35results about How to "Suppresses Motion Artifacts" patented technology

The invention relates to a method and a device for eliminating motion artifact of K spacial sampled data in a magnetic resonance imaging (MRI) system. The method comprises the following steps of: sampling data; preprocessing the data, namely ensuring the consistency of echo signal intensity, and moving the echo maximum to the center; estimating rotary motion, namely searching echo reference pairs between a rotary data tape and a basis data tape by utilizing frequency domain similarity, calculating relative angle offset among the reference pairs, establishing a rotary motion equation set, and introducing a constraint condition to solve rotary motion parameters; estimating translational motion, namely establishing a translational equation set to solve translational motion parameters according to a data consistency principle equivalent equation and the rotation angle obtained in the last step; compensating motion parameters, namely performing motion compensation on the motion parameters solved in the step 3 and the step 4; and performing filtered backprojection weighted reestablishment, namely adopting a filtered backprojection method for weighted reestablishment. The method or the device can effectively inhibit motion artifact.

The invention relates to a method for measuring three-dimensional morphological parameters of a blood vessel in an intracoronary ultrasound (ICUS) image sequence, which is used for improving the measurement accuracy of the morphological parameters of the blood vessel of a coronary artery. The technical scheme comprises the following steps of: completing three-dimensional reconstruction of the blood vessel by using the ICUS image sequence which is obtained by continuously withdrawing an ultrasound catheter and covers a plurality of cardiac cycles and cross information between two approximately vertical X-ray coronary arteriography images which are acquired at a starting point of a withdrawing path of the ultrasound catheter; and measuring and calculating the morphological parameters of the blood vessel which are important to clinical medicine by a geometric method by using a three-dimensional blood vessel model. Experiments prove that the measurement result of the morphological parameters of the blood vessel by the method is more accurate than that of the prior art, so that a reliable basis for visual diagnosis and treatment of coronary heart diseases and evaluation of interventional therapy effect is provided.

The invention discloses a steady-state procession gradient multi-echo water and grease separation imaging method. The steady-state procession gradient multi-echo water and grease separation imaging method comprises the following steps of on the basis of a steady-state procession imaging sequence for conventional scanning on a magnetic resonance imaging system, repeatedly exciting the imaging area by a radio frequency pulse at the interval of 10ms magnitude or smaller short cycle TR; setting a pulse flip angle into +alpha / 2 in a first sequence repetition cycle, and eliminating the sampling period; alternatively setting the pulse flip angle into +alpha and -alpha in the subsequent sequence repetition cycle; using the layer selection gradient, phase encoding gradient and frequency encoding gradient to perform three-dimensional encoding, wherein the sum of integral areas of gradients in each bearing is zero, and the proton magnetizing vector procession is approximate to the steady state; enabling the magnetizing vectors to form three or two gradient echoes under the action of three or two positive and negative alternating frequency encoding gradients in each TR period, wherein the integral area of gradients in the frequency encoding direction is zero; performing direct phase encoding on the three or two echoes according to echo peak interval and water and grease chemical displacement difference value.

In diffusion weighted imaging, motion monitoring navigation echoes are measured at every measurement of data after applying an RF excitation pulse, and one of them is set as a reference navigation echo. The reference navigation echo and other navigation echoes are one-dimensionally Fourier-transformed, a linear phase gradient thereof is calculated from those data, a linear phase gradient of the reference navigation echo is compared with those of other navigation echoes, and it is judged whether a difference therebetween is within an acceptable value or not. An echo signal corresponding to a navigation echo having the above difference being larger than the acceptable value is judged that correction based on the navigated motion correction is not applicable therein, and the image is produced by using an echo signal measured along with a navigation echo having the difference being the acceptable value or less. In this manner, a motion component included in the echo signal used for producing the image is made uniform and motion artifacts are eliminated.

The invention relates to a flexible dry type electrode for collecting electroencephalograms and a preparation method thereof. The flexible dry type electrode comprises an electrode body and an electric connecting piece, wherein the electrode body comprises an electrode bottom and array-structure probes arranged on the electrode bottom. The electric connecting piece is arranged at the electrode bottom, and the electric connecting piece and the array-structure probes are located on the two opposite surfaces of the electrode bottom correspondingly. The array-structure probes comprise a plurality of probe bodies annularly arranged along the electrode bottom, and the tail ends of the probe bodies in a probe array formed after the multiple probe bodies are arranged form a sunken three-dimensional arc-shaped curved surface. The flexible dry type electrode has the advantages that conductive adhesive / conductive paste is not needed, operation is easy and convenient, impedance is low, long-term stability, long-term reliability and flexibility are achieved, wearing of the flexible dry type electrode is comfortable and safe, the cost is low, and the machining technology is simple.

The invention provides a flexible graphene electroencephalogram capacitive electrode capable of inhibiting motion artifacts. The electrode comprises a substrate player, a fabric conductive layer, a first motion artifact inhibition layer, a filler layer, a second motion artifact inhibition layer, a touch surface layer and an insulated shielding layer, wherein flexible fabric forms the substrate layer; conductive cloth forms the fabric conductive layer; conductive sponge and conductive fabric form the first motion artifact inhibition layer; an insulated rubber plate forms the filler layer; the conductive cloth and the conductive sponge form the second motion artifact inhibition layer; a graphene coating forms the touch surface layer; insulated fabric forms the insulated shielding layer. The electrode is an electroencephalogram dry electrode according with a capacity coupling principle, a flexible electrode material is adopted, accordingly, no irritation and harm are caused to skin, and the electrode can be worn for a long time.

The invention provides a graphene flexible electrocardio dry electrode with an effect of inhibiting motion artifact. The electrode comprises a substrate layer, a fabric conductive layer, a motion artifact inhibiting layer, a contact surface layer and an insulation shielding layer, wherein the substrate layer is made of a flexible fabric; the fabric conductive layer is made of a conductive fabric; the motion artifact inhibiting layer is formed by a first buffer layer, a reinforcing layer and a second buffer layer; the first buffer layer and the second buffer layer are respectively made of conductive sponge; the reinforcing layer is made of the conductive fabric; the contact surface layer is formed by a graphene coating; and the insulation shielding layer is made of a center-hollow insulation fabric. The dry electrode can be used for overcoming irritation and damage of a traditional wet electrode on skin, is not a disposable electrode, and can be worn for a long time.

In order to prevent the occurrence of motion artifacts and improve image quality, the first displacement N1 of the diaphragm before the scanning part (2) has performed the imaging sequence and the second displacement N2 of the diaphragm after the scanning part (2) has performed the imaging sequence are detected by the body motion detection part (25) Detection is performed as displacement caused by breathing motion of the subject (SU). Thereafter, based on the first displacement N1 and the second displacement N2 detected by the body motion detection section (25), imaging data is selected as raw data by a raw data selection section (26). Then, according to the imaging data selected as raw data by the raw data selection part (26), the slice image of the subject (SU) is generated by the image generation part (31).

The invention relates to a bioelectrical signal flexible dry electrode and a preparing method thereof. The electrode is suitable for conduction of electroencephalogram signals of a non-hair or less-hair area (forehead area), muscle electrical signals and electrocardiogram signals and the like. The dry electrode is composed of two parts, namely the conductive flexible dry electrode body and an electrical connector. The conductive flexible dry electrode body is made of a flexible composite conductive material and has flexibility and good electrical conductivity; the surface is a three-dimensional arc-shaped curved surface and can make sufficient contact with skin and can restrain motion artifacts. The electrical connector is integrally poured in the electrode through the integrally forming process, the process complexity is reduced, and the contact impedance of the electrical connector and the electrode body is reduced. The bioelectrical signal flexible dry electrode has the advantages of being free of conductive glue / paste, easy and convenient to operate, low in impedance, stable, reliable and flexible in long term, comfortable and safe to wear, low in cost and simple in machining process.

In a non-Cartesian sampling method, a trajectory along which a measurement space is sampled is optimized. That is, data placed on one spiral trajectory heading outward from the center of the measurement space is sampled from a plurality of echo signals. The sampling is performed such that the data is placed continuously, without overlapping, in order from the center to the outside. Alternatively, the data may be overlapped and a mismatch between echo signals may be corrected using the data of the overlapped portion.

The invention provides a magnetic resonance scanning trigger method and device. The method includes the steps that a respiration curve of a subject is acquired, wherein the respiration curve comprisesmultiple respiration sub-curves, and each respiration sub-curve corresponds to one respiration period; based on the respiration sub-curves, respiration gating parameters in magnetic resonance sequences for controlling scanning are determined, wherein the respiration gating parameters comprise image acquisition time and acquisition delay time; based on the magnetic resonance sequences comprising the respiration gating parameters, the subject is controlled to be scanned. By means of the technical scheme, motion artifacts caused by respiration motion of the subject can be effectively restrained,and high-quality magnetic resonance images are obtained.

The invention discloses an electrocardiogram monitoring chest belt with a motion artifact inhibition function. The chest belt takes a flexible high-elasticity fabric as a base layer, two flexible fabric electrocardiograph dry electrodes, two pairs of auxiliary dry electrodes and a reference electrode are fixed on the base layer, the two flexible fabric electrocardiograph dry electrodes are horizontally distributed in the middle of the base layer, each pair of dry electrodes include upper auxiliary dry electrodes and lower auxiliary dry electrodes, the upper auxiliary dry electrodes and the lower auxiliary dry electrodes are symmetrically distributed on the upper side and the lower side of each flexible fabric electrocardiograph dry electrode, the two upper auxiliary dry electrodes are connected by the aid of a fiber resistor, the reference electrode is positioned at horizontal center between the two flexible fabric electrocardiograph dry electrodes, signal lines of each electrode penetrate the base layer and are connected with a signal processing module fixed on the other side of the base layer, the signal processing module is used for receiving signals of the electrodes and processing the signals to obtain electrocardiogram signals, and special woven seamless pressure adhesive is hollowed according to the shapes of the electrodes and adhered with the base layer to serve as aninsulation shielding layer. By the aid of the chest belt, motion artifacts can be effectively inhibited.

The invention relates to an ultrasonic doppler blood flow imaging method and system. The imaging method comprises the steps of obtaining a blood flow speed measuring interest region and the quantity of launching sub-hole diameters; according to the quantity of the launching sub-hole diameters, determining the inclination angle of a plane wave in each launching sub-hole diameter; according to the inclination angle, determining array element excitation delay time in each launching sub-hole diameter; according to the array element excitation delay time, controlling all the launching sub-hole diameters to synchronously emit plane waves, and receiving echo signals through a full hole diameter; generating a radio frequency signal sequence according to the echo signals; extracting blood flow doppler signals of the blood flow speed measuring interest region according to the radio frequency signal sequence; determining blood flow speed according to the blood flow doppler signals; and generatingdoppler blood flow images of the blood flow speed measuring interest region according to the blood flow speed. Through the adoption of the imaging method and system provided by the invention, the largest pulse repeating frequency can be realized, and besides, motion artifacts introduced by radio frequency signal compositing in ultra-high ultrasonic doppler blood flow imaging can be restrained.

The invention provides a pixel exposure method, and the method comprises the following steps: S1, performing first frame exposure on all pixels of an image sensor by adopting a global shutter exposuremode, and transferring first exposure charges generated after exposure of each pixel from a photodiode to a storage diode; S2, resetting the photodiode, performing second frame exposure on all pixelsof the image sensor by adopting the global shutter exposure mode again, and transferring a second exposure charge generated after each pixel is exposed to a storage diode from the photodiode; S3, transferring all the first exposure charges and all the second exposure charges to the floating diffusion node from the storage diode in sequence and reading out the charges line by line. According to the invention, by changing the control time sequence of the pixels, the motion artifact of the image can be effectively inhibited when the object moving at a high speed is shot on the premise of not losing the time resolution and the space resolution.

In a method for performing recordings for dual absorptiometry, a high-energy radiation pulse is performed before a low-energy radiation pulse. Furthermore the high-energy radiation pulse is arranged at the end of an assigned radiation window of the detector. This temporal sequence of a high-energy radiation pulse and a low-energy radiation pulse allows the total time for performing the recordings for dual absorptiometry to be minimized.

The embodiment of the invention provides an inhibition method for a motion artifact in colored blood flow imaging and equipment. The method comprises the steps that the blood flow speed and a corresponding grayscale image in colored blood flow imaging are acquired, the blood flow speed, smaller than a flow speed threshold value, of the blood flow speed is removed, the blood flow speed after processing is obtained, and at the same position of colored blood flow imaging, if the blood flow speed of multiple frames of images before the moment of colored blood flow imaging is zero, or the blood flow speed of only frame of image is not zero, and / or a grayscale value of the corresponding grayscale image is larger than or equal to a grayscale histogram mean value, the blood flow speed after processing is determined as the motion artifact; the motion artifact is removed, and the true blood flow speed is obtained. The inhibition method for the motion artifact in colored blood flow imaging and the equipment can have the advantage that the motion artifact in colored blood flow imaging can be inhibited.

An active noise cancellation device (2) for a medical device includes an active circuit having a first input connection (8), a second input connection (10), and an output connection (12). The second input connection (10) is connected to at least one predetermined reference signal. The active noise cancellation device (2) further includes a low-impedance body connection electrode (4) adapted to be in electrical contact with a bloodstream of a subject, wherein the low-impedance body connection electrode (4) is connected to said first input connection (8), and a feedback branch (14) connecting the output connection (12) with the first input connection (8). The feedback branch (14) comprises a current limiting circuit (18) to limit a current through said feedback branch (14) to be lower than a predetermined current.

The invention relates to a flexible dry type electrode for collecting electroencephalograms and a preparation method thereof. The flexible dry type electrode comprises an electrode body and an electric connecting piece, wherein the electrode body comprises an electrode bottom and array-structure probes arranged on the electrode bottom. The electric connecting piece is arranged at the electrode bottom, and the electric connecting piece and the array-structure probes are located on the two opposite surfaces of the electrode bottom correspondingly. The array-structure probes comprise a plurality of probe bodies annularly arranged along the electrode bottom, and the tail ends of the probe bodies in a probe array formed after the multiple probe bodies are arranged form a sunken three-dimensional arc-shaped curved surface. The flexible dry type electrode has the advantages that conductive adhesive / conductive paste is not needed, operation is easy and convenient, impedance is low, long-term stability, long-term reliability and flexibility are achieved, wearing of the flexible dry type electrode is comfortable and safe, the cost is low, and the machining technology is simple.

The invention is a graphene flexible electrocardiogram dry electrode for suppressing motion artifacts, which is composed of a base layer, a fabric conductive layer, a motion artifact suppressing layer, a contact surface layer and an insulating shielding layer, wherein the flexible fabric constitutes the base layer The conductive cloth constitutes the conductive layer of the fabric; the first buffer layer, the reinforcing layer and the second buffer layer constitute the motion artifact suppression layer, the conductive sponge constitutes the first buffer layer and the second buffer layer, and the conductive cloth constitutes the The strengthening layer; the graphene coating constitutes the contact layer; the central hollow insulating fabric constitutes the insulating shielding layer. The invention is a dry electrode, which overcomes the irritation and damage to the skin caused by the traditional wet electrode, is non-disposable, and can be worn and used for a long time.

The invention discloses a magnetic-resonance carotid plaque radiofrequency imaging coil, which is characterized by comprising a left coil shell body, a right coil shell body, a wiring box, a clamping frame and a cable, wherein a coil unit is arranged in each of the left coil shell body and the right coil shell body, each coil unit comprises a matrix loop formed by matching four groups of low-noise amplifying circuits, protective circuits, tuning circuits and decoupling circuits, and the shape of each coil unit and the corresponding matched circuits are different from one another through optimization, so as to adapt to irregular shapes of necks of human bodies. According to the magnetic-resonance carotid plaque radiofrequency imaging coil, the structures of the coil units adopt an optimal design, the magnetic-resonance carotid plaque radiofrequency imaging coil can be closely adhered to a detected portion when in use, the signal transmission efficiency is effectively improved, the signal attenuation is reduced, and the beneficial effects of high definition and high resolution are achieved.

An ultrasonic Doppler blood flow imaging method and system are provided. The method includes: acquiring a blood flow velocity measuring interest region and a number of transmitting sub-apertures; determining, according to the number of transmitting sub-apertures, inclination angle of a plane wave in each of the transmitting sub-aperture; determining, according to inclination angle, array element excitation delay time in each of the transmitting sub-aperture; controlling, according to array element excitation delay time, all of transmitting sub-apertures to synchronously transmit plane waves, and receiving echo signals with a full aperture; generating a radio frequency signal sequence according to echo signals; extracting blood flow Doppler signals of blood flow velocity measuring interest region according to radio frequency signal sequence; determining a blood flow velocity according to blood flow Doppler signals; and generating a Doppler blood flow image of blood flow velocity measuring interest region according to blood flow velocity.

Embodiments of the present invention provide a method and device for suppressing motion artifacts in color blood flow imaging. Wherein, the method includes: acquiring the blood flow velocity and the corresponding grayscale image in the color blood flow imaging, removing the blood flow velocity smaller than the flow velocity threshold value in the blood flow velocity, and obtaining the processed blood flow velocity, in the In the same position of color blood flow imaging, if the blood flow velocity of several frames of images before the moment of color blood flow imaging is zero, or the blood flow velocity of only one frame of image is not zero, and / or the corresponding grayscale If the gray value of the image is greater than or equal to the mean value of the gray histogram, it is determined that the processed blood flow velocity is a motion artifact; the motion artifact is removed to obtain a real blood flow velocity. The method and device for suppressing motion artifacts in color blood flow imaging provided by the embodiments of the present invention can achieve the technical effect of suppressing motion artifacts in color blood flow imaging.

The present invention relates to an adaptive correction method for magnetic resonance diffusion weighted imaging, comprising the following steps: step 1, repeating acquisition of diffusion weighted images N times with the same scanning parameters, N≥3; step 2, based on the original image or compressed image point by point Construct a correlation matrix; step 3, perform principal component analysis on the correlation matrix after smoothing and filtering, and obtain the eigenvector corresponding to the largest eigenvalue of each correlation matrix; step 4, calculate the weight according to the eigenvector; step 5, according to Weighting performs weighted synthesis on the original image to obtain a corrected diffusion-weighted image. On the basis of multiple acquisition average technology, the present invention adopts principal component analysis method to adaptively detect and correct data from redundant data, suppress motion artifacts, radio frequency ignition artifacts, etc., and improve image quality; no need to increase Hardware device, and the image quality is better than multiple acquisition direct averaging technology.

The invention discloses a capacitor electrode for detecting electrocardiogram signals of a motorist. The capacitor electrode for detecting the electrocardiogram signals of the motorist comprises a supporting component, a signal detecting component and a buffer component, wherein the supporting component is composed of a metal plate; the signal detecting component is composed of a double-sided PCB (printed circuit board) with a voltage snubber circuit, the voltage snubber circuit is arranged on the bottom surface of the PCB and comprises CMOS (Complementary Metal-Oxide-Semiconductor Transistor) type double precision operational amplifiers with high input impedance and low noise; and the buffer component is composed of springs and is used for connecting the supporting component and the signal detecting component. The capacitor electrode for detecting the electrocardiogram signals of the motorist utilizes the double-sided PCB as the signal detecting component so that the structure is simple and the cost is low; utilizes springs as the buffer component so that the motion artifact caused by the body movement of a detected object during a signal detecting process is effectively restrained; and utilizes the mental plate as the supporting component so that not only a supporting function is achieved, but also an electromagnetic shielding function for the signal detecting component is achieved.

An active noise cancellation device (2) for medical equipment comprises an active circuit having a first input connection (8), a second input connection (10) and an output connection (12). The second input connection (10) is connected to at least one predetermined reference signal. The active noise canceling device (2) further comprises a low-impedance body-connected electrode (4) adapted to be in electrical contact with the subject's blood flow, wherein the low-impedance body-connected electrode (4) is connected to said first input connection (8), and a feedback branch (14) connects the output connection (12) with the first input connection (8). The feedback branch (14) includes a current limiting circuit (18) for limiting the current through said feedback branch (14) to below a predetermined current.

The invention relates to a method and a device for eliminating motion artifact of K spacial sampled data in a magnetic resonance imaging (MRI) system. The method comprises the following steps of: sampling data; preprocessing the data, namely ensuring the consistency of echo signal intensity, and moving the echo maximum to the center; estimating rotary motion, namely searching echo reference pairsbetween a rotary data tape and a basis data tape by utilizing frequency domain similarity, calculating relative angle offset among the reference pairs, establishing a rotary motion equation set, and introducing a constraint condition to solve rotary motion parameters; estimating translational motion, namely establishing a translational equation set to solve translational motion parameters according to a data consistency principle equivalent equation and the rotation angle obtained in the last step; compensating motion parameters, namely performing motion compensation on the motion parameters solved in the step 3 and the step 4; and performing filtered backprojection weighted reestablishment, namely adopting a filtered backprojection method for weighted reestablishment. The method or the device can effectively inhibit motion artifact.

The invention relates to a motion artifact suppression method for wearable electrocardiogram monitoring equipment. Two same electrocardio-electrodes SN and RA are respectively placed in the same position on the chest, in particular the second rib corresponding to the centre line of the right clavicle, to be in contact with skin, wherein the output of the electrocardio-electrode RA is used as a reference signal; the difference between the output of the electrocardio-electrode SN and the reference signal is amplified by a certain multiple to serve as a motion noise signal; the difference betweenthe output signals of the rest placement electrodes and the reference signal is amplified by the same amplification multiple to be subtracted from the motion noise signal; and the difference value isa real electrocardiosignal after motion artifacts are eliminated. The invention further provides twelve-lead wearable electrocardiogram monitoring equipment based on the motion artifact suppression method; the twelve-lead wearable electrocardiogram monitoring equipment comprises an underwear body, an electrocardiogram sensor and an electronic processing unit; the electrocardiogram sensor comprises ten electrocardiogram probes; a standard medical twelve-lead electrocardiogram can be obtained through combination; motion artifacts can be effectively suppressed; and the quality of electrocardiosignals is improved.

The invention relates to a method for measuring three-dimensional morphological parameters of a blood vessel in an intracoronary ultrasound (ICUS) image sequence, which is used for improving the measurement accuracy of the morphological parameters of the blood vessel of a coronary artery. The technical scheme comprises the following steps of: completing three-dimensional reconstruction of the blood vessel by using the ICUS image sequence which is obtained by continuously withdrawing an ultrasound catheter and covers a plurality of cardiac cycles and cross information between two approximatelyvertical X-ray coronary arteriography images which are acquired at a starting point of a withdrawing path of the ultrasound catheter; and measuring and calculating the morphological parameters of theblood vessel which are important to clinical medicine by a geometric method by using a three-dimensional blood vessel model. Experiments prove that the measurement result of the morphological parameters of the blood vessel by the method is more accurate than that of the prior art, so that a reliable basis for visual diagnosis and treatment of coronary heart diseases and evaluation of interventional therapy effect is provided.

The present disclosure relates to systems and methods for reconstructing an Emission Computed Tomography (ECT) image. The systems, having at least one machine each of which has at least one processorand storage, may perform the methods to obtain ECT projection data, the ECT projection data corresponding to a plurality of voxels; determine a plurality of gate numbers for the plurality of voxels, the plurality of gate numbers relating to motion information of the plurality of voxels; and reconstruct an ECT image based on the ECT projection data and the plurality of gate numbers.