Synchronous acquisition and playback method and system for nuclear magnetic resonance image

Abstract

The invention relates to the technical field of image processing, in particular to a synchronous acquisition and playback method and system for nuclear magnetic resonance images. The method comprises the steps that a high-resolution anatomical image is obtained, blood flow velocity information is coded for dynamic imaging, distortion data is corrected in real time, and analog signal data is output; the analog signal data are preprocessed, the preprocessed data are subjected to layered coding, a fixed-length abstract is generated, encryption processing is carried out, and encrypted data are output; decrypting the encrypted data, reconstructing a playback image sequence, and displaying the image sequence; the system comprises a data acquisition module, a fixed-length abstract generation module and a playback image sequence reconstruction module. By means of the mode, the change of blood flow along with time is dynamically displayed, and the assessment ability of lesion risks is improved.

Description

Technical Field

[0001] This invention relates to the field of image processing technology, and in particular to a method and system for synchronous acquisition and playback of nuclear magnetic resonance images. Background Technology

[0002] Magnetic resonance imaging (MRI), with its radiation-free operation, high soft tissue contrast, and multi-parameter imaging capabilities, has become the standard for diagnosing neurological, cardiovascular, and oncological diseases. However, traditional MRI techniques have significant limitations in dynamic blood flow imaging and real-time playback, making it difficult to meet the urgent clinical needs for hemodynamic assessment and intraoperative navigation.

[0003] Traditional MRI uses static image playback, which cannot dynamically show changes in blood flow over time (such as the blood flow pattern during the pulsation cycle of a cerebral aneurysm), thus limiting the ability to assess the risk of lesions. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for synchronous acquisition and playback of magnetic resonance images, aiming to solve the technical problem in the prior art that uses static image playback, which cannot dynamically display changes in blood flow over time, thus limiting the ability to assess the risk of lesions.

[0005] To achieve the above objectives, the present invention employs a method for synchronous acquisition and playback of nuclear magnetic resonance images, comprising the following steps: Acquire high-resolution anatomical images, encode blood flow velocity information for dynamic imaging, correct distortion data in real time, and output analog signal data; The analog signal data is preprocessed, the preprocessed data is hierarchically encoded, a fixed-length digest is generated, and then encrypted to output encrypted data. The encrypted data is decrypted, the image sequence is reconstructed and replayed, and the image sequence is displayed.

[0006] Among the steps are: acquiring high-resolution anatomical images, encoding blood flow velocity information for dynamic imaging, correcting distortion data in real time, and outputting analog signal data; Acquire high-resolution anatomical images, configure sequences, extract phase-contrast blood flow and remove background noise, and output imaging data; Gradient nonlinear correction is performed on the imaging data, motion artifacts are suppressed, and an analog signal is output.

[0007] After performing gradient nonlinear correction on the imaging data, suppressing motion artifacts, and outputting an analog signal: The analog signal is converted into a digital signal, the error is quantized, and the digital signal is standardized and packaged.

[0008] After the steps of converting analog signals to digital signals, quantizing errors, and standardizing and packaging the digital signals: Reconstruct the analog signal, restore the digital signal to an analog signal, and output it.

[0009] The steps include preprocessing analog signal data, performing hierarchical encoding on the preprocessed data, generating a fixed-length digest, encrypting the digest, and outputting encrypted data: The data was divided into layers of gray matter, white matter, cerebrospinal fluid, blood vessels, and background data. Layered compression encoding is performed on multiple data layers, and a fixed-length digest is generated; Session keys are generated for the multi-layer data layer, and the encoded data and fixed-length digests are encrypted separately.

[0010] Before the step of dividing the data into layers of gray matter, white matter, cerebrospinal fluid, blood vessels, and background data: The simulation data is sequentially subjected to noise filtering and signal normalization, and the preprocessed data is output.

[0011] The process includes generating session keys for multiple data layers and encrypting the encoded data and fixed-length digests respectively: The session key is encrypted and embedded in the ciphertext header, then the key is encapsulated, and the encrypted data is output.

[0012] In the steps of decrypting the encrypted data, reconstructing the playback image sequence, and displaying the image sequence: Decrypt the ciphertext header, obtain the session key, and restore the encoded data and fixed-length digest to verify the authentication label; The original layered data is restored, and the five layers of decoded data are superimposed according to transparency to synthesize a complete image. The image frames are arranged in time sequence for real-time playback. It provides simultaneous display of coronal, sagittal, and axial views.

[0013] The process includes the steps of decrypting the ciphertext header, obtaining the session key, restoring the encoded data and fixed-length digest, and verifying the authentication tag: Calculate a fixed-length digest of the decrypted data, compare it with the decrypted fixed-length digest, and output the comparison result.

[0014] This invention also provides a synchronous acquisition and playback system for nuclear magnetic resonance images, including a data acquisition module, a fixed-length summary generation module, and a playback image sequence reconstruction module; wherein: The data acquisition module is used to acquire high-resolution anatomical images, encode blood flow velocity information for dynamic imaging, correct distortion data in real time, and output analog signal data. The fixed-length digest generation module is used to preprocess analog signal data, perform hierarchical encoding on the preprocessed data, generate a fixed-length digest, perform encryption processing, and output encrypted data. The playback image sequence reconstruction module is used to decrypt encrypted data, reconstruct the playback image sequence, and display the image sequence.

[0015] The present invention discloses a method and system for synchronous acquisition and playback of MRI images, comprising a data acquisition module, a fixed-length summary generation module, and a playback image sequence reconstruction module, comprising the following steps: acquiring high-resolution anatomical images, encoding blood flow velocity information for dynamic imaging, correcting distortion data in real time, and outputting analog signal data; preprocessing the analog signal data, performing layered encoding on the preprocessed data, generating a fixed-length summary, encrypting it, and outputting encrypted data; decrypting the encrypted data, reconstructing the playback image sequence, and displaying the image sequence; through the above method, the dynamic display of blood flow changes over time is achieved, improving the ability to assess the risk of lesions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart of the steps of the synchronous acquisition and playback method of nuclear magnetic resonance images of the present invention.

[0018] Figure 2 This is a flowchart of steps S100 of the present invention.

[0019] Figure 3 This is a flowchart of steps S200 of the present invention.

[0020] Figure 4 This is a flowchart of steps S300 of the present invention.

[0021] Figure 5 This is a schematic diagram of the synchronous acquisition and playback system for nuclear magnetic resonance images of the present invention.

[0022] Figure 6 This is a schematic diagram of the electronic device of the present invention.

[0023] 401 - Data acquisition module, 402 - Fixed-length summary generation module, 403 - Playback image sequence reconstruction module. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0025] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0026] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0027] Please see Figures 1-4 This invention provides a method for synchronous acquisition and playback of nuclear magnetic resonance images, comprising the following steps: S100: Acquires high-resolution anatomical images, encodes blood flow velocity information for dynamic imaging, corrects distortion data in real time, and outputs analog signal data.

[0028] In this embodiment, high-resolution anatomical images are acquired, and blood flow velocity information is encoded for dynamic imaging. Distortion data is corrected in real time, and analog signal data is output. The specific process is as follows: S101: Acquire high-resolution anatomical images, configure sequences, extract phase-contrast blood flow and remove background noise, and output imaging data; S102: Performs gradient nonlinear correction on the imaging data, suppresses motion artifacts, and outputs an analog signal; S103: Converts analog signals into digital signals, quantizes errors, and standardizes and encapsulates digital signals; S104: Reconstruct analog signal, restore digital signal to analog signal, and output.

[0029] In the above process, anatomical structures and three-dimensional blood flow velocity fields are acquired simultaneously by combining T1 / T2 weighted sequences of MRI with 4D Flow MRI technology.

[0030] Parallel imaging is used to accelerate data acquisition, reducing scanning time by 40% to 60%.

[0031] Blood flow information is extracted, and blood flow velocity is calculated using the phase comparison method to generate a time-resolved vector diagram. Background field suppression algorithms (such as PEAK-GRAPPA) are applied to eliminate phase errors caused by eddies.

[0032] Noise suppression is achieved by using nonlocal mean filtering to remove random noise while preserving details of the vessel edges.

[0033] Dynamic threshold segmentation automatically adjusts the segmentation threshold based on blood flow velocity distribution to distinguish between arteries, veins, and microcirculation.

[0034] Gradient nonlinear correction: A pre-stored magnetic field gradient mapping table is used to perform inverse transformation compensation on the image spatial coordinates; B0 field diagram correction is used to eliminate geometric distortion caused by the inhomogeneity of the main magnetic field.

[0035] Motion artifact suppression involves real-time tracking of head motion (e.g., optical tracking systems) and image correction via inverse registration.

[0036] For cerebrospinal fluid fluctuations caused by heartbeats, ECG-gating was used to collect data synchronously.

[0037] Signal digitization: 16-bit ADC quantization sampling, with a dynamic range covering signal strength from -10dB to +30dB.

[0038] Standardized encapsulation: Add DICOM tags (such as PatientID, StudyDate) and private tags to store blood flow parameters.

[0039] Analog signal reconstruction: The signal is reconstructed using a digital-to-analog converter at a sampling rate of 10MHz, with bandwidth matching the original analog equipment (such as an ultrasound probe). Jitter noise is added to improve the quantization signal-to-noise ratio of low-resolution signals.

[0040] Real-time monitoring: An oscilloscope module is embedded at the signal output end to display the waveform spectrum in real time and trigger an alarm when there is an anomaly (such as a sudden drop of 30% in signal amplitude).

[0041] S200: Preprocesses analog signal data, performs hierarchical encoding on the preprocessed data, generates a fixed-length digest, encrypts it, and outputs encrypted data.

[0042] In this embodiment, the analog signal data is preprocessed, the preprocessed data is hierarchically encoded to generate a fixed-length digest, and then encrypted to output encrypted data. The specific process is as follows: S201: Perform noise filtering and signal normalization on the analog data in sequence, and output the preprocessed data; S202: Divide the data into layers of gray matter, white matter, cerebrospinal fluid, blood vessels, and background data; S203: Perform layered compression encoding on multi-layered data and generate a fixed-length digest; S204: Generate session keys for multiple data layers and encrypt the encoded data and fixed-length digests respectively; S205: Encrypt the session key and embed it into the ciphertext header, encapsulate the key, and output the encrypted data.

[0043] In the above process, wavelet thresholding (Daubechies4 wavelet basis) is used for high-frequency noise to preserve the transient characteristics of blood flow signals. Polynomial fitting (3rd order polynomial) is used to remove baseline shift for low-frequency drift.

[0044] Signal normalization: Dynamic range compression: Maps the signal to the [μ-3σ, μ+3σ] interval (where μ is the mean and σ is the standard deviation) to avoid the influence of extreme values. Normalized to 8-bit grayscale (0-255), compatible with older display devices.

[0045] Layering by anatomical structure: Image data is divided into five layers—gray matter, white matter, cerebrospinal fluid, blood vessels, and background—using k-means clustering (k=5) to facilitate subsequent coding optimization.

[0046] Layered compression coding is used, with H.265 / HEVC intra-frame coding (compression ratio = 10:1) applied to the vascular layer and JPEG-LS lossless coding (compression ratio = 2:1) applied to the background layer, balancing compression efficiency and data fidelity.

[0047] The SHA-3 (512-bit) algorithm is used to generate a hash digest for each layer of data to ensure data integrity (collision probability < 10). -18 ).

[0048] The five-level digests are combined into a single 512-bit digest using an XOR operation, reducing storage overhead.

[0049] Hybrid encryption scheme: Session key: Each layer generates an AES-256 key independently, which is then embedded in the ciphertext after being encrypted using RSA-3072.

[0050] Data encryption: GCM mode (Galois / CounterMode) is used to provide both confidentiality and integrity protection.

[0051] The master key is stored using a hardware security module (HSM) to prevent software-level attacks.

[0052] Key rotation: The session key is automatically changed every 24 hours, and the old key is encrypted and archived.

[0053] S300: Decrypts the encrypted data, reconstructs and replays the image sequence, and displays the image sequence.

[0054] In this embodiment, the encrypted data is decrypted, the reconstructed image sequence is replayed, and the image sequence is displayed. The specific process is as follows: S301: Decrypt the ciphertext header, obtain the session key, and restore the encoded data and fixed-length digest to verify the authentication tag; S302: Calculate the fixed-length digest of the decrypted data, compare it with the decrypted fixed-length digest, and output the comparison result; S303: Restore the original layered data, combine the five layers of decoded data according to transparency to synthesize a complete image, arrange the image frames according to time sequence, and perform real-time playback; S304: Provides simultaneous display of coronal, sagittal, and axial views.

[0055] In the above process, the RSA encrypted session key in the ciphertext header is decrypted using the master key in the HSM.

[0056] Verify the key's validity period (e.g., expiration timestamp) and reject expired keys.

[0057] Integrity verification involves calculating the SHA-3 digest of the decrypted data and comparing it with the digest in the ciphertext; the bit error rate (BER) must be greater than 10. -9 Retransmission is triggered at that time.

[0058] H.265 decoding is performed on the vascular layer, and JPEG-LS decoding is performed on the background layer to restore the original layered data (peak signal-to-noise ratio PSNR > 45dB).

[0059] The five layers of decoded data are superimposed according to transparency (vascular layer transparency = 0.8, other layers = 1.0) to synthesize a complete image, preserving anatomical and blood flow information.

[0060] Image frames are arranged in a time sequence, and real-time playback at 30 frames per second (latency <33ms) is achieved through OpenGL hardware acceleration.

[0061] Image display and interaction: Provides simultaneous display of coronal, sagittal and axial three views, and supports reconstruction of oblique planes at any angle (reconstruction time < 500ms).

[0062] Quantitative blood flow analysis, integrated with the QFlow software module, automatically calculates the flow velocity and flow rate of blood vessel cross sections (error <5%), and generates color-coded blood flow maps (velocity range = 0~150cm / s). Corresponding to the aforementioned embodiments of the synchronous acquisition and playback method for nuclear magnetic resonance images, this application also provides embodiments of a synchronous acquisition and playback system for nuclear magnetic resonance images.

[0063] Figure 5 This is a block diagram illustrating a synchronous acquisition and playback system for nuclear magnetic resonance images according to an exemplary embodiment. (Refer to...) Figure 5 The system may include: a data acquisition module 401, a fixed-length summary generation module 402, and a playback image sequence reconstruction module 403; wherein: The data acquisition module 401 is used to acquire high-resolution anatomical images, encode blood flow velocity information for dynamic imaging, correct distortion data in real time, and output analog signal data. The fixed-length digest generation module 402 is used to preprocess analog signal data, perform layered encoding on the preprocessed data, generate a fixed-length digest, perform encryption processing, and output encrypted data. The playback image sequence reconstruction module 403 is used to decrypt encrypted data, reconstruct the playback image sequence, and display the image sequence.

[0064] In this embodiment, the data acquisition module 401 acquires high-resolution anatomical images, encodes blood flow velocity information for dynamic imaging, corrects distortion data in real time, and outputs analog signal data; the fixed-length summary generation module 402 preprocesses the analog signal data, performs layered encoding on the preprocessed data, generates a fixed-length summary, encrypts it, and outputs encrypted data; the playback image sequence reconstruction module 403 decrypts the encrypted data, reconstructs the playback image sequence, and displays the image sequence; through the above methods, the dynamic display of blood flow changes over time is achieved, improving the ability to assess the risk of lesions.

[0065] Regarding the system in the above embodiments, the specific ways in which each module performs operations have been described in detail in the embodiments related to the method, and will not be elaborated here.

[0066] For the system embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0067] Accordingly, this application also provides an electronic device, comprising: one or more processors; a memory for storing one or more programs; and, when the one or more programs are executed by the one or more processors, causing the one or more processors to implement the synchronous acquisition and playback method of nuclear magnetic resonance images as described above. Figure 6 The diagram shown is a hardware structure diagram of any device with data processing capabilities within a synchronous acquisition and playback system for nuclear magnetic resonance images provided in an embodiment of the present invention, except... Figure 6 In addition to the processor, memory, and network interface shown, any data processing device in the embodiment may also include other hardware depending on the actual function of the data processing device, which will not be described in detail here.

[0068] Accordingly, this application also provides a computer-readable storage medium storing computer instructions, which, when executed by a processor, implement the synchronous acquisition and playback method of MRI images as described above. The computer-readable storage medium can be an internal storage unit of any data-processing device as described in any of the foregoing embodiments, such as a hard disk or memory. The computer-readable storage medium can also be an external storage device, such as a plug-in hard disk, smart media card (SMC), SD card, flash card, etc., equipped on the device. Furthermore, the computer-readable storage medium can include both internal storage units of any data-processing device and external storage devices. The computer-readable storage medium is used to store the computer program and other programs and data required by the data-processing device, and can also be used to temporarily store data that has been output or will be output.

[0069] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0070] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A method of synchronized acquisition playback of nuclear magnetic resonance images, characterized by, It comprises the following steps: Obtain high-resolution anatomical images and encode blood flow velocity information for dynamic imaging, real-time distortion correction data, output analog signal data; Preprocess the analog signal data, layer-encode the preprocessed data, generate a fixed-length digest, and encrypt the data, output encrypted data; Decrypt the encrypted data, reconstruct the playback image sequence, and display the image sequence.

2. The method for synchronized acquisition playback of MR images of claim 1, wherein, In the step of obtaining high-resolution anatomical images and encoding blood flow velocity information for dynamic imaging, real-time distortion correction data, output analog signal data: Obtain high-resolution anatomical images, configure sequences, extract phase-contrast blood flow and remove background noise, and output imaging data; Gradient non-linear correction is performed on the imaging data, and motion artifacts are suppressed, and analog signals are output.

3. The method for synchronized acquisition playback of MR images of claim 2, wherein, After the step of gradient non-linear correction on the imaging data and suppression of motion artifacts, output analog signal: Convert the analog signal to a digital signal, quantify the error, and standardize and package the digital signal.

4. The method for synchronized acquisition and playback of MR images of claim 3, wherein, After the step of converting the analog signal to a digital signal, quantifying the error, and standardizing and packaging the digital signal: Reconstruct the analog signal, restore the digital signal to the analog signal, and output.

5. The method for synchronized acquisition and playback of MR images of claim 1, wherein, In the step of preprocessing analog signal data, layer-encoding preprocessed data, generating a fixed-length digest, and encrypting data, output encrypted data: Divide the data into brain gray matter, white matter, cerebrospinal fluid, blood vessels and background data layers; Layered compression encoding is performed on the multi-layer data layer, and a fixed-length digest is generated; Generate a session key for the multi-layer data layer, and encrypt the encoded data and fixed-length digest separately.

6. The method for synchronized acquisition and playback of MR images of claim 5, wherein, Before the step of dividing the data into brain gray matter, white matter, cerebrospinal fluid, blood vessels and background data layers: Noise filtering and signal normalization are performed on the analog data in sequence, and the preprocessed data is output.

7. The method for synchronized acquisition and playback of MR images of claim 5, wherein, After the step of generating a session key for the multi-layer data layer and encrypting the encoded data and fixed-length digest separately: Embed the encrypted session key in the ciphertext header, perform key packaging, and output encrypted data.

8. The method for synchronized acquisition and playback of MR images of claim 5, wherein, In the step of decrypting the encrypted data, reconstructing the playback image sequence, and displaying the image sequence: Decrypt the ciphertext header, obtain the session key, restore the encoded data and fixed-length digest, and verify the authentication tag; Restore the original layered data, superimpose the five layers of decoded data to form a complete image according to transparency, arrange the image frames in time sequence, and perform real-time playback; Provide simultaneous display of coronal, sagittal and axial views.

9. The method for synchronized acquisition and playback of MR images of claim 8, wherein, After the step of decrypting the ciphertext header, obtaining the session key, restoring the encoded data and fixed-length digest, and verifying the authentication tag: Calculate the fixed-length digest of the decrypted data and compare it with the decrypted fixed-length digest, and output the comparison result.

10. A synchronized acquisition playback system of nuclear magnetic resonance images, applied to the synchronized acquisition playback method of nuclear magnetic resonance images according to claim 1, characterized in that, It comprises a data acquisition module, a fixed-length digest generation module, and a playback image sequence reconstruction module; wherein: The data acquisition module is used to obtain high-resolution anatomical images and encode blood flow velocity information for dynamic imaging, real-time distortion correction data, and output analog signal data; The fixed-length abstract generation module is used for pre-processing analog signal data, layer coding the pre-processed data, generating a fixed-length abstract, and performing encryption processing to output encrypted data. The playback image sequence reconstruction module is used for decrypting the encrypted data, reconstructing a playback image sequence, and displaying the image sequence.

Images