G01R33/56308

Magnetic resonance imaging apparatus, magnetic resonance imaging method, and computer program product

A magnetic resonance imaging apparatus according to an embodiment includes sequence control circuitry and processing circuitry. The sequence control circuitry performs multi-frame acquisition where FOVs (Field Of Views) of at least two acquired frames are overlapped in a first direction. Then, based on the multi-frame acquisition performed by the sequence control unit, the processing unit generates data regarding the components in the first direction of flow of a fluid.

MAGNETIC RESONANCE PROJECTION IMAGING
20170361128 · 2017-12-21 ·

Apparatus and techniques are described herein for nuclear magnetic resonance (MR) projection imaging. Such projection imaging may be used to control radiation therapy delivery to a subject, such as including receiving reference imaging information, generating a two-dimensional (2D) projection image using imaging information obtained via nuclear magnetic resonance (MR) imaging, the 2D projection image corresponding to a specified projection direction, the specified projection direction including a path traversing at least a portion of an imaging subject, determining a change between the generated 2D projection image and the reference imaging information, and controlling delivery of the radiation therapy at least in part using the determined change between the obtained 2D projection image and the reference imaging information.

IMAGING AN OBJECT SUBJECTED TO A CYCLIC MOTION

For imaging an object subject to a cyclic motion, two or more imaging repetitions are carried out. Each of the imaging repetitions includes a sequence of equally spaced imaging events, wherein each imaging event has an event number, which corresponds to a respective predefined imaging parameter. A cycle duration of the cyclic motion is determined, a number of events per cycle is determined based on the cycle duration and a shift number is determined at least in part randomly. For a first imaging repetition, a starting number is determined depending on the number of events per cycle and the shift number. The first imaging repetition is carried out, wherein the respective sequence is started with an imaging event, whose event number is given by the starting number.

MOTION TRACKING DURING NON-INVASIVE THERAPY
20170358095 · 2017-12-14 ·

During a focused-ultrasound or other non-invasive treatment procedure, the motion of the treatment target or other object(s) of interest can be tracked in real time based on (i) the comparison of treatment images against a reference library of images that have been acquired prior to treatment for the anticipated range of motion and have been processed to identify the location of the target or other object(s) therein and (ii) complementary information associated with the stage of the target motion during treatment.

Nuclear magnetic flowmeter and method for operating a nuclear magnetic flowmeter

A nuclear magnetic flowmeter (1) for determining the flow of a medium flowing through a measuring tube (2), having a magnetic field generator (3) having permanent magnets for generating a magnetic field interfusing the medium over a magnetic field section L.sub.M, having a pre-magnetization section L.sub.VM located within the magnetic field section L.sub.M and having a measuring device also located in the magnetic field section L.sub.M including a coil-shaped antenna (4) with the length L.sub.1 serving as a measuring antenna. At least one coil-shaped antenna (5) is provided in the pre-magnetization section L.sub.VM for generating a pulse or pulse sequence spoiling the magnetization of the medium in the direction of the magnetic field.

METHOD FOR OPERATING A NUCLEAR-MAGNETIC FLOWMETER AND NUCLEAR MAGNETIC FLOWMETER

A method for operating a nuclear-magnetic flowmeter in which, when determining a velocity of the medium through a measuring tube, the dependency on properties or the state of a medium is at least reduced. The method exciting a first volume of the magnetized medium flowing at a first velocity within a first measuring section to nuclear-magnetic resonances and a first signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the first volume, and then, exciting a second volume of the magnetized medium flowing at a second velocity within the first measuring section is excited to nuclear-magnetic resonances and a second signal sequence is formed characterizing the nuclear-magnetic resonances of the medium in the second volume. A quotient sequence is determined from each of the first and second signal sequences, and the first velocity and/or the second velocity is/are determined using the quotient sequence.

MRI METHOD FOR MEASURING VELOCITY PROFILES IN DRILLING MUD
20170336489 · 2017-11-23 · ·

An MRI-based method for determining a velocity profile for a fluid flowing through a pipe, said method comprising: selecting a slice through which said fluid is flowing; selecting a pulse sequence; separating said pulse sequence into a preparation part and a readout part; applying said preparation part to said slice; waiting a predetermined time Rt; and, applying said readout part to said slice.

Non-Contrast MR Angiography with Variable Slice Resolution 3D Time-of-Flight
20170330353 · 2017-11-16 ·

A method for acquiring an image volume using a magnetic resonance imaging device includes performing an acquisition process to acquire a first dataset corresponding to a first portion of an anatomical region of interest at a first slice resolution, wherein the first dataset comprises a first plurality of three-dimensional slabs or a first plurality of two-dimensional slice regions. Additionally, one or more additional acquisition processes is performed to acquire a second dataset corresponding to a second portion of the anatomical region of interest at a second slice resolution that is lower or higher than the first slice resolution, wherein the second dataset comprises a second plurality of three-dimensional slabs or a second plurality of two-dimensional slice regions. Once the datasets are acquired, a reconstruction process is applied to jointly reconstruct the first dataset and the second dataset as a single consistent volume.

Magnetic resonance imaging apparatus and magnetic resonance imaging method

An IR pulse is applied to a tag region B that is disposed at the upstream side of the ascending aorta relative to a tag region A at a timing with a second predetermined delay time TD2 (for example, 600 ms) from the application time of an IR pulse to the tag region A to thereby perform tagging. By this tagging, it is possible to suppress the MR signals derived from the substantial portions and the blood within the tag region B. Subsequently, an imaging scan is performed after a predetermined time lapse TIA (for example, 1200 ms) from the application time of the IR pulse to the tag region A or after a predetermined time lapse TIB (for example, 600 ms) from the application time of the IR pulse to the tag region B.

DIXON MR IMAGING WITH SUPPRESSION OF FLOW ARTIFACTS
20170307715 · 2017-10-26 · ·

The invention relates to a method of MR imaging of a body (10) of a patient. It is an object of the invention to provide a method that enables efficient compensation of flow artifacts, especially for MR angiography in combination with Dixon water/fat separation. The method of the invention comprises the steps of: a) generating MR echo signals at two or more echo times by subjecting the portion of the body (10) to a MR imaging sequence of RF pulses and switched magnetic field gradients, wherein the MR imaging sequence is a Dixon sequence; b) acquiring the MR echo signals; c) reconstructing one or more single-echo MR images from the MR echo signals; d) segmenting the blood vessels from the MR images; e) detecting and compensating for blood flow-induced variations of the amplitude or phase in the single-echo MR images within the blood vessel lumen, and f) separating signal contributions from water and fat spins to the compensated single-echo MR images. Moreover, the invention relates to a MR device (1) and to a computer program for a MR device (1).