4899109 Method and apparatus for automated magnetic field shimming in magnetic resonance spectroscopic imaging

4899109 Method and apparatus for automated magnetic field shimming in magnetic resonance spectroscopic imaging

VI New quire alternately magnetic resonance signals in the two conditions. 4896111 METHOD AND SYSTEM FOR IMPROVING RESOLUTION OF IMAGES IN MAGNETIC...

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VI

New

quire alternately magnetic resonance signals in the two conditions.

4896111 METHOD AND SYSTEM FOR IMPROVING RESOLUTION OF IMAGES IN MAGNETIC RESONANCE IMAGING

Patents

A bridge conductors for the turns of an MRI RF coil may be connected serially within a connector joint area of an inductive coil so as to selectively increase its physical size (e.g., so as to accommodate larger patient volumes to imaged therewithin). Serial capacitance may be included in at least one of the bridging conductors so as to substantially reduce the net inductive impedance of the added bridge conductors such that the standard coil RF tuning and impedance matching circuits may still operate within their normal predetermined adjustable ranges.

Yoshio Machida, Kyojiro Nanbu, Tochigi, Japan assigned to Kabushiki Kaisha Toshiba In the magnetic resonance imaging, magnetic resonance (MR) signals generated from a predetermined region of a subject are detected by using the selective excitation method. The estimation of the subject is performed by executing the repetition solution in accordance with the spectral data of detected MR signal and region data representing the region of the subject. The MR image having the high resolution than the conventional MR image is obtained.

4896113 USE OF REPEATED GRADIENT ECHOES FOR NOISE REDUCTION AND IMPROVED NMR IMAGING Norbert J Pelt assigned to General Company

Electric

A pulse sequence of an NMR system is disclosed which produces two spin echo signals which may be acquired. In addition, one or more gradient ethos are produced and acquired. The gradient echo data is combined with the spin echo data to improve signal to noise ratio, provide T2’ mapping, reduce motion induced artifacts, measure and correct for RF pulse imperfections, and to provide improved T2 measurement.

4897604 METHOD AND APPARATUS FOR SELECTIVE ADJUSTMENT OF RF COIL SIZE FOR MAGNETIC RESONANCE IMAGING Joseph W Carlson, Leon Kaufman, Peter A Rothschild assigned to The Regents of the University of California

4899109 METHOD AND APPARATUS FOR AUTOMATED MAGNETIC FIELD SHIMMING IN MAGNETIC RESONANCE SPECTROSCOPIC IMAGING James S Tropp, Kevin A Derby, K Christine Hawryszko assigned to Diasonics Inc An automated magnetic field shimming process for magnetic resonance spectroscopic imaging (MRSI) uses doubly phase encoded NMR spin echo responses in conjunction with multiple fourier transformation to derive a spectroscopic plot for each voxel in a three-dimensional array of voxels in an image volume (including portions of a living subject) which is to be subsequently subjected to MRSI using NMR FID or spin echo responses. The thus derived hydrogen peak frequency is taken as a measurement of existing static magnetic field intensity within that voxel and adjusted shim coil currents are calculated so as to reduce or minimize nonuniformity of the static magnetic field. A nonexistent pseudo shim coil having an assumed uniform shim contribution may enhance the resulting field homogeneity. The auto shimming procedure may be applied iteratively as required to achieve the predetermined degree of field uniformity.

4899110 MAGNETIC RESONANCE IMAGING APPARATUS WITH STABILIZED MAGNETIC FIELD Hiroshi Furukawa, Otawara, Japan assigned to Kabushiki Kaisha Toshiba In a magnetic resonance having a superconducting

imaging apparatus magnet to form a