36 results about "Magnetocardiography" patented technology

The use of machine learning for pattern recognition in magnetocardiography (MCG) that measures magnetic fields emitted by the electrophysiological activity of the heart is disclosed herein. Direct kernel methods are used to separate abnormal MCG heart patterns from normal ones. For unsupervised learning, Direct Kernel based Self-Organizing Maps are introduced. For supervised learning Direct Kernel Partial Least Squares and (Direct) Kernel Ridge Regression are used. These results are then compared with classical Support Vector Machines and Kernel Partial Least Squares. The hyper-parameters for these methods are tuned on a validation subset of the training data before testing. Also investigated is the most effective pre-processing, using local, vertical, horizontal and two-dimensional (global) Mahanalobis scaling, wavelet transforms, and variable selection by filtering. The results, similar for all three methods, were encouraging, exceeding the quality of classification achieved by the trained experts. Thus, a device and associated method for classifying cardiography data is disclosed, comprising applying a kernel transform to sensed data acquired from sensors sensing electromagnetic heart activity, resulting in transformed data, prior to classifying the transformed data using machine learning.

This invention discloses methods and apparatuses for 3D imaging in Magnetoencephalography (MEG), Magnetocardiography (MCG), and electrical activity in any biological tissue such as neural/muscle tissue. This invention is based on Field Paradigm founded on the principle that the field intensity distribution in a 3D volume space uniquely determines the 3D density distribution of the field emission source and vice versa. Electrical neural/muscle activity in any biological tissue results in an electrical current pattern that produces a magnetic field. This magnetic field is measured in a 3D volume space that extends in all directions including substantially along the radial direction from the center of the object being imaged. Further, magnetic field intensity is measured at each point along three mutually perpendicular directions. This measured data captures all the available information and facilitates a computationally efficient closed-form solution to the 3D image reconstruction problem without the use of heuristic assumptions. This is unlike prior art where measurements are made only on a surface at a nearly constant radial distance from the center of the target object, and along a single direction. Therefore necessary, useful, and available data is ignored and not measured in prior art. Consequently, prior art does not provide a closed-form solution to the 3D image reconstruction problem and it uses heuristic assumptions. The methods and apparatuses of the present invention reconstruct a 3D image of the neural/muscle electrical current pattern in MEG, MCG, and related areas, by processing image data in either the original spatial domain or the Fourier domain.

In magnetocardiography, an assisting technique for a doctor diagnosing a heart disease will be provided. In the magnetocardiography, magnetism to be generated from a subject's heart is measured by a magnetic sensor, and from this measured data, a position of center of gravity of excitement wave front in a cardiac muscle excitement propagation process and a transition vector (wave front vector) is calculated by an analyzing computer. With this wave front vector as a feature parameter, the Mahalanobis' distance is calculated from a data base obtained by diagnosing in the past, a possibility (probability) of the subject having a heart disease is presumed on the basis of the Bayes' theorem for displaying. Also, by superimposing on a heart picture, the wave front vector position is displayed, and a cluster classification position in the wave front vector is displayed. Also, by the similar retrieval, another subject extremely similar to the subject in the feature parameter will be retrieved from the data base for screen displaying.

The invention provides a biological magnetic diagram instrument probe. The biological magnetic diagram instrument probe comprises a shell and a probe body, wherein the shell comprises a first containing part filled with first liquid inert gas; the probe body is arranged in the shell; the probe body comprises an air outlet, an electronic component, and a second containing part filled with second liquid inert gas; the first liquid inert gas is used for cooling the electronic component; the temperature of the second liquid inert gas is higher than the temperature of the first liquid inert gas and lower than the temperature of the air outlet; the second containing part is arranged in a conduction path through which first inert gas obtained after gasifying of the first liquid inert gas is conveyed to the air outlet from the first containing part. For the biological magnetic diagram instrument probe provided by the invention, a liquid nitrogen interlayer is arranged between liquid helium and the air outlet, so that helium gas evaporated by the liquid helium reaches the room temperature only after passing through the liquid nitrogen layer, therefore, the evaporation rate of liquid helium is greatly reduced, and the additional noise is avoided.

The invention provides a magnetocardiography, a compensation and optimization method based on the same, a system and a server. The compensation and optimization method comprises the following steps that second magnetic field signals produced by magnetometers on a super-conducing quantum interference device array layer are compensated by utilizing first magnetic field signals produced by compensation magnetometers on a compensation layer in a preset compensation mode to form third magnetic field signals after compensation; evaluation parameters of third magnetic field signals after compensation are calculated, the third magnetic field signals are evaluated according to comprehensive evaluations of evaluation parameters to optimize the compensation layer and determine the best compensation channel on the compensation layer. The residual magnetic field in a shielded room environment is effectively inhibited, so that 36 SQUID magnetocardiogram signals having high signal-to-noise ratio and high fidelity are output in a column mode.

The invention provides a magnetocardiography measurement system, which comprises: a detection component including a TMR magnetoresistive probe; a data acquisition and analysis unit connected with thedetection component and used for acquiring signals detected by the detection component and analyzing the detected signals; a magnetic field generation system used for generating a preset magnetic field value; a magnetic field shielding system connected with the magnetic field generation system so as to shield an external magnetic field through the magnetic field shielding system; and an auxiliarydetection equipment used for comparing the magnetocardiography measurement result provided by the invention. Through the technical scheme provided by the invention, the technical problem of high costof a magnetocardiography measurement system in the prior art can be solved.

The invention relates to a heart magnetic field simulation system based on a Helmholtz coil array. The system mainly comprises a magnetic shielding barrel (room), a low-noise program control current source and the Helmholtz coil array. The magnetic shielding barrel (room) is used for shielding an earth magnetic field and other external magnetic fields and providing working conditions for the heart magnetic field generated by measurement of the atom magnetometer, the low-noise program-controlled current source is used for generating current needed for simulating the heart magnetic field, and meanwhile the program-controlled current source has the advantage of facilitating simulation of a dynamic signal system. The Helmholtz coil array is used for generating a heart magnetic field in the normal direction of the thoracic cavity surface in magnetocardiography measurement. The system provided by the invention can generate the normal cardiac magnetic field of the thoracic cavity surface, is applied to research in the medical field, and facilitates simulation of the cardiac magnetic field of a patient and calibration of an atom magnetometer probe.

The invention relates to a three-dimensional imaging method based on a wearable magnetocardiography three-dimensional measuring device, and the wearable magnetocardiography three-dimensional measuring device obtains all three-dimensional magnetocardiography signals of a human body through a plurality of measuring sensors fixed by an adjustable vest in a magnetic shielding space. The method comprises the following steps: screening transmitted three-dimensional magnetocardiogram signals according to preset amplitude information, carrying out noise reduction and dimension reduction processing on the screened magnetocardiogram signals by adopting an independent component analysis and empirical mode decomposition method, and establishing a three-dimensional grid model comprising a trunk region, a heart region and a double-lung region based on a CT (Computed Tomography) image of a human body, a lead field matrix of magnetic field conduction from the heart to the position of the in-vitro sensor is obtained in a forward solving mode, and magnetic field distribution, used for real-time display, of the outer membrane surface of the heart is reversely solved based on the lead field matrix and the multi-channel signals. The wearable magnetocardiogram three-dimensional measuring device can synchronously obtain the three-dimensional magnetocardiogram signals, analyzes and displays the three-dimensional magnetocardiogram signals in real time, and is low in cost and convenient to carry.

The invention provides a magnetocardiogram generating method and system applied to a magnetocardiography. The magnetocardiogram generating method comprises the steps that firstly, the data in one cycle of each channel is intercepted, one point is selected from the intercepted data, the data of each channel at the point is get out, and then the position coordinates corresponding to the channels on the upper chest are calculated; secondly, the data of all the channels at the point correspond to the coordinates; thirdly, the two-dimensional magnetocardiogram data which are well arranged according to positions is subjected to two-dimensional interpolation; fourthly, the two-dimensional data obtained after interpolation is subjected to color table query; fifthly, a magnetocardiogram is drawn. The magnetocardiogram generated by using the method is clear in image and uniform in color distribution, and positive and negative dipoles can be clearly seen in the T wave band. Besides, if the magnetocardiograms from the S band to the T band of the QRS wave at different points are drawn according to a set step length, spatio-temporal evolution process of the heart activity current can be seen, and a doctor can diagnose whether a patient suffers from a heart disease or not according to the number of the dipoles of the magnetocardiogram and the evolution direction of the heart activity current.

A position adjustment apparatus for adjusting a position of a detection device, and a magnetocardiography instrument are provided. The position adjustment apparatus includes: two support assemblies, a lifting frame, and at least one height adjustment assembly. The position adjustment apparatus of the present disclosure enables free control over the height of the lifting frame by providing support rods and the height adjustment assembly comprising a pulley block.

The invention discloses a positioning method and system for the myocardial ischemia lesion position, a storage medium and a terminal. The positioning method comprises the following steps that a magnetocardiogram dataset collected by a multichannel magnetocardiography is pre-processed, and the averaged magnetocardiogram dataset of a T wave band is obtained; based on the magnetocardiogram dataset ofthe T wave band, the magnetic strength obtained by all channels of the multichannel magnetocardiography and the channel positions of all channels of the multichannel magnetocardiography, an iso-magnetic map and a current density map of the T wave band are obtained; based on the iso-magnetic map and the current density map, feature parameters related to the myocardial ischemia lesion position areextracted; and the myocardial ischemia lesion position is judged according to the feature parameters. According to the positioning method and system for the myocardial ischemia lesion position, the storage medium and the terminal, signal features of the magnetocardiogram are analyzed, the distribution rule of the feature parameters is excavated, and thus positioning of the myocardial ischemia lesion position is assisted according to the feature parameters sensitive to the myocardial ischemia position.

The invention discloses a device for calibrating a magnetic field-voltage coefficient of a multi-channel magnetocardiogram detection system. The device comprises a current excitation device which outputs a corresponding excitation current to a magnetic field generation mechanism based on a current control instruction, a magnetic field generating mechanism which generates a uniform magnetic field in a magnetometer area of the multi-through magnetograph, and a signal acquisition and analysis device which acquires voltage signals output by all the magnetometers, records voltage values of all the magnetometers under different magnetic field intensities, and fits voltage-magnetic field relation curves of all the magnetometers, wherein the fitting slope of the voltage-magnetic field relation curves is the voltage-magnetic field coefficient, and a magnetometer is excited by the uniform magnetic field to generate a voltage signal. The range of a uniform region of a magnetic field generated by the biplane coil and the uniformity of the magnetic field in the uniform region are larger than those of a common coil so that the accuracy of voltage-magnetic field coefficient calibration is improved; and an open space is formed between the double-plane coils so that the device is suitable for placing a magnetocardiography system with a complex structure and a relatively large volume, and the convenience of calibration operation is improved.

The invention provides a method, a system, a medium and a device for synchronizing multiple scanning data of a magnetocardiography, and the method comprises the steps: acquiring n times of magnetocardiogram data based on a plurality of detection channels, obtaining magnetocardiogram data from a first region to an nth region, and obtaining magnetocardiogram data of an (n+1)th region; respectively selecting the magnetocardiogram data of one detection channel included by the magnetocardiogram data of the (n+1)th region from the magnetocardiogram data of the first region to the nth region, and obtaining common point magnetocardiogram data of the first region to the nth region; identifying R peaks of the common dessert magnetic data from the first region to the nth region, and obtaining the R peaks of the common dessert magnetic data from the first region to the nth region; selecting any one of R peaks of the common point magnetic data of the first region and the nth region as a reference R peak, and calculating the time relation between other R peaks and the reference R peak; performing translation based on the moment relation, and obtaining synchronous multi-channel magnetocardiogram data. The method is used for obtaining the synchronous multi-channel magnetocardiogram data based on the single magnetocardiogram instrument.

The invention provides an auxiliary positioning method, system and equipment for a current source of magnetocardiography. The auxiliary positioning method for the current source of magnetocardiography comprises steps as follows: multiple magnetic dipoles fixedly adsorbed on the thoracic cavity of a human body are driven by alternating current at different frequencies to generate space magnetic fields at different frequency points; space magnetic field signals of the thoracic cavity of the human body are detected; intensity information of the space magnetic fields at different frequency points is acquired; the intensity information of the space magnetic fields at different frequency points is subjected to second preset treatment, so that a space position corresponding to the largest magnetic field value in the space magnetic field at each frequency point is acquired; magnetocardiography signals of the human body are subjected to third preset treatment, and the space position corresponding to the maximum current intensity of the magnetocardiography signals is acquired; the space position corresponding to the largest magnetic field value and the space position corresponding to the maximum current intensity are combined for auxiliary positioning. Positioning information can be acquired through measurement, mark points vary from person to person and are free from influence of the figure structure of the human body, and the auxiliary positioning method, system and equipment have wide clinical applicability.