Magnetic Resonance Spectroscopy Fitting Method, System and Terminal

Abstract

The magnetic resonance spectroscopy fitting method, system and terminal of the present invention obtain the real part data of the frequency-domain spectrum by performing Fourier transform on the collected spectrum data, select a limited frequency range of the spectrum of interest, then determine the frequency coordinate index data relative to the entire spectrum, and further generate a corresponding limited spectrum from the real part data; based on the set spectrum baseline extension value and the frequency coordinate index data, perform frequency extension on the limited spectrum, and set the sampling interval time and the number of acquisition points of the time-domain and frequency-domain spectrum fitting function, and finally fit the extended spectrum. The present invention uses the same sampling interval time as the collected data to construct the time-domain and frequency-domain spectrum fitting function, ensuring the minimization of the baseline; before fitting, perform artificial spectrum frequency extension and spectrum baseline extension so that the extended spectrum range is equal to the entire spectrum range; reduce the baseline influence by setting the spectrum baseline extension value; fit the extended spectrum after extension, thereby improving the accuracy of the spectrum fitting parameters.

Description

Technical Field

[0001] The present invention relates to the field of magnetic resonance, and particularly to a magnetic resonance spectroscopy fitting method, system and terminal. Background Art

[0002] Magnetic resonance spectroscopy (MRS) is currently the only technique that can non-invasively observe the metabolism and biochemical changes of living tissues. Since the degree of magnetic shielding experienced by atomic nuclei in different compounds is different, the atomic nuclei will have different resonance frequencies, namely the so-called chemical shift, which is expressed in the unit "parts per million" (ppm) in practical applications. Since the gyromagnetic ratio of hydrogen protons (1H) is the largest (42.58 MHz / T) and the natural abundance in the human body is also the largest, the MRS signal generated is the strongest, so it is the most widely used in clinical applications. The manifestation form of MRS is to transform the function distributed in the time domain into a spectrum distributed in the frequency domain (chemical shift).

[0003] Magnetic resonance spectroscopy fitting is of great significance for the quantification of spectra. It can remove the noise in the spectra, estimate the quantitative parameters of metabolites, and thus obtain the relative concentration or absolute concentration of metabolites. Currently, the fitting methods of spectra are divided into two categories. One is to quantify the original data or preprocessed data in the time domain, and the other is to quantify the Fourier transform spectral signal after processing in the frequency domain. A time-domain frequency-domain fitting (TDFD fitting) developed later combines the advantages of the above two methods. It uses a time-domain model to fit the frequency-domain spectral data. This method not only has the advantage of being easy to process truncated data in the time-domain method but also has the simplicity of frequency selection fitting in the frequency-domain method.

[0004] The time-domain frequency-domain fitting method first establishes a time-domain fitting model. Commonly used fitting models include Gaussian line shape, Lorentz line shape, Voigt line shape, etc. Then, the time-domain fitting model is Fourier-transformed, and a cost equation is established in the frequency domain using the spectral data within a limited range and the model results. Next, the cost equation is solved by the nonlinear least squares method to estimate the fitting parameters. Finally, the estimated fitting parameters are input into the time-domain fitting model, and after Fourier transformation, the fitting curve over the entire spectral range is obtained.

[0005] In the TDFD fitting method, fitting is required for a limited spectral peak range. Usually, a varying sampling interval time (dwelltime) is used in the fitting model to fit spectral peaks in different ranges of interest. For single-peak fitting, in order to correspond to a limited frequency range, it is necessary to artificially increase the sampling interval time (dwelltime), narrow the corresponding spectral width of the wave spectrum, and make the frequency range of the model correspond to the limited spectral range of interest. Through experimental simulation, it can be observed that an increased dwelltime will raise the corresponding baseline, and the multiple difference in the number of acquired points is the multiple difference in the baseline amplitude. The dwelltime1 of the reference data is 0.0005 s, generating the reference baseline amplitude; when dwelltime2 = 0.0005 * 10 s, the baseline amplitude differs from the reference baseline by approximately 10 times; when dwelltime2 = 0.0005 * 20 s, the baseline amplitude differs from the reference baseline by approximately 20 times; when dwelltime3 = 0.0005 * 30 s, the baseline amplitude differs from the reference baseline by approximately 30 times.

[0006] Since the TDFD fitting method uses an increased sampling interval time and a reduced number of sampling points, it causes the model baseline to rise; at the same time, for small peaks, it is difficult to select a limited range, and overfitting and an increase in the full width at half maximum of the spectral line are likely to occur, resulting in inaccurate parameter estimation, and there are deviations in the spectral peak width and the chemical shift position of the spectral peak obtained by fitting; compared with the data to be fitted, the systematic error generated by the obtained fitting curve is relatively large. Summary of the Invention

[0007] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a magnetic resonance spectroscopy fitting method, system, and terminal to solve the above prior art problems.

[0008] To achieve the above and other related objectives, the present invention provides a method for magnetic resonance spectroscopy fitting. The method includes: performing Fourier transform on the collected spectral data and obtaining the real part data of the corrected frequency-domain spectrum; selecting a finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest; determining the frequency coordinate index data of the finite spectrum relative to the entire spectrum based on the finite frequency range of the spectrum of interest; wherein the frequency coordinate index data includes: the frequency coordinate indices of the left and right endpoints of the finite spectrum corresponding to the entire spectrum respectively; generating a corresponding finite spectrum from the real part data based on the frequency coordinate index data; performing frequency expansion on the finite spectrum according to the spectral range corresponding to the collected spectral data based on the set spectral baseline expansion value and the frequency coordinate index data to obtain a corresponding expanded spectrum; setting the sampling interval time and the number of sampling points corresponding to the collected spectral data for the time-domain and frequency-domain spectral fitting function; performing parameter fitting and solution based on the expanded spectrum according to the time-domain and frequency-domain spectral fitting function to obtain fitting parameters and a fitting curve.

[0009] In an embodiment of the present invention, the sampling interval time is calculated based on the acquisition bandwidth of the collected spectral data; the number of sampling points is obtained based on the number of points of the collected spectral data.

[0010] In an embodiment of the present invention, the selecting a finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest includes: selecting a left-right symmetric finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest and the selected frequency range.

[0011] In an embodiment of the present invention, the spectral baseline expansion value is set to zero.

[0012] In an embodiment of the present invention, the performing frequency expansion on the finite spectrum according to the spectral range corresponding to the collected spectral data based on the set spectral baseline expansion value and the frequency coordinate index data to obtain a corresponding expanded spectrum includes: performing frequency expansion on the finite spectrum based on the set spectral baseline expansion value and the spectral range of the collected spectral data to generate a preliminary expanded spectrum with the abscissa value of the entire spectral range and the baseline being the spectral baseline expansion value; filling the finite range spectral data into the corresponding range of the preliminary expanded spectrum based on the frequency coordinate index data to obtain a corresponding expanded spectrum.

[0013] In an embodiment of the present invention, the performing Fourier transform on the collected spectral data and obtaining the real part data of the corrected frequency-domain spectrum includes: performing Fourier transform on the collected spectral data to obtain the preliminary real part data of the frequency-domain spectrum; performing phase correction and chemical shift correction on the preliminary real part data of the frequency-domain spectrum to obtain the real part data of the frequency-domain spectrum.

[0014] To achieve the above and other related objectives, the present invention provides a magnetic resonance spectroscopy fitting system, which includes: a Fourier transform module for performing Fourier transform on the collected spectroscopy data and obtaining the real part data of the corrected frequency-domain spectroscopy; a finite frequency range selection module connected to the Fourier transform module for selecting a finite frequency range of the spectroscopy of interest based on the theoretical chemical shift position of the spectral peak of interest; a frequency index determination module connected to the finite frequency range selection module for determining the frequency coordinate index data of the finite spectroscopy relative to the entire frequency spectrum based on the finite frequency range of the spectroscopy of interest; wherein the frequency coordinate index data includes: the frequency coordinate indices corresponding to the left and right endpoints of the finite spectroscopy in the entire frequency spectrum respectively; a finite spectroscopy generation module connected to the frequency index determination module for generating the corresponding finite spectroscopy from the real part data based on the frequency coordinate index data; a frequency expansion module connected to the finite spectroscopy generation module for expanding the frequency of the finite spectroscopy according to the spectral range corresponding to the collected spectroscopy data based on the set spectroscopy baseline expansion value and the frequency coordinate index data to obtain the corresponding expanded spectroscopy; a function setting module connected to the frequency expansion module for setting the sampling interval time and the number of sampling points corresponding to the collected spectroscopy data of the time-domain and frequency-domain spectroscopy fitting function; a spectroscopy fitting module connected to the function setting module for performing parameter fitting and solution based on the time-domain and frequency-domain spectroscopy fitting function according to the expanded spectroscopy to obtain the fitting parameters and the fitting curve.

[0015] In an embodiment of the present invention, the sampling interval time is calculated based on the acquisition bandwidth of the collected spectroscopy data; the number of sampling points is obtained based on the number of points of the collected spectroscopy data.

[0016] In an embodiment of the present invention, the spectroscopy baseline expansion value is set to zero.

[0017] To achieve the above and other related objectives, the present invention provides a magnetic resonance spectroscopy fitting terminal, including: one or more memories and one or more processors; the one or more memories for storing computer programs; the one or more processors connected to the memories for running the computer programs to execute the magnetic resonance spectroscopy fitting method.

[0018] As described above, the present invention is a magnetic resonance spectroscopy fitting method, system and terminal, which has the following beneficial effects: The present invention obtains the real part data of the frequency-domain spectrum by performing Fourier transform on the collected spectrum data, selects a limited frequency range of the spectrum of interest, then determines the frequency coordinate index data relative to the entire spectrum, and further generates a corresponding limited spectrum from the real part data; Based on the set spectrum baseline extension value and the frequency coordinate index data, the limited spectrum is frequency-expanded, and the sampling interval time and the number of acquisition points of the time-domain frequency-domain spectrum fitting function are set, and finally the expanded spectrum is fitted. The present invention uses the same sampling interval time (dwelltime) as the collected data to construct the time-domain frequency-domain spectrum fitting function, ensuring the minimization of the baseline; Before fitting, artificial spectrum frequency expansion and spectrum baseline expansion are performed so that the expanded spectrum range is equal to the entire spectrum range; By setting the spectrum baseline extension value, the influence of the baseline is reduced; The expanded spectrum after expansion is fitted, thereby improving the accuracy of the spectrum fitting parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It shows a schematic flow chart of the magnetic resonance spectroscopy fitting method in an embodiment of the present invention.

[0020] Figure 2 It shows a schematic flow chart of the magnetic resonance spectroscopy fitting method in an embodiment of the present invention.

[0021] Figure 3 a shows a schematic diagram of the TDFD fitting result using this solution.

[0022] Figure 3 b shows a schematic diagram of the fitting result using the original TDFD fitting.

[0023] Figure 4 It shows a schematic structural diagram of the magnetic resonance spectroscopy fitting system in an embodiment of the present invention.

[0024] Figure 5 It shows a schematic structural diagram of the magnetic resonance spectroscopy fitting terminal in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following specifically illustrates the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0026] It should be noted that in the following description, with reference to the accompanying drawings, several embodiments of the present invention are described. It should be understood that other embodiments may also be used, and mechanical composition, structure, electrical, and operational changes may be made without departing from the spirit and scope of the present invention. The following detailed description should not be considered restrictive, and the scope of the embodiments of the present invention is only defined by the claims of the published patent. The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. Spatially related terms, such as "upper", "lower", "left", "right", "below", "beneath", "lower part", "above", "upper part", etc., may be used in the text to facilitate the description of the relationship between one element or feature shown in the drawings and another element or feature.

[0027] Throughout the specification, when it is said that a part is "connected" to another part, this includes not only the case of "direct connection", but also the case of "indirect connection" with other elements placed therebetween. In addition, when it is said that a certain part "includes" a certain constituent element, unless there is a particularly contrary record, it does not exclude other constituent elements, but means that other constituent elements may also be included.

[0028] The first, second, and third, etc. terms mentioned therein are used to illustrate various parts, components, regions, layers, and / or segments, but are not limited thereto. These terms are only used to distinguish a part, component, region, layer, or segment from other parts, components, regions, layers, or segments. Therefore, the first part, component, region, layer, or segment described below may refer to the second part, component, region, layer, or segment within the scope not exceeding the present invention.

[0029] Furthermore, as used herein, the singular forms "a", "an", and "the" are also intended to include the plural forms unless the context indicates otherwise. It should be further understood that the terms "comprise" and "include" indicate the presence of the described features, operations, elements, components, items, types, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, operations, elements, components, items, types, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or meaning any one or any combination. Therefore, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C". An exception to this definition only occurs when the combination of elements, functions, or operations is inherently mutually exclusive in some way.

[0030] A magnetic resonance spectroscopy fitting method of the present invention obtains the real part data of the corrected frequency-domain spectrum by performing Fourier transform on the collected spectrum data, selects a limited frequency range of the spectrum of interest, then determines the frequency coordinate index data of the limited spectrum relative to the entire spectrum, and generates the corresponding limited spectrum from the real part data; then, based on the set spectrum baseline extension value and the frequency coordinate index data, frequency extension is performed on the limited spectrum according to the spectrum range corresponding to the collected spectrum data, and the sampling interval time and the number of sampling points corresponding to the collected spectrum data of the time-domain and frequency-domain spectrum fitting function are set, and finally the extended spectrum is fitted. The present invention uses the same sampling interval time (dwell time) as the collected data to construct the time-domain and frequency-domain spectrum fitting function, ensuring the minimization of the baseline; before fitting, artificial spectrum frequency extension and spectrum baseline extension are performed so that the extended spectrum range is equal to the entire spectrum range; the influence of the baseline is reduced by setting the spectrum baseline extension value; the extended spectrum after extension is fitted, thereby improving the accuracy of the spectrum fitting parameters.

[0031] The following takes the attached drawings as a reference and details the embodiments of the present invention so that those skilled in the technical field of the present invention can easily implement it. The present invention can be embodied in many different forms and is not limited to the embodiments described herein.

[0032] As Figure 1 Fig. shows a schematic flowchart of a magnetic resonance spectroscopy fitting method in an embodiment of the present invention.

[0033] The method includes:

[0034] Step S11: Perform Fourier transform on the collected spectrum data and obtain the real part data of the corrected frequency-domain spectrum.

[0035] In one embodiment, step S11 includes:

[0036] Perform Fourier transform on the collected spectrum data to obtain the preliminary real part data of the frequency-domain spectrum;

[0037] Perform phase correction and chemical shift correction on the preliminary real part data of the frequency-domain spectrum to obtain the real part data of the frequency-domain spectrum.

[0038] It should be noted that Gaussian filtering is performed on the collected spectrum data before performing Fourier transform.

[0039] Step S12: Select a limited frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest.

[0040] In one embodiment, the selection of the finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectrum peak of interest includes: selecting a finite frequency range of the spectrum of interest that is symmetric about the left and right based on the theoretical chemical shift position of the spectrum peak of interest and the selected frequency range. Specifically, according to the theoretical chemical shift position of the spectrum peak of interest, a smaller frequency range is selected to generate a finite spectrum. The selection principle is to be symmetric about the theoretical position of the spectrum peak and basically located at the baseline position of the spectrum peak of interest; for example, the theoretical chemical shift position of the Cr2 spectrum peak is 3.193 ppm. Assuming that the bottom width of the Cr2 spectrum peak is 0.2 ppm, that is, a 0.2 ppm frequency range is selected to generate a finite spectrum. The selection principle is to be symmetric about the theoretical position of 3.193 ppm of the spectrum peak. The selection range of the Cr2 finite spectrum is (3.193 + 0.1, 3.193 - 0.1) ppm.

[0041] Step S13: Based on the finite frequency range of the spectrum of interest, determine the frequency coordinate index data of the finite spectrum relative to the entire spectrum.

[0042] Specifically, the frequency coordinate index data includes: the frequency coordinate indices (Xleft and Xright) corresponding to the left and right endpoints of the finite spectrum relative to the entire spectrum, which are used to determine the left and right positions of the spectrum baseline extension; that is, it is determined that the number of points corresponding to the endpoints of 3.193 + 0.1 and 3.193 - 0.1 is Xleft = 997 and Xright = 1050.

[0043] Step S14: Based on the frequency coordinate index data, generate the corresponding finite spectrum from the real part data.

[0044] Step S15: Based on the set spectrum baseline extension value and the frequency coordinate index data, perform frequency extension on the finite spectrum according to the spectrum range corresponding to the collected spectrum data to obtain the corresponding extended spectrum.

[0045] In one embodiment, a zero value (0.0) is set as the spectrum baseline extension value; in the spectrum post-processing, it is assumed that the spectrum has completed post-processing steps such as phase correction and baseline correction, and the spectrum presents an absorption line shape, that is, the spectrum peak is completely symmetric. At this time, the spectrum baseline is relatively flat, so the spectrum baseline extension value is set to 0.0.

[0046] In one embodiment, the performing frequency extension on the finite spectrum according to the spectrum range corresponding to the collected spectrum data based on the set spectrum baseline extension value and the frequency coordinate index data to obtain the corresponding extended spectrum includes:

[0047] Frequency-expand the finite spectrum based on the set spectral baseline extension value and the spectral range of the acquired spectral data to generate a preliminary extended spectrum with the abscissa values of the entire spectral range and the baseline being the spectral baseline extension value. Specifically, according to the spectral range of the acquired spectrum, perform frequency extension to generate the abscissa of the entire spectral peak range, and at the same time generate a preliminary extended spectrum with a baseline of zero value.

[0048] Based on the frequency coordinate index data, fill the finite-range spectral data into the corresponding range of the preliminary extended spectrum to obtain the corresponding extended spectrum. Specifically, according to the obtained frequency coordinate index, fill the finite-range spectral data into the corresponding range (Xleft~Xright) of the extended spectrum to complete the spectrum extension.

[0049] Among them, the finite-range spectral data is the corresponding data of the number of points calculated from the frequency coordinate index. For example, the calculated frequency coordinate index (Xleft = 997 and Xright = 1050), and the finite-range spectral data (Xright - Xleft = 1050 – 997 = 53 point data) is filled into the extended spectrum.

[0050] Step S16: Set the sampling interval time and the number of acquisition points corresponding to the acquired spectral data for the time-domain and frequency-domain spectral fitting function.

[0051] In an embodiment, the sampling interval time is calculated based on the acquisition bandwidth of the acquired spectral data; the number of acquisition points is obtained based on the number of points of the acquired spectral data.

[0052] Among them, since SpecWidth is inversely proportional to dwelltime, that is, spectral width = 1 / sampling interval time, (SpecWidth = 1 / dwelltime), then the sampling interval time dwelltime = 1 / SpecWidth. The number of acquisition points is based on the number of points of the acquired spectral data. For example, the number of acquisition points is 1024 point data.

[0053] This solution uses the same dwelltime as the simulated data, and the frequency-domain bandwidth of the generated fitting model is the same as that of the acquired data, ensuring the minimization of the model baseline.

[0054] Step S17: Based on the time-domain and frequency-domain spectral fitting function, perform parameter fitting and solution according to the extended spectrum to obtain the fitting parameters and the fitting curve.

[0055] In one embodiment, the spectrum after baseline extension is input into a spectrum fitting function, and parameter fitting is solved using the TDFD fitting method to obtain fitting parameters and a fitting curve.

[0056] To better illustrate the above-mentioned magnetic resonance spectrum fitting method, the present invention provides the following specific embodiments.

[0057] Embodiment 1: Cr2 spectrum fitting method. Figure 2 It is a schematic flow diagram of the Cr2 spectrum fitting method in this embodiment.

[0058] The single-voxel head 1H spectrum data collected using a 3.0T magnetic resonance instrument, with the acquisition bandwidth SpecWidth = 2kHz, TE = 20ms, the number of sampling points = 1024, and the interpolation multiple = 4. After Fourier transform of the collected spectrum data, the entire frequency spectrum range is (12.5269 ~ -3.1250) ppm, but the spectral peaks of interest are mainly concentrated in the range of (4.4 ~ 0.0) ppm. Therefore, in the post-processing step, first, the spectrum data is truncated. Next, it can be considered that the range of (4.4 ~ 0.0) ppm is the entire spectrum range, corresponding to 1151 sampling points. Then, the frequency domain data is subjected to phase correction and chemical shift correction, and finally, the following spectrum curve fitting steps are performed.

[0059] The steps for fitting the Cr2 (Creatine spectral peak, Cr2 chemical shift = 3.193 ppm, reference water peak chemical shift = 4.7 ppm) spectral peak are as follows.

[0060] The first step is to perform Fourier transform on the collected spectrum data and obtain the real part data of the frequency domain spectrum after correction;

[0061] The second step is that the theoretical chemical shift position of the Cr2 spectral peak is 3.193 ppm. Assume that the bottom width of the Cr2 spectral peak is 0.2 ppm, that is, a 0.2 ppm frequency range is selected to generate a limited spectrum. The selection principle is symmetric about the theoretical position of the spectral peak at 3.193 ppm. The selection range of the Cr2 limited spectral peak is (3.193 + 0.1, 3.193 – 0.1) ppm;

[0062] The third step is to calculate the frequency coordinate indices of the left and right endpoints of the Cr2 limited spectrum relative to the entire frequency spectrum, which are used to determine the left and right positions of the spectrum baseline extension, that is, the corresponding number of points for the endpoints of 3.193 + 0.1 and 3.193 - 0.1 are Xleft = 997 and Xright = 1050;

[0063] The fourth step is to generate a limited spectrum (limitedspectrum) from the real part data according to the frequency coordinate indices obtained in the third step;

[0064] Step 5: Set the spectral baseline extension value. Take the zero value (0.0) as the spectral baseline extension value; in spectral post-processing, assuming that the spectrum has completed post-processing steps such as phase correction and baseline correction, the spectrum presents an absorption line shape, that is, the spectral peaks are completely symmetric. At this time, the spectral baseline is relatively flat, so the spectral baseline extension value is set to 0.0;

[0065] Step 6: According to the entire spectral range (4.4 - 0.0) ppm, perform frequency extension to generate the abscissa of the spectral width covering the entire spectral peak range (4.4 - 0.0) ppm, and at the same time generate a preliminary extended spectrum with a baseline of zero value; then, according to the frequency coordinate indices (Xleft = 997 and Xright = 1050) calculated in Step 3, fill the spectral data within the limited range (Xright - Xleft = 1050 - 997 = 53 data points) into the corresponding range (Xleft to Xright) of the extended spectrum to complete the spectral baseline extension;

[0066] Step 7: Set the sampling interval time of the spectral fitting function dwelltime = 1 / SpecWidth = 0.0005 s and the number of points N = 1151;

[0067] Step 8: Input the abscissa of the entire spectral peak range and the spectrum after baseline extension into the spectral fitting function, and use the TDFD fitting method to perform parameter fitting and solution to obtain the fitting parameters and the fitting curve.

[0068] By using the improved TDFD fitting method to fit each spectral peak one by one, and superimposing all the estimated fitting curves, the final fitting curve is obtained. The data to be fitted (Before), the fitting curve (After), and the residual signal (Residual) are shown in Figure 3 the figure. From the fitting curve results, the peak height, peak width, and peak position of the fitting curve obtained by the improved TDFD fitting method are basically consistent with the spectral curve, and the fitting error is small.

[0069] In this embodiment, this patent uses the same dwelltime as the simulated data, and the frequency domain bandwidth of the generated fitting model is also the same as the acquired data. Therefore, during the data fitting process, it is necessary to perform baseline zero value extension on the spectral peaks of interest, which is the same as the spectral peak range of the acquired data. The advantage of doing this is that by baseline extension, the number of points of the spectral peaks to be fitted is increased, the difficulty of spectral peak range selection is reduced, and it is not likely to cause overfitting or deviation of the spectral line half-height width due to too small a range selection. The influence of the baseline is reduced; the extended spectrum after extension is fitted, thereby improving the accuracy of the spectral fitting parameters.

[0070] Similar to the principle of the above embodiments, the present invention provides a magnetic resonance spectroscopy fitting system.

[0071] The following provides specific embodiments in conjunction with the accompanying drawings:

[0072] As Figure 4 shows a schematic structural diagram of a magnetic resonance spectroscopy fitting system in an embodiment of the present invention.

[0073] The system includes:

[0074] A Fourier transform module 41, configured to perform a Fourier transform on the collected spectroscopy data and obtain the real part data of the corrected frequency-domain spectroscopy;

[0075] A finite frequency range selection module 42, connected to the Fourier transform module 41, for selecting a finite frequency range of the spectroscopy of interest based on the theoretical chemical shift position of the spectral peak of interest;

[0076] A frequency index determination module 43, connected to the finite frequency range selection module 42, for determining the frequency coordinate index data of the finite spectroscopy relative to the entire spectrum based on the finite frequency range of the spectroscopy of interest; wherein, the frequency coordinate index data includes: the frequency coordinate indices corresponding to the left and right endpoints of the finite spectroscopy respectively for the entire spectrum;

[0077] A finite spectroscopy generation module 44, connected to the frequency index determination module 43, for generating a corresponding finite spectroscopy from the real part data based on the frequency coordinate index data;

[0078] A frequency expansion module 45, connected to the finite spectroscopy generation module 44, for expanding the frequency of the finite spectroscopy according to the spectral range corresponding to the collected spectroscopy data based on the set spectroscopy baseline expansion value and the frequency coordinate index data to obtain a corresponding expanded spectroscopy;

[0079] A function setting module 46, connected to the frequency expansion module 45, for setting the sampling interval time and the number of sampling points corresponding to the collected spectroscopy data for the time-domain and frequency-domain spectroscopy fitting function;

[0080] A spectroscopy fitting module 47, connected to the function setting module 46, for performing parameter fitting and solution based on the time-domain and frequency-domain spectroscopy fitting function according to the expanded spectroscopy to obtain fitting parameters and a fitting curve.

[0081] It should be noted that it should be understood Figure 4The division of each module in the system embodiment is only a division of logical functions. In actual implementation, it can be fully or partially integrated into a physical entity, or physically separated. And these units can all be implemented in the form of software called by processing elements; they can all be implemented in the form of hardware; or some units can be implemented in the form of software called by processing elements and some units can be implemented in the form of hardware.

[0082] Since the implementation principle of the magnetic resonance spectroscopy fitting system has been described in the foregoing embodiments, it will not be repeated here.

[0083] In one embodiment, the sampling interval time is calculated based on the acquisition bandwidth of the acquired spectroscopy data; the number of acquisition points is obtained based on the number of points of the acquired spectroscopy data.

[0084] In one embodiment, the spectroscopy baseline extension value is set to zero.

[0085] In one embodiment, the selection of the limited frequency range of the spectroscopy of interest based on the theoretical chemical shift position of the spectroscopy peak of interest includes: selecting a limited frequency range of the spectroscopy of interest that is symmetric left and right based on the theoretical chemical shift position of the spectroscopy peak of interest and the selected frequency range.

[0086] In one embodiment, the frequency extension of the limited spectroscopy based on the set spectroscopy baseline extension value and the frequency coordinate index data according to the spectral range corresponding to the acquired spectroscopy data to obtain the corresponding extended spectroscopy includes: performing frequency extension on the limited spectroscopy based on the set spectroscopy baseline extension value and the spectral range of the acquired spectroscopy data to generate a preliminary extended spectroscopy with the abscissa value of the entire spectral range as the spectral width and the spectroscopy baseline extension value as the baseline; filling the limited range spectroscopy data into the corresponding range of the preliminary extended spectroscopy based on the frequency coordinate index data to obtain the corresponding extended spectroscopy.

[0087] In one embodiment, the Fourier transform of the acquired spectroscopy data and obtaining the real part data of the corrected frequency domain spectroscopy includes: performing Fourier transform on the acquired spectroscopy data to obtain the preliminary real part data of the frequency domain spectroscopy; performing phase correction and chemical shift correction on the preliminary real part data of the frequency domain spectroscopy to obtain the real part data of the frequency domain spectroscopy.

[0088] As Figure 5 Show the structural schematic diagram of the magnetic resonance spectroscopy fitting terminal 50 in the embodiment of the present invention.

[0089] The magnetic resonance spectroscopy fitting terminal 50 includes: a memory 51 and a processor 52. The memory 51 is used to store a computer program; the processor 52 runs the computer program to implement as Figure 2 The magnetic resonance spectroscopy fitting method described above.

[0090] Optionally, the number of the memories 51 can each be one or more, and the number of the processors 52 can each be one or more, and Figure 5 only one is taken as an example herein.

[0091] Optionally, the processor 52 in the magnetic resonance spectroscopy fitting terminal 50 will load instructions corresponding to the processes of one or more application programs into the memory 51 according to the steps as Figure 1 described, and the processor 52 will run the application programs stored in the first memory 51, so as to implement various functions in Figure 2 the magnetic resonance spectroscopy fitting method as described.

[0092] Optionally, the memory 51 may include but is not limited to high-speed random access memory and non-volatile memory. For example, one or more disk storage devices, flash memory devices or other non-volatile solid-state storage devices; the processor 52 may include but is not limited to a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0093] Optionally, the processor 52 may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0094] The present invention also provides a computer-readable storage medium storing a computer program, and when the computer program runs, it implements as Figure 1The magnetic resonance spectroscopy fitting method shown. The computer-readable storage medium may include, but is not limited to, floppy disks, optical disks, CD-ROMs (Compact Disc Read-Only Memories), magneto-optical disks, ROMs (Read-Only Memories), RAMs (Random Access Memories), EPROMs (Erasable Programmable Read-Only Memories), EEPROMs (Electrically Erasable Programmable Read-Only Memories), magnetic cards or optical cards, flash memories, or other types of media / machine-readable media suitable for storing machine-executable instructions. The computer-readable storage medium may be a product not connected to a computer device or a component already connected to and used by a computer device.

[0095] In summary, for the magnetic resonance spectroscopy fitting method, system, and terminal of the present invention, the real part data of the frequency-domain spectrum is obtained by performing a Fourier transform on the collected spectrum data, a limited frequency range of the spectrum of interest is selected, the frequency coordinate index data relative to the entire spectrum is then determined, and a corresponding limited spectrum is generated from the real part data; based on the set spectrum baseline expansion value and the frequency coordinate index data, the limited spectrum is frequency-expanded, the sampling interval time and the number of acquisition points of the time-domain and frequency-domain spectrum fitting function are set, and finally the expanded spectrum is fitted. The present invention uses the same sampling interval time (dwell time) as the collected data to construct the time-domain and frequency-domain spectrum fitting function, ensuring the minimization of the baseline; before fitting, artificial spectrum frequency expansion and spectrum baseline expansion are performed so that the range of the expanded spectrum is equal to the entire spectrum range; the influence of the baseline is reduced by setting the spectrum baseline expansion value; the expanded spectrum after expansion is fitted, thereby improving the accuracy of the spectrum fitting parameters. Therefore, the present invention effectively overcomes various drawbacks in the prior art and has high industrial utilization value.

[0096] The above embodiments are only used to exemplarily illustrate the principles and effects of the present invention, rather than to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for magnetic resonance spectroscopy fitting, characterized in that, the method comprises: Performing Fourier transform on the collected spectral data and obtaining the real part data of the corrected frequency-domain spectrum; Selecting a finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest; Based on the finite frequency range of the spectrum of interest, determining the frequency coordinate index data of the finite spectrum relative to the entire spectrum; wherein, the frequency coordinate index data includes: the frequency coordinate indices corresponding to the left and right endpoints of the finite spectrum in the entire spectrum respectively; Generating a corresponding finite spectrum from the real part data based on the frequency coordinate index data; Based on the set spectral baseline extension value and the frequency coordinate index data, performing frequency extension on the finite spectrum according to the spectral range corresponding to the collected spectral data to obtain a corresponding extended spectrum; Setting the sampling interval time and the number of sampling points corresponding to the collected spectral data for the time-domain and frequency-domain spectral fitting function; Based on the time-domain and frequency-domain spectral fitting function, performing parameter fitting and solving according to the extended spectrum to obtain fitting parameters and a fitting curve; wherein, the performing frequency extension on the finite spectrum according to the spectral range corresponding to the collected spectral data based on the set spectral baseline extension value and the frequency coordinate index data to obtain a corresponding extended spectrum includes: Performing frequency extension on the finite spectrum based on the set spectral baseline extension value and the spectral range of the collected spectral data, generating a preliminary extended spectrum with the abscissa value of the entire spectral range and the baseline being the spectral baseline extension value; Based on the frequency coordinate index data, filling the finite-range spectral data into the corresponding range of the preliminary extended spectrum to obtain a corresponding extended spectrum.

2. The method for magnetic resonance spectroscopy fitting according to claim 1, characterized in that, the sampling interval time is calculated based on the acquisition bandwidth of the collected spectral data; the number of sampling points is obtained based on the number of points of the collected spectral data.

3. The method for magnetic resonance spectroscopy fitting according to claim 1, characterized in that, the selecting a finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest includes: Selecting a left-right symmetric finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest and the selected frequency range.

4. The method for magnetic resonance spectroscopy fitting according to claim 1, characterized in that, setting the spectral baseline extension value to zero.

5. The method for magnetic resonance spectroscopy fitting according to claim 1, characterized in that, the performing Fourier transform on the collected spectral data and obtaining the real part data of the corrected frequency-domain spectrum includes: Performing Fourier transform on the collected spectral data to obtain the preliminary real part data of the frequency-domain spectrum; Performing phase correction and chemical shift correction on the preliminary real part data of the frequency-domain spectrum to obtain the real part data of the frequency-domain spectrum.

6. A magnetic resonance spectroscopy fitting system, characterized in that, the system comprises: A Fourier transform module for performing Fourier transform on the collected spectral data and obtaining the real part data of the corrected frequency-domain spectrum; A finite frequency range selection module, connected to the Fourier transform module, selects a finite frequency range of the spectrum of interest based on the theoretical chemical shift position of the spectral peak of interest; A frequency index determination module, connected to the finite frequency range selection module, is used to determine the frequency coordinate index data of the finite spectrum relative to the entire spectrum based on the finite frequency range of the spectrum of interest; wherein, the frequency coordinate index data includes: the frequency coordinate indices corresponding to the left and right endpoints of the finite spectrum in the entire spectrum respectively; A finite spectrum generation module, connected to the frequency index determination module, is used to generate a corresponding finite spectrum from the real part data based on the frequency coordinate index data; A frequency expansion module, connected to the finite spectrum generation module, is used to expand the frequency of the finite spectrum based on the set spectral baseline expansion value and the frequency coordinate index data according to the spectrum range corresponding to the collected spectral data to obtain a corresponding expanded spectrum; A function setting module, connected to the frequency expansion module, is used to set the sampling interval time and the number of sampling points corresponding to the collected spectral data of the time-domain and frequency-domain spectral fitting function; A spectral fitting module, connected to the function setting module, performs parameter fitting and solution based on the time-domain and frequency-domain spectral fitting function according to the expanded spectrum to obtain fitting parameters and a fitting curve; Wherein, the expanding the frequency of the finite spectrum based on the set spectral baseline expansion value and the frequency coordinate index data according to the spectrum range corresponding to the collected spectral data to obtain a corresponding expanded spectrum includes: Expanding the frequency of the finite spectrum based on the set spectral baseline expansion value and the spectrum range of the collected spectral data to generate a preliminary expanded spectrum with the abscissa value of the entire spectrum range and the baseline of the spectral baseline expansion value; Based on the frequency coordinate index data, filling the finite range spectral data into the corresponding range of the preliminary expanded spectrum to obtain a corresponding expanded spectrum.

7. The magnetic resonance spectrum fitting system according to claim 6, wherein, The sampling interval time is calculated based on the acquisition bandwidth of the collected spectral data; the number of sampling points is obtained based on the number of points of the collected spectral data.

8. The magnetic resonance spectrum fitting system according to claim 6, wherein, The spectral baseline expansion value is set to zero.

9. A magnetic resonance spectrum fitting terminal, wherein, comprises: One or more memories and one or more processors; The one or more memories are used to store computer programs; The one or more processors, connected to the memory, are used to run the computer programs to execute the method according to any one of claims 1-5.

Images