Ge Medical Systems Global Technology Company, LLC

Ge Yokogawa Medical Systems, Limited

General Electric Company

Yoshikazu Ikezaki

Aki Yamazaki

Eiji Yoshitome

Marie Uno

Hidenori Kawai

A labeling area determining apparatus is provided. The labeling area determining apparatus includes a detecting device configured to detect a tilt of a head relative to a body axial direction of a subject to be imaged by an arterial spin labeling method, and a determining device configured to determine a tilt of a labeling area of spins relative to the body axial direction of the subject, based on the tilt of the head detected by the detecting device.

Labeling area determining apparatus, magnetic resonance apparatus and method for determining tilt of labeling area

An image display apparatus which displays a form image indicative of a form about an imaging area of a subject and a quantitative value image indicative of quantitative values measured with respect to characteristics of the imaging area, said image display apparatus includes a display unit which displays the form image on a display screen thereof and a specific area setting unit which sets a specific area at the form image displayed on the display screen by the display unit. When the specific area is set at the form image by the specific area setting unit, the display unit displays the quantitative value image on the display screen side by side with the form image in such a manner that the quantitative value image indicates the quantitative values measured with respect to a position corresponding to the specific area set at the imaging area.

Image display apparatus, image display method and magnetic resonance imaging apparatus

An object of the present invention is to obtain a composite image by a small computation amount and short process time in parallel imaging using three or more reception coils. By performing a scan using three or more reception coils and with reduced phase encoding steps, data of the reception coils is collected, and an image is generated from each of the data. A combination of images used for unfolding operation is selected from combinations of the images, and a composite image is obtained by operation using the selected combination of images and a square matrix of sensitivity coefficients of the corresponding reception coils.

Parallel imaging method and MRI apparatus

With the objective of reducing the number of times that RF pulse are idle-shot during an idling time upon executing an SSFP pulse sequence by a phase cycling method and thereby performing imaging efficiently, the angle of the phase of each RF pulse is changed during the idling time so as to sequentially increase every time of repetition to a phase-increased angle at the time that the RF pulses are repeatedly transmitted at a scan executed after the idling time, thereby transmitting the RF pulses.

Magnetic resonance imaging apparatus, magnetic resonance imaging method, scan apparatus, program and storage medium

The present invention provides an MR scanning method and an MRI apparatus for decreasing the artifacts while improving the signal from within the blood vessels in the parallel imaging. In the sequence for calibration data acquisition the, RF pulse of the flip angle and the slice gradient are applied, then the phase encoding pulse is applied. Thereafter the MR signal will be received while applying the read pulse with the flow compensation pulse (marked as hatch area). Using a sequence with the flow compensation added in the calibration scanning allows decreasing the artifacts caused by the blood stream. This also increased the signal from within the blood vessels, allowing improving the S/N ratio of the calibration data.

Parallel multiple coil MR scanning method and MRI apparatus with flow compensation in a calibration scan including a calibration of a coil sensitivity of each coil

In order to positively decrease the band artifact on the middle of image when the field ununiformity is relatively fair and Nex is small, the present invention provides a phase cycling method for use in SSFP pulse sequence of a gradient echo system for rolling back the phase shift of lateral magnetization developed in TR by the gradient field prior to the next RF excitation, by identifying the RF transmission phase developing the band artifact in the vicinity of zero amount of phase shift, namely the repetition of 0-0-0-0 (degrees) as unusable RF transmission phase to use a plurality of RF transmission phases other than the unusable RF transmission phase for the phase cycling.

Phase cycling method in SSFP pulse sequence and magnetic resonance imaging apparatus

A method to generate separate water and fat images includes applying a pulse sequence, which brings about no phase difference between a water signal and a fat signal, so as to acquire calibration data items that provide the distribution of sensitivities of coils, applying a pulse sequence, which uses the phase difference between a water signal and a fat signal to separate the signals from each other, so as to receive NMR signals, which are induced by a subject, in parallel with one another using I (&#x2267;2) coils, and acquiring real data items detected by the respective coils, producing a synthetic image by performing arithmetic operations on the calibration data items and the real data items detected by the respective coils so as to remove aliasing oriented in a phase encoding direction, and producing at least one of a water image and a fat image from the synthetic image.

MR image production method and MRI apparatus

For a purpose of improving homogeneity of an image obtained in a self-calibration by a parallel imaging method generally referred to as SENSE (SENSitivity Encoding), sensitivity factors S(p) are calculated using an additive image A=&#x3a3;|C| of complex images Cobtained by conducting a calibration scan of an entire FOV for phased array coils Coil_n (n=1&#x2013;N, N&#x2267;2) (Steps V, V). Moreover, sensitivity maps Sare generated by conducting curve fitting by the method of least squares weighted by the square of a pixel value A(p) of the absolute value additive image A(Step V).

Coil sensitivity map generating method, parallel imaging method, and MRI apparatus

An apparatus for removing wraparound artifacts without degrading image quality of an image includes a phase correcting section for conducting phase correction processing on received signals in an actual scan based on a reference signal as a corrective signal received by one of a plurality of receive coils, for example, by a receive coil, without applying a gradient magnetic field Gp in a phase encoding direction, and an unfolding section for removing wraparound artifacts in an image based on the signals received by the plurality of receive coils in the actual scan and subjected to the phase correction processing by the phase correcting section, and on the difference in sensitivity distribution among the plurality of receive coils, so that the phase correction processing is conducted while preserving the relative phase relationship among the coils, and unfolding processing (removal processing) is conducted using the result of such phase correction processing.

Nuclear magnetic resonance imaging apparatus and nuclear magnetic resonance imaging method

For the purpose of enabling parallel imaging even when a navigator echo is used to phase-correct an imaging echo, the present invention involves: exciting spins within a subject to acquire an imaging echo generated by the excited spins along with a navigator echo, with a reduced field-of-view via a plurality of receiver systems; conducting phase correction on the imaging echo based on the navigator echo; producing an intermediate image based on the phase-corrected imaging echo from each of the plurality of receive systems; generating a sensitivity matrix for the plurality of receiver systems; correcting the phase of matrix data in the sensitivity matrix; and producing an image with a full field-of-view based on the intermediate image and the phase-corrected sensitivity matrix.

MRI systems with parallel receivers for phase correction

To correct motion and magnetic field inhomogeneity phase errors, inverting data collecting read gradients Nr and Nr are applied to collect correcting data H (n, ) and H (n, ) corresponding to focused navigation echoes Ne and Ne data collecting read gradients r , . . . , rM which are inverted alternately are applied, and phase encode gradients pdn, p , . . . , pM are applied at inverting, thereby collecting imaging data F (n, ), . . . , F (n, M) corresponding to the focused imaging echoes e , . . . , eM. This sequence is repeated for n&equals; , . . . , N while changing the magnitude of the phase encode gradient pdn, whereby data F ( ) to F (N, M) for filling a k space are collected. Based on the correcting data H (n, ) and H (n, ), the imaging data F (n, ), . . . , F (n, M) are phase corrected.

Systems and methods for correcting phase errors

In order to reduce ghost artifacts due to a Maxwell term phase error caused by a data acquisition read gradient, an n-th Maxwell term collection pulse MTCP is appended before an inversion RF pulse RF180 for an n-th shot in an I-echo N-shot EPI pulse sequence. The n-th Maxwell term collection pulse MTCP has a waveform whose time integral value is zero, and gives a bias phase error such that a Maxwell term phase error which is caused by a data acquisition read gradient and contained in data filling out a k-space smoothly varies from a 1 row to an N&middot;I-th row in the direction of a phase encoding axis.

MRI apparatus which has reduced ghost artifacts due to Maxwell term phase error

To preventing a deterioration in NMR signals due to a slice-leaned state, in executing a pulse sequence by the spin echo method, the inclination angle G of the slice gradient at the time of applying a 180&deg; RF pulse P is made smaller than the inclination angle G of the slice gradient at the time of applying a 90&deg; RF pulse R.

MR method and apparatus for making broader the 180&deg; excitation width

A data collection method for MR angiography, wherein the scans resulting in spin warp values are assigned into groups of two or more consecutive acquisitions and each group is averaged two or more times for each heart beat period, whereby data collection time is reduced concurrently with suppression of motion artifacts, all without use of additional hardware.

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Tokyo, Japan

Yoshikazu Ikezaki