Various embodiments are described herein for an apparatus and a method for measuring and characterizing geometric distortions for a region of interest in images obtained using magnetic resonance. The method comprises deriving a computed set of 3D distortion vectors for a set of points within a region of interest covered by a phantom by using harmonic analysis to solve an associated boundary value problem based on boundary conditions derived from a measured set of 3D distortion vectors. The characterized image distortions may be used for various purposes such as for image correction or for shimming, for example.

In a method and test apparatus for determining a deviation in the homogeneity of a basic magnetic field of a magnetic resonance scanner, test vessels are positioned in a test plane that first and second positions along a direction in the scanner, and measurement data are acquired with the test vessels at said respective positions. The acquired measurement data are provided to a processor, wherein a deviation of the homogeneity of the basic magnetic field is determined based thereon.

In a method and test apparatus for determining a deviation in the homogeneity of a basic magnetic field of a magnetic resonance scanner, test vessels are positioned in a test plane that first and second positions along a direction in the scanner, and measurement data are acquired with the test vessels at said respective positions. The acquired measurement data are provided to a processor, wherein a deviation of the homogeneity of the basic magnetic field is determined based thereon.

A magnetic resonance imaging configuration and methodology to straighten and otherwise homogenize the field lines in the imaging portion, creating improved image quality. Through use of calibrated corrective coils, magnetic field lines can be manipulated to improve uniformity and image quality. Additionally, when the apparatus is composed of non-ferromagnetic materials, field strengths can be increased to overcome limitations of Iron-based systems such as by use of superconductivity. A patient positioning apparatus and methodology allows multi-positioning of a patient within the calibrated and more uniform magnetic field lines.

A magnetic resonance imaging configuration and methodology to straighten and otherwise homogenize the field lines in the imaging portion, creating improved image quality. Through use of calibrated corrective coils, magnetic field lines can be manipulated to improve uniformity and image quality. Additionally, when the apparatus is composed of non-ferromagnetic materials, field strengths can be increased to overcome limitations of Iron-based systems such as by use of superconductivity. A patient positioning apparatus and methodology allows multi-positioning of a patient within the calibrated and more uniform magnetic field lines.

Various embodiments are described herein for an apparatus and a method for measuring and characterizing geometric distortions for a region of interest in images obtained using magnetic resonance. The method comprises deriving a computed set of 3D distortion vectors for a set of points within a region of interest covered by a phantom by using harmonic analysis to solve an associated boundary value problem based on boundary conditions derived from a measured set of 3D distortion vectors. The characterized image distortions may be used for various purposes such as for image correction or for shimming, for example.

Various embodiments are described herein for an apparatus and a method for measuring and characterizing geometric distortions for a region of interest in images obtained using magnetic resonance. The method comprises deriving a computed set of 3D distortion vectors for a set of points within a region of interest covered by a phantom by using harmonic analysis to solve an associated boundary value problem based on boundary conditions derived from a measured set of 3D distortion vectors. The characterized image distortions may be used for various purposes such as for image correction or for shimming, for example.

A method for creating an image data set using a magnetic resonance system including at least two RF transmit coils includes, for each RF transmit coil, calculating a value for a susceptibility magnetic field gradient to be corrected from the G.sub.s map in combination with the B1 map of the RF transmit coil. The method includes, for each RF transmit coil, calculating a time delay of the excitation pulse. The method also includes calculating a complex weighting factor for scaling the pulse profile for each RF transmit coil to achieve an as uniform as possible deflection of the magnetization by the excitation pulse over the area under examination, and passing through the imaging sequence. The RF transmit coils each emit an excitation pulse with the calculated time delay and with a pulse profile scaled according to the calculated complex weighting factors.

A method for creating an image data set using a magnetic resonance system including at least two RF transmit coils includes, for each RF transmit coil, calculating a value for a susceptibility magnetic field gradient to be corrected from the G.sub.s map in combination with the B1 map of the RF transmit coil. The method includes, for each RF transmit coil, calculating a time delay of the excitation pulse. The method also includes calculating a complex weighting factor for scaling the pulse profile for each RF transmit coil to achieve an as uniform as possible deflection of the magnetization by the excitation pulse over the area under examination, and passing through the imaging sequence. The RF transmit coils each emit an excitation pulse with the calculated time delay and with a pulse profile scaled according to the calculated complex weighting factors.

A technology of improving image quality of a calculation image or parameter estimation accuracy even in a case where a method of simultaneously generating calculation images of a plurality of parameters is used is provided. Thus, by utilization of a reconstructed image in an optimal resolution of each parameter to be estimated, a value of the parameter is estimated and a calculation image that is a distribution of the value of the parameter is acquired. A reconstructed image in an optimal resolution is acquired by adjustment of a resolution of a reconstructed image acquired in an optimal resolution of an estimation parameter with the highest optimal resolution among parameters to be estimated in scanning. Alternatively, in scanning, only a reconstructed image used for calculation of a predetermined parameter to be estimated is acquired in an optimal resolution of the parameter to be estimated.