阅读说明：本技术 一种用于评估tcm与ir算法临床影像质量的新型ct模体 (Novel CT (computed tomography) phantom for evaluating clinical image quality of TCM (TCM) and IR (Infrared radiation) algorithms ) 是由 何丽娟 张岭 何廷贵 殷春许 王明明 丁炎强 宋远超 章诚 程皖燕 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种用于评估TCM与IR算法临床影像质量的新型CT模体,具体涉及CT模体技术领域,包括模体本体,所述模体本体的一端设置有主模块一,且模体本体的另一端设置有主模块六,所述主模块一的一侧设置有主模块二,所述主模块二的一侧设置有主模块三,所述主模块三的一侧设置有主模块四,所述主模块四的一侧设置有主模块五。本发明不仅考虑了体型因素对新型技术在临床性能方面的影响,还考虑了TCM技术以及IR算法对CT值精度、分辨力和噪声的影响,以及体型-噪声函数、调制传递函数,不同尺寸的模体之间将采用锥形匀质模体进行过渡,减少了边缘效应,同时融入物理质控的测试模块,实现了对降低CT剂量的新技术TCM以及IR算法进行性能评估测试。(The invention discloses a novel CT (computed tomography) die body for evaluating clinical image quality of TCM (TCM) and IR (infrared) algorithms, and particularly relates to the technical field of CT die bodies. The invention not only considers the influence of body type factors on the clinical performance of the novel technology, but also considers the influence of TCM technology and IR algorithm on CT value precision, resolution and noise, body type-noise function and modulation transfer function, and conical homogeneous models are adopted for transition among models with different sizes, thereby reducing edge effect, and simultaneously integrating a test module of physical quality control, and realizing performance evaluation test of the novel technology TCM and IR algorithm for reducing CT dosage.)

1. A novel CT phantom body for evaluating TCM and IR algorithm clinical image quality, includes phantom body (1), its characterized in that: one end of the die body (1) is provided with a first main module (2), the other end of the die body (1) is provided with a sixth main module (7), one side of the first main module (2) is provided with a second main module (3), one side of the second main module (3) is provided with a third main module (4), one side of the third main module (4) is provided with a fourth main module (5), and one side of the fourth main module (5) is provided with a fifth main module (6);

the die body (1) is made of polyethylene materials, the diameters of the first main module (2), the second main module (3), the third main module (4), the fourth main module (5), the fifth main module (6) and the sixth main module (7) are sequentially reduced, a connecting module I (9), a connecting module II (10), a connecting module III (11), a connecting module IV (12) and a connecting module V (13) are sequentially arranged at the joint of the first main module (2), the second main module (3), the third main module (4), the fourth main module (5), the fifth main module (6) and the sixth main module (7), and the first connecting module (9), the second connecting module (10), the third connecting module (11), the fourth connecting module (12) and the fifth connecting module (13) are all in conical uniform die body transition.

2. The novel CT phantom for evaluating clinical image quality of TCM and IR algorithms according to claim 1, wherein: and a physical quality control analysis module is integrated into each main module of the die body (1).

3. The novel CT phantom for evaluating clinical image quality of TCM and IR algorithms according to claim 1, wherein: a fixing rod (8) is installed in the center of the die body (1), and one end of the fixing rod (8) penetrates through the interiors of the first main module (2), the second main module (3), the third main module (4), the fourth main module (5), the fifth main module (6) and the sixth main module (7).

4. The novel CT phantom for evaluating clinical image quality of TCM and IR algorithms according to claim 1, wherein: the testing device comprises a main module I (2), a main module II (3), a main module III (4), a main module IV (5), a main module V (6) and a main module VI (7), wherein a first layer module (14) is arranged inside each of the main modules I (2), the main module II (3), the main module III (4), the main module IV (5), the main module V (6) and the main module VI (7), a second layer module (15) is arranged on one side of each first layer module (14), and a testing module for positioning light precision deviation and.

5. The novel CT phantom for evaluating clinical image quality of TCM and IR algorithms according to claim 4, wherein: the interior of the first layer module (14) is provided with an insert material (17), and the insert material (17) comprises air, alveolar foam material, LDPE low-density polyethylene, water, polystyrene, acrylic acid, iodine contrast agent (c 9.5mg/ml) and Teflon.

6. The novel CT phantom for evaluating clinical image quality of TCM and IR algorithms according to claim 4, wherein: a testing module with high contrast resolution and low contrast detectability is added into the second layer module (15), a third layer module (16) is arranged on one side of the second layer module (15), and the thicknesses of the third layer module (16), the second layer module (15) and the first layer module (14) are the same.

Technical Field

The invention relates to the technical field of CT (computed tomography) phantoms, in particular to a novel CT phantom for evaluating clinical image quality of TCM (TCM) and IR (infrared) algorithms.

Background

X-ray Computed Tomography (CT) is widely used in clinical diagnosis due to its characteristics of fast imaging, clear image, and the like, and in order to obtain a high-resolution and low-noise image, CT equipment technology is rapidly developed, thereby bringing a risk of radiation exposure.

But currently there is no phantom-based method to properly evaluate the image quality of CT in IR reconstruction; moreover, TCM performance has been neglected by current medical and physical evaluation specifications due to the lack of independent evaluation methods. Some current motifs available for evaluating TCM performance are either composed of several discrete parts or are composed of a homogeneous material; but cannot evaluate other performance indicators than body type-discrete noise functions. In addition, contrast and resolution are also affected by body type, but currently available CT phantoms cannot be measured and evaluated.

CT performance is typically measured using physical phantoms whose purpose is to quantify radiation dose and image quality indices, and currently, there are a range of phantoms mainly used for image noise, spatial resolution, CT value (Hounsfield Unit, HU) accuracy, collimation, and low contrast detectability, and some existing CT quality control phantoms mainly include: the ACR series CT image quality certification die body of the American radiology society is used for the certification test of the ACR CT; the Catphan series die body is used for the quality control test of CT; and various quality control test mold bodies provided by manufacturers. A ctdi (CT dose index) phantom for CT dose testing and a TCM test phantom made up of a series of discrete modules. Although these phantoms have proved to be of great significance in CT quality control testing, they have not been able to perform the common key technical performance tests of modern CT systems: for example, image quality performance is related to body size, tube current modulation, and iterative reconstruction.

Internationally, few documents are researched for performance index tests brought by new technologies such as AEC, TCM and IR. Amy k.hara et al performed relevant studies on methods for evaluating image noise, low-contrast detectability, image quality, and spatial resolution of adaptive statistical iterative reconstruction algorithms in low-dose CT systems based on ACR phantoms (gamma 464). Nicholas Keat et al used tapered acrylic AEC phantom mounts on Catphon phantom tanks to study the effect on patient size and Z-axis orientation of the AEC system. The AEC phantom is continuously sized from less than the infant's abdominal size to greater than the adult's abdominal size and has an elliptical cross-sectional area. Stephen j, lokitz et al, partially studied the performance index of large-scale patient sizes using tube current modulation and low dose CT techniques in CT scans using homemade tiled AEC phantoms, Olav Christianson, MS et al, studied the differences in image quality in terms of low contrast to noise ratio (CNR), detectable noise index and spatial resolution using the FBP and IR algorithms using ACR CT phantoms, sebastin t, schindar et al, studied the effects of patient size on radiation dose and on image noise when MDCT was automatically tube current modulated in abdominal scans using the simulated female phantoms of three sizes (model: model 702, CIRS), however, there is no corresponding research on the effects of the new TCM technology and the IR algorithm on the body type-noise function and the modulation transfer function, and there is no research on the effects of other physical performance indexes in images of different body types of patients.

From the current research situation at home and abroad, few existing technologies aim at novel CT (computed tomography) technology, particularly AEC, TCM, IR (infrared emission computed tomography) and the like to evaluate the body type effect of a human body and the performance evaluation of the body type effect on the CT value accuracy, resolution and noise influence in clinical application. But there is no method for system evaluation of the body type-noise function, modulation transfer function and other performance indexes (such as contrast, etc.) brought by the new TCM technology and the IR algorithm. At present, there is no unified model body available for image quality evaluation in clinical application of TCM technology and IR algorithm.

Disclosure of Invention

The sizes of six main modules in the invention are determined according to the abdomen size data of reference people of different ages of AAPM Report No.220 so as to evaluate the influence of human body shape effect on CT value precision, resolution and noise, meanwhile, a body type-noise function and a modulation transfer function can be obtained, in order to reduce the edge effect, conical homogeneous mold bodies are adopted for transition among the mold bodies with different sizes, tungsten filaments for testing the precision deviation of positioning light and the thickness deviation are embedded into the first layer of each main module, the novel CT mold body better combines physical quality control with clinical quality control, and not only can the performance evaluation test of the novel CT technology TCM, IR algorithm and the like for reducing the CT dosage be realized, but also the physical quality control can be carried out on CT equipment, thereby overcoming the defects in the prior art, and a novel CT phantom for evaluating clinical image quality of TCM and IR algorithms is provided.

In order to achieve the purpose, the invention adopts the following technical scheme: a novel CT (computed tomography) die body for evaluating clinical image quality of TCM and IR (TCM and infrared) algorithms comprises a die body, wherein one end of the die body is provided with a first main module, the other end of the die body is provided with a sixth main module, one side of the first main module is provided with a second main module, one side of the second main module is provided with a third main module, one side of the third main module is provided with a fourth main module, and one side of the fourth main module is provided with a fifth main module;

the die body is made of polyethylene materials, the diameters of the first main module, the second main module, the third main module, the fourth main module, the fifth main module and the sixth main module are sequentially reduced, a first connecting module, a second connecting module, a third connecting module, a fourth connecting module and a fifth connecting module are sequentially arranged at the joints of the first main module, the second main module, the third main module, the fourth main module, the fifth main module and the sixth main module, and the first connecting module, the second connecting module, the third connecting module, the fourth connecting module and the fifth connecting module are all in conical homogeneous die body transition.

Preferably, a physical quality control analysis module is integrated into each main module of the die body.

Preferably, a fixing rod is installed in the center of the die body, and one end of the fixing rod penetrates through the interiors of the first main module, the second main module, the third main module, the fourth main module, the fifth main module and the sixth main module.

Preferably, the first layer module, the second layer module, the third layer module, the fourth layer module, the fifth layer module and the sixth layer module are arranged inside the first main module, the second layer module and the test module for positioning light precision deviation and reconstruction layer thickness deviation are added inside the first layer module.

Preferably, the first layer module is internally provided with an insert material comprising air, alveolar foam, LDPE, water, polystyrene, acrylic acid, iodine contrast agent (c 9.5mg/ml) and teflon.

Preferably, a testing module with high contrast resolution and low contrast detectability is added in the second layer module, a third layer module is arranged on one side of the second layer module, and the third layer module, the second layer module and the first layer module are all the same in thickness.

Compared with the prior art, the invention has the advantages and positive effects that:

compare with current CT matter accuse die body, not only considered the influence of size factor to novel technique in the aspect of clinical performance to obtain size-noise function, modulation transfer function, in order to reduce marginal effect, will adopt the even die body of toper to pass through between the die body of unidimensional, and cover more material plug-ins that correspond with human tissue HU value to the linear test module of CT value, still merged into the test module of physics matter accuse simultaneously: embedding tungsten filaments for testing the precision deviation and the layer thickness deviation of the positioning light into the first layer of each main module; vertically adding a tungsten wire for testing MTF; the second layer is mainly a test module with high contrast resolution and low contrast detectability; the third layer is a testing module for uniformity, noise and artifacts, the novel CT die body combines physical quality control with clinical quality control better, and can evaluate and test the performances of a CT new technology TCM, an IR algorithm and the like for reducing CT dosage and perform physical quality control on CT equipment, so that the problem that the existing die body cannot perform clinical quality control is solved.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a cross-sectional view of the present invention.

Fig. 3 is a cross-sectional view of a first layer module of the present invention.

Fig. 4 is a cross-sectional view of a second layer module of the present invention.

The reference signs are: 1. a mold body main body; 2. a first main module; 3. a second main module; 4. a third main module; 5. a fourth main module; 6. a fifth main module; 7. a main module six; 8. a fixing rod; 9. a first connecting module; 10. a second connecting module; 11. a third connecting module; 12. connecting the module IV; 13. a fifth connecting module; 14. a first layer module; 15. a second layer module; 16. a third layer of modules; 17. and (3) an insert material.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be further described with reference to the accompanying drawings and examples. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments of the present disclosure.

An embodiment of the invention provides a novel CT phantom for evaluating clinical image quality of TCM and IR algorithms, as shown in fig. 1 to 4, including a phantom body 1, one end of the phantom body 1 is provided with a first main module 2, and the other end of the phantom body 1 is provided with a sixth main module 7, one side of the first main module 2 is provided with a second main module 3, one side of the second main module 3 is provided with a third main module 4, one side of the third main module 4 is provided with a fourth main module 5, and one side of the fourth main module 5 is provided with a fifth main module 6;

the die body 1 is made of polyethylene materials, the diameters of the first main module 2, the second main module 3, the third main module 4, the fourth main module 5, the fifth main module 6 and the sixth main module 7 are sequentially reduced, a first connecting module 9, a second connecting module 10, a third connecting module 11, a fourth connecting module 12 and a fifth connecting module 13 are sequentially arranged at the connecting position of the first main module 2, the second main module 3, the third main module 4, the fourth main module 5, the fifth main module 6 and the sixth main module 7, and the first connecting module 9, the second connecting module 10, the third connecting module 11, the fourth connecting module 12 and the fifth connecting module 13 are all in conical homogeneous die body transition.

As shown in fig. 2, a physical quality control analysis module is incorporated into the die body 1.

As shown in fig. 2, a fixing rod 8 is installed at the center of the die body 1, and one end of the fixing rod 8 passes through the interiors of the first main module 2, the second main module 3, the third main module 4, the fourth main module 5, the fifth main module 6 and the sixth main module 7.

As shown in fig. 2, a first layer module 14 is arranged inside each of the first main module 2, the second main module 3, the third main module 4, the fourth main module 5, the fifth main module 6 and the sixth main module 7, a second layer module 15 is arranged on one side of the first layer module 14, and a test module for positioning light precision deviation and reconstruction layer thickness deviation is added inside the first layer module 14.

As shown in fig. 2, the first layer module 14 is provided with an insert material 17 inside, and the insert material 17 includes air, alveolar foam, LDPE low density polyethylene, water, polystyrene, acrylic, iodine contrast agent c ═ 9.5mg/ml, and teflon.

As shown in fig. 4, a testing module with high contrast resolution and low contrast detectability is added in the second layer module 15, and a third layer module 16 is arranged on one side of the second layer module 15, and the thickness of the third layer module 16, the thickness of the second layer module 15 and the thickness of the first layer module 14 are the same.

As shown in fig. 1 to 4, the implementation scenario specifically includes: selecting a polyethylene material as a main body part material of the die body main body 1, and selecting an insert material 17 in the die body main body 1 according to HU values of different parts of a human body for analyzing contrast and CT value linear indexes of the different parts of the human body; in addition, a physical quality control analysis module is integrated, a first connecting module 9, a second connecting module 10, a third connecting module 11, a fourth connecting module 12 and a fifth connecting module 13 adopt a conical homogeneous phantom for transition to obtain a body type-noise function and a modulation transfer function, so that the edge effect is reduced, a first main module 2, a second main module 3, a third main module 4, a fourth main module 5, a fifth main module 6 and a sixth main module 7 are connected by a fixing rod 8 and are convenient to carry, the sizes of the first main module 2, the second main module 3, the third main module 4, the fourth main module 5, the fifth main module 6 and the sixth main module 7 are determined according to the abdomen size data of reference persons in different age groups of AAPM Report No.220, each main module is composed of three layers, the plug-in material 17 of a first layer module 14 of each main module is selected according to HU values of different parts of a human body, and is used for linear analysis of contrast performance indexes and CT values of different parts of the human body, a CT value linear testing module (HU values of different parts of a human body correspond to simulation materials to manufacture plug-ins); a module for testing the precision deviation of the positioning light and the layer thickness deviation (two groups of 23-degree metal wire oblique lines are embedded, the projection length is 50mm, and the module is not contained in a 130mm main body part); modulation transfer function MTF test module (tungsten filament 0.05mm in diameter, perpendicular to the imaging plane), selected insert material 17: air, alveolar foam material, LDPE low-density polyethylene, water, polystyrene, acrylic acid, iodine contrast agent (c is 9.5mg/ml) and Teflon, wherein a test module for positioning light precision deviation and reconstruction layer thickness deviation is added in the module, a second layer module 15 of each master die body is added with a test module for high contrast resolution and low contrast detectability, the low contrast detectability test module (two groups of inner and outer low-density pore diameter structures: the contrast of an inner layer pore array is 0.3%, 0.5% and 1.0%, the diameter is 3/5/7/9mm, the contrast of an outer layer pore array is 0.3%, 0.5% and 1.0%, and the diameter is 2/3/4/5/6/7/8/9/15mm) and the spatial resolution test module (30 groups of high-density line pair structures: the interval and the width of line pairs are the same, and the interval and the width of the line pairs are calculated by the formula lp/cm (1/2a), a unit cm, and a line pair length of 4 mm); the third layer module 16 of each main body part is homogeneous polyethylene (used for testing noise and artifacts), and the technical scheme provided by the invention shows that the invention adopts the scheme of combining multifunctional testing modules; in order to reduce the edge effect, conical homogeneous die bodies are adopted for transition among die bodies with different sizes; the main modules 2, 3, 4, 5, 6 and 7 with different sizes are connected in the form of fixed bars 8,

TABLE 1 effective size of main body part of novel CT phantom

Table 2 CT value linear material selection

Serial number	Name of Material	CT value range (HU)	Corresponding to human tissue/other remarks
				1	Air (a)	-1046:-986	Alveolus
				2	Alveolar foam #7112	-952:-810	Lung tissue
3	Low Density Polyethylene (LDPE)	-121:-87	Fat
				4	Water (W)	-7:7	Body fluid
5	Polystyrene	-65:-29	/
				6	Acrylic acid	92:137	/
7	Iodine contrast agent (c ═ 9.5mg/ml)	270:300	Enhanced CT
				8	Teflon	941:1060	Bone tissue

The working principle of the invention is as follows:

referring to the attached drawings 1-4 of the specification, compared with the existing CT quality control mold body, the novel CT test mold body provided by the invention not only considers the influence of the body type-noise function, the modulation transfer function and the body type factor on the clinical performance of the novel technology, but also covers more material plug-ins corresponding to the HU value of the human tissue aiming at the linear test module of the CT value, and simultaneously integrates the test module of physical quality control: embedding tungsten filaments for testing the precision deviation and the layer thickness deviation of the positioning light into the first layer of each main module; vertically adding a tungsten wire for testing MTF; the second layer is mainly a test module with high contrast resolution and low contrast detectability; the third layer is a testing module for uniformity, noise and artifacts, the novel CT die body combines physical quality control with clinical quality control better, and can evaluate and test the performances of a CT new technology TCM, an IR algorithm and the like for reducing CT dosage and perform physical quality control on CT equipment, so that the problem that the existing die body cannot perform clinical quality control is solved.

The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.