摘要:
In a method or system for magnetic resonance imaging based temperature monitoring for real-time feedback to a physician for a cryoablation therapy of a lesion which creates an ice ball of the lesion to induce cell death, the magnetic resonance imaging system, using proton resonance frequency imaging, obtains a real-time temperature image of the ice ball of the lesion undergoing the cryoablation therapy and the adjacent surrounding tissue. By use of an algorithm, correcting temperature errors at a border of the ice ball are corrected in the real-time image, the temperature error correction correcting susceptibility contrast errors caused by a distortion of the local magnetic field at the border of the ice ball.
摘要:
In a method or system for magnetic resonance imaging based temperature monitoring for real-time feedback to a physician for a cryoablation therapy of a lesion which creates an ice ball of the lesion to induce cell death, the magnetic resonance imaging system, using proton resonance frequency imaging, obtains a real-time temperature image of the ice ball of the lesion undergoing the cryoablation therapy and the adjacent surrounding tissue. By use of an algorithm, correcting temperature errors at a border of the ice ball are corrected in the real-time image, the temperature error correction correcting susceptibility contrast errors caused by a distortion of the local magnetic field at the border of the ice ball.
摘要:
In a method to determine a background phase in phase values of a phase image data set that is acquired from an examination subject, wherein the background phase is determined in a partial region of the phase image data set, the phase image data set of the examination subject is acquired, and a substantially closed, planar contour is established in the phase image data set around the partial region, the planar contour having a contour area with a width of at least one pixel of the phase image data set. The phase values in the partial region are determined with the assumption that the spatial curve of the background phase is a harmonic or quasi-harmonic function, the phase values of the pixels in the partial region being determined based on the phase values in the planar contour.
摘要:
In a method to determine a background phase in phase values of a phase image data set that is acquired from an examination subject, wherein the background phase is determined in a partial region of the phase image data set, the phase image data set of the examination subject is acquired, and a substantially closed, planar contour is established in the phase image data set around the partial region, the planar contour having a contour area with a width of at least one pixel of the phase image data set. The phase values in the partial region are determined with the assumption that the spatial curve of the background phase is a harmonic or quasi-harmonic function, the phase values of the pixels in the partial region being determined based on the phase values in the planar contour.
摘要:
In a magnetic resonance (MR) method and apparatus for spatially resolved determination of at least one MR parameter that influences an MR signal detected in an MR measurement of a region of an examination subject, first complex image data and second complex image data, respectively acquired with different acquisition coils and at different echo times in an echo imaging sequence, are provided to a processor. The different image data sets have complex image points that correspond with each other with regard to the imaged volume element of the examination subject. The MR parameter is determined in the processor for at least a portion of these image points by determination of an image point vector respectively for the first and second echo times and by combining the image point vectors to at least partially compensate echo time-independent phase or magnitude portions in the acquired image data.
摘要:
In a method and system for phase-sensitive magnetic resonance imaging, a respective, complex image data set provided to a processor for each of at least two different echo times, the complex image data sets for the different echo times having been reconstructed from magnetic resonance data that acquired for the different echo times using an echo imaging sequence, at least one complex division image data set is determined in the processor by complex division of the complex image data sets for the two different echo times. The two different echo times define an echo time difference, so the resulting complex division image data set has phase components that are dependent on the echo time difference.
摘要:
In a method and system for phase-sensitive magnetic resonance imaging, a respective, complex image data set provided to a processor for each of at least two different echo times, the complex image data sets for the different echo times having been reconstructed from magnetic resonance data that acquired for the different echo times using an echo imaging sequence, at least one complex division image data set is determined in the processor by complex division of the complex image data sets for the two different echo times. The two different echo times define an echo time difference, so the resulting complex division image data set has phase components that are dependent on the echo time difference.
摘要:
In a magnetic resonance (MR) method and apparatus for spatially resolved determination of at least one MR parameter that influences an MR signal detected in an MR measurement of a region of an examination subject, first complex image data and second complex image data, respectively acquired with different acquisition coils and at different echo times in an echo imaging sequence, are provided to a processor. The different image data sets have complex image points that correspond with each other with regard to the imaged volume element of the examination subject. The MR parameter is determined in the processor for at least a portion of these image points by determination of an image point vector respectively for the first and second echo times and by combining the image point vectors to at least partially compensate echo time-independent phase or magnitude portions in the acquired image data.
摘要:
In a method and system for administering a dispersible medical agent to a subject, a volume of medical agent is delivered in vivo to a subject in a substantially non-dispersed state, at a localized site in tissue of the subject. Contemporaneously with administration of the medical agent to the localized site, energy from an energy source is introduced into only adjacent tissue surrounding the localized site. The energy produces a cellular modification of the adjacent tissue that makes the adjacent tissue substantially impermeable to passage of the medical agent therethrough, so the medical agent is encapsulated and is prevented from dispersing into tissue outside of the encapsulation.
摘要:
In a method and magnetic resonance (MR) system to create an MR magnitude image data set and a phase image data set of an examination subject, first echo signals in a first raw MR data set are detected after a first echo time TE1 and at least second echo signals in at least one second raw MR data set are detected after a second echo time TE2 that is longer than TE1, a magnitude image data set is generated on the basis of the first raw MR data set and the at least one second raw MR data set with averaging of the first and the at least one second raw MR data set, and the phase image data set is generated based on the phase information contained in the at least two raw MR data sets, with averaging of the respective phase information contained in the at least two raw MR data sets.