SYSTEM AND METHOD FOR CORRECTING ECG SIGNALS IN MRI ENVIRONMENT - Patent application

Abstract

A system and method are provided for correcting electrocardiograms (ECGs) affected by magnetohydrodynamic (MHD) effects. The system and method derive patient information from images captured by a camera and use this information to calculate T-wave correction factors used to counteract the amplification of T-waves due to MHD effects. While a patient undergoes an MRI scan, an ECG monitor captures the patient's ECG signal and a camera captures a series of patient images. The series of images are provided to an image processing unit (IPU). The IPU processes the images to derive patient information and calculate T-wave correction factors. The IPU then attenuates the amplitude of T-waves in the captured ECG signal to generate a corrected ECG signal. This corrected ECG signal is then used by the MRI scanner for more accurate gated images.

Description

[Technical field]

[0001] The present disclosure is generally directed to systems and methods for correcting electrocardiogram (ECG) signals affected by magnetohydrodynamic effects. [Background technology]

[0002] Magnetic resonance imaging (MRI) scanners utilize magnetic fields, magnetic field gradients, and radio waves to generate a series of patient images. To focus on the relevant images, MRI scanners may use gating or triggering mechanisms. One such mechanism may be an electrocardiogram (ECG). An ECG signal includes several waves, segments, complexes, and intervals. In particular, the R wave is often used to gate MRI image acquisition, storage, and / or transmission.

[0003] In an MRI environment, gradients generated by an MRI scanner can induce electrical potentials in a patient's vasculature as blood circulates, known as the magnetohydrodynamic (MHD) effect. The MHD effect can amplify or distort the T waves of an ECG signal to such an extent that MRI gating mechanisms can confuse the amplified or distorted T waves for R waves. Thus, MHD can result in gating errors in MRI gated images. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there is a need in the art for an improved system for gating MRI image acquisition based on ECG signals captured in an MRI environment. [Means for solving the problem]

[0005] The present disclosure is generally directed to systems and methods for correcting electrocardiogram (ECG) signals affected by magnetohydrodynamic (MHD) effects. The MHD effects are caused by a patient undergoing magnetic resonance imaging (MRI). The systems and methods derive patient information (such as heart rate) from images captured by a camera and use this patient information to calculate a T-wave correction factor. The T-wave correction factor is used to counteract the amplification or distortion of T-waves due to the MHD effects. The MRI scanner can then use the corrected ECG signal for more accurate gated images.

[0006] The system includes an MRI scanner, an ECG monitor, an MRI-compatible camera, and an image processing unit (IPU). While the patient undergoes an MRI scan, the ECG monitor captures the patient's ECG signal. At the same time, the camera captures a series of patient images. The series of images captured by the camera are provided to the IPU. The IPU processes the images to derive patient information and calculates a T-wave correction factor. The IPU then attenuates the amplitude (or otherwise compensates for distortions) of T-waves in the captured ECG signal based on the T-wave correction factor to generate a corrected ECG signal. This corrected ECG signal is then used by the MRI scanner for more accurate gated images, since the adjusted T-waves are no longer confused with R-waves.

[0007] In general, in one aspect, a magnetic resonance imaging gating system is provided that includes an ECG monitor configured to capture an ECG signal of a patient.

[0008] The magnetic resonance imaging gating system further includes a camera configured to capture a series of patient images. According to one example, the camera is a high frame rate camera or a vital signs camera. According to a further example, the camera has a frame rate of at least 1,000 frames per second.

[0009] According to one example, a series of patient images are captured of the patient's neck region.

[0010] The magnetic resonance imaging gating system further includes an image processing unit. The image processing unit (IPU) is configured to determine a T-wave correction factor. The T-wave correction factor is determined based on the series of patient images. According to one example, the T-wave correction factor is further based on a patient heart rate derived from the series of patient images.

[0011] According to one example, the T wave correction factor is further based on the diameter of the carotid artery. Additionally, the T wave correction factor may be further based on the blood flow velocity in the carotid artery.

[0012] According to one example, the T-wave correction factor is further based on the magnetic field incident on the patient, which in this example may be generated by an MRI scanner.

[0013] According to one example, the T-wave correction factor is further based on the angle between the magnetic field incident on the patient and the direction of blood flow in the carotid artery.

[0014] The IPU is further configured to generate a corrected ECG signal. The corrected ECG signal is generated based on the captured ECG signal and the T-wave correction factor.

[0015] The magnetic resonance imaging gating system further includes an MRI scanner configured to generate a gated MRI image set. The gated MRI image set is generated based on the corrected ECG signal. According to one example, the MRI scanner generates the gated MRI image set further based on one or more R waves of the corrected ECG signal.

[0016] In general, in another aspect, a system for MHD effect correction for an ECG signal is provided that includes a camera configured to capture a series of patient images, the system further including an image processing unit configured to (1) determine a T-wave correction factor based on the series of patient images, and (2) generate a corrected ECG signal based on the ECG signal and the T-wave correction factor.

[0017] In general, in another aspect, a method is provided for correcting ECG signals for MHD effects. The method includes capturing, via a camera, a series of patient images. The method further includes determining, via a processor, a T-wave correction factor based on the series of patient images. The method further includes generating, via a processor, a corrected ECG signal based on the captured ECG signal and the T-wave correction factor. According to one example, the method further includes capturing, via an ECG monitor, the captured ECG signal. According to one example, the method further includes generating, via a magnetic resonance imaging (MRI) scanner, a gated MRI image set based on the corrected ECG signal.

[0018] In various implementations, a processor or controller may be associated with one or more storage media (collectively referred to herein as "memory", e.g., volatile and non-volatile computer memory such as RAM, PROM, EPROM, EEPROM, floppy disks, compact disks, optical disks, magnetic tapes, SSDs, etc.). In some implementations, the storage media may be encoded with one or more programs that, when executed on one or more processors and / or controllers, perform at least some of the functions described herein. The various storage media may be fixed within a processor or controller or may be transportable such that one or more programs stored thereon may be loaded into the processor or controller to implement various aspects as discussed herein. The term "program" or "computer program" is used in a generic sense herein to refer to any type of computer code (e.g., software or microcode) that may be used to program one or more processors or controllers.

[0019] It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in more detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, the subject matter of the claims at the end of this disclosure is intended to be part of the inventive subject matter disclosed herein. It should also be understood that the terminology expressly used herein and that may also appear in any disclosures incorporated by reference shall have the meaning most consistent with the particular concepts disclosed herein.

[0020] These and other aspects of the various embodiments will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0021] In the drawings, as in the literature, like reference numbers generally refer to the same parts throughout the different drawings and the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of various embodiments. [Brief description of the drawings]

[0022] [Figure 1] 1 is a system diagram of a magnetic resonance imaging (MRI) gating system according to an example. [Diagram 2] 1 is a diagram of an embodiment of a magnetic resonance imaging gating system, according to an example. [Diagram 3] FIG. 2 is a schematic diagram of an image processing unit (IPU) according to an example. [Figure 4] 1 is a flowchart of a method for correcting an electrocardiogram (ECG) signal, according to an example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present disclosure generally relates to a system and method for correcting electrocardiograms (ECGs) affected by magnetohydrodynamic (MHD) effects. The MHD effects are caused by patients undergoing magnetic resonance imaging (MRI). The system and method derive patient information (such as heart rate) from images captured by a camera and use this patient information to calculate a T-wave correction factor. The T-wave correction factor is used to counteract the amplification of T-waves due to the MHD effects. The MRI scanner can then use the corrected ECG signal for more accurate gated images.

[0024] The system includes an MRI scanner, an ECG monitor, an MRI compatible camera, and an image processing unit (IPU). While the patient undergoes an MRI scan, the ECG monitor captures the patient's ECG signal. At the same time, the camera captures a series of patient images. The camera can be a high frame rate camera or a vital signs camera aimed at the patient's neck region. More specifically, the camera can be aimed at one of the patient's carotid arteries.

[0025] The series of images captured by the camera are provided to an image processing unit. The IPU processes the images to derive patient information and calculates T-wave correction factors. The IPU may also receive aspects of the patient information from other sources. Prior to deriving the patient information, the image processing unit may stabilize and / or denoise one or more of the patient images.

[0026] First, the IPU determines the patient's heart rate based on the patient images. The heart rate is determined by analyzing the skin proximate to the patient's carotid artery. The IPU can use the patient's heart rate to determine the velocity of blood flowing through the carotid artery. The IPU also receives and / or derives information regarding the diameter of the carotid artery.

[0027] The IPU also receives information about the magnetic field generated by the MRI scanner. Specifically, this information can include the magnitude of the magnetic field, as well as the angle between the magnetic field and the direction of blood flow. The magnetic field information can be provided by a sensor or can be provided to the IPU directly from the MRI scanner.

[0028] The IPU calculates a T-wave correction factor using the above information. The IPU then attenuates the amplitude of the T-waves of the captured ECG signal based on the T-wave correction factor to generate a corrected ECG signal. This corrected ECG signal is then used by the MRI scanner for more accurate gated images since the adjusted T-waves are no longer confused with R-waves.

[0029] 1 shows a system diagram of a magnetic resonance imaging gating system 100. The magnetic resonance imaging gating system 100 generates a gated MRI image set 126 based on a corrected ECG signal 118 generated by the IPU 106 based on a patient image 116, captured by the camera 104, and generated by the ECG monitor 102.

[0030] A patient 200 is inserted into the bore of an MRI scanner 108. In some instances, the entire patient 200 enters the bore, while in other instances, only relevant parts of the patient (head, limbs, etc.) enter the bore. The MRI scanner 108 uses magnetic fields, magnetic field gradients, and radio waves to generate a series of MRI images of the patient 200.

[0031] The ECG monitor 102 captures an ECG signal 110 on the patient 200 while the patient 200 is inserted into the MRI scanner 108 and undergoes an MRI scan. The ECG signal 110 may be based on one or more leads connected to one or more electrodes placed on the patient 200. The ECG monitor 102 may be located inside or outside the MRI scanner 108 depending on the application. As shown in FIG. 1, the ECG signal 110 transmitted from the ECG monitor 102 to the IPU 106 includes T waves that are amplified due to the MHD effect.

[0032] Also, while the patient 200 is undergoing an MRI scan, a camera 104 disposed inside the MRI scanner 108 captures a series of patient images 116. The camera 104 may be a high frame rate camera, such as a camera having a frame rate of at least 1,000 frames per second. Alternatively, the camera 104 may be a vital signs camera. As shown in FIG. 2, the camera 104 may be configured to capture an image 116 of the patient's neck region 202, including one of the patient's carotid arteries 204.

[0033] The magnetic resonance imaging gating system 100 further includes an IPU 106. The IPU 106 is in wired or wireless communication with the MRI scanner 108, the ECG monitor 102, and the camera 104. The IPU receives the patient image 116 from the camera 104, the ECG signal 110 from the ECG monitor 102, and information about the magnetic field 122 from the MRI scanner 108. Alternatively, information about the magnetic field 122 may be captured and communicated to the IPU 106 via sensors located within the MRI scanner 108. The combination of the IPU 106 and the camera 104 may be considered an MHD effects compensation system 50.

[0034] The primary purpose of the IPU 106 is to calculate a T-wave correction factor 114 for the ECG signal 110. The T-wave correction factor 114 is applied to the ECG signal 110 to compensate for amplified T-waves due to MHD effects. An exemplary T-wave correction algorithm 180 is shown in Equation 1: U = |B|*|v|*d*sin(q) (1) It is shown as:

[0035] In Equation 1, U is the voltage induced by the MHD effect, |B| is the magnitude 124 of the magnetic field 122 incident on the patient 200 during an MRI scan, |v| is the blood flow velocity 208 through the carotid artery 204 of the patient 200, d is the diameter 206 of the carotid artery 204, and q is the angle 128 between the lines of the magnetic field 122 and the blood flow direction 210 in the carotid artery 204. In this example, U is the T wave correction factor 114. Furthermore, in this example, d is orthogonal to B and v. In other examples, U can be further processed to determine the T wave correction factor 114. The value of the T wave correction factor 114 can then be subtracted from the T waves of the ECG signal 110 to generate a corrected ECG signal 118.

[0036] Upon receiving the series of patient images 116, the IPU 108 may pre-process the images 116 using noise removal and / or frame stabilization algorithms 182. Once the images 116 are pre-processed, the IPU 106 further processes the images 116 to determine the heart rate 120 of the patient 200. The patient heart rate 120 may be determined by analyzing the movement of the patient's skin around one of the carotid arteries 204 via the images 116 captured by the high frame rate camera 104.

[0037] The IPU 108 may also use the patient's heart rate 120 to determine the blood flow rate 208. The blood flow rate 208 may be determined in a number of ways, such as by taking into account the patient's blood pressure.

[0038] The diameter 206 of the carotid artery 204 may be provided to the IPU 106 by the patient record or by a medical professional operating the magnetic resonance imaging gating system 100. In a further example, the diameter 206 of the carotid artery 204 may be derived from the patient image 116.

[0039] The magnitude 124 of the magnetic field 122 incident on the patient 200 as well as the angle 128 between the magnetic field 122 and the blood flow direction 208 in the carotid artery may be provided to the IPU 106 directly by the MRI scanner 108 or via sensors within the MRI scanner 108 .

[0040] Once the IPU 106 receives or determines all of the variables in Equation 1, the IPU 106 determines a T-wave correction factor 114. An exemplary T-wave correction factor 114 may be 1 mV or less. In one example, the IPU 106 then determines a corrected ECG signal 118 by subtracting the T-wave correction factor 114 from the captured ECG signal 110. In another example, additional calculations are performed using the T-wave correction factor 114 and the captured ECG signal 110 to generate the corrected ECG signal 118. As shown in FIG. 1, the corrected ECG signal 118 has a T-wave of a typical amplitude.

[0041] The corrected ECG signal 118 is provided to the MRI scanner 108 for gated imaging. In gated imaging, the MRI scanner 108 continuously generates MRI images, but stores and / or transmits only those MRI images that correspond to a gating event or trigger. In one example, the MRI scanner 108 generates one or more gated images 126 based on the R-waves 130 of the corrected ECG signal 118. Thus, each of the gated images 126 corresponds to the R-waves 130 of one cycle of the ECG signal 110. Applying the T-wave correction factor 114 to the ECG signal 110 prevents the MRI scanner 108 from confusing the amplified T-waves with the R-waves 130, thus preventing gating and / or triggering errors.

[0042] In one example, the MRI scanner 108 provides the gated image 126 to a user interface 130 for display. The user interface 130 may be an aspect of the MRI scanner 108 itself or may be a component of a stand-alone device such as a personal computer. The MRI scanner 108 may communicate with the user interface 130 via wired or wireless communication. In a further example, the gated image may be stored in a memory of the MRI scanner and / or in a memory of a stand-alone device such as a personal computer or a network server.

[0043] 2 shows a diagram of several aspects of a magnetic resonance imaging gating system, including an MRI scanner 108, a camera 104, and an ECG monitor 102. A patient 200 is inserted into the bore of the MRI scanner 108 along with the camera 104. While the patient undergoes an MRI scan, the camera 104 captures a series of patient images 112 of the patient's 200 neck region 202 (which may include one of the patient's carotid arteries 204). Also during the MRI scan, the ECG monitor 102 captures an ECG signal 110. As shown in FIG. 2, this ECG signal 110 has T waves that are amplified during the MRI scan due to the MHD effect.

[0044] 3 shows a schematic diagram of the IPU 106. The IPU 106 includes a processor 175 for executing a T-wave correction algorithm 180 (as in Equation 1), as well as noise removal and / or frame stabilization algorithms. The IPU 106 further includes a memory 150 for storing data received by other components of the magnetic resonance imaging gating system 100 and / or generated by the processor 175. The IPU 106 further includes a transceiver 190 for communicating (directionally or bidirectionally) with the camera 104, the ECG monitor 102, and the MRI scanner 108.

[0045] In general, in another aspect, with reference to FIG. 4, a method 500 for correcting ECG signals for MHD effects is provided. The method 500 includes capturing 510 a series of patient images via a camera. The method 500 further includes determining 520 a T-wave correction factor based on the series of patient images via a processor. The method 500 further includes generating 530 a corrected ECG signal based on the captured ECG signal and the T-wave correction factor via a processor. According to one example, the method 500 further includes capturing 540 a captured ECG signal via an ECG monitor. According to one example, the method 500 further includes generating 550 a gated MRI image set based on the corrected ECG signal via a magnetic resonance imaging (MRI) scanner.

[0046] All definitions should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms as defined and used herein.

[0047] The indefinite articles "a" and "an," as used herein in the specification and the claims, unless clearly indicated to the contrary, should be understood to mean "at least one."

[0048] The phrase "and / or," as used herein in the specification and claims, should be understood to mean "either or both" of the elements so conjoined, i.e., elements that are present in some cases concomitantly and in other cases not conjointly. Multiple elements listed with "and / or" should be construed in the same manner, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the "and / or" clause, whether related or unrelated to those elements specifically identified.

[0049] In the specification and claims, as used herein, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when separating items in a list, "or" or "and / or" should be interpreted as being inclusive, i.e., including at least one, and more than one, of a number or list of elements and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as "only one of" or "exactly one of," or when used in the claims, "consisting of," refer to the inclusion of exactly one element of a number or list of elements. In general, the term "or," as used herein, when preceded by terms of exclusivity, such as "either," "one of," "only one of," or "exactly one of," should be interpreted merely to indicate exclusive alternatives (i.e., "one and the other, but not both").

[0050] As used herein in the specification and claims, the phrase "at least one," in a reference to a list of one or more elements, should be understood to mean at least one selected from any one or more elements in the list of elements, but not necessarily including at least one of each and every element specifically listed in the list of elements, and not excluding any combination of elements in the list of elements. This definition allows for elements, whether related or unrelated to the specifically identified elements, optionally being present other than the elements specifically identified in the list of elements to which the phrase "at least one" refers.

[0051] It should also be understood that, unless clearly indicated to the contrary, in any method claimed herein that includes more than one step or act, the order of the method steps or acts is not necessarily limited to the order in which the method steps or acts are recited.

[0052] In the claims, as well as in the specification, all transitional phrases such as "comprise," "including," "carry," "have," "contain," "related to," "sustaining," "composed of," and the like, are to be understood to be open-ended, i.e., to mean inclusive but not exclusive. Only the transitional phrases "consisting of" and "consisting essentially of" are closed or semi-closed transitional phrases, respectively.

[0053] Examples of the subject matter described above can be implemented in any of numerous ways. For example, some aspects may be implemented using hardware, software, or a combination thereof. When any aspect is implemented at least partially in software, the software code may be executed on any suitable processor or collection of processors, whether provided on a single device or computer, or distributed across multiple devices / computers.

[0054] The present disclosure may be implemented as a system, method, and / or computer program product at any possible level of technical detail of integration. The computer program product may include a computer-readable storage medium (or media) having computer-readable program instructions thereon for causing a processor to perform aspects of the present disclosure.

[0055] A computer-readable storage medium may be a tangible device that can hold and store instructions for use by an instruction execution device. A computer-readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of computer-readable storage media includes portable computer diskettes, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), static random access memories (SRAMs), portable compact disk read-only memories (CD-ROMs), digital versatile disks (DVDs), memory sticks, floppy disks, mechanically encoded devices such as punch cards, or raised structures in grooves with instructions recorded thereon, and any suitable combination of the foregoing. A computer-readable storage medium, as used herein, should not be interpreted as being a transitory signal in itself, such as an electric wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a wave guide or other transmission medium (e.g., light pulses passing through a fiber optic cable), or an electrical signal transmitted through a wire.

[0056] The computer readable program instructions described herein can be downloaded to each computing / processing device from a computer readable storage medium or to an external computer or storage device over a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical transmission fiber, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium in the respective computing / processing device.

[0057] The computer readable program instructions for carrying out the operations of the present disclosure may be either source code or object code written in any combination of one or more programming languages, including assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuits, or object oriented programming languages ​​such as Smalltalk, C++, and procedural programming languages ​​such as the "C" programming language or similar programming languages. The computer readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer, partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or wide area network (WAN), or the connection may be made to an external computer (e.g., via the Internet using an Internet Service Provider). In some examples, electronic circuitry including, for example, a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may execute computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry to perform aspects of the present disclosure.

[0058] Aspects of the present disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to examples of the present disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer readable program instructions.

[0059] The computer readable program instructions may be provided to a processor of a special purpose computer or other programmable data processing apparatus to generate a machine such that the instructions, executed via the processor of the computer or other programmable data processing apparatus, create means for performing the functions / operations specified in the flowchart and / or block diagram blocks or blocks. These computer readable program instructions may also be stored on a computer readable storage medium capable of directing a computer, programmable data processing apparatus, and / or other device to function in a particular manner, such that a computer readable storage medium having instructions stored therein includes an article of manufacture including instructions implementing aspects of the functions / operations specified in the flowchart and / or block diagram blocks or blocks.

[0060] The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to generate a computer-implemented process that executes on the computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device such that the instructions, executing on the computer, other programmable data processing apparatus, or other device, perform the functions / operations specified in the flowchart and / or block diagram blocks or blocks.

[0061] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible embodiments of systems, methods, and computer program products according to various examples of the present disclosure. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, or part of instructions, comprising one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions shown in the blocks may occur out of the order shown in the figures. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or may be executed in reverse order depending on the functionality involved in the blocks. It should also be noted that each block of the block diagrams and / or flowchart diagrams, as well as combinations of blocks in the block diagrams and / or flowchart diagrams, may be implemented by a dedicated hardware-based system that executes the specified functions or operations, or executes a combination of dedicated hardware and computer instructions.

[0062] Other implementations are within the scope of the following claims and other claims to which the applicant may be entitled.

[0063] Although various examples have been described and illustrated herein, one of ordinary skill in the art will readily envision various other means and / or structures for performing the functions and / or obtaining one or more of the advantages described herein, and each such variation and / or modification is deemed to be within the scope of the examples described herein. More generally, one of ordinary skill in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the particular application or applications for which the teachings are used. One of ordinary skill in the art will recognize, or be able to ascertain, using no more than routine experimentation, many equivalents to the specific examples described herein. Thus, it will be understood that the foregoing examples are presented by way of example only, and that, within the scope of the appended claims and their equivalents, the present disclosure is directed to each individual feature, system, term, material, kit, and / or method described herein. Furthermore, any combination of two or more such features, systems, terms, materials, kits, and / or methods is included within the scope of the present disclosure, if such features, systems, terms, materials, kits, and / or methods are not mutually inconsistent.

Claims

1. 1. A magnetic resonance imaging (MRI) gating system, comprising: an electrocardiogram (ECG) monitor configured to capture an ECG signal of the patient; a camera configured to capture a series of patient images, the series of patient images capturing a neck region of the patient; determining a T wave correction factor based on the series of patient images; generating a corrected ECG signal based on the captured ECG signal and the T-wave correction factor; An image processing unit configured as follows: an MRI scanner configured to generate a gated MRI image set based on the corrected ECG signals; A magnetic resonance imaging gating system comprising:

2. The magnetic resonance imaging gating system of claim 1 , wherein the camera is a high frame rate camera or a vital signs camera.

3. 10. The magnetic resonance imaging gating system of claim 1, wherein the camera has a frame rate of at least 1000 frames per second.

4. The magnetic resonance imaging gating system of claim 1 , wherein the T-wave correction factor is further based on a patient heart rate derived from the series of patient images.

5. The magnetic resonance imaging gating system of claim 1 , wherein the T wave correction factor is further based on a magnitude of a magnetic field incident on the patient.

6. The magnetic resonance imaging gating system of claim 5 , wherein the magnetic field is generated by the MRI scanner.

7. The magnetic resonance imaging gating system of claim 1 , wherein the T wave correction factor is further based on a diameter of the carotid artery.

8. 8. The magnetic resonance imaging gating system of claim 7, wherein the T-wave correction factor is further based on blood flow velocity in the carotid artery.

9. 8. The magnetic resonance imaging gating system of claim 7, wherein the T-wave correction factor is further based on an angle between a magnetic field incident on the patient and a direction of blood flow in the carotid artery.

10. 2. The magnetic resonance imaging gating system of claim 1, wherein the MRI scanner generates the gated MRI image set further based on one or more R waves of the corrected ECG signal.

11. 1. A magnetohydrodynamic (MHD) effect correction apparatus for an electrocardiogram (ECG) signal, comprising: a camera configured to capture a series of patient images, the series of patient images capturing a neck region of the patient; determining a T wave correction factor based on the series of patient images; generating a corrected ECG signal based on the ECG signal and the T wave correction factor; An image processing unit configured as follows: A magnetohydrodynamic effect correction device comprising:

12. 1. A method for compensating an electrocardiogram (ECG) signal for magnetohydrodynamic (MHD) effects, comprising: capturing a series of patient images via a camera, the series of patient images capturing a neck region of the patient; determining, via a processor, a T wave correction factor based on the series of patient images; generating, via the processor, a corrected ECG signal based on the captured ECG signal and the T-wave correction factor; The method comprising:

13. The method of claim 12 , further comprising acquiring the captured ECG signal via an ECG monitor.

14. 13. The method of claim 12, further comprising generating, via a magnetic resonance imaging (MRI) scanner, a gated MRI image set based on the corrected ECG signals.

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