Abstract: A method for producing an image of an object located in the field of view of a Magnetic Resonance (MR) imaging system including determining a center of an echo, shifting the data elements of the raw matrix by whole positions to align the center of the echo, multiplying the shifted raw matrix by a low pass filter, Fourier transforming the filtered matrix, dividing each nonzero pixel of the low resolution complex image by its magnitude, calculating a blending function shifted by the determined fractional echo position, multiplying each data element of each row of the raw matrix by corresponding blending function coefficient values, performing a two-dimensional Fourier transform in row directions and column directions, multiplying the complex image by a complex conjugate of the phase map and extracting the real part of the complex numbers in the phase corrected image to provide the image of the object.

Abstract: A method for producing an image of an object located in the field of view of a Magnetic Resonance (MR) imaging system including determining a center of an echo, shifting the data elements of the raw matrix by whole positions to align the center of the echo, multiplying the shifted raw matrix by a low pass filter, Fourier transforming the filtered matrix, dividing each nonzero pixel of the low resolution complex image by its magnitude, calculating a blending function shifted by the determined fractional echo position, multiplying each data element of each row of the raw matrix by corresponding blending function coefficient values, performing a two-dimensional Fourier transform in row directions and column directions, multiplying the complex image by a complex conjugate of the phase map and extracting the real part of the complex numbers in the phase corrected image to provide the image of the object.

Abstract: In a method and apparatus for magnetic resonance (MR) imaging of an object, and in particular MR imaging that yields images sensitive to molecular diffusion, undesired image artifacts induced by the rhythmic motion of the apparatus are reduced by manipulating the amplitude, phase, and timing of the diffusion encoding gradient pulses in a manner that interrupts, diminishes, or cancels the rhythmic motion. The residual vibration is evaluated manually or automatically to make such manipulations.

Abstract: In a method and apparatus for magnetic resonance (MR) imaging of an object, and in particular MR imaging that yields images sensitive to molecular diffusion, undesired image artifacts induced by the rhythmic motion of the apparatus are reduced by manipulating the amplitude, phase, and timing of the diffusion encoding gradient pulses in a manner that interrupts, diminishes, or cancels the rhythmic motion. The residual vibration is evaluated manually or automatically to make such manipulations.

Abstract: A method and apparatus for visualizing an interventional device in a body using a magnetic resonance (MR) imager. In operation an MR pulse sequence is applied to the body so as to develop MR signals, which are processed so as to acquire one or more images. An operator of the imager uses a hands-free device to control parameters of the applied pulse sequence so as to cause the images to show an intensity distortion artifact in the area of the interventional device that is increased as compared to intensity distortion artifact in conventional MR images; and, after an image distortion which is expected to be produced by the interventional device is seen, the operator changes the applied pulse sequence parameters, in a “hands-free” manner, so that said one or more acquired images show an intensity distortion artifact in the area of the interventional device that is reduced as compared to said increased intensity distortion.

Abstract: A method and apparatus for magnetic resonance (MR) imaging of a moving object, and in particular MR imaging by retrospectively selecting and sorting the MR data acquired with the known prior positions of an orthopedic joint. A mechanical apparatus limits the motion of the joint while an optical or electronic apparatus determines the instantaneous articulation position of the joint, for example its rotational angle. Either partial or complete MR data are acquired asynchronously with respect to various positions of joint movement, and the MR data are then retrospectively selected and sorted to form images of the joint at the various articulated positions. This retrospective selecting and sorting allows sharp images to be acquired using MR data acquired over several flexions and extensions of the joint, regardless of the periodicity or velocity of its motion.