14 results about "High field mri" patented technology

The invention provides a construction method of an ultrahigh-field MRI local shim coil based on topological optimization, and relates to the field of magnetic resonance imaging. The construction method provided by the invention comprises the following steps: step 1) selecting a target area needing to be subjected to magnetic field compensation, and obtaining a target magnetic field required by compensation of the target area; 2) representing current distribution by adopting a flow function, and obtaining magnetic field distribution generated by the current distribution; 3) taking the target magnetic field as a target, continuously iteratively optimizing the magnetic field distribution to approach the target magnetic field, and obtaining optimized current magnetic field distribution; and 4) winding a coil on a current-carrying surface by taking a current function corresponding to the optimized current magnetic field distribution as a reference. On the basis of a target field point method, a preset magnetic field compensation target is taken as a starting point, continuity and physical consistency of current distribution are ensured through flow function constraint, and regional specificity shimming compensation is realized by adopting a multi-current-carrying-surface topological optimization strategy.

The invention relates to the technical field of ultra-low field magnetic resonance systems, in particular to a battery charge state detection method and system based on closed-loop adaptive ultra-low field MRI, and the method comprises the steps: collecting the phase change of a water molecule H signal caused by the magnetic field disturbance of a to-be-detected battery, and reconstructing a first signal phase image; extracting to obtain a high-information-content area mask, and then performing resampling to obtain a second signal phase image; and inputting the second signal phase image into a state-of-charge detection model to predict a state-of-charge value of the to-be-detected battery. In order to solve the problem that a battery magnetic resonance detection scheme in the prior art needs to adopt a high-field magnetic resonance system and is not beneficial to production line use, detection equipment is replaced with an ultralow-field magnetic resonance system, so that structures such as a shielding room in a traditional magnetic resonance system are omitted, and a high-information-content area is positioned firstly, so that the detection efficiency is improved; and resampling is carried out on the region, so that the imaging precision is improved, and the accuracy of state of charge estimation of the detection model is improved.

The application discloses a 7T magnetic resonance head and neck tumor radiotherapy response evaluation system, belongs to the field of medical imaging and tumor radiotherapy, and comprises an ultrahigh-field multi-modal image acquisition module, a multi-phase accurate registration and radiomics feature extraction module, an early response biomarker identification module and an adaptive treatment decision support module. The high resolution, high signal-to-noise ratio and multi-nuclide imaging capability of the 7T ultrahigh-field magnetic resonance are utilized to acquire multi-modal images before and during treatment, more than 200 features are extracted through accurate registration and radiomics analysis, the treatment response is predicted based on the Delta feature and the deep learning model 2 to 3 weeks after the start of radiotherapy, the prediction accuracy reaches 87.5%, the prediction is 3 to 4 weeks earlier than the conventional evaluation, decision support is provided for timely adjustment of the treatment strategy, a closed-loop feedback mechanism is established, the clinical verification results are used to optimize the parameters of each module reversely, and continuous improvement is realized.

The invention relates to a transmitting coil. The transmitting coil comprises two end rings and a plurality of coil crosspieces, wherein the plurality of coil crosspieces are arranged between the two end rings; the structure of each coil crosspiece comprises a first dielectric layer, a plurality of first metal layers and a plurality of second metal layers, the plurality of first metal layers are distributed and attached to one side of the first dielectric layer, and the plurality of second metal layers are distributed and attached to the other side of the first dielectric layer; and each first metal layer and the second metal layer at the corresponding position of the other side of the first dielectric layer form a capacitor. By using the transmitting coil provided by the invention, the specific absorption rate (SAR) in high-field magnetic resonance scanning can be reduced.

The invention relates to a flexible leaky-wave antenna for uniform and efficient radio frequency transmission in ultrahigh field MRI, which comprises a double-layer dielectric substrate, a transmission line, an isolation pad and an LWA structure layer, the double-layer dielectric substrate comprises a first dielectric substrate and a second dielectric substrate, the transmission line comprises a first copper layer, the first copper layer is laid on the upper surface of the first dielectric substrate, and the isolation pad is laid on the upper surface of the second dielectric substrate. An isolation pad is arranged between the first dielectric substrate and the second dielectric substrate to form spaced arrangement of the double-layer dielectric substrates, the LWA structure layer comprises a second copper layer, six annular grooves with the same size are formed in the LWA structure layer at equal intervals, discs are embedded in the six annular grooves, and the LWA structure layer is arranged below the isolation pad and attached to the second dielectric substrate. And a flexible layer made of a segmented high-dielectric flexible material is arranged below the second dielectric substrate. The invention further comprises an antenna design method. According to the invention, the transmission efficiency of the LWA and the distribution uniformity of the B1 + field are improved, the flexible design fits the human body, and the signal intensity is improved.

The application discloses a traveling wave antenna unit, an array and a method for improving high-field magnetic resonance radio frequency field uniformity, relates to the field of magnetic resonance imaging, and aims to improve high-field magnetic resonance radio frequency field uniformity. The application increases the component of the wave number of the traveling wave antenna unit in the traveling wave transmission line direction in the traveling wave antenna array through physical or chemical means to relieve the radial standing wave effect. The traveling wave antenna unit comprises a layer-by-layer designed metal microstrip, a first bearing substrate, a filling layer substrate, a slotted metal floor, a second bearing substrate and a spacing layer substrate. A feeding port is connected between the first end of the metal microstrip and the slotted metal floor, and a load is connected between the second end of the metal microstrip and the slotted metal floor. The filling layer substrate is a fillable structure. The component in the traveling wave transmission line direction is increased by increasing the relative dielectric constant of the filling medium or changing the slotted structure. The application is simple in design, convenient in operation and does not need additional hardware.

The application discloses a method for high-resolution functional imaging in a high-field magnetic resonance system. The method comprises the following steps: S1, determining a two-dimensional spatially selective radio frequency pulse sequence applied to a brain of a subject organism, the two-dimensional spatially selective radio frequency pulse sequence is used for reducing a field of view (FOV) in a phase encoding direction and not generating signal folding. Preferably, the method further comprises the following step: S2, performing under-sampling and reconstruction on K-space based on an EPI-based GRAPPA algorithm. The application has the beneficial effect of realizing high-resolution functional imaging in a high-field magnetic resonance system.

The invention discloses a gadolinium-based magnetic resonance / near-infrared fluorescence bimodal probe as well as preparation and application thereof, and relates to the field of nano materials and medical engineering. The bimodal probe comprises nanoparticles formed by coordination and self-assembly of gadolinium ions and indocyanine green through sulfonic acid groups, and the molar ratio of the gadolinium ions to the indocyanine green is (2-10): 1. The bimodal probe shows the relaxation performance which is obviously superior to that of other clinical common contrast agents in a 9.4 T ultrahigh field magnetic resonance system, and the longitudinal relaxation rate of the bimodal probe can reach 22.3 mM <-1 > s <-1 >. The bimodal probe can be directly produced on a large scale on the basis of clinically approved drugs, and the bimodal probe has excellent imaging performance and blood-brain barrier penetrating power and provides a very potential strategy for image-guided biomedical application.

This invention provides a magnetic resonance receiving device suitable for auditory stimulation of awake marmosets, relating to the field of receiving coil design for magnetic resonance imaging. It includes an animal bed, a head fixation assembly, and a body shell. The animal bed has a placement slot; the head fixation assembly includes a mandibular support and a head shell, the mandibular support being detachably disposed in the placement slot, the head shell being detachably disposed above the mandibular support, and the body shell being detachably disposed on the animal bed; the head shell contains multiple radio frequency coils; both the mandibular support and the two side walls of the head shell have through slots for inserting auditory stimulation tubing. This invention, through the integrated design of radio frequency coils, a head fixation assembly, and an auditory stimulation-compatible interface, enables high-quality neuroimaging and precise simultaneous auditory stimulation experiments in an ultra-high field magnetic resonance environment.

The invention discloses a 7T magnetic resonance head and neck tumor radiotherapy response evaluation system, which belongs to the field of medical imaging and tumor radiotherapy and comprises an ultrahigh-field multi-modal image acquisition module, a multi-temporal precise registration and radiomics feature extraction module, an early response biomarker recognition module and a self-adaptive treatment decision support module. The high resolution, the high signal-to-noise ratio and the multi-nuclide imaging capability of 7T ultrahigh-field magnetic resonance are utilized, multi-modal images are collected before treatment and during treatment, more than 200 features are extracted through accurate registration and radiomics analysis, treatment response is predicted 2-3 weeks at the beginning of radiotherapy based on Delta features and a deep learning model, the prediction accuracy rate reaches 87.5%, and the prediction result is accurate. The method is 3-4 weeks earlier than conventional evaluation, decision support is provided for timely adjustment of treatment strategies, a closed-loop feedback mechanism is established for the system, parameters of all modules are reversely optimized according to clinical verification results, and continuous improvement is achieved.

The present application relates to the technical field of ultra-low field magnetic resonance system, and particularly relates to a battery state of charge detection method and system based on closed-loop adaptive ultra-low field MRI, comprising: collecting the phase change of water molecule H signal caused by the magnetic field disturbance of the battery to be detected to reconstruct a first signal phase image; extracting a high-information-area mask, then resampling to obtain a second signal phase image; inputting the second signal phase image into a state of charge detection model to predict the state of charge value of the battery to be detected. The battery magnetic resonance detection scheme in the prior art needs to use a high-field magnetic resonance system, which is not conducive to the use of the production line. The detection equipment is replaced with an ultra-low field magnetic resonance system, so that the shielding room and other structures in the traditional magnetic resonance system are omitted, and the imaging accuracy is improved by first locating the high-information-area and then resampling the area, thereby improving the accuracy of the detection model in estimating the state of charge.

The application discloses a magnetic resonance image enhancement method based on noise utilization and a generative adversarial network, and belongs to the technical field of medical image processing. The method comprises the following steps: acquiring paired 3T and 7T magnetic resonance images and preprocessing to obtain 3T MRI image blocks; a three-dimensional generative adversarial network with a fusion noise utilization mechanism is constructed, the generator is based on V-net construction and fuses a feature-level adaptive noise injection mechanism and a 3D CBAM attention module, and the discriminator is a four-stage hierarchical 3D convolutional network; a total loss function composed of pixel, perception, gradient structure consistency and adversarial loss is designed; the network is trained in an alternating update mode; and a 7T-level high-quality image is output by inputting a 3T image to be processed into the trained generator. The application effectively realizes high-quality enhancement from low-field to high-field magnetic resonance images, significantly improves the signal-to-noise ratio and resolution of the images, and is suitable for clinical auxiliary diagnosis.

According to the cerebral cortex multi-signal layer surface reconstruction method and system and the terminal provided by the invention, signal extraction is performed on the low-signal layer region presented in the image according to the brain region ultrahigh-field magnetic resonance image of the target object, and the initial low-signal layer inner surface and the initial low-signal layer outer surface obtained through extraction are subjected to surface reconstruction on the surface of the target object. Performing iterative optimization based on a preset multi-surface optimization energy function to obtain a target low-signal layer inner surface and a target low-signal layer outer surface; therefore, the multi-signal-layer surface of the cerebral cortex of the target object is reconstructed, and a basis is provided for quantitatively analyzing each signal layer and predicting the development degree and development trend of the cerebral cortex of the target object, whether a lesion occurs or not, the lesion type and the lesion degree and the like.