19 results about "Saturation pulse" patented technology

The present invention addresses the problem of reducing dependency on an operator and reducing the influence of a fat signal on a frequency spectrum with high precision. A magnetic resonance data collection device according to an embodiment includes an acquisition unit, a generation unit, and a collection unit. The acquisition unit acquires a specified region of interest. The generation unit generates a pulse sequence for collecting magnetic resonance data multiple times while changing at least one of a collection region and a saturation pulse setting condition based on the region of interest. The collection unit collects a plurality of magnetic resonance data in accordance with the pulse sequence.

The invention relates to a computer-implemented method for acquiring magnetic resonance data with a magnetic resonance device (18), wherein a magnetic resonance sequence is used in which, during an equilibrium state in a sequence segment maintained by regular excitation modules (9, 9a - 9e) with at least one excitation pulse, both a first readout time window (11, 11a - 11e) immediately following an excitation module (9, 9a - 9e) for measuring magnetic resonance data of a free induction decay and second readout time windows (12, 12a - 12e), which are spaced at least the first readout duration of the first readout time window (11, 11a - 11e) from a last excitation module (9, 9a - 9e), which acts as a refocusing module for the penultimate excitation module (9, 9a - 9e), are used for measuring magnetic resonance data of a spin echo. become,wherein, between at least one pair consisting of a starting excitation module (9c) and a final excitation module (9d) that follow one another, a fat saturation module (15) with at least one high-frequency fat saturation pulse (16) is output in the magnetic resonance sequence during a preparation period (14).

To accurately reduce the influence of a fat signal on a spectrum while reducing dependence on an operator.SOLUTION: A magnetic resonance data collection device includes an acquisition unit, a generation unit, and a collection unit. The acquisition unit acquires a designated region of interest. The generating unit generates a pulse sequence for acquiring magnetic resonance data a plurality of times while changing at least one of an acquisition region and a setting condition of a saturation pulse with reference to the region of interest. The collection part collects a plurality of magnetic resonance data according to the pulse sequence.SELECTED DRAWING: Figure 2

The invention provides a respiratory-gating-free free-breathing liver glycogen quantitative magnetic resonance imaging method and system, and the method comprises the steps: applying a chemical exchange saturation transfer imaging sequence to a liver region of a subject, and the imaging sequence comprises saturation pulses of a plurality of saturation frequency deviation points; a radial blade type k-space acquisition strategy is adopted to acquire magnetic resonance signal data, the radial blade type k-space acquisition strategy comprises a plurality of blades, each blade is composed of a group of parallel k-space lines, and different blades are rotationally distributed by taking the k-space center as a rotating shaft; performing image reconstruction on the acquired k space data to obtain magnetic resonance images under different saturation frequency deviations; and performing fitting analysis on the magnetic resonance image by adopting a multi-pool Lorentz model to obtain quantitative information of the liver glycogen. According to the method, the interference of respiratory movement on the CESTMRI data acquisition process can be eliminated, so that the accurate quantification of the liver glycogen in the free respiration state is realized.

The present invention discloses a magnetic resonance molecular imaging method and system for dynamically reading the accumulation of CEST signals. The method includes: applying N CEST saturation pulses for an object to be detected within each repetition time by a magnetic resonance imaging device; after each of the first N-1 CEST saturation pulses, a low-resolution, small-angle reading method is used to read the signal to obtain N-1 first-class signals; after the Nth CEST saturation pulse, a high-resolution, large-angle reading method is used to read the signal to obtain a second-class signal to compensate for the first-class signal, and N saturation-weighted magnetic resonance images of the object to be detected are obtained based on the compensated first and second-class signals. The method can improve the signal-to-noise ratio and robustness of CEST imaging, and can dynamically change according to the N readout signals, with better quantitativeness, such as reducing the influence of tissue longitudinal relaxation (T1) to obtain a proton exchange rate image.

This application discloses a magnetic resonance chemical exchange saturation transfer imaging method, system, device, and storage medium. The method includes: applying a radio frequency saturation pulse for a first preset time to a region to be detected; applying a radio frequency echo pulse to the region to be detected and acquiring several gradient echo signals generated after activation by the radio frequency echo pulse; and using radial sampling to read the gradient echo signals along a preset direction to generate a magnetic resonance image. Through this method, this application effectively shortens the signal acquisition time by using gradient echo readings, effectively suppresses motion artifacts by using radial acquisition, and applies post-processing methods such as fitting to the acquired chemical exchange saturation transfer imaging spectral data to achieve water-lipid signal separation and extract and analyze the target signal.

According to one embodiment, a magnetic resonance data acquisition apparatus includes processing circuitry. The processing circuitry is configured to obtain a designated region of interest. The processing circuitry is configured to generate a pulse sequence for acquiring magnetic resonance data multiple times based on the region of interest while changing at least one of a region for acquisition or a condition of setting a saturation pulse. The processing circuitry is configured to acquire multiple pieces of magnetic resonance data according to the pulse sequence.

A method of acquiring magnetic resonance (MR) data from a subject using a magnetic resonance imaging (MRI) system includes generating, for each of at least one level in the subject, a first pre-saturated RF pulse having a first flip angle, generating, after each first pre-saturated RF pulse, a series of first gradient echo sequences, and calculating a B0 value for each of the at least one level. A second pre-saturated RF pulse having a second flip angle is generated for each of the at least one planes in the subject, then a series of second gradient echo sequences is generated, and B1 is calculated for each of the at least one planes based on the first gradient echo sequences and the second gradient echo sequences.

Methods and systems are provided for automatic placement of at least one saturation band on a medical image, which may direct saturation pulses during a MRI scan. A method may include acquiring a localizer image of an imaging subject, determining a plane mask for the localizer image by entering the localizer image as input to a deep neural network trained to output the plane mask based on the localizer image, generating a saturation band based on the plane mask by positioning the saturation band at a position and an angulation of the plane mask, and outputting a graphical prescription for display on a display device, the graphical prescription including the saturation band overlaid on the medical image.

A bimetallic composite pipe liner collapse detection method based on magnetic saturation pulsed eddy current and signal processing consists of two parts: a pulsed eddy current method based on magnetic saturation and a signal processing method with late correlation coefficient as an adaptive feature quantity. When implementing this method, the outer carbon steel of the bimetallic composite pipe is first magnetized by a magnetic yoke until magnetic saturation, thereby reducing the magnetic resistance between the outer carbon steel and the inner stainless steel, so that the magnetic field and eddy current field generated by the pulsed eddy current can penetrate the outer carbon steel and enter the inner stainless steel. Then, the original pulsed eddy current signal is subjected to low-pass filtering, independent component analysis, and Gaussian filtering to eliminate high-frequency noise respectively. , power frequency interference and random noise, and then the filtered pulse eddy current late signal of the bimetallic composite pipe without liner collapse is used as the reference signal, and the Pearson correlation coefficient of the filtered pulse eddy current late signal of the bimetallic composite pipe to be tested and the reference signal is calculated, and the characteristic quantity is called the late correlation coefficient, and finally the characteristic quantity and the corresponding calibration curve are used to characterize the degree of liner collapse of the bimetallic composite pipe; the method of the present invention proposes an optimized pulse eddy current method and an adaptive characteristic quantity, which realizes the detection of liner collapse of bimetallic composite pipe, and has high theoretical value and engineering application value.

The invention provides a magnetic resonance angiography method and magnetic resonance imaging equipment. The method comprises the following steps: for each magnetic resonance image to be generated in a magnetic resonance image sequence, sequentially generating a layer selection saturation pulse signal and N reversal pulse signals in an imaging area of at least a target object; magnetic resonance signals of tissue in the imaging region are acquired and the magnetic resonance image is generated based on the acquired magnetic resonance signals. The longitudinal magnetization directions of the blood subjected to the second reversal operation in the first time period are negative when the blood is imaged in the imaging area, and the longitudinal magnetization directions of the blood subjected to the second reversal operation in the second time period are positive when the blood is imaged in the imaging area. The display effect of the blood inflow process in the obtained magnetic resonance image sequence is clearer, and a user can be helped to determine the actual condition of blood perfusion into the blood vessel in the imaging area.

The invention belongs to the technical field of biology, and particularly relates to a method for detecting magnetic resonance signals of glutaric acid molecules and application. The method comprises the following steps: firstly, positioning a target area by utilizing a magnetic resonance imaging sequence, and then respectively collecting magnetic resonance spectrograms of EditOn and EditOff states by adopting a water suppression sequence, a volume external suppression sequence and a J editing sequence and setting resonant frequencies of saturated pulses by the J editing sequence; and subtracting the spectrogram acquired in the EditOn state from the spectrogram acquired in the EditOff state to obtain a differential spectrum, so that a glutaric acid signal is selectively excited near 2.2 ppm and a lipid signal is inhibited. A good effect of rapidly and noninvasively measuring the magnetic resonance signal of the glutaric acid molecules in the living body muscle tissue is realized, and the method has important application value in the field of scientific research.

The application provides a magnetic resonance angiography method and a magnetic resonance imaging device, the magnetic resonance angiography method comprising: for each magnetic resonance image to be generated in a magnetic resonance image sequence, sequentially generating a layer selection saturation pulse signal and N inversion pulse signals in a preset time period corresponding to the magnetic resonance image and in at least an imaging region of a target object, the N inversion pulse signals being used for performing a first inversion operation on tissues in the at least imaging region; after or simultaneously with performing the first inversion operation on the tissues in the at least imaging region by using an (N-i+1)th inversion pulse signal, and before performing the first inversion operation on the tissues in the at least imaging region by using an (N-i)th inversion pulse signal, performing a second inversion operation on blood in a labeling region; collecting a magnetic resonance signal of the tissues in the imaging region, and generating the magnetic resonance image. In the above scheme, the total time consumption of the magnetic resonance imaging process is shorter, and the imaging efficiency is significantly improved.

Methods and systems are provided for automatic placement of at least one saturation band on a medical image, which may direct saturation pulses during a MRI scan. A method may include acquiring a localizer image of an imaging subject, determining a plane mask for the localizer image by entering the localizer image as input to a deep neural network trained to output the plane mask based on the localizer image, generating a saturation band based on the plane mask by positioning the saturation band at a position and an angulation of the plane mask, and outputting a graphical prescription for display on a display device, the graphical prescription including the saturation band overlaid on the medical image.

A method for simultaneous imaging and image processing of neuromelanin and nigrosome 1 using 3D multi-echo GRE performed by a computer includes: a step (S120) of acquiring a neuromelanin (NM) image (130) and a multi-echo gradient recalled echo (GRE) brain image with a more enhanced contrast ratio than an MRI image by applying two spatial saturation pulses to a 3D multi-echo GRE; a step (S150) of generating a susceptibility map weighted imaging (SMWI) image (140) for nigrosome 1 (N1) using the 3D multi-echo GRE image acquired in the acquisition step (S120); and an inference step (S170) of analyzing, by a neural network (NN) model, the NM image (130) and the SMWI image (140) to quantify volumes of the neuromelanin (NM) and the nigrosome 1 (N1).

The embodiment of the present application discloses a liquid level detection device and method, the device comprises: a liquid suction needle assembly for contacting the pulse signal generated by the liquid suction needle when the current detection liquid amount; when the pulse signal is greater than or equal to the minimum pulse signal, and the pulse signal is less than the saturation pulse signal, the logarithmic amplification circuit is used for high gain processing or low gain processing of the pulse signal according to the pulse signal and the target gain parameter; the filter circuit is used for rectification processing of the pulse signal after high gain processing or low gain processing to obtain an analog signal; the conversion circuit is used for conversion processing of the analog signal to obtain discrete data; the processor is used for summing the first data to the Nth data of the discrete data to obtain a first sum value, and outputting a trigger signal when the first sum value is greater than or equal to a preset threshold value, the trigger signal is used for controlling the liquid suction needle to stop moving. The above device can effectively filter out the interference noise signal, and there is no misjudgment, which improves the detection accuracy.

A method for acquiring magnetic resonance (MR) data from a subject with a magnetic resonance imaging (MRI) system includes generating a first pre-saturation RF pulse having a first flip angle for each of at least one slice in the subject, generating a series of first gradient echo sequences following each first pre-saturation RF pulse, and calculating a B0 value for each of the at least one slice. A second pre-saturation RF pulse having a second flip angle is generated for each of the at least one slice in the subject, followed by a series of second gradient echo sequences, and a B1 is calculated for each of the at least one slice based on the first gradient echo sequences and the second gradient echo sequences.

The invention provides a magnetic resonance imaging method and magnetic resonance imaging equipment, and the method comprises the steps: for each to-be-generated magnetic resonance image in a magnetic resonance image sequence, in a preset time period corresponding to the magnetic resonance image and in an imaging region of at least a target object, carrying out the magnetic resonance imaging on the target object; sequentially generating a layer selection saturation pulse signal and N reversal pulse signals, wherein the N reversal pulse signals are used for performing first reversal operation on tissue in at least the imaging area; after or at the same time as performing the first inversion operation on the tissue in at least the imaging region by using the reciprocal (i + 1) th inversion pulse signal, and before performing the first inversion operation on the tissue in at least the imaging region by using the reciprocal ith inversion pulse signal, performing a second inversion operation on the blood in the marked region; magnetic resonance signals of tissue in the imaging region are acquired and a magnetic resonance image is generated. According to the scheme, the total consumed time of the magnetic resonance imaging process is shorter, and the imaging efficiency is remarkably improved.

The application relates to the technical field of medical equipment, in particular to a free-breathing abdominal chemical exchange saturation transfer imaging method and system, wherein the method comprises the following steps: collecting a respiratory motion signal of an imaging object; if a preset specific position of the respiratory motion signal is detected, triggering a water signal suppression sequence application module after a delay target time length, so that a water signal starts longitudinal relaxation recovery from 0; applying a CEST saturation pulse for a second preset time length after a delay first preset time length, and performing MR signal reading on the imaging object after the CEST saturation pulse application is completed, to obtain an MR image of the imaging object. Therefore, the problems that related technologies cannot overcome the influence of respiratory motion on abdominal CEST, have low implementation, poor usability, low accuracy and the like are solved.