Method for determining longitudinal position of a combined phantom, computer readable storage medium and ct device

Abstract

The application discloses a method for determining longitudinal position of a combined phantom, a computer readable storage medium and a CT device. The method comprises: scanning the combined phantom to obtain a positioning image of the combined phantom, the combined phantom being fixed to a bed plate and extending out of the bed plate, an axial direction of the combined phantom being parallel to the longitudinal direction, the combined phantom comprising a plurality of phantoms and one of the phantoms being a slice thickness phantom; identifying the plurality of phantoms on the positioning image; and taking the axial center of the slice thickness phantom as the longitudinal position of the combined phantom. The method for determining longitudinal position of a combined phantom, the computer readable storage medium and the CT device can automatically align the phantom position quickly by determining the longitudinal position of the combined phantom through the positioning image.

Description

Technical Field

[0001] This invention relates to a method for determining the longitudinal position of a composite mold. Background Technology

[0002] When CT manufacturers release a new software version, all field systems will be upgraded to that version. If some changes require overall coordination, these affected systems will all require field service, which is a significant workload for service engineers. One solution is to instruct customers to place the phantom on the correct support and automatically align it.

[0003] On the other hand, on the production line, the mold body is automatically aligned in the Y direction, but manual alignment is required in the Z direction. Summary of the Invention

[0004] In view of this, the present invention proposes a method for determining the longitudinal position of a combined phantom, a computer-readable storage medium, and a CT device.

[0005] According to a first aspect of the present invention, a method for determining the longitudinal position of a composite phantom is provided, comprising: scanning the composite phantom to obtain a positioning image thereof, the composite phantom being fixed to a bed board and extending beyond the bed board, the axial direction of the composite phantom being parallel to the longitudinal direction, the composite phantom comprising a plurality of phantoms, one of which is a layer-thickness phantom; identifying the plurality of phantoms on the positioning image; and taking the axial center of the layer-thickness phantom as the longitudinal position of the composite phantom.

[0006] In one embodiment, identifying the plurality of phantoms on the positioning image includes: for each read i, calculating the number C of channels greater than the air HU value. i , 0≤i≤N-1, where N is the total number of reads; number of smoothing channels C i Curve; the length of the mold between the starting position of the non-air portion that is larger than the minimum radial size of the mold and the point where the radial size changes is taken as the measured length of the current mold; if the measured length of the current mold is close to the length of the current mold, the current mold is identified.

[0007] In one embodiment, the number of smoothing channels C i The curves include: classifying adjacent reads with similar channel counts as belonging to the same module; and averaging the channel count of the same module.

[0008] In one embodiment, the number of channels being close to means: |C i -C i+1 | <T C

[0009] Among them, T C It is a positive integer threshold.

[0010] In one embodiment, TC =4.

[0011] In one embodiment, the measurement length of the current phantom being close to the length of the current phantom means: |L j -L j,default | <T L

[0012] Among them, L j L is the measured length of phantom j. j,default T is the length of the phantom j. L It is a positive threshold.

[0013] In one embodiment, T L = 2mm.

[0014] In one embodiment, the longitudinal direction is the direction in which the bed board moves in and out of the computed tomography (CT) scanner.

[0015] According to a second aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, characterized in that the program, when executed by a processor, implements the method described above.

[0016] According to a third aspect of the present invention, a computed tomography (CT) device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the program to implement the method described above.

[0017] The method for determining the longitudinal position of the combined phantom, the computer-readable storage medium, and the CT device of the present invention determine the longitudinal position through the positioning image of the combined phantom, and can quickly and automatically align the phantom position. Attached Figure Description

[0018] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which will make the above and other features and advantages of the present invention more apparent to those skilled in the art. In the drawings:

[0019] Figure 1 This is a flowchart illustrating a method for determining the longitudinal position of a combined phantom according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of a positioning image according to an embodiment of the present invention.

[0021] Figure 3 This is a schematic diagram of the process for identifying a plurality of phantoms on a positioning image according to an embodiment of the present invention.

[0022] Figure 4 This is a graph showing the number of channels with a HU value greater than the air value as a function of the reading, according to an embodiment of the present invention.

[0023] Figure 5 This is a flowchart illustrating the smoothing of the channel number curve according to an embodiment of the present invention.

[0024] The reference numerals used in the above figures are as follows:

[0025] 100 Method 108 Layer Thickness Mold

[0026] S102, S104

[0027] S106, S108

[0028] Step 110 Water Model

[0029] S110, S112

[0030] S114, S116

[0031] S118

[0032] 102 Combined Module 112 Support

[0033] 104 Focus calibration phantom; 114 Bed board

[0034] 106 high-resolution phantoms Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the present invention clearer, the following embodiments are provided to further illustrate the present invention in detail.

[0036] Figure 1 This is a flowchart illustrating a method 100 for determining the longitudinal position of a combined phantom according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the positioning image 116 according to an embodiment of the present invention. Figure 1 , 2 As shown, the method 100 for determining the longitudinal position of the combined module includes steps S102, S104, and S106.

[0037] In step S102, the combined phantom 102 is scanned to obtain its positioning image 116. The combined phantom 102 is fixed to the bed board 114 by, for example, a bracket 112 and extends beyond the bed board 114. Therefore, as seen in the positioning image 116, the combined phantom 102 is surrounded by air. It should be noted that in this invention, the longitudinal direction refers to the direction in which the bed board enters and exits the computed tomography scanning device, i.e., the Z direction. The axial direction of the combined phantom 102 is parallel to the longitudinal direction. The combined phantom 102 includes a plurality of phantoms, one of which is a slice thickness phantom 108. In this embodiment, the combined phantom 102 includes a focus calibration phantom 104, a high-resolution phantom 106, a slice thickness phantom 108, and a water phantom 110.

[0038] In step S104, the aforementioned phantom is identified on the positioning image 116. Figure 3 This is a schematic diagram illustrating the process of identifying a plurality of phantoms on a positioning image according to an embodiment of the present invention. Figure 3 As shown, in this embodiment, step S104 may include steps S108, S110, S112, and S114.

[0039] In step S108, for each read i, the number C of channels greater than the air HU value is calculated. i , 0≤i≤N-1, where N is the total number of reads. Figure 4 The number of channels C greater than the air HU value according to an embodiment of the present invention i The graph shows the reading process.

[0040] In step S110, the number of smoothing channels C i curve.

[0041] In step S112, the length of the non-air portion that is larger than the minimum radial size of the mold body is taken as the measured length of the current mold body.

[0042] In step S114, if the measured length of the current model is close to the length of the current model, the current model is identified.

[0043] Figure 5 The number of smoothing channels C according to an embodiment of the present invention i A flowchart illustrating the curve. (For example...) Figure 5 As shown, the number of smoothing channels C i Step S110 of the curve includes steps S116 and S118.

[0044] In step S116, adjacent reads with similar channel numbers are determined to belong to the same module. Similar channel numbers can be represented as:

[0045] |C i -C i+1 | <T C

[0046] Among them, T C It is a positive integer threshold. In this embodiment, T C =4.

[0047] In step S118, the average number of channels for the same module is calculated.

[0048] In step S114, "the measured length of the current model is close to the length of the current model" means that:

[0049] |L j -L j,default | <TL

[0050] Among them, L j L is the measured length of phantom j. j,default T is the length of the phantom j. L It is a positive threshold. In this embodiment, T L = 2mm.

[0051] like Figure 1 As shown, after step S104 of identifying the phantom from positioning image 116, in step S106, the axial center of the layer thickness phantom 108 is taken as the longitudinal position of the combined phantom 102.

[0052] After calculating the longitudinal position of the combined phantom, the positions of other phantoms can be checked based on this position and the default distances of each phantom in the configuration table. If all phantoms can cover the scanned longitudinal range, then the longitudinal positions of the phantoms are confirmed.

[0053] According to another aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements a method 100 for determining the longitudinal position of a combined phantom.

[0054] According to another aspect of the present invention, a computed tomography (CT) device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the program, implements a method 100 for determining the longitudinal position of a composite phantom.

[0055] The method for determining the longitudinal position of the combined phantom, the computer-readable storage medium, and the CT device of the present invention determine the longitudinal position through the positioning image of the combined phantom, and can quickly and automatically align the phantom position.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for determining the longitudinal position of a composite phantom (102), comprising: The combined phantom (102) is scanned to obtain its positioning image (116). The combined phantom (102) is fixed to the bed board (114) and extends beyond the bed board (114). The axis of the combined phantom (102) is parallel to the longitudinal direction. The combined phantom (102) includes a plurality of phantoms, one of which is a layer-thickness phantom (108). Utilizing a number of channels greater than the air HU value and number of smoothing channels The curve identifies the plurality of phantoms on the positioning image (116); The longitudinal position of the combined mold (102) is taken as the axial center of the layer thickness mold (108).

2. The method as described in claim 1, characterized in that, in Identifying the plurality of phantoms on the positioning image (116) includes: For each read i, calculate the number of channels greater than the air HU value. , , This is the total number of reads; number of smooth channels curve; The length of the non-air portion larger than the minimum radial size of the phantom is taken as the measurement length of the current phantom. If the measured length of the current phantom is close to the length of the current phantom, then the current phantom is identified.

3. The method as described in claim 2, characterized in that, The number of smoothing channels The curves include: Adjacent reads with similar channel numbers are identified as belonging to the same module; The average number of channels for the same module.

4. The method as described in claim 3, characterized in that, The term "close to" means: in, It is a positive integer threshold.

5. The method as described in claim 4, characterized in that, 。 6. The method as described in claim 2, characterized in that, The phrase "the measured length of the current phantom is close to the length of the current phantom" means: in, It is the model j It is the model j , It is a positive threshold.

7. The method of claim 6, characterized in that, 。 8. The method as described in claim 1, characterized in that, The longitudinal direction refers to the direction in which the bed board enters and exits the computed tomography (CT) scanner.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1 to 8.

10. A computed tomography (CT) scanner, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1 to 8.

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