System and method for targeted detection of magnetic resonance signals of glucose and lactic acid molecules in cerebrospinal fluid based on J editing spectrum

Abstract

The invention discloses a system and a method for targeted detection of magnetic resonance signals of glucose and lactic acid molecules in cerebrospinal fluid based on J editing spectrum, and belongs to the technical field of magnetic resonance medicine. Based on the J editing technology, the quantum states of glucose and lactic acid molecules are accurately controlled, and accurate detection of alpha-glucose and lactose magnetic resonance signals in cerebrospinal fluid is achieved. By means of the method, magnetic resonance signals of alpha-glucose and lactose molecules in the brain of the human body can be rapidly measured in a non-invasive and non-radiation mode, and obtained data information has important application value in the aspects of early diagnosis, treatment monitoring and the like of mitochondrial encephalomyopathy, meningitis, Alzheimer's disease and other diseases.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic resonance medicine, and particularly relates to a system and method for targeted detection of magnetic resonance signals of glucose and lactic acid molecules in cerebrospinal fluid based on J-edited spectroscopy. Background Art

[0002] Cerebrospinal fluid in the living body contains various inorganic ions, glucose, trace proteins and a small number of lymphocytes at different concentrations, providing certain nutrients for brain cells and timely clearing the metabolites produced by the brain. Changes in the concentration of metabolites in cerebrospinal fluid are accompanied by various neurological diseases, such as viral encephalitis, mitochondrial encephalomyopathy, Alzheimer's disease, diabetes, bacterial encephalitis and Parkinson's disease, etc. Among these metabolites, glucose and lactic acid are key indicators in cerebrospinal fluid. For example, in patients with bacterial encephalitis, bacteria consume a large amount of glucose in cerebrospinal fluid, and the destruction of the blood-brain barrier limits the entry of glucose, resulting in a significant decrease in glucose in cerebrospinal fluid; the hypoxia of brain tissue caused by bacterial infection and the increase in anaerobic metabolism usually lead to a significant increase in the level of lactic acid in cerebrospinal fluid.

[0003] Collecting cerebrospinal fluid through lumbar puncture has become an important method for routine, biochemical and bacteriological examinations, providing a key basis for the diagnosis of intracranial inflammation, tumors, bleeding and demyelinating diseases of the brain. Currently, this technology has become the main means for detecting the components of cerebrospinal fluid. However, due to its invasive characteristics, lumbar puncture is often accompanied by some complications, such as cerebrospinal fluid leakage, migraine, bleeding, spinal cord injury, etc. In addition, some patients are delayed in diagnosis due to contraindications and cannot undergo lumbar puncture detection, such as patients with high intracranial pressure, lumbar deformity, critically ill shock patients. Magnetic Resonance Spectroscopy (MRS) is a technology for non-invasive detection of the types, structures, contents and spatial distributions of metabolites in living tissue organs. Due to its non-invasive and highly sensitive advantages, it is one of the most direct and effective methods for non-invasive detection of in-vivo metabolism. Glucose in cerebrospinal fluid is divided into two types: α-Glc and β-Glc. Due to their similar chemical structures, their magnetic resonance signals overlap with each other and are difficult to distinguish. In addition, the two groups of magnetic resonance signals of α-Glc and β-Glc are close to the water peak, which causes conventional 1 HMRS methods to often interfere with these two groups of signals during the process of water peak suppression. The signal of lactic acid (Lac) molecules is easily overlapped with the signals of molecules such as proteins and lipids in cerebrospinal fluid. Conventional 1 H MRS technology is difficult to simultaneously achieve targeted detection of glucose and Lac signals.

[0004] The patent application "A method and its application for differentiating tuberculous meningitis and viral meningitis based on nuclear magnetic resonance technology" (Publication No.: CN105943048B) provides a technical solution for analyzing the results of cerebrospinal fluid of a patient to be tested detected by nuclear magnetic resonance, so as to determine whether the tested patient is or is a candidate for a patient with tuberculous meningitis, but it is also impossible to achieve simultaneous targeted detection of glucose and lactate molecular signals. Summary of the Invention

[0005] To overcome the deficiencies of the prior art, the present invention proposes a system and method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy, which is a method for targeted detection of glucose and lactate molecules in cerebrospinal fluid using J-edited technology for non-diagnostic purposes. The quantum states of α-glucose and lactate molecules are simultaneously manipulated using J-edited technology, and while efficiently suppressing the water peak, the signals of α-glucose and lactate molecules are targeted for detection. Experiments prove that this method has the advantages of being fast and non-invasive.

[0006] To achieve the above technical objectives, the technical solutions implemented by the present invention are as follows: As a first aspect of the present invention, it lies in providing a system for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy, including: An acquisition module for acquiring magnetic resonance images; the magnetic resonance images can be taken from ex vivo samples or organisms; A pulse sequence application module for applying a pulse sequence and displaying a magnetic resonance spectrum; Among them, information transmission is realized between the acquisition module and the pulse sequence application module through a communication method; The pulse sequence application module includes: a signal suppression module, a signal selection module, and a magnetic resonance spectrum module; among them, the signal suppression module mainly includes two parts: an outer volume suppression (OVS) module and a water suppression (WS) module; The signal selection module includes a saturation pulse and a gradient pulse; The magnetic resonance spectrum module includes several slice selection pulses and gradient pulses.

[0007] Further, the glucose is α-glucose.

[0008] Further, the acquisition module uses a T1 or T2 magnetic resonance weighted sequence to locate the position of in-vivo tissues in the magnetic field and select the region of interest.

[0009] As a second aspect of the present invention, it lies in further proposing a method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy for non-diagnostic purposes, and the method includes: Step i: Suppress the water signal in cerebrospinal fluid using water suppression technology; Step ii: Further suppress the signal of water molecules using the saturation pulse in J-editing technology, and precisely manipulate the quantum state evolution of the spin systems of glucose and lactate molecules; Step iii: Use slice selection pulses and gradient pulses to achieve targeted detection of the signals of glucose and lactate molecules in the region of interest, and obtain the magnetic resonance signals of glucose and lactate molecules.

[0010] Specifically, the present invention designs a specific pulse sequence according to the spin coupling characteristics and chemical shifts between protons in α-glucose and lactate molecules; this pulse sequence mainly consists of "signal suppression", "signal selection" and "magnetic resonance spectroscopy" modules in terms of function. The signal suppression module mainly includes an outer volume suppression (OVS) and a water suppression (WS) part. The signal selection module mainly consists of two saturation pulses with specific frequencies and gradient pulses. The magnetic resonance spectroscopy module consists of multiple slice selection pulses and gradient pulses.

[0011] In the embodiment of the present invention, in step i, the suppression of signals outside the region of interest is achieved using outer volume suppression; the outer volume suppression includes 8 saturation pulses, each saturation pulse has a time of 8 ms, and the amplitudes of the saturation pulses are all 160 Hz.

[0012] In the embodiment of the present invention, in step ii, the echo time is set between 90 ms and 130 ms, and 180-degree slice selection pulses and saturation pulses resonant with the water peak are used; Preferably, two saturation pulses are used, both with a Gaussian shape, a time of 15 ms, and a frequency center of 4.7 ppm.

[0013] In the embodiment of the present invention, in step iii, three sinc-type slice selection pulses are used, and the times of the slice selection pulses are 2.5 ms, 5 ms, and 5 ms respectively, and the flip angles are 90 degrees, 180 degrees, and 180 degrees respectively.

[0014] In the embodiment of the present invention, in step iii, the position of the biological living body in the magnetic field is located using a conventional T1 or T2 weighted sequence, and the region of interest is selected.

[0015] In the embodiment of the present invention, in step iii, the magnetic resonance signals of glucose and lactate molecules include their J-coupling values, the chemical shifts of protons on the methyl group, and the signal intensities.

[0016] The present invention provides a system for targeted detection of glucose and lactate molecular magnetic resonance signals in cerebrospinal fluid based on J-edited spectroscopy, and implements the method for targeted detection of glucose and lactate molecular magnetic resonance signals in cerebrospinal fluid based on the J-edited spectroscopy method.

[0017] The beneficial effects of the present invention are as follows: 1. The present invention provides a system for targeted detection of glucose and lactate molecular magnetic resonance signals in cerebrospinal fluid based on J-edited spectroscopy. Based on magnetic resonance technology, a significant feature and innovation of this system, which is different from other previous magnetic resonance spectroscopy techniques, lies in that: by using the J-edited technology, the signals of α-glucose and lactate molecules in the in-vivo cerebrospinal fluid are targeted and detected, and it is expected to replace lumbar puncture clinically and become a routine clinical examination.

[0018] 2. The method of the present invention can quickly, non-invasively, and non-radiatively measure the magnetic resonance signals of α-glucose and lactate molecules in the body, and has good accuracy, sensitivity, and stability; it has important application value in aspects such as biology and medicine, and provides a new detection idea.

[0019] 3. The data information obtained based on the detection method of the present invention has important application value in the early diagnosis, treatment monitoring, etc. of diseases such as mitochondrial encephalomyopathy, meningitis, and Alzheimer's disease. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following described drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 They are respectively schematic diagrams of the molecular structures of Lac, α-Glc, and β-Glc involved in the present invention; among them, (a) is the structural formula of the lactate molecule, (b) is the structural formula of α-Glc, and (c) is the structural formula of β-Glc.

[0022] Figure 2 It is the specific implementation flowchart of the method of the present invention.

[0023] Figure 3 It is a schematic diagram of the pulse sequence for accurately observing the magnetic resonance signals of α-Glc and Lac in cerebrospinal fluid according to the present invention. Among them, G x , G y and G z respectively represent the pulse gradient channels in the x, y, and z directions, 90 x , 180 y , 180 y90, 180, 180, and x , y , y are the flip angle and phase of the pulses used for the slice selection pulse, respectively.

[0024] Figure 4 is a schematic diagram of the main steps of the specific embodiment of the present invention.

[0025] Figure 5 is the detection result of the water film sample in Example 1 of the present invention; among them, (a) is the conventional T1-weighted image of the water film sample, the upper part of (b) is the conventional magnetic resonance spectroscopy, and the lower part of (b) is obtained by using Figure 3 pulses to obtain a magnetic resonance spectroscopy; among them, α-Glc refers to the magnetic resonance signal of the protons on the methylene of α-Glc near 5.2 ppm.

[0026] Figure 6 is the detection result of the 12-year-old subject with mitochondrial encephalomyopathy in Example 2 of the present invention; among them, (a) is the conventional T1-weighted image of the patient, the upper part of (b) is the conventional magnetic resonance spectroscopy of the subject, and the lower part of (b) is obtained by using Figure 3 pulses to obtain a magnetic resonance spectroscopy.

[0027] Figure 7 is the detection result of the 55-year-old subject with ventricular dilation in Example 3 of the present invention; among them, (a) is the conventional T1-weighted image, the upper part of (b) is the conventional magnetic resonance spectroscopy of the subject, and the lower part of (b) is obtained by using Figure 3 pulses to obtain a magnetic resonance spectroscopy. Specific Embodiment

[0028] The present invention will be further described below in conjunction with specific embodiments and drawings. The processes, conditions, experimental methods, etc. for implementing the present invention are all common knowledge and well-known common sense in the art except for the specifically mentioned content below, and the present invention has no particularly restricted content.

[0029] Figure 1 are schematic diagrams of the molecular structures of Lac, α-Glc, and β-Glc involved in the present invention; among them, (a) is the structural formula of lactic acid molecule, (b) is the structural formula of α-Glc, and (c) is the structural formula of β-Glc. Since the structures of α-Glc and β-Glc are similar, the nuclear magnetic resonance signals of the two overlap with each other in cerebrospinal fluid and are difficult to distinguish. In the prior art, it is also difficult to accurately detect lactic acid molecules.

[0030] The present invention provides a system and method for targeted detection of the magnetic resonance signals of glucose and lactic acid molecules in cerebrospinal fluid based on J-edited spectroscopy, and the J-edited technology can be used to achieve targeted detection of α-glucose and lactic acid molecules in cerebrospinal fluid.

[0031] Example 1, a system for targeted detection of glucose and lactate molecular magnetic resonance signals in cerebrospinal fluid based on J-edited spectroscopy It includes an acquisition module for acquiring magnetic resonance images of the brain; A pulse sequence application module for applying a pulse sequence and displaying magnetic resonance spectroscopy; Among them, information transmission is achieved through a communication method between the acquisition module and the pulse sequence application module; The pulse sequence application module includes: a "signal suppression" module, a "signal selection" module, and a "magnetic resonance spectroscopy" module; among them, the signal suppression module mainly includes two parts: an outer volume suppression (OVS) module and a water suppression (WS) module; The signal selection module includes two saturation pulses and gradient pulses at specific frequencies; The magnetic resonance spectroscopy module includes multiple slice selection pulses and gradient pulses.

[0032] In one or more embodiments of the present invention, the acquisition module uses T1 or T2 magnetic resonance weighted sequences to locate the position of internal tissues in the magnetic field and select the region of interest.

[0033] In one or more embodiments of the present invention, the water suppression module is used to suppress the signal of water molecules in the selected region of interest. The VAPOR (VAriable Power radiofrequency pulses with Optimized Relaxation delays) technology composed of multiple radiofrequency pulses, evolution time, and gradient pulses is adopted. This method includes multiple small-angle radiofrequency pulses and optimized evolution time, and can have a narrow suppression range in the spectrum. While suppressing the water peak, it avoids the influence on the α-glucose signal. In the embodiments of the present invention, 8 radiofrequency pulses are adopted, and the flip angle of each pulse is: α, α, 1.78α, α, 1.59α, α, 1.78α, 1.78α, where α is 80 degrees; the evolution time between pulses is respectively: 150 ms, 100 ms, 122 ms, 105 ms, 102 ms, 61 ms, 67 ms, 14 ms.

[0034] In addition, the outer volume suppression module is nested in the VAPOR pulse to suppress the magnetic resonance signal outside the region of interest, while ensuring a short recovery time (TR) and water peak suppression effect, and as much as possible ensuring that the selected voxel is cerebrospinal fluid rather than brain tissue. In the present invention, there are 8 saturation pulses in the outer volume suppression module, and the time of each saturation pulse is 8 ms.

[0035] A method for targeted detection of glucose and lactate molecular magnetic resonance signals in cerebrospinal fluid based on J-edited spectroscopy, as Figure 2 shown, the method comprises the following steps: Step i: Suppress the water signal in cerebrospinal fluid using water suppression technology; Step ii: Further suppress the signal of water molecules using the saturation pulse in J-edited technology, and precisely control the quantum state evolution of the spin systems of α-glucose and lactate molecules; Step iii: Use the slice selection pulse and gradient pulse to achieve targeted detection of glucose and lactate signals in the region of interest, and obtain the magnetic resonance signals of glucose and lactate molecules.

[0036] Specifically, the present invention designs a specific pulse sequence according to the spin coupling characteristics and chemical shifts between protons in α-glucose and lactate molecules; this pulse sequence mainly consists of "signal suppression", "signal selection" and "magnetic resonance spectroscopy" modules in function, wherein the signal suppression module mainly includes an outer volume suppression (OVS) and a water suppression (WS) part; the signal selection module mainly consists of two saturation pulses with specific frequencies and gradient pulses, where the gradient pulses refer to Figure 3 six trapezoidal gradient pulses near the two saturation pulses in, their amplitudes can range from 5 mT / m to 40 mT / m, and the time can range from 1 ms to 5 ms. The amplitudes and times of the trapezoidal gradient pulses adopted in the embodiments of the present invention are 15 mT / m and 2.5 ms respectively; the magnetic resonance spectroscopy module consists of multiple slice selection pulses and gradient pulses.

[0037] In one or more embodiments of the present invention, in step i, in order to suppress the water peak while avoiding affecting the α-glucose signal, the present invention adopts the VAPOR (VAriablePower radiofrequency pulses with Optimized Relaxation delays) technology composed of multiple radiofrequency pulses, evolution time, and gradient pulses to suppress the signal of water molecules in the selected region of interest. In the present invention, 8 radiofrequency pulses are adopted, and the flip angle of each pulse is: α, α, 1.78α, α, 1.59α, α, 1.78α, 1.78α, where α is 80 degrees; the evolution times between pulses are respectively: 150 ms, 100 ms, 122 ms, 105 ms, 102 ms, 61 ms, 67 ms, 14 ms. The time of the 1st - 3rd gradient pulses in VAPOR is 4 ms each, and the amplitude is 15 mT / m; the time of the 4th - 6th gradient pulses is 3 ms each, and the amplitude is 10 mT / m; the time of the 6th - 10th gradient pulses is 2 ms each, and the amplitude is 10 mT / m; the time of the 11th - 13th gradient pulses is 2 ms each, and the amplitude is 8 mT / m; in addition, the outer volume suppression module is nested in the VAPOR pulses to suppress the magnetic resonance signal outside the region of interest while ensuring a short recovery time (Recovery Time, TR) and water peak suppression effect. In the present invention, there are 8 saturation pulses in the outer volume suppression module, the time of each saturation pulse is 8 ms, and the amplitude of the saturation pulses is 160 Hz.

[0038] In step ii, the present invention simultaneously considers the evolution of the four-spin system of lactic acid molecules and the seven-spin system of α-glucose. Since VAPOR and OVS in step i significantly suppress the signal of water molecules in the cerebrospinal fluid voxel. However, the concentration of α-glucose in the cerebrospinal fluid is only about one ten-thousandth of that of water molecules. Therefore, the residual water signal caused by VAPOR water suppression is usually much higher than that of α-glucose. To further suppress water molecules, the present invention aligns the frequency of the saturation pulse in the signal selection module with the water peak for further suppression of the residual water peak. The quantum state evolution of the α-glucose seven-spin system is as follows: Under the action of radio frequency pulses and gradient pulses, the quantum state of the α-glucose molecule seven-spin system is transformed from the thermal equilibrium state S1z + S2z + S3z + S4z + S5z + S6z + S7z to S1x, and other signals are damaged by the saturation pulse and gradient pulse. At this time, the signal of α-glucose near 5.25 ppm is a positive doublet, where Sjx and Sjz (j = 1~7) refer to the product operators of the jth nuclear spin of the α-glucose molecule in the x and z directions respectively; in addition, under the action of pulses with a long echo time, the fat signal is suppressed; generally speaking, through J-editing technology, while suppressing the water peak and other metabolite signals, the targeted detection of lactic acid molecules and α-glucose in the cerebrospinal fluid is achieved simultaneously.

[0039] In step ii, the range of the echo time (TE) is set between 90 ms and 130 ms. Under the action of radio frequency pulses and gradient pulses, the quantum state of lactic acid molecules will be transformed from the thermal equilibrium state I1z + I2z + I3z + I4z to - (I1x + I2x + I3x + I4x), where is the transfer efficiency of lactic acid molecules from the thermal equilibrium state to the single quantum state. At this time, the signal of lactic acid molecules near 1.33 ppm is an inverted doublet, where Ijx and Ijz (j = 1~4) refer to the product operators of the jth nuclear spin of lactic acid molecules in the x and z directions respectively.

[0040] In one or more embodiments of the present invention, in step ii, under the action of the pulse sequence with a long TE, the signals of fat and protein molecules are suppressed by spin-spin relaxation; generally speaking, through J-editing technology, while suppressing the water peak and fat signal, the targeted detection of lactic acid molecules and α-glucose is achieved.

[0041] In one or more embodiments of the present invention, in step ii, the saturation pulse for water peak resonance refers to that the coverage range of the saturation pulse is centered on the chemical shift of water molecules, such that the spin system of the molecules evolves under the action of the saturation pulse. The saturation pulse may be composed of one or more long-duration hard pulses or shaped pulses. The frequencies of multiple saturation pulses are all set near the resonance frequency of water molecules for further suppressing the signal of water molecules. To avoid affecting the signal of α-glucose, within a specific TE time, the time of the saturation pulse for water peak resonance should be as long as possible. The present invention uses two saturation pulses, both with a Gaussian shape, a time of 15 ms each, and a frequency center of 4.7 ppm.

[0042] In one or more embodiments of the present invention, in step iii, the present invention uses three sinc-type slice selection pulses, with the times of the slice selection pulses being 2.5 ms, 5 ms, and 5 ms respectively, and the flip angles being 90 degrees, 180 degrees, and 180 degrees respectively; the time of the gradient pulse is the same as that of the slice selection pulse.

[0043] In one or more embodiments of the present invention, in step iii, in order to detect the magnetic resonance signals of α-glucose and lactate molecules in cerebrospinal fluid, the position of a biological living body in a magnetic field can be located using a conventional T1 or T2 weighted sequence. This part of knowledge is well-known in the field, and the present invention will not elaborate further.

[0044] In one or more embodiments of the present invention, in step iii, the magnetic resonance signals of α-glucose and lactate molecules include the J-coupling value ( =7.0±0.2 Hz) and chemical shift ( =5.2±0.3 ppm) of the methylene group of α-glucose near 5.2 ppm, the J-coupling value ( =6.9±0.2 Hz) and chemical shift ( =1.33±0.3 ppm) of the proton on the methyl group of lactate molecules near 1.33 ppm, and their signal intensities.

[0045] In step iii, the main step flow of the implementation method is as Figure 4 shown: 1. Use a T1 or T2 magnetic resonance weighted sequence to locate the position of in-vivo tissues in a magnetic field and select the region of interest. Specifically, collect conventional T1 or T2 weighted images of the human brain or caudal vertebra of a biological living body, and select the region of interest at the position of cerebrospinal fluid.

[0046] 2. Apply the Figure 3 shown pulses to accurately observe the magnetic resonance signals of α-glucose and lactate molecules in the cerebrospinal fluid of an actual organism.

[0047] Experimental Example 1 Experimental subjects: A mixed solution of α-Glc and Lac, with their concentrations both being 20 millimoles per liter and the sample volume being 45 milliliters. Measuring instrument: Siemens 3T Skyra nuclear magnetic resonance instrument, and the detection coil used is a Siemens 64-channel head and neck combined coil.

[0048] Measuring method: Figure 3 The pulse sequence shown. The experimental steps are as follows: 1. Use the conventional T1-weighted sequence to locate the position of the water film sample in the magnetic field and select the area of the water film sample to be measured. The magnetic resonance image of the water film and the selected area are shown in Figure 5 Figure (a). 2. Apply the Figure 3 pulse sequence shown. The specific experimental parameters are as follows: The spin recovery time (Repetition Time, TR) is 2000 ms, the echo time (Echo Time, TE) is 110 ms, the number of averages is 128, the flip angle is 90°, the size of the region of interest is 30×10×10 cubic millimeters, the saturation pulse in the signal selection module is Gaussian type, the time is 15000 microseconds, and the radio frequency center is 4.70 ppm. During the experiment, the center frequency of the saturation pulse and the echo time can be fine-tuned to optimize the nuclear magnetic resonance signals of α-glucose and lactate molecules.

[0049] 3. The experimental results are shown in Figure 5 Figure, where Figure 5 Figure (a) is the T1-weighted nuclear magnetic resonance image of the mixed solution of α-glucose and lactate molecules; Figure 5 Figure (b) is the nuclear magnetic resonance spectra of the conventional sequence (top) and the sequence using the Figure 3 pulse sequence (bottom). It can be seen from the figure that the α-glucose signal near the water peak in the 1H MRS spectrum of the conventional sequence is suppressed, and the α-glucose and β-glucose at other frequencies overlap severely.

[0050] Using the Figure 3 pulse sequence, the 1H MRS spectrum targeting α-glucose is obtained. At this time, the signal of α-glucose is a positive doublet (near 5.2 ppm), while the signals of other metabolites are greatly suppressed, and the signal of lactate molecules is an inverted peak. Experimental Example 2 Experimental subjects: A male patient clinically diagnosed with mitochondrial encephalomyopathy at the age of 12.

[0051] Measuring instrument: Siemens 3T Skyra nuclear magnetic resonance instrument, and the detection coil used is a Siemens 64-channel head and neck combined coil.

[0052] Measuring method: Figure 3The pulse sequence shown The experimental steps are as follows: 1. Use a conventional three-dimensional T1-weighted sequence to acquire magnetic resonance images of the patient's brain, and select the region of interest (cerebrospinal fluid in the brain). The in-vivo brain magnetic resonance image and the region of interest are shown in Figure 6 (a).

[0053] 2. Apply the Figure 3 pulse sequence shown. The specific experimental parameters are as follows: the repetition time (TR) is 2000 ms, the echo time (TE) is 110 ms, the number of averages is 128, the flip angle is 90°, the size of the region of interest is 20×20×20 cubic millimeters, the shape of the saturation pulse in the signal editing module is a Gaussian pulse, the time is 15000 microseconds, and the radiofrequency center is 4.70 ppm. During the experiment, the center frequency and echo time of the saturation pulse can be fine-tuned to optimize the magnetic resonance signals of α-glucose and lactate molecules.

[0054] 3. The experimental results are shown in Figure 6 . Among them, Figure 6 (a) is the T1-weighted magnetic resonance image of the patient and the selected region (cerebrospinal fluid in the brain), Figure 6 on the left of (b) is the magnetic resonance spectrum collected in the region of interest by the conventional sequence (top) and the Figure 3 pulse sequence (bottom). In the 1H MRS spectrum of the conventional sequence, the magnetic resonance signals of α-glucose and β-glucose in the range of 3.0 ppm - 4.5 ppm overlap severely and are difficult to separate. In addition, the α-glucose signal near 5.20 ppm is partially saturated during water suppression, and the lactate molecule signal near 1.33 ppm overlaps with a small amount of lipid and protein signals in the body. In the spectrum of the patient's cerebrospinal fluid collected using the Figure 3 pulse sequence, the magnetic resonance signals of α-glucose and β-glucose in the range of 3.0 ppm - 4.5 ppm are greatly suppressed, the signal near 5.20 ppm can be clearly observed, and the J coupling between the two doublets is similar to that of the water film (both are 7.0 Hz), and the signal of the lactate molecule shows an inverted peak.

[0055] Experimental Example 3 Experimental subject: A 55-year-old male patient clinically diagnosed with ventricular dilation.

[0056] Measuring instrument: Siemens 3T Skyra nuclear magnetic resonance instrument, and the detection coil used is a Siemens 64-channel head and neck combined coil.

[0057] Measuring method: Figure 3 The pulse sequence shown The experimental steps are as follows: 1. Collect magnetic resonance images of the patient's brain using a conventional three-dimensional T1-weighted sequence, and select the region of interest (cerebrospinal fluid in the brain). The in-vivo brain magnetic resonance image and the region of interest are shown in Figure 7 Figure (a). 2. Apply the Figure 3 pulse sequence as shown. The specific experimental parameters are as follows: the repetition time (TR) is 2000 ms, the echo time (TE) is 110 ms, the number of averages is 128, the flip angle is 90°, the size of the region of interest is 20×20×20 cubic millimeters, the shape of the saturation pulse in the signal editing module is a Gaussian pulse, the time is 15000 microseconds, and the radiofrequency center is 4.70 ppm. During the experiment, the center frequency and echo time of the saturation pulse can be fine-tuned to optimize the magnetic resonance signals of α-glucose and lactate molecules.

[0058] 3. The experimental results are shown in Figure 7 Figure. Among them, Figure 7 Figure (a) is the T1-weighted magnetic resonance image of a patient with ventricular dilation and the selected region (cerebrospinal fluid in the brain). Figure 7 On the left side of Figure (b), the top is the conventional sequence and the bottom is the magnetic resonance spectrum collected in the region of interest using the Figure 3 pulse sequence. In the 1H MRS spectrum of the conventional sequence, the magnetic resonance signals of α-glucose and β-glucose in the range of 3.0 ppm - 4.5 ppm overlap severely and are difficult to separate. In addition, the α-glucose signal near 5.20 ppm is partially saturated during the water suppression process, and the lactate molecule signal near 1.33 ppm overlaps with a small amount of lipid and protein signals in the body. In the spectrum of the patient's cerebrospinal fluid collected using the Figure 3 pulse sequence, the magnetic resonance signals of α-glucose and β-glucose in the range of 3.0 ppm - 4.5 ppm are significantly suppressed, the signal near 5.20 ppm can be clearly observed, and the J coupling between the two peaks is similar to that of the water film (both are 7.0 Hz), and the signal of the lactate molecule shows an inverted peak.

[0059] The protection scope of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, the changes and advantages that those skilled in the art can think of are included in the present invention, and the scope of protection is defined by the appended claims.

Claims

1. A system for detecting the magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy, characterized in that: include: An acquisition module, used for acquiring magnetic resonance images; A pulse sequence applying module, used for applying a pulse sequence and displaying a magnetic resonance spectrum; Among them, the acquisition module and the pulse sequence application module realize information transmission through communication; The pulse sequence application module includes: a signal suppression module, a signal selection module and a magnetic resonance spectroscopy module; Wherein, the signal suppression module includes an out-of-volume suppression module and a water suppression module; The signal selection module includes a saturation pulse and a gradient pulse; The magnetic resonance spectroscopy module includes several slice selection pulses and gradient pulses.

2. The system for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 1, characterized in that: The glucose is α-glucose.

3. The system for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 1, characterized in that: The acquisition module uses T1 or T2 magnetic resonance weighted sequences to locate the position of the body tissue in the magnetic field and select the region of interest.

4. A method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy, characterized in that: The steps include: Step i: using water suppression technology to suppress water signals in cerebrospinal fluid; Step ii: Use the saturation pulse in the J-editing technique to further suppress the signal of water molecules and precisely control the quantum state evolution of the spin system of glucose and lactate molecules; Step iii: Use the slice selection pulse and gradient pulse to achieve targeted detection of the glucose and lactic acid molecular signals in the region of interest, and obtain the magnetic resonance signals of the glucose and lactic acid molecules.

5. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 4, characterized in that: In step i, 8 RF pulses were used, and the flip angles of each pulse were: α, α, 1.78α, α, 1.59α, α, 1.78α, 1.78α, where α was 80 degrees; the evolution times between pulses were: 150 ms, 100 ms, 122 ms, 105 ms, 102 ms, 61 ms, 67 ms, and 14 ms, respectively.

6. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 4, characterized in that: In step i, the signal outside the region of interest is suppressed by using extra-volume suppression, which includes 8 saturation pulses, each of which lasts 8 ms and has an amplitude of 160 Hz.

7. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 6, characterized in that: In step ii, the echo time is set between 90 ms and 130 ms, and a 180-degree layer-selective pulse and a saturation pulse of water peak resonance are used; Two saturation pulses were used, both with Gaussian shape, 15 ms duration and frequency centred at 4.7 ppm.

8. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 7, characterized in that: In step iii, three sinc-type layer selection pulses are used, the layer selection pulse times are 2.5 ms, 5 ms and 5 ms, and the flip angles are 90 degrees, 180 degrees and 180 degrees, respectively.

9. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 8, characterized in that: In step iii, the position of the living organism in the magnetic field is located using a conventional T1 or T2 weighted sequence, and a region of interest is selected.

10. The method for targeted detection of magnetic resonance signals of glucose and lactate molecules in cerebrospinal fluid based on J-edited spectroscopy according to claim 9, characterized in that: In step iii, the magnetic resonance signals of glucose and lactic acid molecules include their J coupling values, chemical shifts of protons on methyl groups, and signal intensities.

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