194 results about "Magnetic Resonance Imaging Scan" patented technology

An implantable biocompatible lead that is also compatible with a magnetic resonance imaging scanner for the purpose of diagnostic quality imaging is described. The implantable electrical lead comprises a plurality of coiled insulated conducting wires wound in a first direction forming a first structure of an outer layer of conductors of a first total length with a first number of turns per unit length and a plurality of coiled insulated conducting wires wound in a second direction forming a second structure of an inner layer of conductors of a second total length with a second number of turns per unit length. The first and the second structures are separated by a distance with a layer of dielectric material. The distance and dielectric material are chosen based on the field strength of the MRI scanner. The lead may further comprise a conducting layer formed by coating a material consisting of medium conducting particles in physical contact with each other and a mechanically flexible, biocompatible layer forming an external layer of lead and in contact with body tissue or body fluids.

An antenna module, that is compatible with a magnetic resonance imaging scanner for the purpose of diagnostic quality imaging, is adapted to be implanted inside an animal. The antenna module comprises an electrically non-conducting, biocompatible, and electromagnetically transparent enclosure with inductive antenna wires looping around an inside surface. An electronic module is enclosed in an electromagnetic shield inside the enclosure to minimize the electromagnetic interference from the magnetic resonance imaging scanner.

A system and method for using magnetic resonance imaging to increase the accuracy of electrophysiologic procedures is disclosed. The system in its preferred embodiment provides an invasive combined electrophysiology and imaging antenna catheter which includes an RF antenna for receiving magnetic resonance signals and diagnostic electrodes for receiving electrical potentials. The combined electrophysiology and imaging antenna catheter is used in combination with a magnetic resonance imaging scanner to guide and provide visualization during electrophysiologic diagnostic or therapeutic procedures. The invention is particularly applicable to catheter ablation, e.g., ablation of atrial fibrillation. In embodiments which are useful for catheter ablation, the combined electrophysiology and imaging antenna catheter may further include an ablation tip, and such embodiment may be used as an intracardiac device to both deliver energy to selected areas of tissue and visualize the resulting ablation lesions, thereby greatly simplifying production of continuous linear lesions. The invention further includes embodiments useful for guiding electrophysiologic diagnostic and therapeutic procedures other than ablation. Imaging of ablation lesions may be further enhanced by use of MR contrast agents. The antenna utilized in the combined electrophysiology and imaging catheter for receiving MR signals is preferably of the coaxial or “loopless” type. High-resolution images from the antenna may be combined with low-resolution images from surface coils of the MR scanner to produce a composite image. The invention further provides a system for eliminating the pickup of RF energy in which intracardiac wires are detuned by filtering so that they become very inefficient antennas. An RF filtering system is provided for suppressing the MR imaging signal while not attenuating the RF ablative current. Steering means may be provided for steering the invasive catheter under MR guidance. Other ablative methods can be used such as laser, ultrasound, and low temperatures.

An implantable electronic medical device is compatible with a magnetic resonance imaging (MRI) scanner. The device has a housing with exterior walls, each formed by a dielectric substrate with electrically conductive layers on interior and exterior surfaces. A series of slots divide each layer into segments. Segmenting the layers provides high impedance to eddy currents produced by fields of the MRI scanner, while capacitive coupling of the segments provides radio frequency shielding for components inside the housing. Electrical leads extending from the housing have a pair of coaxially arranged conductors and traps that attenuate currents induced in the conductors by the fields of the MRI scanner.

An antenna module, that is compatible with a magnetic resonance imaging scanner for the purpose of diagnostic quality imaging, is adapted to be implanted inside an animal. The antenna module comprises an electrically non-conducting, biocompatible, and electromagnetically transparent enclosure with inductive antenna wires looping around an inside surface. An electronic module is enclosed in an electromagnetic shield inside the enclosure to minimize the electromagnetic interference from the magnetic resonance imaging scanner.

A system and method for facilitating RF pulse sequence generation and modification and for real-time sequence input modification for use in conjunction with magnetic resonance imaging equipment. A graphical user interface is provided through a display coupled to a digital computer operating as the primary control system for a magnetic resonance imaging scanner and associated hardware. Through the graphical user interface, an operator may choose or design sequences of radiofrequency pulses, gradient waveforms and other input parameters for the magnetic resonance imaging apparatus. Real-time information is also communicated to the operator through the graphical user interface allowing for real-time manipulation of the magnetic resonance imaging inputs and for displaying the magnetic resonance response thereto.

An implantable biocompatible lead that is also compatible with a magnetic resonance imaging scanner for the purpose of diagnostic quality imaging is described. The implantable electrical lead comprises a plurality of coiled insulated conducting wires wound in a first direction forming a first structure of an outer layer of conductors of a first total length with a first number of turns per unit length and a plurality of coiled insulated conducting wires wound in a second direction forming a second structure of an inner layer of conductors of a second total length with a second number of turns per unit length. The first and the second structures are separated by a distance with a layer of dielectric material. The distance and dielectric material are chosen based on the field strength of the MRI scanner. The lead may further comprise a conducting layer formed by coating a material consisting of medium conducting particles in physical contact with each other and a mechanically flexible, biocompatible layer forming an external layer of lead and in contact with body tissue or body fluids.

The invention provides a compressed sensing theory-based reconstruction method of a magnetic resonance random sampled K space data image. The reconstruction method applies a contourlet conversion and iterative soft thresholding method to realize reconstruction of a magnetic resonance image. The method comprises the following steps: collecting K space data in a magnetic resonance image scanner according to a preset observation matrix phi to generate a measurement value, and keeping y; acquiring y from a coil of the magnetic resonance image scanner, and transmitting y to a computer; and finallyconstructing a same phi, constructing any orthogonal transformation psi, and recovering from y by adopting a compressed sensing theory-based magnetic resonance random sampled K space data image reconstruction method according to reconstruction. According to the method, scanning time is saved, quick imaging is realized, high-quality reliable image information is provided to medical nuclear magnetic resonance imaging detection, and solid theoretical and practical foundation is established for further development and large-scale popularization and application of the medical imaging detection technology.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

A system and method for facilitating RF pulse sequence generation and modification and for real-time sequence input modification for use in conjunction with magnetic resonance imaging equipment. A graphical user interface is provided through a display coupled to a digital computer operating as the primary control system for a magnetic resonance imaging scanner and associated hardware. Through the graphical user interface, an operator may choose or design sequences of radiofrequency pulses, gradient waveforms and other input parameters for the magnetic resonance imaging apparatus. Real-time information is also communicated to the operator through the graphical user interface allowing for real-time manipulation of the magnetic resonance imaging inputs and for displaying the magnetic resonance response thereto.

An apparatus for monitoring a conscious subject, such as a rat or human, in a strong magnetic field, such as that generated by a magnetic resonance imaging (MRI) scanner, includes sensors and wireless transmitter. The sensors detect physiological parameters of the subject, and the transmitter sends a wireless signal representing the parameters. A system for monitoring a conscious subject in a magnetic field includes a wireless monitor, wireless interface, and computer. The wireless monitor includes the sensors, filters, microcontroller, and wireless transmitter. The wireless interface receives the signal from the wireless monitor and transmits a corresponding signal to the computer. A method of monitoring a conscious subject in a strong magnetic field includes disposing the sensor in the magnetic field, sensing a physiological parameter from the subject, providing a sensed signal representing the parameter, disposing a wireless transmitter on the subject, and transmitting a signal representing the sensed parameter.

A system for detecting electromagnetic noise in a magnetic resonance imaging (MRI) scanner environment includes an antenna configured to detect electromagnetic noise. The antenna includes a first conducting loop and a second conducting loop oriented perpendicularly to the first conducting loop. The system also includes a noise correction system coupled to the antenna and configured to receive noise signals from the antenna.

A magnetic resonance imaging (MRI) system, comprising: a magnetic resonance imaging scanner comprising: a main magnet providing a substantially uniform main magnetic field B0 for a subject under observation; and a radio frequency (RF) coil configured to irradiate a radio frequency (RF) pulse into a region of interest of the subject under observation, wherein the RF pulse comprises a base pulse comprising an adiabatic pulse having a first bandwidth time product (BWTP), wherein the RF pulse selectively suppresses magnetic resonance signals from more than one chemical component or more than one spatial region within the region of interest of the subject under observation, and wherein the adiabatic pulse is characterized by an amplitude modulation function and a frequency modulation function.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

The invention relates to the technical field of medical experimental facilities, and discloses a small animal brain three-dimensional positioning system for magnetic resonance imaging scanning equipment. The system comprises a magnetic compatibility small animal brain three-dimensional positioning device used for conducting brain three-dimensional positioning on the head of a small animal and a magnetic resonance small animal radio frequency coil device which is used for receiving a magnetic resonance radio frequency signal in the X axis direction and transmitting the signal to a magnetic resonance imaging system. According to the system, in the piercing implementation process, magnetic resonance scanning can be carried out on an experimental animal, the magnetic resonance radio frequency signal is received through the small animal radio frequency coil, the signal is transmitted to the magnetic resonance imaging system, a magnetic resonance scanning image can be utilized for guiding and monitoring the piercing process, the magnetic resonance imaging scanning equipment can be utilized for guiding a small animal three-dimensional positioning operation or conducting positioning experiments such as piercing and stimulation exertion.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

The invention relates to signal noise removing method based on parts of frequency spectrum data signal reconstruction. It includes the following steps: collecting intact K spatial data G(kx, ky) from magnetic resonance imaging scanner; taking out parts of frequency spectrum data to reconstruct many observing signals; utilizing multiple observing signal averaging to process image signal noise removing. The invention combines the advantages of the multiple and single observing signal noise removing method that it can save scanning time, increase signal noise ratio. This method is effective and practical, has stable and reliable working performance, can be used in general signal noise removing.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

A magnetic resonance imaging (MRI) system, comprising: a MRI scanner; a signal processing system in communication with the magnetic resonance imaging scanner to receive magnetic resonance (MR) signals for forming magnetic resonance images of a subject under observations; a data storage unit in communication with the signal processing system, wherein the data storage unit contains database data corresponding to a soft tissue region of the subject under observation. The database data includes information identifying at least one soft tissue substructure encompassed by the soft tissue region of the subject under observation. The signal processing system is adapted to process MR signals received from the MRI scanner to automatically identify at least one soft tissue substructure encompassed by the soft tissue region of the subject under observation.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

A low noise imaging apparatus for producing Magnetic Resonance (MR) images of a subject (200) and for substantially minimizing acoustic noise generated during imaging is provided. The imaging apparatus comprises a magnet assembly (4,6,7), a gradient coil assembly (3), and a RF coil assembly (2), wherein at least one of the magnet assembly, the gradient coil assembly and the RF coil assembly are configured to reduce the generation and transmission of acoustic noise.

To prepare magnetization for steady state magnetic resonance imaging, magnetic resonance is primed using a parameterized priming sequence (60). The parameterized priming sequence (60) has a spectral offset parameter value (40) corresponding to a spectral offset of the steady state imaging. Subsequent to the priming, steady state magnetic resonance imaging data at the first spectral offset is acquired using a magnetic resonance imaging scanner (10). A reconstruction processor (44) reconstructs the imaging data to generate an image representation. Preferably, the parameterized priming sequence (60) includes a longitudinal priming sequence (62) that prepares longitudinal magnetization in a state approximating a steady state longitudinal magnetization. A spoiler sequence (64) spoils transverse magnetization while retaining longitudinal magnetization. A transverse priming sequence (66) prepares traverse magnetization in a state approximating a steady state transverse magnetization.

A phantom and method are provided for co-registering a magnetic resonance image and a nuclear medical image. The phantom includes a first housing defining a first chamber configured to receive a magnetic resonance material upon which magnetic resonance imaging can be performed in order to produce the magnetic resonance image. The phantom also includes three or more second housings configured to be attached to the first housing, where the second housings each define a second chamber configured to receive a radioactive material upon which nuclear imaging can be performed in order to produce the nuclear medical image and upon which the magnetic imaging can be performed in order to produce the magnetic resonance image. The first chamber has a volumetric capacity that is larger than a volumetric capacity of each second chamber.

A magnetic resonance imaging system includes a magnetic resonance imaging scanner (10) that performs an inversion recovery magnetic resonance excitation sequence (70) having a blood-nulling inversion time (60) determined based on a blood T1 value appropriate for a selected magnetic field and blood hematocrit, whereby magnetic resonance of blood is substantially nulled. The inversion recovery excitation sequence (70) includes an inversion radio frequency pulse (74) applied with a small or zero slice-selective magnetic field gradient pulse to avoid inflow effects, and an excitation radio frequency pulse (80). The inversion pulse (74) and excitation pulse (80) are separated by the inversion time (60). The magnetic resonance imaging scanner (10) subsequently performs a readout magnetic resonance sequence (72) or spectroscopy sequence to acquire a magnetic resonance signal from tissue other than the nulled blood. A reconstruction processor (44) generates a reconstructed image from the acquired magnetic resonance signal.

A magnetic resonance position and orientation marking system includes fiducial assembly ( 30 ) with at least three fiducial markers ( 31, 32, 33 ) each coupled with at least one magnetic resonance receive coil ( 70, 74, 80, 84 ). At least one of the fiducial markers has at least one of: (i) marker nuclei selectively excitable over <1>H fat and water resonance, 5 and (ii) a plurality of magnetic resonance receive coils ( 70, 84 ) coupled therewith. At least two magnetic resonance receive channels ( 40, 42 ) receive magnetic resonance signals from the at least three fiducial markers ( 31, 32, 33 ) responsive to excitation of magnetic resonance in said at least three fiducial markers by a magnetic resonance imaging scanner ( 10 ).

The invention relates to a method of selecting a set of coil elements from a multitude of physical coil elements comprised in a coil array for performing a magnetic resonance imaging scan of a region of interest.

Provided herein is a system and method for performing a magnetic resonance imaging scan using a MR scanner. The method can comprise receiving via a user interface a MR imaging protocol categorizable into a MR scan type of a predefined set of MR scan types. Further, the method can comprise querying a database by providing to the database scan information permitting the database to identify the MR scan type of the MR imaging protocol. The method can further comprise receiving from the database statistical information on the MR scan type which can include statistics on modifications of individual scan parameters of the MR scan type, and providing the statistical information to the user interface. Modifications of the MR imaging protocol can be received from the user interface, resulting in a modified MR imaging protocol, according to which the MR imaging scan can be performed.

A lead includes a conductor having a distal end and a proximal end and a resonant circuit connected to the conductor. The resonant circuit has a resonance frequency approximately equal to an excitation signal's frequency of a magnetic resonance imaging scanner or a resonance frequency not tuned to an excitation signal's frequency of a magnetic resonance imaging scanner so as to reduce the current flow through a tissue area, thereby reducing tissue damage. The resonant circuit may be included in an adapter that provides an electrical bridge between a lead a medical device such as an electrode, sensor, or signal generator. The resonant circuit may also be included directly in the housing of a medical device.

A contrast agent for magnetic resonance imaging comprising a complex of a paramagnetic cation, preferably Gd+3, Dy+3, and Fe+3 with three equivalents of a charge neutralizing chelator that provides a lipid soluble complex of the paramagnetic cation is described. The complex is retained intracellularly when introduced into a mammalian cell. A method of providing an image of an internal pathology of a patient by magnetic resonance imaging (MRI) by administering the MRI contrast agent or tagged cells to the patient and scanning the patient using magnetic resonance imaging to obtain visible images of the internal pathology of the patient is also set forth.