Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
  • A61B6/03—Computed tomography [CT]
  • A61B6/037—Emission tomography
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
  • A61B5/242—Detecting biomagnetic fields, e.g. magnetic fields produced by bioelectric currents
  • A61B5/243—Detecting biomagnetic fields, e.g. magnetic fields produced by bioelectric currents specially adapted for magnetocardiographic [MCG] signals
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
  • A61B5/316—Modalities, i.e. specific diagnostic methods
  • A61B5/318—Heart-related electrical modalities, e.g. electrocardiography [ECG]
  • A61B5/346—Analysis of electrocardiograms
  • A61B5/349—Detecting specific parameters of the electrocardiograph cycle
  • A61B5/352—Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
  • A61B6/03—Computed tomography [CT]
  • A61B6/032—Transmission computed tomography [CT]
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/50—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment specially adapted for specific body parts; specially adapted for specific clinical applications
  • A61B6/503—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment specially adapted for specific body parts; specially adapted for specific clinical applications for diagnosis of the heart
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
  • A61B6/5211—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data
  • A61B6/5229—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data combining image data of a patient, e.g. combining a functional image with an anatomical image
  • A61B6/5235—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data combining image data of a patient, e.g. combining a functional image with an anatomical image combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
  • A61B6/5211—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data
  • A61B6/5229—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data combining image data of a patient, e.g. combining a functional image with an anatomical image
  • A61B6/5247—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data combining image data of a patient, e.g. combining a functional image with an anatomical image combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/52—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/5215—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves involving processing of medical diagnostic data
  • A61B8/5238—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves involving processing of medical diagnostic data for combining image data of patient, e.g. merging several images from different acquisition modes into one image
• • G—PHYSICS
  • G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
  • G16H—HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
  • G16H50/00—ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics
  • G16H50/50—ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics for simulation or modelling of medical disorders
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/41—Detecting, measuring or recording for evaluating the immune or lymphatic systems
  • A61B5/413—Monitoring transplanted tissue or organ, e.g. for possible rejection reactions after a transplant
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/74—Details of notification to user or communication with user or patient; User input means
  • A61B5/742—Details of notification to user or communication with user or patient; User input means using visual displays
  • A61B5/743—Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots

Definitions

• the present invention relates to an apparatus for diagnosing a viable myocardium and a method for analyzing a viable myocardium by magnetic field measurement, and more particularly, to a damaged site or a viable myocardium that causes the formation of an oscillating loop (circular circuit) of an abnormal current in left and right ventricles
• the present invention relates to a viable myocardium diagnostic apparatus and a viable myocardial analysis method using magnetic field measurement for non-invasively identifying a site by noncontact magnetic measurement.
• electrocardiography has been generally employed to diagnose heart disease.
• conventional electrocardiography has been insufficient for estimating the position, size, and shape of a myocardial injury site or a viable myocardial site, for example, before cardiac surgery.
• ECG is an indirect measurement method.
• the tissue that exists from the heart to the body surface, the positional relationship between the heart and other organs and bones, the size of the heart, the electrical conductivity of each tissue of the human body, etc. vary greatly from subject to subject. It was extremely difficult to accurately determine the position of the affected part based on the information obtained in (1).
• surviving myocardium the site of physiologically living myocardium (hereinafter referred to as “surviving myocardium”) and the heart chamber are mixed, an abnormal electrical circuit is formed in the myocardium, and May cause beats. Therefore, there is a strong demand for accurately identifying such a myocardial lesion site or a viable myocardial site three-dimensionally.
• the electrocardiography can diagnose the presence or absence of a myocardial injury site due to ischemia, but recognizes the position, size, and shape of the myocardial injury site in the heart could not at all.
• MRI nuclear magnetic resonance
• X-ray CT X-ray CT
• a radioisotope such as a myocardial SPECT method or a PET method.
• Evaluation of myocardial tissue properties also requires invasive methods of direct tissue sampling, such as catheter-based or surgical sampling of myocardial tissue (myocardial biopsy).
• the above-mentioned examination methods such as myocardial SPECT or PET using radioisotopes are a method to accurately evaluate the survival state of myocardium before and after angina pectoris and coronary artery bypass surgery. It's being used.
• these inspection methods use radioisotopes and must be used in controlled areas, and are expensive.
• the rejected myocardium after heart transplantation, the rejected myocardium must be evaluated to determine whether treatment is needed depending on the degree of rejection, and the presence or absence of multiple rejections over time at relatively short intervals. Inspection needs to be performed.
• changes in myocardial rejection can be detected by electrocardiography or echocardiography, it has the accuracy necessary for diagnosis, that is, the accuracy necessary to estimate the degree of rejection. I haven't.
• a method of regularly performing myocardial biopsy using a catheter has been adopted, which places a heavy burden on patients. Therefore, there is a strong demand for a device capable of three-dimensionally diagnosing the position, size, and extent of rejected myocardium after heart transplantation using noninvasive measurement means.
• a SQUID magnetometer that uses a superconducting Quantum Interference Device (hereinafter abbreviated as SQUID) that can detect a magnetic flux of about one billionth of geomagnetism with high sensitivity.
• SQUID superconducting Quantum Interference Device
• the magnetocardiogram alone can be used to determine the site of myocardial damage or the viable myocardium in the human body.
• the position, size, shape, and degree of the site could not be displayed directly, making it difficult to accurately inform the doctor of the relative positional relationship of the affected area in the heart.
• an object of the present invention is to provide a safe, rapid and highly accurate three-dimensional analysis of a myocardial injury site or a viable myocardial site based on data showing the current density distribution in the myocardium obtained by non-invasive magnetic measurement. It is an object of the present invention to provide an apparatus for diagnosing viable myocardium and a method for analyzing viable myocardium by magnetic field measurement, which can be identified. Disclosure of the invention
• a surviving myocardium diagnostic device based on magnetic field measurement includes a magnetic field distribution measuring device, a first arithmetic device, a second arithmetic device, and a display device.
• the magnetic field distribution measuring device acquires a plurality of magnetic field time series data corresponding to a plurality of coordinates by non-contact magnetic measurement at a plurality of coordinates on the subject's chest, and obtains a plurality of magnetic field time series data based on the plurality of magnetic field time series data.
• the magnetic field distribution time series data is generated.
• the first arithmetic unit generates time series data of a current density distribution in the myocardium of the subject based on the generated magnetic field distribution time series data.
• the second processing device processes the separately supplied chest tomographic image data of the subject to generate data indicating an anatomical image.
• the display device superimposes the image of the current density distribution in the myocardium indicated by the data generated by the first arithmetic device on the keratological image indicated by the data generated by the second arithmetic device. Perform display processing to display. As a result, a myocardial lesion site or a surviving myocardium site showing an abnormal current density distribution can be identified three-dimensionally.
• the first arithmetic unit divides the left ventricle and the right ventricle into a plurality of arbitrary regions based on an anatomical factor or a functional factor and divides the current density in the myocardium for each region.
• anatomical factor or a functional factor divides the current density in the myocardium for each region.
• the surviving myocardial diagnosis device based on magnetic field measurement includes a database including information for determining a relationship between a current density in the myocardium indicated by data generated by the first arithmetic device and a myocardial injury current. Is further provided.
• a surviving myocardial diagnosis device using magnetic field measurement includes a magnetic field distribution measuring device, an arithmetic device, and a display device.
• the magnetic field distribution measurement device acquires a plurality of magnetic field time series data corresponding to a plurality of coordinates by non-contact magnetic measurement at a plurality of coordinates on the subject's chest, and obtains a magnetic field on the chest based on the plurality of magnetic field time series data.
• Generate field distribution time series data Generate field distribution time series data.
• the arithmetic unit generates time series data of the current density distribution in the myocardium of the subject based on the generated magnetic field distribution time series data.
• the display device based on the data generated by the arithmetic device, generates an image showing the stimulus propagation path from the sinoatrial node of the subject's heart to the His bundle and the Purkinje fiber system, and an image showing the current density distribution in the myocardium.
• a display process for superimposed display is performed. This makes it possible to three-dimensionally identify a myocardial lesion site or a viable myocardial site exhibiting an abnormal current density distribution.
• the arithmetic unit divides the left ventricle and the right ventricle into a plurality of arbitrary regions based on anatomical factors or functional factors, and generates time-series data of a current density distribution in the myocardium for each region.
• the myocardial injury site in the left ventricle and the right ventricle can be identified three-dimensionally.
• the apparatus for diagnosing a viable myocardium by magnetic field measurement further includes a database including information for judging a relationship between a current density in the myocardium indicated by data generated by the calculation means and a myocardial injury current.
• a method for analyzing a viable myocardium by magnetic field measurement is based on a plurality of magnetic field time-series data corresponding to a plurality of coordinates acquired by a non-contact magnetic measurement at a plurality of coordinates on a subject's chest.
• Generating first data which is time-series data of current density distribution in the myocardium of the subject, based on the generated time-series data of the magnetic field distribution on the chest; and separately supplied chest tomographic image of the subject.
• the step of generating the first data includes dividing the left ventricle and the right ventricle into an arbitrary plurality of regions based on an anatomical factor or a functional factor, and dividing the current density distribution in the myocardium for each region. Then, the time series data of the left ventricle and the right ventricle can be three-dimensionally identified.
• the surviving myocardial analysis method using magnetic field measurement is characterized in that the part three-dimensionally identified based on the information indicating the relationship between the current density in the myocardium indicated by the first data and the myocardial damage current is determined.
• the method further includes the step of determining whether the site is a site or a viable myocardial site.
• the method for analyzing a living myocardium by magnetic field measurement includes a method for analyzing a plurality of magnetic field time-series data corresponding to a plurality of coordinates obtained by a non-contact magnetic measurement at a plurality of coordinates on a subject's chest. Generating time-series data of current density distribution in the myocardium of the subject based on the time-series data of the magnetic field distribution on the chest generated based on the data; and sinoatrial node of the subject's heart based on the generated data.
• the myocardial lesion site By superimposing an image showing the stimulus propagation path from the His bundle to the Purkinje fiber system and an image showing the current density distribution in the myocardium, the myocardial lesion site showing an abnormal current density distribution, or Allowing the living myocardial site to be identified three-dimensionally.
• the step of generating data includes dividing the left ventricle and the right ventricle into a plurality of arbitrary regions based on anatomical factors or functional factors, and time-series the current density distribution in the myocardium for each region.
• the myocardial lesions in the left ventricle and right ventricle can be identified three-dimensionally.
• the viable myocardial analysis method using magnetic field measurement is characterized in that the three-dimensionally identified region is a myocardial lesion based on information indicating the relationship between the current density in the myocardium indicated by the data and the myocardial lesion current.
• the method further includes the step of determining whether the site is a living myocardium.
• the image showing the current density distribution in the myocardium obtained by non-invasive magnetic measurement can be used to obtain a chest tomographic image of the same subject taken by another medical diagnostic apparatus.
• doctors can safely, promptly, and accurately detect a portion of the myocardial disorder or a viable myocardium that exhibits an abnormal current density distribution. Dimensional identification becomes possible.
• an image showing the current density distribution in the myocardium obtained by non-invasive magnetic measurement is used as an image showing a stimulus propagation path from the sinoatrial node of the heart of the same subject to the His bundle and the Purkinje fiber system.
• FIG. 1 is a functional block diagram schematically showing a configuration of a viable myocardial diagnosis device based on magnetic field measurement according to Embodiment 1 of the present invention.
• FIG. 2 is a block diagram showing a more specific configuration of the surviving myocardium diagnostic apparatus based on magnetic field measurement shown in FIG.
• FIG. 3 is a block diagram showing a detailed configuration of the magnetic field distribution measuring device shown in FIG.
• FIG. 4 is a diagram showing an example of an arrangement of a plurality of magnetic field sensors on the front of the chest of the subject.
• FIG. 5 is a diagram showing magnetic field time-series data obtained from each of the plurality of sensors in FIG.
• FIG. 6 is a diagram schematically illustrating a method of calculating current density data from magnetic field time-series data.
• FIG. 7A and 7B are diagrams showing examples of a three-dimensional anatomical image displayed on the display device 4.
• FIG. 7A and 7B are diagrams showing examples of a three-dimensional anatomical image displayed on the display device 4.
• FIG. 8 is a tomogram showing one section of the three-dimensional anatomical image shown in FIGS. 7A and 7B.
• FIG. 9 is a flowchart illustrating the operation of the apparatus for diagnosing viable myocardium by magnetic field measurement according to the first embodiment of the present invention.
• FIG. 10 is a front view illustrating the operation of the surviving myocardial diagnosis device based on magnetic field measurement according to the modification of the first embodiment of the present invention.
• FIG. 11 is a diagram schematically showing one mode of dividing the ventricle into regions.
• FIG. 12 is a flowchart illustrating the operation of the surviving myocardial diagnostic device by magnetic field measurement according to a further modification of the first embodiment of the present invention.
• FIG. 13 is a functional block diagram schematically showing a configuration of a surviving myocardial diagnosis device using magnetic field measurement according to the second embodiment of the present invention.
• FIG. 14 is a more specific block diagram showing the configuration of the living-myocardial diagnosis apparatus based on magnetic field measurement according to the second embodiment of the present invention shown in FIG. 13.
• FIGS. 15A and 15B are diagrams schematically showing a normal stimulus propagation path and an electrocardiogram waveform in the heart.
• FIG. 16 is a diagram showing images of the normal stimulus propagation path and the abnormal current density distribution actually displayed by the display device 7.
• FIG. 17 is a flowchart illustrating the first half of the operation of the apparatus for diagnosing viable myocardium by magnetic field measurement according to the second embodiment.
• FIG. 18 is a flowchart illustrating the latter half of the operation of the surviving myocardium diagnostic apparatus using magnetic field measurement according to the second embodiment.
• FIG. 19 is a flowchart for explaining the latter half of the operation of the surviving myocardial diagnosis device based on magnetic field measurement according to the modification of the embodiment 2.
• FIG. 20 is a flowchart illustrating the latter half of the operation of the apparatus for diagnosing a viable myocardium by magnetic field measurement according to a further modification of the second embodiment.
• FIG. 1 is a functional block diagram schematically showing a configuration of a surviving myocardium diagnostic apparatus using magnetic field measurement according to Embodiment 1 of the present invention.
• the magnetic field distribution measurement device 1 performs non-contact magnetic measurement at a plurality of coordinates on a subject's chest using, for example, measurement means such as an S QU ID magnetometer described in detail below. Acquire a plurality of magnetic field time-series data corresponding to a plurality of coordinates. Then, based on the acquired plurality of magnetic field time series data, Generate and output magnetic field distribution time series data of the magnetic field.
• measurement means such as an S QU ID magnetometer described in detail below.
• the first arithmetic device 2 uses, for example, various known calculation methods described below to calculate the current in the myocardium. Generate and output first data, which is time series data of the density distribution.
• first data which is time series data of the density distribution.
• the second arithmetic unit 3 processes the tomographic image data to generate and output second data indicating a three-dimensional anatomical image. I do.
• the above-described first data is represented by an image.
• the density of the image representing the current density distribution it becomes possible to three-dimensionally identify a portion of a myocardial injury or a portion of a viable myocardium exhibiting an abnormal current density.
• the display device 4 displays an image showing the current density distribution in the myocardium indicated by the first data generated by the first arithmetic device, and an image of the subject indicated by the second data generated by the second arithmetic device 3.
• the 3D anatomical image of the chest is superimposed and displayed.
• a myocardial lesion site or a viable myocardium site in the myocardium can be three-dimensionally identified on the anatomical image.
• the display device 4 only displays the current density distribution itself in the myocardium. Therefore, a database 5 containing judgment information on the relationship between the current density distribution in the myocardium and the myocardial injury current is provided, and the current density distribution actually calculated by the first arithmetic unit 2 is compared with the judgment information in the database 5. By displaying the result on the display device 4, it is possible to more accurately determine whether the site of the current density is a damaged myocardium (for example, an ischemic myocardium site, a rejected myocardium, etc.) or a viable myocardium. It becomes possible.
• a damaged myocardium for example, an ischemic myocardium site, a rejected myocardium, etc.
• FIG. 2 is a block diagram showing a more specific configuration of the surviving myocardial diagnostic device based on magnetic field measurement according to the first embodiment of the present invention shown in FIG.
• a magnetic field distribution measuring device 1 is installed in a magnetic shield room (MSR) 11 so as to perform non-contact magnetic measurement on the chest of a subject 12.
• MSR magnetic shield room
• Duplex with built-in S QU ID magnetometer -13 and a magnetic field distribution data calculation unit 14 are provided.
• the Dewar 13 there is formed a low-temperature environment in which the liquid helm is filled and superconductivity is generated, and the SQUID magnetometer composed of a detection coil composed of a superconductor is accommodated therein.
• Fig. 3 is installed in the ultra low temperature system in the dewar 13 in the MSR 11 shown in Fig. 2.
• FIG. 4 is a block diagram showing the S QU ID magnetometer 15 and a calculation unit 14 installed in the MSR 11 of a normal temperature system in more detail.
• the configuration shown in FIG. 3 is a configuration for one channel for measuring magnetic field data at one point on the chest of the subject. As will be described later, in the present invention, a plurality of channels are provided on the chest of the subject. Simultaneous multipoint measurement of magnetic field at coordinates. Therefore, the configuration for one channel shown in FIG. 3 is provided in the MSR 11 of FIG. 2 for a plurality of channels required for measurement.
• the SQUID magnetometer 15 includes a pickup coil 16 made of a superconductor for detecting a magnetic field generated from the chest surface of the subject.
• a pickup coil 16 made of a superconductor for detecting a magnetic field generated from the chest surface of the subject.
• an electric current flows, and this current is drawn into the coil 17 to generate a magnetic field in the Nb sinorode 20.
• a magnetic field that changes linearly with respect to this magnetic field is formed in the superconducting loop 18, and the voltage at both ends of the superconducting loop 18 is calculated by the arithmetic unit 14 installed in the normal temperature MSR 11.
• the arithmetic unit 14 detects the current by the amplifier and adjusts the current flowing through the modulation coil 19 in the Nb shield 20 so that the detected voltage does not change.
• the detection of the magnetic field of a living body by SQUID does not directly measure the generated magnetic field, but uses the so-called zero-position method to apply feedback so that the magnetic field in the superconducting ring 18 is always constant ( More specifically, the current flowing through the modulation coil 19 is adjusted to control the magnetic field generated in the modulation coil 19 so that a constant magnetic field is always generated in the superconducting loop 18).
• the magnetic field detected by coil 16 is applied to arithmetic unit 14 It is converted into an air signal and output.
• Such a feedback method is usually a well-known technique called a flux locked loop (FLL).
• the configuration shown in Fig. 3 is necessary for measuring the magnetic field data for one channel, and the electrical signal indicating the magnetic field time-series data of the magnetic field measured at one point on the front of the subject's chest Is output.
• many sensors SQUID magnetometer
• the magnetic field on the front of the chest is measured at multiple points.
• the magnetic field changes with time. For example, even during a period corresponding to one heartbeat, if the measurement location is different, the magnetic field changes differently depending on the location.
• FIG. 4 is a diagram showing an example of the arrangement of a plurality of sensors (each of which is a single channel SQUID magnetometer) on the front of the chest of the subject.
• FIG. 5 shows a group of magnetic field time-series data showing a change in a magnetic field during one heartbeat period obtained from each sensor corresponding to each position of the plurality of sensors in FIG. I have.
• the data output from the magnetic field distribution measurement device 1 shown in FIG. 2 is a group of magnetic field time-series data corresponding to a plurality of measurement positions (coordinates) as shown in FIG. Focusing on a specific time, these one group of magnetic field time-series data is captured, and the actual peaks and valleys showing the distribution of the magnetic field strength at a certain time on the front of the chest to be measured are displayed in a graph. Since it is difficult to express in (Fig.), Magnetic field distribution data expressed in a contour map, such as the atmospheric pressure in a weather chart, can be obtained. In this sense, the data output from the magnetic field distribution measuring device 1 can be regarded as magnetic field distribution time-series data on the front of the chest.
• the group of magnetic field time-series data output from the magnetic field distribution measuring device 1, that is, the magnetic field distribution time-series data, is given to the first arithmetic device 2 in FIG. 2 functions to obtain the current density in the chest flowing at that moment based on the magnetic field distribution data at a certain time.
• the first computing device calculates the current density distribution flowing through a site in the human body (the heart in the present invention) to be measured. The method to be determined in Section 2 is described.
• FIG. 6 is a diagram schematically illustrating a method for obtaining such a current density.
• a current sensor virtual sensor
• the current output of the virtual sensor can be obtained by multiplying the coefficients by the coefficients in the magnetic field time series data obtained from all the sensors (SQUID magnetometers) installed on the front of the human chest and taking the sum. Can be. How to find this coefficient is the central issue in this calculation.
• the method of obtaining the current density will be described in more detail with reference to FIG.
• N magnetic field sensors are arranged on the human body surface (front of the chest).
• the human body (chest, especially the heart) to be analyzed is regarded as a set of voxels, each of which is a small block.
• the total number of the bottom cells is M.
• the poxels through which the distributed currents of the orthogonal components flow are arranged at the same coordinates.
• the component orthogonal to the plane shown in 3 is often omitted because the magnetic field sensor is often placed on the upper chest plane in magnetocardiography.
• the magnetic field time series data obtained from each sensor j is B j (t), and the spatial filter coefficient of the poxel i corresponding to each sensor output (B j (t) is / 3.
• the spatial filter coefficient is determined, the current density at each poxel i can be obtained, and a three-dimensional current density distribution can be obtained over the entire corner's fast-dissolving target.
• the SAM Synthetic Aperture
• MU SIC Multiple Signal Classification
• the virtual sensor output calculated in real time for each pixel obtained by using the spatial filter coefficient by the SAM or MU SIC method has the advantage of having a very high real-time property.
• Synthetic Aperture Magnetometry SAM "is described in detail. MU SIC was published on January 25, 1997 by Hiroshi Hara and Shinya Kuriki," Magnetic Brain Science-SQUID Measurement and Medical Application-”(Ohm Pp. 117-119 of the Company.
• the first arithmetic unit 2 generates time-series data indicating the three-dimensional current density distribution in the heart to be analyzed from the magnetic field distribution data generated by the magnetic field distribution measuring device 1 and displays the data. Applied to one input of device 4.
• the second arithmetic unit 3 shown in FIG. 2 is provided with an electrocardiogram synchronization trigger in advance by using another tomography diagnostic device (not shown), for example, an MR I method, an X-ray CT method, an echocardiogram method, a myocardial SPECT method, or the like.
• Image data of a plurality of slice images (for example, about a dozen or so images at 5 mm pitch) of the same subject's chest photographed with the camera is input.
• the second arithmetic unit 3 processes (captures) the data of the plurality of slice images, performs three-dimensional perspective transformation from a predetermined viewpoint, and generates second data indicating an anatomical image.
• Techniques for forming a three-dimensional anatomical image from a plurality of slice images in this manner are well known. For example, Japanese Patent Application Laid-Open No. H11-12828, International Publication W ⁇ 98 / 15 It is disclosed in detail in Japanese Patent Publication No. So the details here I will not explain it.
• the second arithmetic unit 3 generates second data indicating a three-dimensional anatomical image of the chest near the heart of the same subject, and supplies the second data to the other input of the display device 4.
• the display device 4 shown in FIG. 2 displays the three-dimensional anatomical image of the subject's chest formed based on the second data from the second arithmetic device 3 on the three-dimensional anatomical image from the first arithmetic device 2.
• the images showing the three-dimensional current density distribution in the myocardium formed based on the data of 1 are superimposed and displayed.
• FIGS.7A and 7B are diagrams showing real-time display modes of the three-dimensional current density distribution superimposed on the three-dimensional anatomical image displayed by the display device 4, respectively.
• the current density distribution changes over time with the transition of time.
• Each of Figures 7A and 7B is a three-dimensional image obtained by interpolating about five tomographic images obtained by slicing the subject's chest at a 5-mm pitch, for example, and illustrating the depth of the actual display image. It is difficult to express above.
• a diagram constituting each image is represented by a plurality of overlapping diagrams, a three-dimensional image having a sense of depth formed by synthesizing a plurality of slice images. It can be inferred that this is a typical anatomical image.
• the upper side of the tomographic image is the front of the human body, and the lower side is the back.
• Each of the tomographic images in Figs. 7A and 7B is a tomographic image viewed from the lower part ⁇ (foot side).
• the set of circles indicated by A represents the three-dimensional current density distribution superimposed on the three-dimensional corneal-necropsy image.
• the size indicates the magnitude of the current density.
• the magnitude of the current density can be displayed by shading a specific color on the screen.
• FIG. 8 shows a tomographic image extracted at a certain depth of a three-dimensional anatomical image having a depth as shown in FIGS. 7A and 7B, and is displayed in the same manner.
• the set represents the current density distribution on the tomographic image.
• the physician can determine the current density in the myocardium on the anatomical image.
• the relative positional relationship of the distribution can be accurately grasped.
• the displayed current density distribution indicates an abnormality
• the position, size, and shape of the myocardial injury site or the viable myocardial site can be accurately diagnosed.
• FIG. 9 is a flowchart showing a method for identifying the current density distribution in the myocardium, which is executed by the cardiac magnetic field diagnostic device according to Embodiment 1 described above.
• step S1 the magnetic field distribution measuring device 1 performs non-contact magnetic measurement at a plurality of coordinates on the human chest, generates a plurality of time-series data, and records the data if necessary.
• the above-described arithmetic operation by the SAM or MU SIC in the first arithmetic unit 2 can be executed on time-series data supplied in real time.
• step S2 the second arithmetic unit 3 performs an interpolation operation (three-dimensional perspective transformation from a predetermined viewpoint) on a plurality of MRI images photographed in advance with an ECG synchronization trigger, and performs three-dimensional Obtain anatomical images.
• an interpolation operation three-dimensional perspective transformation from a predetermined viewpoint
• step S3 the initial time of the analysis is set to t s , the end time of the analysis is set to t e , and the time interval of the angular analysis is set to ⁇ t.
• step S4 the analysis is started by substituting the initial time t s for the analysis time t. Then, in step S5, the following processing is performed until the analysis time t reaches the end time t e .
• step S6 the first arithmetic unit 2 processes the cardiac magnetic field distribution data at the specified analysis time by the SAM method or the MU SIC method to obtain intramyocardial current density distribution data.
• step S7 the actual myocardial current density is obtained from the actual volume of the myocardial tissue and the calculated current density distribution. That is, the intracardiac muscle current density distribution data calculated in step S6 is corrected to a value closer to the actual myocardial current density.
• step S8 the display device 4 superimposes and displays the current density in the myocardium on the anatomical image subjected to three-dimensional perspective transformation from a predetermined viewpoint.
• step S9 ⁇ t is added to the analysis time t.
• FIG. 10 is a flowchart showing a process according to the modification of the first embodiment, and is the same as the flowchart shown in FIG. 9 except for the following points.
• step S10 information on the presence / absence of myocardial damage and the degree of myocardial damage at the site is obtained from the information on myocardial damage current contained in the database 5 based on the corrected myocardial current density obtained in step S7 And display them on the display device 4 at the same time.
• the current density distribution is three-dimensionally displayed on the anatomical image of the heart, but in this modified example, the myocardium of the left and right ventricles is further expressed by anatomical factors of the heart.
• the area is divided into a plurality of arbitrary areas based on functional factors, and the current density distribution for each area is calculated.
• a method of dividing the region a method of dividing the left and right ventricles into arbitrary multiple regions by focusing on the anatomical characteristics of the heart, and a method of dividing the left ventricle into multiple arbitrary regions by focusing on the anatomical characteristics of the coronary artery
• a method of dividing into regions Other than this, for example, a method of obtaining a density curve every 6 degrees from the ventricular septum in a radiating manner, creating a profile curve, and further creating a functional diagram of voltage and conduction time can be considered.
• FIG. 11 is a diagram schematically illustrating a state of region division focused on the position of a coronary artery, which is an anatomical feature, as one mode of region division.
• the region division of the myocardium is divided into a region controlled by the anterior descending branch of the left coronary artery, a region controlled by the left circumflex, and a region controlled by the right coronary artery. Is being done. Then, the myocardial current density is calculated in each of these regions.
• FIG. 12 is a flowchart showing a process according to a further modification of the first embodiment.
• FIG. 9 is the same as the flowchart shown in FIG. 9 except for the following points.
• step S11 the myocardium is divided into regions governed by each branch of the coronary artery in the three-dimensional anatomical image obtained in step S2, as shown in FIG. Then, in step S12, the myocardial current density of each region divided in step S11 is obtained from the myocardial current density calculated in step S7. Therefore, in addition to the three-dimensional display of the current density distribution according to the first embodiment, it is possible to easily three-dimensionally identify the region including the myocardial lesion site in the left and right ventricles.
• Embodiment 1 of the present invention a three-dimensional image showing the current density distribution in the myocardium obtained by noninvasive magnetic measurement on the chest of a subject using a SQUID magnetometer
• physicians can safely, quickly and accurately determine the location, size, shape, and degree of disability of the affected or surviving myocardial site that shows abnormal current density distribution.
• the identification can be performed three-dimensionally, and the burden on the patient can be reduced.
• no radioisotope is used for the inspection, it is possible to carry out the inspection continuously without leaving the sun.
• the left and right ventricles are divided into multiple regions based on anatomical or functional factors, and the myocardial current density in each region is calculated. Diagnosis can be made easily, and it becomes easy to examine treatment methods. In particular, when performing treatment using a catheter ablation method using a high frequency, it is possible to significantly narrow down the target area of the electrophysiological examination performed using a force catheter in advance, and the examination time performed while performing fluoroscopy is reduced. It can be significantly reduced. As a result, the annual X-ray dose to physicians and radiologists can be significantly reduced.
• Embodiment 1 described above a large number of subjects are required to form an anatomical image. It was necessary to obtain a layer image, and examinations such as the MRI method and the X-ray CT method were performed in advance. As a result, the number of examinations was increased, burdening patients, and treatments directly related to the examination could not be performed.
• Embodiment 2 of the present invention eliminates the necessity of forming an anatomical image, thereby reducing the number of examinations and enabling a live-myocardium diagnostic apparatus and a surviving myocardium by magnetic field measurement that can be performed directly in connection with diagnosis and examination.
• the present invention provides a myocardial analysis method.
• FIG. 13 is a functional block diagram schematically showing a configuration of a viable myocardial diagnosis device using magnetic field measurement according to the second embodiment of the present invention.
• magnetic field distribution measuring apparatus 1 has already been described in relation to Embodiment 1, and will not be described again here.
• the magnetic field distribution time-series data generated by the magnetic field distribution measuring device 1 is supplied to the arithmetic unit 6, and the arithmetic unit 6 performs the above-described SAM method or MU SIC based on the given magnetic field distribution time-series data. It generates data showing the three-dimensional current density distribution in the myocardium by using a calculation method such as the method. Based on the generated three-dimensional current density distribution data, the arithmetic unit 6 generates data indicating an excitation (stimulus) propagation path in the cardiac muscle during a period corresponding to the QRS group from the P wave of the electrocardiogram, Are generated by being superimposed on each other and given to the display device 7.
• the display device 7 corresponds to an image showing the current density distribution in the myocardium indicated by the data generated by the arithmetic device 6 and corresponding to the period of the QRS group from the P wave of the electrocardiogram similarly obtained by the arithmetic device 6.
• the excitement propagation path is superimposed and displayed on a three-dimensional image. As a result, it is possible to three-dimensionally identify the abnormal current density distribution in the myocardium of the ventricle without using an anatomical image as in the first embodiment.
• a database 5 including determination information on the relationship between the current density distribution in the myocardium and the myocardial injury current is provided.
• FIG. 14 is a block diagram showing a more specific configuration of the surviving myocardial diagnosis device based on magnetic field measurement according to the second embodiment of the present invention shown in FIG.
• the magnetic field distribution measuring device 1 is the same as the magnetic field distribution measuring device 1 described with reference to FIGS. 2 and 3, and thus the description thereof is omitted here.
• the magnetic field distribution time-series data output from the magnetic field distribution measurement device 1 is The arithmetic unit 6 converts the magnetic field distribution time-series data into current density distribution time-series data by the SAM method or the MU SIC method described with reference to FIG.
• an electrocardiograph 21 for recording the electrocardiogram of the subject 12 is provided, and the electrocardiogram waveform data of the subject 12 measured by the electrocardiograph 21 is provided to the arithmetic unit 6.
• the waveform of the electrocardiogram is correlated with the generated current density distribution, it is possible to correlate the electrocardiogram with events occurring in the heart.
• FIG. 15A is a diagram schematically showing a normal stimulus propagation path in the heart
• FIG. 15B shows an electrocardiogram waveform for one beat.
• the sinoatrial node of the heart functions as a pacemaker that determines the heart rate, and fires at regular intervals (the timing of the P wave of the electrocardiogram) to generate a pulse.
• This pulse is transmitted to the atrioventricular node via a predetermined stimulus propagation path, and after a certain time delay, the pulse is transmitted from the His (bundle) bundle to the lower ventricle via the Purkinje fiber system, and the heart muscle is immediately blown. Contraction occurs.
• the transmission of the Purkinje fiber stimulus from the His bundle corresponds to the isovolumic systole, which is the period of the QRS complex of the electrocardiogram.
• the arithmetic unit 6 indicates the stimulus propagation path as a normal route as shown in FIG. Generate image data.
• Such an image of the stimulus propagation path shown in FIG. 15A can be used as a template display instead of the premature anatomical image of the first embodiment. That is, even if there is no three-dimensional anatomical image as in the first embodiment, if the stimulus propagation path of the normal route shown in FIG. An injured myocardial site or a viable myocardial site showing a high current density distribution can be easily anatomically correlated by a physician, and its position, size, shape, and degree can be identified.
• the arithmetic unit 6 in FIG. 14 generates data indicating the generated current density distribution by superimposing on the display of the stimulus propagation path as such a template.
• the image data is synthesized with the image data of the above-described template and provided to the display device 7.
• the display device 7 shown in FIG. 14 displays an image showing the current density distribution on the basis of the data from the arithmetic device 6 so as to be superimposed on a normal stimulus propagation path as a template. This allows the physician to make an anatomical mapping of the damaged or surviving myocardium.
• FIG. 16 is an example of a screen actually displayed by the display device 7, in which an image of a portion showing an abnormal current density distribution is displayed so as to be superimposed on a normal stimulus propagation path as a template.
• the physician can easily make an anatomical correspondence based on the relative positional relationship of the current density distribution to the normal stimulus propagation path as a template shown in Fig. 16, and the damaged myocardial site in the left and right ventricles Alternatively, the location, size, shape, and degree of a viable myocardial site can be identified.
• FIGS. 17 and 18 are diagrams each showing a method for analyzing the electrophysiologically viable myocardium in the myocardium, which is performed by the electrophysiologically viable myocardial diagnostic apparatus according to Embodiment 2 described above.
• step S 21 non-contact magnetic measurement is performed at a plurality of coordinates on the human chest using the magnetic field distribution measuring device 1 to generate and record a plurality of magnetic field time series data. I do.
• step S22 the initial time of the analysis is determined as the P wave start time t sP of the electrocardiogram, the analysis end time is determined as the QRS group end time t eQRS of the electrocardiogram, and the analysis time interval is defined as ⁇ t. .
• step S23 t sP which is the start time of the P wave is substituted for the analysis time t.
• step S25 the arithmetic device 6 processes the cardiac magnetic field distribution data at the designated analysis time t by the SAM method or the MU SIC method to generate intramyocardial current density distribution data.
• step S26 the current density distribution data in the myocardium The image subjected to the two-dimensional perspective transformation is displayed.
• step S27 ⁇ t is added to the analysis time t, and the process returns to step S24 to determine whether the end time t eQRS has been reached. If it is determined that the end time t eQRS has been reached, an image showing the stimulus propagation path, which is the normal route shown in Fig. 15A, is associated with the period corresponding to the QRS group from the P wave in the electrocardiogram waveform. The data has been obtained.
• step S 2 8 in FIG. 1 determine the initial time of the analysis and t s, defines the end time of the analysis and t e, defined as delta t the analysis time interval.
• step S29 the initial time t s is substituted for the analysis time t.
• step S 3 to analyze the time t is determined that it has reached the end time t e, the following steps S 3 1 to S 3 4 is performed.
• step S31 the arithmetic device 6 processes the cardiac magnetic field distribution data at the specified analysis time t by the SAM method or the MU SIC method to generate intramyocardial current density distribution data.
• step S32 an actual myocardial current density is obtained from the actual volume of the myocardial tissue and the calculated current density distribution. That is, the current density distribution data calculated in step S31 is corrected to a value closer to the actual myocardial current density.
• step S33 the myocardial current density data is displayed so as to be superimposed on the image of the normal stimulus propagation path subjected to three-dimensional perspective transformation from a predetermined viewpoint.
• step S34 ⁇ t is added to the analysis time t, and step S3
• FIG. 19 is a flowchart showing processing according to such a modification of the second embodiment, and is the same as the flowchart shown in FIG. 18 except for the following points.
• step S35 based on the corrected myocardial current density obtained in step S32, Information on the presence or absence of a myocardial injury and the extent of the injury at the site is extracted and displayed on the display device 7 at the same time.
• the myocardium of the left and right ventricles is divided into arbitrary plural regions based on anatomical or functional factors of the heart. It is also possible to calculate the current density distribution for each region. Since the mode of area division and the like have already been described in the first embodiment, they will not be repeated here.
• FIG. 20 is a flowchart showing a process according to such a modification of the second embodiment, and is the same as the flowchart shown in FIG. 18 except for the following points.
• step S36 the position of the ventricular septum is determined from the information on the stimulus propagation path from the His bundle obtained by the arithmetic unit 6 to immediately before the Purkinje fiber system, so that based on the predetermined angle, The process of dividing the ventricle into multiple regions based on the atrioventricular node is performed. Then, in step S37, the myocardial current density calculated for each region can be obtained from the actual volume and the current density distribution of each region of the tissue divided as described above.
• an image showing the current density distribution in the myocardium obtained by non-invasive magnetic measurement on the chest of a subject using a SQUID magnetometer is used as a template.
• the position, size, shape, and location of the myocardial lesion or abnormal myocardium that shows abnormal current density distribution without superimposing on other anatomical images Doctors will be able to safely, quickly and accurately identify the degree in three dimensions.
• the burden on the patient can be significantly reduced.
• a preliminary examination for obtaining an anatomical image can be omitted.
• the myocardial lesions in the left and right ventricles are three-dimensionally determined. Diagnosis is possible, making it easier to consider treatment methods You.
• the target area of the electrophysiological examination performed using a catheter can be significantly narrowed in advance, so that the examination time performed while performing fluoroscopy can be significantly reduced. it can. As a result, the annual X-ray dose to physicians and radiologists can be significantly reduced.
• the current density distribution in the myocardium obtained by noninvasive magnetic measurement on the chest of a patient can be visually displayed on a three-dimensional anatomical image. It is possible to three-dimensionally identify the location, size, shape, and degree of a myocardial lesion site or a surviving myocardial site exhibiting an abnormal current density distribution.
• the injured myocardium or viable myocardium can be diagnosed non-invasively, and a quick and safe examination can be performed without imposing a burden on the patient.
• a quick and safe examination can be performed without imposing a burden on the patient.
• continuous inspection can be performed, which has the effect of reducing costs.
• a myocardial lesion site or a viable myocardial site can be diagnosed three-dimensionally.
• the target area for electrophysiological examination can be significantly narrowed in advance, and the X-ray exposure of doctors and radiologists can be significantly reduced. Plays.
• the anatomical image is displayed by superimposing the current density distribution on the normal stimulus propagation circuit from the sinoatrial node of the same subject to the His bundle and the Purkinje fiber system and displaying the current density distribution in three dimensions. Without this, it is possible to three-dimensionally identify the location, size, shape, and extent of the damaged or surviving myocardial site in the ventricle. That is, it is possible to omit an examination for obtaining an anatomical image, and to provide a more cost-effective diagnosis.
• the position, size, shape, and degree of a myocardial lesion site or a viable myocardial site exhibiting abnormal current density distribution can be identified three-dimensionally, which is useful for non-invasive diagnosis of injured myocardium or viable myocardium, and for medical treatment by catheter ablation using high frequency.

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