Internal target area delineation method, device, equipment and medium based on 4D magnetic resonance imaging

Abstract

The present application relates to the technical field of internal target area delineation based on 4D magnetic resonance imaging, and discloses a method, apparatus, device, and medium for internal target area delineation based on 4D magnetic resonance imaging. The method comprises: obtaining a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image; determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image; determining a target scan duration based on the first probability distribution and each second probability distribution; performing a 4D magnetic resonance scan on a target object based on the target scan duration, obtaining a target nuclear magnetic resonance image corresponding to the target scan duration, and performing internal target area delineation based on the target nuclear magnetic resonance image. The method can determine an appropriate target scan duration, shorten the 4D magnetic resonance scan duration of the target object, and improve the accuracy of internal target area delineation.

Description

Technical Field

[0001] The present invention relates to the technical field of internal target area delineation based on 4D magnetic resonance imaging, and in particular to a method, device, equipment and medium for internal target area delineation based on 4D magnetic resonance imaging. Background Art

[0002] Treatment planning (TP) based on the motion probability density function (PDF) is an evolving approach to managing tumor motion. This approach requires measuring the PDF of the moving target tumor to delineate the internal target volume (ITV) for reliable and repeatable TP. However, due to the inability of single-slice dynamic magnetic resonance imaging (MRI) to capture the entire tumor volume and the impracticality of long scanning times, the PDF of tumor motion estimation contains potential errors, significantly impacting the accuracy of ITV delineation. Summary of the Invention

[0003] Based on this, it is necessary to address the technical problem that the scanning time of magnetic resonance imaging in the existing technology is unreasonable, resulting in low accuracy of ITV delineation, and propose an internal target area delineation method, device, equipment and medium based on 4D magnetic resonance imaging.

[0004] In a first aspect, a method for delineating an internal target region based on 4D magnetic resonance imaging is provided, the method comprising: acquiring a first abdominal 4D magnetic resonance image and respective second abdominal 4D magnetic resonance images, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration;

[0005] Determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0006] determining a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration;

[0007] According to the target scanning time, a 4D magnetic resonance scan is performed on the target object to obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and an internal target area is delineated based on the target nuclear magnetic resonance image.

[0008] In a second aspect, a device for delineating an internal target region based on 4D magnetic resonance imaging is provided, the device comprising: an acquisition module for acquiring a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, and the first scan duration is greater than the second scan duration;

[0009] a first determining module, configured to determine a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and to determine each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0010] a second determining module, configured to determine a target scanning duration according to the first probability distribution and each of the second probability distributions;

[0011] The delineation module is used to perform a 4D magnetic resonance scan on the target object according to the target scanning time, obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and perform internal target area delineation based on the target nuclear magnetic resonance image.

[0012] In a third aspect, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the above-mentioned internal target area delineation method based on 4D magnetic resonance imaging are implemented.

[0013] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the internal target area delineation method based on 4D magnetic resonance imaging are implemented.

[0014] The present invention proposes a method for delineating an internal target region based on 4D magnetic resonance imaging, which obtains a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan based on a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan based on a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to the actual abdominal radiotherapy duration. Then, a first probability distribution is determined based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D magnetic resonance image. Then, a target scan duration is determined based on the first probability distribution and each second probability distribution, and the target scan duration is less than the actual abdominal radiotherapy duration. Finally, a 4D magnetic resonance scan is performed on the target object based on the target scan duration to obtain a target nuclear magnetic resonance image corresponding to the target scan duration, and internal target region delineation is performed based on the target nuclear magnetic resonance image. It can determine the appropriate target scanning time and perform 4D magnetic resonance scanning on the target object, thereby improving the accuracy of internal target area delineation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] in:

[0017] Figure 1 FIG2 is a diagram illustrating an application environment of an internal target region delineation method based on 4D magnetic resonance imaging in one embodiment;

[0018] Figure 2 is a flow chart of a method for delineating an internal target region based on 4D magnetic resonance imaging in one embodiment;

[0019] Figure 3 is a respiratory displacement histogram of abdominal organs in an internal target area delineation method based on 4D magnetic resonance imaging in one embodiment;

[0020] Figure 4 FIG1 is a schematic diagram of a liver motion PDF repeatability of an internal target delineation method based on 4D magnetic resonance imaging in one embodiment;

[0021] Figure 5 A schematic diagram of a liver motion PDF repeatability of a 4D magnetic resonance imaging-based internal target delineation method during fractionated radiotherapy in one embodiment;

[0022] Figure 6 FIG4 is a schematic diagram of a method for calculating tumor motion probability volume in an internal target delineation method based on 4D magnetic resonance imaging in one embodiment;

[0023] Figure 7 is a structural block diagram of an internal target area delineation device based on 4D magnetic resonance imaging in one embodiment;

[0024] Figure 8 is a structural block diagram of a computer device in one embodiment;

[0025] Figure 9 It is a structural block diagram of a computer device in another embodiment. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] The internal target area delineation method based on 4D magnetic resonance imaging provided by the embodiment of the present invention can be applied in the following aspects: Figure 1In an application environment, a client 110 communicates with a server 120 via a network. The server 120 can receive a first abdominal 4D MRI image and each second abdominal 4D MRI image through the client 110, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration. A first probability distribution is then determined based on a preset organ reference position and the first abdominal 4D MRI image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D MRI image. A target scan duration is then determined based on the first probability distribution and each second probability distribution, wherein the target scan duration is less than the actual abdominal radiotherapy duration. Finally, a 4D MRI scan is performed on a target object based on the target scan duration to obtain a target MRI image corresponding to the target scan duration, and internal target area delineation is performed based on the target MRI image. The present invention can determine an appropriate target scan duration and perform 4D magnetic resonance scanning on a target object, thereby improving the accuracy of internal target area delineation. The client 110 can be, but is not limited to, various personal computers, laptops, smartphones, tablet computers, and portable wearable devices. The server 120 can be implemented as a standalone server or a server cluster consisting of multiple servers. The present invention is described in detail below using specific embodiments.

[0028] See also Figure 2 As shown, Figure 2 A schematic flow chart of a method for delineating an internal target region based on 4D magnetic resonance imaging according to an embodiment of the present invention includes the following steps:

[0029] Step S101: Acquire a first abdominal 4D MRI image and each second abdominal 4D MRI image, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan according to a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan according to a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration;

[0030] Among them, the actual abdominal radiotherapy duration refers to the abdominal radiotherapy duration commonly used in current hospitals.

[0031] As an example, for the purpose of determining an optimal 4D-MRI scan duration for an abdominal radiotherapy plan, a first abdominal 4D MRI scan may be acquired using 4D MRI (4D-MRI) technology, with a sampling rate of one volume per second (56 slices) and a resolution of 2.2 x 2.2 x 4 mm per reconstructed voxel, of the abdomen of at least one subject while the subject is breathing freely. For example, the first abdominal 4D MRI scan acquires 720 seconds of 4D MRI for each subject at a sampling rate of one 3D volume per second (1 3D volume / second), resulting in a first scan duration of 720 seconds.

[0032] As another example, to simulate the radiotherapy fractionation process, the second scan duration can be 144 seconds. The subject is scanned with a 4D-MRI once every 30 minutes, for a total of five scans, thereby obtaining five second abdominal 4D magnetic resonance images of 144 seconds in duration.

[0033] Step S102: determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0034] Among them, the organ reference position refers to the reference position of the human organ, which can be pre-set manually. For example, the standard position of the human abdominal organ is manually drawn as a reference reference position. The human abdominal organs may include the liver, left kidney, right kidney and spleen, etc.

[0035] In one implementation, the steps of determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image, include:

[0036] Step S1021: constructing a first organ respiratory displacement histogram according to a preset organ reference position and the first abdominal 4D magnetic resonance imaging;

[0037] For example, for each image in the first abdominal 4D MRI, the organs in the image are rigidly registered to the organ reference position, thereby obtaining the displacement of the organ. For example, a first organ respiratory displacement histogram is constructed based on the displacement and the histogram. Figure 3 Shown is the first organ respiratory displacement histogram of the liver.

[0038] Step S1022: performing fitting according to the first organ respiratory displacement histogram to obtain a first probability distribution;

[0039] For example, a time-evolving organ position probability distribution is extracted from the first organ respiratory displacement histogram within a scanning time (t1). The organ position probability distribution is the first probability distribution, which is recorded as PDF1(δ, t1), where δ refers to the average respiratory displacement of the organ.

[0040] As an example, consider n images containing organ A. The displacement of organ A from a reference position in these n images is calculated, and the sum of the displacements is divided by n to obtain the average position. The average displacement of organ A due to organ respiration is the displacement from this average position to the reference position.

[0041] Step S1023: constructing a second organ respiratory displacement histogram according to the preset organ reference position and the second abdominal 4D magnetic resonance imaging;

[0042] For example, for each image in the second abdominal 4D MRI, organs in the image are rigidly registered to the organ reference position to obtain organ displacement. For example, a second organ respiratory displacement histogram is constructed based on the displacement and the histogram. Since there are multiple second abdominal 4D MRI images, multiple second organ respiratory displacement histograms are also constructed.

[0043] Step S1024: performing fitting according to the second organ respiratory displacement histogram to obtain a second probability distribution.

[0044] For example, by fitting the second organ respiratory displacement histogram within a scan time (t2), we extract a time-evolving organ position probability distribution. This organ position probability distribution is the second probability distribution, denoted as PDF2(δ, t2, f), where δ is the average organ respiratory displacement and f indicates the scan number. For example, PDF2(δ, t2, 1) represents the PDF corresponding to the first 4D MRI scan. Since there are multiple second organ respiratory displacement histograms, we fit each of them separately to obtain a second probability distribution.

[0045] Step S103: determining a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration;

[0046] The target scan time is the best or preferred scan time for the 4D magnetic resonance imaging scan. The target scan time can be obtained by analyzing the first probability distribution and each second probability distribution.

[0047] In one implementation, the step of determining the target scanning duration according to the first probability distribution and each of the second probability distributions includes:

[0048] Step S1031: determining a first PDF repeatability coefficient according to the first probability distribution and a preset PDF repeatability coefficient formula;

[0049] The PDF repeatability coefficient formula is defined as follows:

[0050]

[0051] Among them, δ is the average displacement of organ respiration, t is the scanning time, f represents the number of scans, PDF ref represents the real PDF, R(t) is the difference between PDF(δ,t,f) and PDF under different scanning time. ref The repetitive coefficient between . ∩ represents the intersection, Represents a union.

[0052] In one implementation, the step of determining a first PDF repeatability coefficient according to the first probability distribution and a preset PDF repeatability coefficient formula includes:

[0053] Step S10311: extracting a probability distribution corresponding to a preset third scanning duration from the first probability distribution as a third probability distribution;

[0054] For example, in the first probability distribution PDF1(δ, t1), t1 is 720 seconds, and the preset third scan duration can be 0 to 720 seconds. In a preferred implementation, the third scan duration is 720 seconds, and PDF1(δ, 720s) is used as the third probability distribution.

[0055] Step S10312: extracting respective probability distributions corresponding to a preset scan duration set from the first probability distribution as respective fourth probability distributions, wherein the scan duration set includes a plurality of different scan durations, and the third scan duration is greater than or equal to the longest scan duration in the scan duration set;

[0056] The preset scanning duration set includes a plurality of different scanning durations.

[0057] For example, the scanning durations in the scanning duration set are an arithmetic progression with a difference of 3, that is, the scanning durations are 3, 6, 9...720, and the fourth probability distributions are PDF1(δ,3s), PDF1(δ,6s), PDF1(δ,9s)...PDF1(δ,720s).

[0058] Step S10313: Calculate the PDF repeatability coefficients of the third probability distribution and each of the fourth probability distributions according to a preset PDF repeatability coefficient formula to obtain each first PDF repeatability coefficient.

[0059] Specifically, the third probability distribution is used as the PDF in the PDF repeatability coefficient formula ref , using the fourth probability distribution as PDF(δ, t, f) in the PDF repeatability coefficient formula, and then using the PDF repeatability coefficient formula to calculate, the first PDF repeatability coefficient can be obtained. It should be noted that since the first abdominal 4D MRI was obtained through a single 4D MRI scan, the f in PDF(δ, t, f) is always 1. Figure 4 The figure shows the PDF repeatability of liver motion of 8 subjects. The horizontal axis is the scanning time and the vertical axis is the first PDF repeatability coefficient. It can be seen that all subjects showed that the PDF repeatability first increased rapidly and then changed slowly to finally reach 1. There were obvious differences among different subjects.

[0060] Step S1032: determining a second PDF repeatability coefficient according to each of the second probability distributions and a preset PDF repeatability coefficient formula;

[0061] In this embodiment, the second PDF repeatability coefficient may be determined by using each of the second probability distributions and a preset PDF repeatability coefficient formula.

[0062] In one implementation, the step of determining the second PDF repeatability coefficient according to each of the second probability distributions and a preset PDF repeatability coefficient formula includes:

[0063] Step S10321: selecting one second probability distribution from each second probability distribution as the fifth probability distribution, and selecting the second probability distribution from each second probability distribution except the fifth probability distribution as the sixth probability distribution;

[0064] Step S10322: For each sixth probability distribution, extract the probability distributions corresponding to the preset scanning duration set from the sixth probability distribution as the seventh probability distributions;

[0065] Each sixth probability distribution is extracted separately to obtain the seventh probability distribution. For example, the preset scanning duration set may range from 0 to 144 seconds, and the seventh probability distribution may be PDF2(δ,3,2), PDF2(δ,6,2), PDF2(δ,9,2) ... PDF2(δ,144,2), PDF2(δ,3,3), PDF2(δ,6,3), PDF2(δ,9,3) ... PDF2(δ,144,3), etc.

[0066] Step S10323: Calculate the PDF repeatability coefficients of the fifth probability distribution and each of the seventh probability distributions according to a preset PDF repeatability coefficient formula to obtain each second PDF repeatability coefficient.

[0067] In this embodiment, the fifth probability distribution is used as the PDF in the PDF repeatability coefficient formula ref , taking the seventh probability distribution as PDF(δ,t,f) in the PDF repeatability coefficient formula, and then using the PDF repeatability coefficient formula to calculate, we can get each second PDF repeatability coefficient. Figure 5 As shown, the schematic diagram of the PDF repeatability of liver motion corresponding to four 4D magnetic resonance imaging scans, and all four scans of all subjects showed a rapid increase in PDF repeatability and then a stable change as the scanning time increased.

[0068] Step S1033: Determine a target scanning time according to the first PDF repeatability coefficient and the second PDF repeatability coefficient.

[0069] Specifically, the target scanning time may be obtained by analyzing the first PDF repeatability coefficient and the second PDF repeatability coefficient.

[0070] In a preferred implementation, the step of determining the target scanning time according to the first PDF repeatability coefficient and the second PDF repeatability coefficient includes:

[0071] Step S10331: performing fitting according to the first PDF repeatability coefficient, the first scanning time, and a preset fitting function to obtain a first fitting formula;

[0072] Since there are obvious differences in PDF repeatability between different subjects at different scanning times, in order to reduce the influence of individual differences and enhance the universality of scanning time determined based on 4DMR.

[0073] The first PDF repeatability coefficient is used as the ordinate and the scan duration is used as the abscissa. A preset fitting function is used to fit the first fitting formula for the scan time. The preset fitting function can be a power function. It should be noted that the inter-subject error is expressed as a standard deviation. If there are multiple subjects, the mean of the first PDF repeatability coefficients corresponding to each subject is used as the ordinate. The first fitting formula is as follows:

[0074]

[0075] Among them, a, b, c are coefficients, t is the scanning time, is the first PDF repeatability coefficient.

[0076] The coefficients and evaluation indicators are as follows:

[0077]

[0078] Step S10332: performing fitting according to the second PDF repeatability coefficient, the second scanning time, and a preset fitting function to obtain a second fitting formula;

[0079] For example, with the second PDF repeatability coefficient as the ordinate and the scanning time as the abscissa, a preset fitting function is used for fitting, and the fitting is the second fitting function of the scanning time, wherein the preset fitting function is an exponential function. The second fitting formula is as follows:

[0080] Among them, A0, A1, and A2 are coefficients, and t is the scanning time.

[0081] The coefficients and evaluation indicators are as follows:

[0082]

[0083] Step S10333: Determine the target scanning duration according to the first fitting formula and the second fitting formula.

[0084] For example, two scanning durations can be calculated respectively by the first fitting formula and the second fitting formula, and a target scanning duration is selected from these two scanning durations.

[0085] In a preferred implementation, the step of determining the target scanning duration according to the first fitting formula and the second fitting formula includes:

[0086] Step A: Calculating according to the first fitting formula and the preset first PDF reproducibility curve value to obtain a fourth scanning time;

[0087] For example, according to the first fitting formula The preset first PDF reproducibility curve value is 85%. The scanning time t corresponding to the liver, left kidney, right kidney and spleen is calculated respectively. The average scanning time t of the liver, left kidney, right kidney and spleen is calculated and used as the fourth scanning time.

[0088] Step B: performing calculation according to the second fitting formula and the preset second PDF reproducibility curve value to obtain a fifth scanning time;

[0089] For example, according to the second fitting formula The preset second PDF reproducibility curve value is 63%. Calculate the scan times t corresponding to the liver, left kidney, right kidney, and spleen respectively, and calculate the average scan time t according to the scan times t corresponding to the liver, left kidney, right kidney, and spleen respectively, and use the average scan time as the fifth scan time.

[0090] Step C: Determine the target scanning duration according to the fourth scanning duration and the fifth scanning duration.

[0091] For example, between the fourth scanning duration and the fifth scanning duration, the longest scanning duration is used as the target scanning duration.

[0092] Step S104: performing a 4D magnetic resonance scan on the target object according to the target scan duration, obtaining a target nuclear magnetic resonance image corresponding to the target scan duration, and delineating an internal target area based on the target nuclear magnetic resonance image.

[0093] In this embodiment, the target scanning duration is the scanning duration of a 4D magnetic resonance scan of the target object. After obtaining the target nuclear magnetic resonance image, the internal target area can be delineated based on the target nuclear magnetic resonance image.

[0094] As an example, the dynamic position probability, PP, is calculated by dividing the number of voxels occupied by the organ of interest in a time frame by the total number of time frames. j =(M1+...+M j )×100%÷j, where M j =1 or 0, j represents the time frame index. The organ motion probability volume PPV is defined as: PP j >j%,(PPV j,i％ ), where i is the threshold. As the amount of data collected by 4D MRI continues to increase, the statistical information of tumor movement is also dynamically updated, and the delineation of the target area gradually reaches a steady state. After recording all possible tumor movement ranges, the tumor's motion probability volume (PPV) can be calculated. PPV reflects the probability of occurrence of each location of the tumor and can be used to accurately quantify the movement range of the tumor. The final tumor motion probability volume (PPV) is calculated as follows Figure 6 After calculating the PPV, a threshold can be set to further define the inner target area, i.e., the area where the probability of tumor presence exceeds the threshold. The threshold can be determined based on clinical needs, and the range selected is between 50% and 90% for the area where the probability of tumor presence is greater than or equal to 50%.

[0095] The internal target region delineation method based on 4D MRI proposed in this embodiment obtains a first abdominal 4D MRI image and each second abdominal 4D MRI image, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a second scan duration, wherein the first scan duration is greater than the second scan duration. A first probability distribution is then determined based on a preset organ reference position and the first abdominal 4D MRI image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D MRI image. A target scan duration is then determined based on the first probability distribution and each second probability distribution. Finally, a 4D MRI scan is performed on the target object based on the target scan duration to obtain a target MRI image corresponding to the target scan duration, and internal target region delineation is performed based on the target MRI image. This method can determine an appropriate target scan duration, shorten the 4D MRI scan duration of the target object, and improve the accuracy of internal target region delineation.

[0096] See also Figure 7 As shown, in one embodiment, a device for delineating an internal target region based on 4D magnetic resonance imaging is provided, the device comprising:

[0097] an acquisition module 10, configured to acquire a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration;

[0098] a first determining module 20 for determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0099] A second determining module 30 is configured to determine a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration;

[0100] The delineation module 40 is configured to perform a 4D magnetic resonance scan on the target object according to the target scan duration, obtain a target MRI image corresponding to the target scan duration, and delineate the internal target area based on the target MRI image.

[0101] The internal target region delineation method based on 4D MRI proposed in this embodiment obtains a first abdominal 4D MRI image and each second abdominal 4D MRI image, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to the actual abdominal radiotherapy duration. A first probability distribution is then determined based on a preset organ reference position and the first abdominal 4D MRI image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D MRI image. A target scan duration is then determined based on the first probability distribution and each second probability distribution, wherein the target scan duration is less than the actual abdominal radiotherapy duration. Finally, a 4D MRI scan is performed on the target object based on the target scan duration to obtain a target MRI image corresponding to the target scan duration, and internal target region delineation is performed based on the target MRI image. It can determine the appropriate target scanning time, shorten the 4D magnetic resonance scanning time of the target object, and improve the accuracy of internal target area delineation.

[0102] In one embodiment, the first determining module 20 is further configured to: construct a first organ respiratory displacement histogram based on a preset organ reference position and the first abdominal 4D magnetic resonance imaging;

[0103] Performing fitting based on the respiratory displacement histogram of the first organ to obtain a first probability distribution;

[0104] constructing a second organ respiratory displacement histogram according to the preset organ reference position and the second abdominal 4D magnetic resonance imaging;

[0105] Fitting is performed according to the second organ respiratory displacement histogram to obtain a second probability distribution.

[0106] In one embodiment, the second determining module 20 is further configured to: determine a first PDF repeatability coefficient according to the first probability distribution and a preset PDF repeatability coefficient formula;

[0107] Determining a second PDF repeatability coefficient according to each of the second probability distributions and a preset PDF repeatability coefficient formula;

[0108] A target scanning time is determined according to the first PDF repeatability coefficient and the second PDF repeatability coefficient.

[0109] In one embodiment, the second determining module 20 is further configured to:

[0110] Extracting a probability distribution corresponding to a preset third scanning duration from the first probability distribution as a third probability distribution;

[0111] Extracting respective probability distributions corresponding to a preset scan duration set from the first probability distribution as respective fourth probability distributions, wherein the scan duration set includes a plurality of different scan durations, and the third scan duration is greater than or equal to the longest scan duration in the scan duration set;

[0112] According to a preset PDF repeatability coefficient formula, the PDF repeatability coefficients of the third probability distribution and each of the fourth probability distributions are calculated respectively to obtain each first PDF repeatability coefficient.

[0113] In one embodiment, the second determining module 20 is further configured to:

[0114] Selecting one second probability distribution from each second probability distribution as the fifth probability distribution, and selecting the second probability distributions other than the fifth probability distribution from each second probability distribution as the sixth probability distribution;

[0115] For each sixth probability distribution, extracting probability distributions corresponding to a preset scanning duration set from the sixth probability distribution as seventh probability distributions;

[0116] According to a preset PDF repeatability coefficient formula, the PDF repeatability coefficients of the fifth probability distribution and each of the seventh probability distributions are calculated respectively to obtain each second PDF repeatability coefficient.

[0117] In one embodiment, the second determining module 20 is further configured to: perform fitting according to the first PDF repeatability coefficient, the first scanning time, and a preset fitting function to obtain a first fitting formula;

[0118] Perform fitting according to the second PDF repeatability coefficient, the second scanning time, and a preset fitting function to obtain a second fitting formula;

[0119] A target scanning duration is determined according to the first fitting formula and the second fitting formula.

[0120] In one embodiment, the second determining module 20 is further configured to: calculate according to the first fitting formula and a preset first PDF reproducibility curve value to obtain a fourth scanning duration;

[0121] Calculating according to the second fitting formula and the preset second PDF reproducibility curve value to obtain a fifth scanning time;

[0122] The target scanning duration is determined according to the fourth scanning duration and the fifth scanning duration.

[0123] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 8 As shown. The computer device includes a processor, memory, network interface and database connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes non-volatile and / or volatile storage media and internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external client via a network connection. When the computer program is executed by the processor, it implements the functions or steps on the server side of a method for delineating an internal target area based on 4D magnetic resonance imaging.

[0124] In one embodiment, a computer device is provided. The computer device may be a client, and its internal structure diagram may be as follows: Figure 9 As shown. The computer device includes a processor, memory, network interface, display screen, and input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external server via a network connection. When executed by the processor, the computer program implements the functions or steps on the client side of a method for delineating an internal target area based on 4D magnetic resonance imaging.

[0125] In one embodiment, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the following steps are implemented:

[0126] Acquiring a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration;

[0127] Determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0128] determining a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration;

[0129] According to the target scanning time, a 4D magnetic resonance scan is performed on the target object to obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and an internal target area is delineated based on the target nuclear magnetic resonance image.

[0130] The internal target region delineation method based on 4D MRI proposed in this embodiment obtains a first abdominal 4D MRI image and each second abdominal 4D MRI image, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to the actual abdominal radiotherapy duration. A first probability distribution is then determined based on a preset organ reference position and the first abdominal 4D MRI image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D MRI image. A target scan duration is then determined based on the first probability distribution and each second probability distribution, wherein the target scan duration is less than the actual abdominal radiotherapy duration. Finally, a 4D MRI scan is performed on the target object based on the target scan duration to obtain a target MRI image corresponding to the target scan duration, and internal target region delineation is performed based on the target MRI image. It can determine the appropriate target scanning time, shorten the 4D magnetic resonance scanning time of the target object, and improve the accuracy of internal target area delineation.

[0131] In one embodiment, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0132] Acquiring a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, and the first scan duration is greater than the second scan duration;

[0133] Determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image;

[0134] determining a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration;

[0135] According to the target scanning time, a 4D magnetic resonance scan is performed on the target object to obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and an internal target area is delineated based on the target nuclear magnetic resonance image.

[0136] The internal target region delineation method based on 4D MRI proposed in this embodiment obtains a first abdominal 4D MRI image and each second abdominal 4D MRI image, wherein the first abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a first scan duration, and the second abdominal 4D MRI image is obtained by performing a 4D MRI scan based on a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to the actual abdominal radiotherapy duration. A first probability distribution is then determined based on a preset organ reference position and the first abdominal 4D MRI image, and each second probability distribution is determined based on the preset organ reference position and each second abdominal 4D MRI image. A target scan duration is then determined based on the first probability distribution and each second probability distribution, wherein the target scan duration is less than the actual abdominal radiotherapy duration. Finally, a 4D MRI scan is performed on the target object based on the target scan duration to obtain a target MRI image corresponding to the target scan duration, and internal target region delineation is performed based on the target MRI image. It can determine the appropriate target scanning time, shorten the 4D magnetic resonance scanning time of the target object, and improve the accuracy of internal target area delineation.

[0137] It should be noted that the above functions or steps that can be implemented by the computer-readable storage medium or computer device can be found in the relevant descriptions of the server side and the client side in the aforementioned method embodiment. To avoid repetition, they will not be described one by one here.

[0138] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0139] Those skilled in the art will clearly understand that for the sake of convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0140] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A method for delineating an internal target area based on 4D magnetic resonance imaging, characterized in that: The internal target area delineation method based on 4D magnetic resonance imaging includes: Acquiring a first abdominal 4D magnetic resonance image and each second abdominal 4D magnetic resonance image, wherein the first abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a first scan duration, and the second abdominal 4D magnetic resonance image is obtained by performing a 4D magnetic resonance scan according to a second scan duration, the first scan duration is greater than the second scan duration, and the first scan duration is greater than or equal to an actual abdominal radiotherapy duration; Determining a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image; determining a target scan duration according to the first probability distribution and each of the second probability distributions, wherein the target scan duration is less than the actual abdominal radiotherapy duration; According to the target scanning time, a 4D magnetic resonance scan is performed on the target object to obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and an internal target area is delineated based on the target nuclear magnetic resonance image.

2. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 1, characterized in that: The step of determining the first probability distribution based on the preset organ reference position and the first abdominal 4D magnetic resonance image, and determining each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image, includes: constructing a first organ respiratory displacement histogram based on a preset organ reference position and the first abdominal 4D magnetic resonance imaging; Performing fitting based on the respiratory displacement histogram of the first organ to obtain a first probability distribution; constructing a second organ respiratory displacement histogram according to the preset organ reference position and the second abdominal 4D magnetic resonance imaging; Fitting is performed according to the second organ respiratory displacement histogram to obtain a second probability distribution.

3. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 1, characterized in that: The step of determining the target scanning duration according to the first probability distribution and each of the second probability distributions includes: Determining a first PDF repeatability coefficient according to the first probability distribution and a preset PDF repeatability coefficient formula; Determining a second PDF repeatability coefficient according to each of the second probability distributions and a preset PDF repeatability coefficient formula; A target scanning time is determined according to the first PDF repeatability coefficient and the second PDF repeatability coefficient.

4. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 3, characterized in that: The step of determining a first PDF repeatability coefficient according to the first probability distribution and a preset PDF repeatability coefficient formula includes: Extracting a probability distribution corresponding to a preset third scanning duration from the first probability distribution as a third probability distribution; Extracting respective probability distributions corresponding to a preset scan duration set from the first probability distribution as respective fourth probability distributions, wherein the scan duration set includes a plurality of different scan durations, and the third scan duration is greater than or equal to the longest scan duration in the scan duration set; According to a preset PDF repeatability coefficient formula, the PDF repeatability coefficients of the third probability distribution and each of the fourth probability distributions are calculated respectively to obtain each first PDF repeatability coefficient.

5. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 3, characterized in that: The step of determining the second PDF repeatability coefficient according to each of the second probability distributions and a preset PDF repeatability coefficient formula includes: Selecting one second probability distribution from each second probability distribution as the fifth probability distribution, and selecting the second probability distributions other than the fifth probability distribution from each second probability distribution as the sixth probability distribution; For each sixth probability distribution, extracting probability distributions corresponding to a preset scanning duration set from the sixth probability distribution as seventh probability distributions; According to a preset PDF repeatability coefficient formula, the PDF repeatability coefficients of the fifth probability distribution and each of the seventh probability distributions are calculated respectively to obtain each second PDF repeatability coefficient.

6. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 3, characterized in that: The step of determining a target scanning time according to the first PDF repeatability coefficient and the second PDF repeatability coefficient includes: Perform fitting according to the first PDF repeatability coefficient, the first scanning time, and a preset fitting function to obtain a first fitting formula; Perform fitting according to the second PDF repeatability coefficient, the second scanning time, and a preset fitting function to obtain a second fitting formula; A target scanning duration is determined according to the first fitting formula and the second fitting formula.

7. The internal target area delineation method based on 4D magnetic resonance imaging according to claim 6, characterized in that: The step of determining the target scanning duration according to the first fitting formula and the second fitting formula includes: Calculating according to the first fitting formula and the preset first PDF reproducibility curve value to obtain a fourth scanning time length; Calculating according to the second fitting formula and the preset second PDF reproducibility curve value to obtain a fifth scanning time; The target scanning duration is determined according to the fourth scanning duration and the fifth scanning duration.

8. A device for delineating an internal target area based on 4D magnetic resonance imaging, characterized in that: The internal target area delineation device based on 4D magnetic resonance imaging comprises: an acquisition module, configured to acquire a first 4D abdominal MRI image and each second 4D abdominal MRI image, wherein the first 4D abdominal MRI image is obtained by performing a 4D MRI scan according to a first scan duration, and the second 4D abdominal MRI image is obtained by performing a 4D MRI scan according to a second scan duration, and the first scan duration is greater than the second scan duration; a first determining module, configured to determine a first probability distribution based on a preset organ reference position and the first abdominal 4D magnetic resonance image, and to determine each second probability distribution based on the preset organ reference position and each second abdominal 4D magnetic resonance image; a second determining module, configured to determine a target scanning duration according to the first probability distribution and each of the second probability distributions; The delineation module is used to perform a 4D magnetic resonance scan on the target object according to the target scanning time, obtain a target nuclear magnetic resonance image corresponding to the target scanning time, and perform internal target area delineation based on the target nuclear magnetic resonance image.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the internal target area delineation method based on 4D magnetic resonance imaging according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the internal target area delineation method based on 4D magnetic resonance imaging according to any one of claims 1 to 7 are implemented.

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