanning multi-planar reconstruction image axial performance test phantom as claimed in claim 1, characterized in that: the body (20) is an organic glass body, the metal wires (30) provided on the six surfaces thereof are tungsten wires, the metal wires (30) are arranged in grooves (301) on the surface of the body (20), three tungsten wires are respectively provided on the upper side (1) and the lower side (2), two tungsten wires are respectively provided on the left side (3), the right side (4), the front side (5), and the back side (6), the diameter of the tungsten wire is selected to be 0.1 mm, all the tungsten wires are arranged symmetrically with respect to the center of the surface where they are located, and the angles _α1 , _α2 , and _α3 are all 26.6°.

3. The CT spiral scanning multi-planar reconstruction image axial performance test phantom according to claim 1 or 2, characterized in that:

The body (20) is provided with a first through hole (7) along the X-axis direction.

The body (20) is provided with a second through hole (8) along the Y-axis direction.

The body (20) is provided with a third through hole (9) along the Z-axis direction.

The tungsten beads (13, 14) and the tungsten wire (10) are respectively arranged at the center of a supporting protection rod matched with the first to third through holes (7, 8, 9).

4. The CT spiral scanning multi-planar reconstruction image axial performance test phantom as described in claim 1 or 2 is characterized in that: the main body (20) is a rectangular parallelepiped with its long side along the Z-axis direction, and the four sides of the main body (20) along the Z-axis direction are provided with plane or arc chamfers.

5. The CT spiral scanning multi-planar reconstruction image axial performance test phantom as described in claim 3 is characterized in that: the main body (20) is a rectangular parallelepiped with its long side along the Z-axis direction, and the four sides of the main body (20) along the Z-axis direction are provided with plane or arc chamfers.