CN112862772A

CN112862772A - Image quality evaluation method, PET-MR system, electronic device, and storage medium

Info

Publication number: CN112862772A
Application number: CN202110128593.XA
Authority: CN
Inventors: 马润霞; 吉子军
Original assignee: Shanghai United Imaging Healthcare Co Ltd
Current assignee: Shanghai United Imaging Healthcare Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-05-28
Anticipated expiration: 2041-01-29
Also published as: CN112862772B

Abstract

The present application relates to an image quality evaluation method, a PET-MR system, an electronic apparatus, and a storage medium, wherein the image quality evaluation method includes: acquiring a PET-CT image scanning protocol, acquiring scanning data according to the PET-CT image scanning protocol, and acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and a CT image in a PET-CT system; performing attenuation correction on PET data in the PET-MR system according to the mapping relation; carrying out image reconstruction according to the attenuation corrected PET data to obtain a reconstructed image; and carrying out image quality evaluation on the PET-MR system according to the reconstructed image. By the method and the device, the problem that in the related art, due to the fact that the magnetic resonance signals with different tissue densities cannot be obtained, the accuracy is low when attenuation correction is carried out on the image is solved, and the accuracy of the attenuation correction in the PET-MR system is improved.

Description

Image quality evaluation method, PET-MR system, electronic device, and storage medium

Technical Field

The present application relates to the field of medical device technology, and in particular to an image quality assessment method, a PET-MR system, an electronic device, and a storage medium.

Background

The multi-modality medical imaging scanning system is often influenced by various factors during imaging, among which, the attenuation effect is also an important factor influencing the imaging quality, and besides the attenuation causes counting loss and inaccurate quantification, the attenuation can also cause image non-uniformity and distortion phenomena. Therefore, in the whole simulation test process, a reconstruction algorithm is needed for attenuation correction.

In the related art, the attenuation correction only considers a liquid-filled phantom, because the liquid can provide a sufficient magnetic resonance signal. However, since materials such as glass and plastic cannot be detected by the magnetic resonance signal, quantification of attenuation correction cannot be achieved for phantom filled with glass and plastic. The attenuation correction can also be realized based on magnetic resonance image segmentation, and specifically, the magnetic resonance image is segmented into 4 regions with different attenuation coefficients, including air, fat, lung and soft tissue, by using a Three-dimensional Multi-echo Three-dimensional volume interpolation water-fat separation fast spoiling (referred to as Dixon-VIBE) sequence and a Dixon water-fat separation algorithm. However, this method cannot obtain signals of dense bone tissue from the magnetic resonance image, and the bone tissue attenuates radiation signals most seriously, and has the greatest influence on the imaging quality of the medical imaging scanner.

At present, no effective solution is provided for the problem of low precision in attenuation correction of images caused by the fact that magnetic resonance signals with different tissue densities cannot be obtained in the related technology.

Disclosure of Invention

The embodiment of the application provides an image quality evaluation method, a PET-MR system, an electronic device and a storage medium, so as to at least solve the problem of low precision when attenuation correction is carried out on an image due to the fact that magnetic resonance signals with different tissue densities cannot be obtained in the related art.

In a first aspect, an embodiment of the present application provides an image quality assessment method, including:

acquiring a PET-CT image scanning protocol, and acquiring scanning data according to the PET-CT image scanning protocol;

acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and a CT image in a PET-CT system;

attenuation correction is carried out on the PET data in the PET-MR system according to the mapping relation;

carrying out image reconstruction according to the attenuation corrected PET data to obtain a reconstructed image;

and carrying out image quality evaluation on the PET-MR system according to the reconstructed image.

In some embodiments, the obtaining a mapping from the scan data comprises:

acquiring CT data and PET data, and reconstructing a CT image according to the CT data;

and acquiring a mapping relation according to the PET data and the CT image.

In some of these embodiments, the acquiring a mapping from the PET data and CT images comprises:

obtaining attenuation information according to the CT image;

acquiring the position corresponding relation between the die body and the PET-CT system according to the position information of the die body in the PET-CT system;

and obtaining the mapping relation according to the attenuation information and the position corresponding relation.

In some of these embodiments, the acquiring a PET-CT image scan protocol according to which scan data is acquired comprises:

placing the die body at a preset position of a scanning bed of a PET-CT system through a tool, wherein the preset position is determined according to an imaging visual field of the PET-CT system;

and acquiring a scanning protocol, and scanning the die body according to the scanning protocol to acquire the scanning data.

In some embodiments, after the phantom is placed in a preset position on a scanning bed of the PET-CT system by the tool, the method comprises:

acquiring a deviation value between the actual position of the die body and the preset position;

if the deviation value is larger than a preset precision threshold value, correcting the actual position of the phantom according to the position mark on the phantom until the deviation value is smaller than or equal to the preset precision threshold value so as to register the CT image and the PET image acquired by the PET-CT system.

In some embodiments, after the phantom is placed in the preset position of the scanning bed of the PET-CT system by the tool, the method further comprises:

acquiring a CT image and a PET image of a PET-CT system, and registering the CT image and the PET image;

and correcting the actual position of the die body according to the registration result until the deviation value between the actual position of the die body and the preset position is less than or equal to a preset precision threshold.

In some of these embodiments, prior to said image quality assessment of the PET-MR system from said reconstructed image, the method further comprises:

acquiring an image quality evaluation instruction, acquiring an acquisition protocol according to the image quality evaluation instruction, and acquiring the mapping relation if judging that the image quality evaluation is performed on the PET-MR system by adopting a preset standard according to the acquisition protocol.

In a second aspect, an embodiment of the present application provides a PET-MR system, including an acquisition module, a correction module, a reconstruction module, and an evaluation module;

the acquisition module is used for acquiring a PET-CT image scanning protocol and acquiring scanning data according to the PET-CT image scanning protocol; acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and a CT image in a PET-CT system;

the correction module is used for carrying out attenuation correction on the PET data in the PET-MR system according to the mapping relation;

the reconstruction module is used for reconstructing an image according to the attenuation-corrected PET data to obtain a reconstructed image;

the evaluation module is used for carrying out image quality evaluation on the PET-MR system according to the reconstructed image.

In a third aspect, an embodiment of the present application provides an electronic apparatus, which includes a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor, when executing the computer program, implements the image quality assessment method according to the first aspect.

In a fourth aspect, the present application provides a storage medium, on which a computer program is stored, which when executed by a processor implements the image quality assessment method as described in the first aspect above.

Compared with the prior art, the image quality evaluation method provided by the embodiment of the application acquires the PET-CT image scanning protocol, acquires the scanning data according to the PET-CT image scanning protocol, and acquires the mapping relation according to the scanning data, wherein the mapping relation is the relation between the PET data and the CT image in the PET-CT system; performing attenuation correction on PET data in the PET-MR system according to the mapping relation; carrying out image reconstruction according to the attenuation corrected PET data to obtain a reconstructed image; the method and the device have the advantages that the image quality of the PET-MR system is evaluated according to the reconstructed image, the problem of low precision in attenuation correction of the image due to the fact that magnetic resonance signals with different tissue densities cannot be obtained in the related technology is solved, and the precision of the attenuation correction in the PET-MR system is improved.

The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of the application.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

FIG. 1 is a schematic view of a mold body according to an embodiment of the present application;

FIG. 2 is a flow chart of an image quality assessment method according to an embodiment of the present application;

FIG. 3 is a flowchart of a method for obtaining a mapping relationship according to an embodiment of the present application;

fig. 4 is a block diagram of a hardware structure of a terminal of the image quality evaluation method according to the embodiment of the present application;

FIG. 5 is a block diagram of a PET-MR system according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided in the present application without any inventive step are within the scope of protection of the present application. Moreover, it should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of ordinary skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments without conflict.

Unless defined otherwise, technical or scientific terms referred to herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar words throughout this application are not to be construed as limiting in number, and may refer to the singular or the plural. The present application is directed to the use of the terms "including," "comprising," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Reference herein to "a plurality" means greater than or equal to two. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.

The image quality evaluation method provided by the application can be applied to the process of detecting the performance of a Positron Emission Tomography (PET) system by adopting the National Electrical Manufacturers Association (NEMA) standard. Specifically, in the process of performing performance detection of the PET apparatus using the NEMA standard, there is an index of Image Quality assessment (Image Quality), and in the detection of the PET-MR system, Image Quality of the PET apparatus is also required, where MR is Magnetic Resonance (Magnetic Resonance). Generally, a PET device is affected by various factors during imaging, and for all imaging systems including the PET device, imaging standard conditions need to be formed under the condition of simulating clinic so as to compare the image quality of different PET devices. The NEMA standard defines a fixed device phantom (phantom) for Image Quality metrics to evaluate Image Quality of PET equipment.

To generate an image simulating the whole body, hot and cold spheres of different diameters are placed in the phantom, the image quality is evaluated based on the image contrast and background rate of change of the hot and cold spheres, and the accuracy of the correction of attenuation and scatter is given at the same time. Wherein, the cold ball is a ball without activity injected with water, and the hot ball is a radiation source injected with N times of background activity concentration. The radiation source is injected into the line source of the phantom to generate an effective activity "concentration" equal to the background activity concentration, and if the background activity is low, the corresponding line source activity should be reduced.

FIG. 1 is a schematic view of a phantom according to an embodiment of the present application, as shown in FIG. 1, white spheres having diameters of 28mm and 37mm, respectively, water is injected as cold spheres, black spheres having diameters of 10mm, 13mm, 17mm, and 22mm, respectively, are injected as hot spheres, and a radiation source is injected as a hot sphere. The oblique line shaded area simulates the lung, and is formed by inserting a cylinder into the center of the die body, wherein the cylinder is filled with a substance with a small atomic number, the outer diameter of the cylinder is about 50mm, the thickness of the cylinder is less than 4mm, and the cylinder is filled with the whole die body in the axial direction. The grid fill area serves as a background area.

In the process of image quality evaluation, attenuation correction needs to be performed on the image. In the related art, MR-based attenuation correction only takes into account liquid-filled phantoms, since liquids can provide sufficient MR signals. However, if there are fills of glass and plastic material in the phantom, quantitative attenuation correction cannot be achieved because these fills cannot be detected by the MR signal. Further, in general, the PET-MR attenuation correction algorithm is implemented based on a PET-MR image segmentation method, which utilizes a fast three-dimensional Dixon VIBE sequence and a Dixon water-fat separation algorithm to segment the PET-MR image into 4 regions with different attenuation coefficients, including air, fat, lung and soft tissue. However, the method cannot obtain signals of dense bone tissues from the PET-MR images, and the PET signals are most severely attenuated by the bone tissues, so that the influence on the image quality is the greatest.

The present embodiment provides an image quality evaluation method, and fig. 2 is a flowchart of an image quality evaluation method according to an embodiment of the present application, as shown in fig. 2, the method includes the following steps:

step S210, acquiring a PET-CT image scanning protocol, acquiring scanning data according to the PET-CT image scanning protocol, and acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and a CT image in a PET-CT system.

In this embodiment, the scan is performed in the PET-CT system before the image quality evaluation of the PET-MR system. The CT is Computed Tomography (CT), in which a layer of a certain thickness of a scanned region is scanned by using precisely collimated X-rays, the X-rays transmitted through the layer are received by a detector, and converted into visible light, and then converted into electrical signals by a photoelectric converter, and then converted into digital signals by an analog/digital converter for processing.

The PET-CT image scanning protocol is the stipulation of PET-CT on scanning parameters in the scanning process, including parameters of scanning position, duration and the like. After the scan protocol is determined, a PET-CT system scans a scan object to acquire scan data including PET data and CT data, where the PET data is scan data acquired by a detector of a PET device during a scan process, the CT data is data acquired by CT scan, a CT image can be obtained based on the CT data, and then a continuous u-map (attenuation information) can be obtained from the CT image, where the u-map includes a correspondence relationship between the PET data and the CT image. Because the relative position of the PET device and the CT device in the PET-CT system is fixed, the obtained CT image and the PET data have corresponding relation.

And S220, performing attenuation correction on the PET data in the PET-MR system according to the mapping relation.

In the process of CT scanning, different regions in the scanned object have different densities, so that the different regions have different absorption of X-rays, and therefore, the CT image obtained by CT scanning can obtain attenuation information of the different regions, and the attenuation information has a mapping relation with PET data in a PET-CT system.

On the other hand, the PET device in the PET-MR system has the same structure as the PET device in the PET-CT system, and the PET device and the MR device in the PET-MR system also have a correspondence relationship. In the case of scanning the same scanning phantom, the attenuation information obtained by the PET-CT can be used for attenuation correction of PET data of the PET-MR system based on the mapping relation.

And step S230, carrying out image reconstruction according to the attenuation corrected PET data to obtain a reconstructed image.

Before image reconstruction of the PET data, attenuation correction needs to be performed on the PET data to obtain more accurate PET data, and on the basis, the obtained reconstructed image can reflect the conditions of different regions in the scanned object.

In step S240, the PET-MR system is subjected to image quality evaluation according to the reconstructed image, wherein the evaluation of the image quality may be performed according to the signal-to-noise ratio of the reconstructed image.

Through the steps S210 to S240, the PET-CT system obtains the mapping relationship, and since the mapping relationship includes the attenuation information obtained through CT scanning, and the accuracy of the attenuation information is higher than the accuracy of attenuation correction performed by a liquid-filled phantom in the related art and the accuracy of attenuation correction performed by segmenting the PET-MR image, the accuracy of attenuation correction performed on the PET data in the PET-MR system based on the attenuation information is higher, so that the problem of lower accuracy in attenuation correction performed on the image due to the inability to obtain magnetic resonance signals of different tissue densities in the related art is solved, and the accuracy of attenuation correction in the PET-MR system is improved.

In some of these embodiments, obtaining the mapping from the scan data comprises: after the scanning protocol is determined, scanning a phantom fixed on a scanning bed of a PET-CT system so as to acquire CT data and PET data; and then, reconstructing a CT image according to the CT data, wherein a reconstruction algorithm can be set according to requirements, and because the same phantom is performed during CT scanning and PET scanning and the relative positions of PET equipment and CT equipment in a PET-CT system are fixed, pixels in the PET data and the CT image have a corresponding relation, and a mapping relation can be obtained according to the PET data and the CT image. In this embodiment, the accuracy of the mapping relationship can be improved by obtaining the mapping relationship based on the PET data and the CT data obtained after the PET-CT system scans the phantom.

In some embodiments, a method for obtaining a mapping relationship is further provided, and fig. 3 is a flowchart of a method for obtaining a mapping relationship according to an embodiment of the present application, as shown in fig. 3, the method includes the following steps:

step S310, attenuation information is obtained according to the CT image.

In the process of forming a CT image, each fault is divided into a plurality of cuboids with the same volume, called voxels, and the information obtained by CT scanning is calculated to obtain the X-ray attenuation coefficient or absorption coefficient of each voxel, so that the attenuation information can be obtained from the obtained CT image.

And S320, acquiring the position corresponding relation between the phantom and the PET-CT system according to the position information of the phantom in the PET-CT system.

Before scanning the mold body, the mold body may be placed on a scanning bed of the PET-CT system, and then according to geometric parameters of the mold body, such as information of length, width, diameter, thickness, and the like, in a coordinate system of the PET-CT system, position information of the mold body in the PET-CT system is obtained, including a start point coordinate, an end point coordinate, and a height coordinate of the mold body in a horizontal plane, so that a position corresponding relationship between the mold body and the PET-CT system may be obtained, where the position corresponding relationship is specifically a relative position between the mold body and the scanning bed of the PET-CT system. Preferably, the relative position can also be determined by a placing support of the die body.

And step S330, obtaining a mapping relation according to the attenuation information and the position corresponding relation.

The attenuation information is used for correcting PET data, and the position corresponding relation is used for ensuring that the relative positions of the die body and the PET equipment are consistent in the scanning process of different PET equipment.

Through the steps S310 to S330, in this embodiment, when the phantom is scanned, the position corresponding relationship between the phantom and the scanning bed of the PET-CT system is obtained, and the mapping relationship is obtained according to the position number corresponding relationship and the attenuation information in the CT image, so that the mapping relationship is more accurate, and the image quality evaluation of the PET-MR system is more accurate.

In some of these embodiments, the scan data is obtained by: the die body is placed at a preset position of a scanning bed of a PET-CT system through a tool, then a scanning protocol is obtained, CT scanning is carried out on the die body according to the scanning protocol, and scanning data are obtained. The tool is used for placing the die body, and comprises a fixing tool and a connecting tool, wherein the fixing tool is used for fixing the die body on a scanning bed, the connecting tool is used for connecting two PET mounting rings, when the die body is placed, the two connected PET mounting rings are sleeved on a transmitting coil, and then the positioning tool is used for carrying out axial positioning and radial positioning on the PET mounting rings and the transmitting coil. Further, the preset position is determined according to an imaging field of View (Angle of View) of the PET-CT system, and preferably, the preset position is located at the center of an Angle of View (Angle of View) of the PET-CT system, and since light rays at the center of the Angle of View are more sufficient, a better scanning effect can be obtained at the center of the Angle of View. The scanning protocol comprises parameters such as scanning positions, scanning time and the like, and is used for controlling the specific scanning process of the phantom body to obtain PET-CT image scanning data of different scanning positions. In the embodiment, the position of the die body is determined through the tool, so that the position of the die body is unchanged from the PET-CT system to the PET-MR system, and the attenuation correction precision is improved.

Further, after the phantom is placed at a preset position of a scanning bed of the PET-CT system through the tool, it is also required to determine whether the actual position of the phantom is located at the preset position.

One method is that a deviation value between the actual position and the preset position of the mold body is obtained, if the deviation value is larger than a preset precision threshold value, the actual position of the mold body is corrected according to a position mark on the mold body until the deviation value is smaller than or equal to the preset precision threshold value, and therefore the CT image and the PET image obtained by the PET-CT system are registered. The actual position of the die body can be obtained through sensor induction or captured by a camera, the preset precision threshold value can be set according to experience, and the suitable precision threshold value can be obtained through algorithm iterative calculation. The die body and the scanning bed can be marked in advance, and the die body is moved through the relative position of the marking points until the deviation value is smaller than a preset precision threshold value.

The other method comprises the steps of obtaining a CT image and a PET image of the PET-CT system, registering the CT image and the PET image, and correcting the actual position of the phantom according to a registration result until the deviation value between the actual position and the preset position of the phantom is smaller than or equal to a preset precision threshold. The CT image and the PET image are registered to obtain a registered image, and whether the deviation value between the actual position and the preset position is smaller than a preset precision threshold value or not can be judged according to the quality of the registered image, obviously, the smaller the deviation value is, the better the quality of the registered image is. The quality of the registered image can be determined by the signal-to-noise ratio, and the corresponding relation between the signal-to-noise ratio and the deviation value can be calibrated in advance. In this embodiment, the phantom may be directly placed at a position satisfying the preset accuracy threshold according to the registration result, or the phantom may be adjusted in position according to a preset step length, and image registration is performed after the step length is adjusted each time, so as to determine whether a deviation value between the actual position and the preset position of the phantom satisfies the preset accuracy threshold.

Because the die body is placed in the process, slight dislocation possibly exists between the actual position and the preset position, and the precision of the scanning data is reduced, the embodiment for determining the actual position of the die body can ensure that the die body is located at the preset position in the scanning process, reduce errors caused by position number deviation values, and improve the precision of PET data and CT data.

In some embodiments, after the mapping relationship is acquired, the mapping relationship is stored in a file format, and the mapping relationship file is configured into the PET-MR system when the PET-MR system is shipped. Before the image quality of the PET-MR system is evaluated according to the reconstructed image, an image quality evaluation instruction needs to be acquired, an acquisition protocol is acquired according to the image quality evaluation instruction, if the image quality of the PET-MR system is judged to be evaluated by adopting a preset standard according to the acquisition protocol, a mapping relation is acquired, then attenuation correction is carried out on PET data in the PET-MR system according to the mapping relation, the image reconstruction is carried out according to the PET data after the attenuation correction, a reconstructed image is acquired, and the image quality evaluation is carried out on the PET-MR system according to the reconstructed image. The preset standard in this embodiment may be NEMA IQ, for example, when a protocol key (protocol key) of the acquisition protocol is NEMA IQ, the mapping relationship stored in the PET-MR system is read, attenuation correction is performed on the PET data according to the mapping relationship, and finally the image quality of the PET-MR system is evaluated, otherwise, a set of u-map information data may be generated directly from the MR image and the attenuation correction is performed on the PET data when the image quality of the PET-MR system is evaluated. The quality assessment of the PET-MR system can be carried out, among other things, by the signal-to-noise ratio of the images. In the embodiment, the set mapping relation is not used for evaluating the image quality of the PET-MR, and the image quality can be intelligently selected according to a protocol key in an acquisition protocol, so that the scene adaptability is improved.

It should be noted that the steps illustrated in the above-described flow diagrams or in the flow diagrams of the figures may be performed in a computer system, such as a set of computer-executable instructions, and that, although a logical order is illustrated in the flow diagrams, in some cases, the steps illustrated or described may be performed in an order different than here.

The method embodiments provided in the present application may be executed in a terminal, a computer or a similar computing device. Taking the operation on the terminal as an example, fig. 4 is a hardware structure block diagram of the terminal of the image quality evaluation method according to the embodiment of the present application. As shown in fig. 4, the terminal 40 may include one or more (only one shown in fig. 4) processors 402 (the processor 402 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 404 for storing data, and optionally may also include a transmission device 406 for communication functions and an input-output device 408. It will be understood by those skilled in the art that the structure shown in fig. 4 is only an illustration and is not intended to limit the structure of the terminal. For example, terminal 40 may also include more or fewer components than shown in FIG. 4, or have a different configuration than shown in FIG. 4.

The memory 404 may be used to store a control program, for example, a software program and a module of application software, such as a control program corresponding to the image quality evaluation method in the embodiment of the present application, and the processor 402 executes various functional applications and data processing by running the control program stored in the memory 404, so as to implement the method described above. The memory 404 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 404 may further include memory located remotely from the processor 402, which may be connected to the terminal 40 via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The transmission device 406 is used to receive or transmit data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the terminal 40. In one example, the transmission device 406 includes a Network adapter (NIC) that can be connected to other Network devices through a base station to communicate with the internet. In one example, the transmitting device 406 may be a Radio Frequency (RF) module, which is used to communicate with the internet in a wireless manner.

The present embodiment further provides a PET-MR system, which is used to implement the above embodiments and preferred embodiments, and the description of the above embodiments is omitted. As used hereinafter, the terms "module," "unit," "subunit," and the like may implement a combination of software and/or hardware for a predetermined function. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated.

FIG. 5 is a block diagram of a PET-MR system according to an embodiment of the present application, and as shown in FIG. 5, the apparatus includes an acquisition module 51, a correction module 52, a reconstruction module 53 and an evaluation module 54; the acquisition module 51 is used for acquiring a PET-CT image scanning protocol and acquiring scanning data according to the PET-CT image scanning protocol; acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and a CT image in a PET-CT system; a correction module 52, configured to perform attenuation correction on the PET data in the PET-MR system according to the mapping relationship; a reconstruction module 53, configured to perform image reconstruction according to the attenuation-corrected PET data to obtain a reconstructed image; and an evaluation module 54 for performing image quality evaluation on the PET-MR system according to the reconstructed image.

In this embodiment, the obtaining module 51 of the PET-CT system obtains a mapping relationship, and since the mapping relationship includes attenuation information obtained by CT scanning, and the attenuation information is more accurate than attenuation information obtained by performing attenuation correction on a mold body filled with liquid in the related art and by segmenting an MR image to realize attenuation correction, the accuracy of attenuation correction performed on PET data in the PET-MR system by the correcting module 52 based on the attenuation information is higher, so that the problem of lower accuracy in performing attenuation correction on the image due to the fact that magnetic resonance signals of different tissue densities cannot be obtained in the related art is solved, and the accuracy of attenuation correction in the PET-MR system is improved.

The above modules may be functional modules or program modules, and may be implemented by software or hardware. For a module implemented by hardware, the modules may be located in the same processor; or the modules can be respectively positioned in different processors in any combination.

The present embodiment also provides an electronic device comprising a memory having a computer program stored therein and a processor configured to execute the computer program to perform the steps of any of the above method embodiments.

Optionally, the electronic apparatus may further include a transmission device and an input/output device, wherein the transmission device is connected to the processor, and the input/output device is connected to the processor.

Optionally, in this embodiment, the processor may be configured to execute the following steps by a computer program:

s1, acquiring a PET-CT image scanning protocol, and acquiring scanning data according to the PET-CT image scanning protocol;

s2, acquiring a mapping relation according to the scanning data, wherein the mapping relation is the relation between PET data and CT images in a PET-CT system;

s3, performing attenuation correction on the PET data in the PET-MR system according to the mapping relation;

s4, carrying out image reconstruction according to the attenuation corrected PET data to obtain a reconstructed image;

and S5, performing image quality evaluation on the PET-MR system according to the reconstructed image.

It should be noted that, for specific examples in this embodiment, reference may be made to examples described in the foregoing embodiments and optional implementations, and details of this embodiment are not described herein again.

In addition, in combination with the image quality method in the above embodiments, the embodiments of the present application may be implemented by providing a storage medium. The storage medium having stored thereon a computer program; the computer program, when executed by a processor, implements any of the image quality methods of the above embodiments.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An image quality evaluation method characterized by comprising:

2. The image quality evaluation method according to claim 1, wherein the acquiring a mapping relation from the scan data includes:

and acquiring a mapping relation according to the PET data and the CT image.

3. The image quality assessment method according to claim 2, wherein said acquiring a mapping from said PET data and CT image comprises:

obtaining attenuation information according to the CT image;

4. The image quality assessment method of claim 1, wherein said acquiring a PET-CT image scan protocol, according to which acquiring scan data comprises:

5. The image quality evaluation method according to claim 4, wherein after the phantom is placed at a preset position of a scanning bed of the PET-CT system by a tool, the method comprises:

6. The image quality evaluation method of claim 4, wherein after the phantom is placed at a preset position of a scanning bed of the PET-CT system by a tool, the method further comprises:

7. The image quality assessment method according to claim 1, wherein before said image quality assessment of a PET-MR system from said reconstructed image, said method further comprises:

8. A PET-MR system comprising an acquisition module, a correction module, a reconstruction module and an evaluation module;

9. An electronic device comprising a memory and a processor, wherein the memory has stored therein a computer program, and the processor is configured to execute the computer program to perform the image quality assessment method according to any one of claims 1 to 7.

10. A storage medium, in which a computer program is stored, wherein the computer program is arranged to execute the image quality assessment method according to any one of claims 1 to 7 when running.