General Electric Company

John F Schenck

William A Edelstein

Charles L Dumoulin

Robert David Darrow

Ronald Dean Watkins

Steven P Souza

Christopher Judson Hardy

Paul Arthur Bottomley

Eddy Benjamin Boskamp

Peter B Roemer

William D Barber

Ek Tsoon Tan

Randy Otto John Giaquinto

Xiaofeng Liu

David R Eisner

Albert Amos Montillo

Harvey E Cline

Sayed-Amr A El-Hamamsy

William E Lorensen

Otward M Mueller

Kenneth William Rohling

William Macomber Leue

Cecil E Hayes

Howard Roscoe Hart, Jr

John Andrew Mallick

Rowland W Redington

Moayyed A Hussain

Kirby Gannett Vosburgh

Samuel M Blumenfeld

Richard L St Peters

Cornelius Jan Von Morze

The system and method of the invention combines target image intensity into a maximum likelihood estimate (MLE) framework as in STAPLE to take advantage of both intensity-based segmentation and statistical label fusion based on atlas consensus and performance level, abbreviated iSTAPLE. The MLE framework is then solved using a modified expectation-maximization algorithm to simultaneously estimate the intensity profiles of structures of interest as well as the true segmentation and atlas performance level. The iSTAPLE greatly extends the use of atlases such that the target image need not have the same image contrast and intensity range as the atlas images.

Systems and methods for image segmentation using target image intensity

Systems and methods for image segmentation using a deformable atlas are provided. One method includes obtaining one or more target images, obtaining one or more propagated label probabilities for the one or more target images, and segmenting the one or more target images using a cost function of a deformable atlas model. The method further includes identifying segmented structures within the one or more target images based on the segmented one or more target images.

Systems and methods for image segmentation using a deformable atlas

Methods and apparatus for fabricating a magnetic resonance imaging (MRI) gradient coil for generating magnetic field gradients are provided. The method includes determining a pattern of gradient current paths on a surface using a set of stream functions oriented in at least one of a z-gradient, a y-gradient; and an x-gradient, and arranging conductive material to define a current path that conforms to the determined gradient current paths.

Methods and systems for fabricating magnetic resonance gradient coils

A radio frequency (RF) coil assembly for a very high field Magnetic Resonance Imaging (MRI) system is provided comprising a plurality of conductors arranged cylindrically and disposed about a cylindrical patient bore tube of the MRI system and a plurality of capacitive elements for electrically interconnecting the plurality of conductors at respective ends of the conductors. The conductors have a width selected for the RF coil assembly to resonate at substantially high frequencies. A very high field Magnetic Resonance Imaging (MRI) system is provided that comprises a RF coil assembly adapted to resonate at substantially high frequencies, a RF coil shield assembly and a plurality of RF drive power cables.

RF coil for very high field magnetic resonance imaging

A radio frequency (RF) coil assembly for a very high field Magnetic Resonance Imaging (MRI) system is provided. The RF coil assembly comprises a plurality of conductors arranged cylindrically and disposed about a patient bore tube of the MRI system. Each of the conductors is configured for the RF coil assembly to resonate at substantially high frequencies. Further, the RF coil assembly comprises a plurality of capacitive elements disposed between and connecting respective ends of the conductors and further disposed in a spaced-apart relationship with the patient bore tube. The capacitive elements are for electrically interconnecting the plurality of conductors at the respective ends of the conductors.

RF coil for reduced electric field exposure for use in very high field magnetic resonance imaging

A quadrature coil suitable for use with an open frame MRI system provides crossing pairs of arrays of parallel conductor elements, respectively. Compact configuration is provided through use of an isolating circuit for incorporating parasitic capacitances at the resonance frequency of the coil into a blocking parallel resonance. Termination of the parallel conductor elements may be accomplished by equal impedance node connectors formed from branching pairs of conductors or a triangular least resistance connection form. RF shields are provided by pairs of conductive sheets containing eddy current reducing slots aligned with the parallel conductors elements of the coil.

Radio frequency coil for open magnetic resonance imaging system

The present invention comprises a whole body RF coil system for use with an open magnetic resonance (MR) imaging system. The RF coil system comprises first and second quadrature RF coil sets positioned on opposing sides of an imaging volume. Each RF coil set comprises similarly-structured, multiple RF coils. Each quadrature RF coil comprises a first and second plurality of primary path conductor segments, and first and second return path conductors, symmetrically disposed about a centerline at specified distances. The first and second plurality of primary path conductor segments are positioned in a first plane that is substantially spaced apart from a second plane, further from the imaging volume, containing the first and second return path conductors. The conductors within each of the first and second set of primary path conductor segments are adapted to have a predetermined current amplitude ratio. Upon energization of the first and second RF coil sets in quadrature to generate a circular, polarized B,field, the positioning of the conductors and the predetermined current amplitude ratio provide a desired homogeneity within the imaging volume and a desired sensitivity drop-off outside of the imaging volume.

RF body coil

Instruments are constructed of a carbon fiber material optionally doped with a doping agent such as iron oxide, the instrument having a magnetic susceptibility being adjusted to a portion of a subject being imaged. Therefore there is little effect upon the lines of magnetic flux and the magnetic field homogeneity, reducing distortion in an MR image. These carbon fiber instruments exhibit virtually no magnetic torsional forces when inserted into a magnetic field. This is important, for example when the instrument is a scalpel. Doped carbon fiber has minimal affect on radiofrequency fields. The instruments do not affect the homogeneity of an applied homogeneous magnetic field or an applied radiofrequency field. Doped carbon fiber exhibits a rigidity large enough to allow construction of high strength instruments such as biopsy needles. It also has the ability to retain a sharp edge, allowing construction of scalpels and cutting instruments. Doped carbon fiber surgical instruments may be used inside a magnetic field during magnetic resonance imaging, thereby allowing interactive internal images to be produced and displayed to a surgeon during surgery. A method is also disclosed for imaging a control material and then the instrument to determine the type and amount of doping agent required.

Carbon fiber magnetic resonance compatible instruments

Magnetic field gradient coils, such as those typically employed in magnetic resonance (MR) imaging employ folded loop current paths in which a first section carries current along a path close to an imaging volume. This produces a magnetic field gradient within the imaging volume. A second section, being a further radial distance from the imaging volume, carries current in a return path, in a substantially opposite current direction as the first section, thereby reducing stray magnetic fields outside of the second section. The second preferable has the same current pattern, but is slightly larger to contain magnetic fields at the fringes. A third section connects each turn of the coils in the first section to a corresponding turn of coils in the second section. This third section is disposed in a partially radial direction to connect the first and second sections. The present invention employs the return current, which is typically wasted current, to `shield` the gradient coils, reducing stray magnetic fields outside of the gradient coils, and therefore replace a second layer of `shielding` coils typically used in conventional systems. This results in a great power savings, and increased ability to rapidly change magnetic field gradients, while reducing claustrophobia, acoustic noise and a possibility of nerve stimulation.

Transverse gradient coil

A tracking system in which radiofrequency signals emitted by an invasive device such as a catheter, are detected and used to measure the position and orientation of the invasive device. The invasive device has a transmit coil attached near its end and is driven by a low power RF source to produce a dipole electromagnetic field that can be detected by an array of receive coils distributed around a region of interest. The position and orientation of the device as determined by the tracking system are superimposed upon independently acquired Medical Diagnostic images, thereby minimizing the radiographic exposure times. One or more invasive devices can be simultaneously tracked.

Tracking system to follow the position and orientation of a device with

A magnetic resonance (MR) imaging system for use in a medical procedure employs an open main magnet allowing access to a portion of a patient within an imaging volume, for producing a main magnetic field over the imaging volume; a set of open gradient coils which provide magnetic fields gradients over the imaging volume without restricting access to the imaging volume; a radiofrequency coil set for transmitting RF energy into the imaging volume to nutate nuclear spins within the imaging volume and receive an MR response signal from the nuclear spins; and a pointing device for indicating the position and orientation of a plane in which an image is to be acquired; an image control means for operating power supplies for the gradient coils and the RF coils to acquire an MR signal from the desired imaging plane; and a computation unit for constructing an image of the desired imaging plane. The MR imaging system is intended to operate to provide images to a physician during medical procedures to guide the physician in his procedures.

Magnetic resonance imaging system with pointing device

A tracking system in which radiofrequency signals emitted by an invasive device such as a catheter are detected and used to measure the position and orientation of the invasive device within a subject. Detection of the radiofrequency signals is accomplished with coils having sensitivity profiles which vary approximately linearly with position. The invasive device has a transmit coil attached near its end and is driven by a low power RF source to produce a dipole electromagnetic field that can be detected by an array of receive coils distributed around a region of interest of the subject. The position and orientation of the device as determined by the tracking system are superimposed upon independently acquired Medical Diagnostic images, thereby minimizing the diagnostic exposure times. One or more invasive devices can be simultaneously tracked.

An antenna for NMR imaging of the eye of a patient includes a small circular or oval surface coil which is locatable immediately adjacent to the eye of the patient and supported by a member having a shape contoured to fit in the region between the zygomatic and supra-orbital arches of the face. The supporting member may be a disc supporting a whole-eye surface coil anterior of the eye, or may be a contact-lens-like member supporting a fine wire surface coil substantially in contact with the anterior orbital aspect.

Antennae for high-resolution magnetic resonance imaging of the eye

Apparatus for detecting movement of an anatomical sample undergoing NMR imaging uses at least one optical sensor, each having an output responsive to the intensity of received illumination and each directed to view a selected portion of sample; and apparatus for monitoring the output of each sensor to detect a change therein responsive to movement of the sample.

Motion detector for high-resolution magnetic resonance imaging

A magnetic resonance system for both imaging and spectroscopy of a sample of non-magnetic material (such as a portion of the human anatomy and the like) at one static magnetic field magnitude in excess of 0.7 Tesla (T), utilizes a superconducting magnet having a room-temperature bore of diameter sufficiently large to place therein not only the desired sample but also a set of gradient magnetic field-producing coils and at least one radio-frequency coil for exciting and/or receiving response signals from the sample to be examined. The entire magnetic system has suitably-small temporal and positional field variations to allow imaging to be accomplished at the resonant frequencies of nuclei including .sup.1 H, .sup.13 C, .sup.19 F, .sup.23 Na and .sup.31 P. The system includes a novel interface subsystem, itself including a novel gradient signal switching circuit, for acquiring imaging data in relatively short time intervals.

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Schenectady, NY, United States of America

John F Schenck