Patent classifications
G01R33/54
Multi-state magnetic resonance fingerprinting
The invention provides for a magnetic resonance imaging system (100) for acquiring magnetic resonance data (142) from a subject (118) within a measurement zone (108). The magnetic resonance imaging system (100) comprises: a processor (130) for controlling the magnetic resonance imaging system (100) and a memory (136) storing machine executable instructions (150, 152, 154), pulse sequence commands (140) and a dictionary (144). The pulse sequence commands (140) are configured for controlling the magnetic resonance imaging system (100) to acquire the magnetic resonance data (142) of multiple steady state free precession (SSFP) states per repetition time. The pulse sequence commands (140) are further configured for controlling the magnetic resonance imaging system (100) to acquire the magnetic resonance data (142) of the multiple steady state free precession (SSFP) states according to a magnetic resonance fingerprinting protocol. The dictionary (144) comprises a plurality of tissue parameter sets. Each tissue parameter set is assigned with signal evolution data pre-calculated for multiple SSFP states.
Magnetic resonance imaging apparatus and magnetic resonance imaging method
A magnetic resonance imaging apparatus according to an embodiment includes sequence controlling circuitry and processing circuitry. The sequence controlling circuitry is configured to execute (i) a first pulse sequence in which a spatially selective Inversion recovery (IR) pulse and a spatially non-selective IR pulse are applied, and subsequently an acquisition is performed and (ii) a second pulse sequence in which the spatially non-selective IR pulse is applied without applying the spatially selective IR pulse, and subsequently an acquisition is performed, while varying the first TI period, with respect to a plurality of first TI periods. The processing circuitry is configured to calculate a second TI period to be used in a third pulse sequence and a fourth pulse sequence, based on data obtained from the first pulse sequence and the second pulse sequence. The sequence controlling circuitry executes (iii) the third pulse sequence in which the spatially selective IR pulse and the spatially non-selective IR pulse are applied, and subsequently an acquisition is performed and (iv) the fourth pulse sequence in which the spatially non-selective IR pulse is applied without applying the spatially selective IR pulse, and subsequently an acquisition is performed. The processing circuitry generates a magnetic resonance image of an imaged region based on data obtained from the third pulse sequence and the fourth pulse sequence.
Monitoring method and device for magnetic resonance imaging system and magnetic resonance imaging system
A monitoring method and device for a magnetic resonance imaging system comprises: acquiring a whole body specific absorption rate of a subject under examination; acquiring a ratio between a local region specific absorption rate and the whole body specific absorption rate of the subject under examination on the basis of current parameter information of a local coupling coil in the magnetic resonance imaging system; and calculating the local region specific absorption rate of the subject under examination on the basis of the ratio between the local region specific absorption rate and the whole body specific absorption rate, and the whole body specific absorption rate.
Method for providing a proposal for setting scan parameters and a computing unit for providing a setting aid
A proposal is provided for setting scan parameters comprising at least one value range scan parameter and at least two state scan parameters of a scan sequence of a magnetic resonance protocol for a magnetic resonance examination. A user is supported in the selection of the state scan parameters to be set by a computing unit that checks whether the selection of state scan parameters to be set made by the user comprises a permissible combination of settings and/or states. If an impermissible combination of settings and/or states is present, the computing unit ascertains at least one proposal with a permissible combination of settings and/or states for the state scan parameters to be set.
Magnetic resonance tomography system with interference reduction
To operate a magnetic resonance tomography system, first analysis signals are received by a main receive antenna and an auxiliary receive antenna. Based thereon, a first interference source and first weighting factors are determined. Second analysis signals are received by the main receive antenna and the auxiliary receive antenna and in accordance with the first weighting factors, a combination of the second analysis signals is created. Based thereon, a second interference source is determined. Second weighting factors are determined in order to suppress the influence of the first interference source and an influence of the second interference source. A magnetic resonance signal is received during an examination phase by the main receive antenna and an interference signal by the auxiliary receive antenna. An interference-suppressed magnetic resonance signal is created as a combination of the magnetic resonance signal and the interference signals depending on the second weighting factors.
MAGNETIC RESONANCE IMAGING APPARATUS AND IMAGING-TIME SHORTENING METHOD
A magnetic resonance imaging apparatus includes sequence control circuitry and processing circuitry. In CEST imaging the sequence control circuitry performs a first sequence and a second sequence under different saturation pulse conditions. The first sequence is for acquiring first magnetic resonance signals corresponding to a first frequency region of a k-space and second magnetic resonance signals corresponding to a second frequency region of the k-space. The second sequence is for acquiring third magnetic resonance signals corresponding to at least the first frequency region. The processing circuitry assigns the third magnetic resonance signals and the second magnetic resonance signals to a single k-space generated for the second sequence. Frequency including the first frequency region is lower than frequency including the second frequency region.
Method and Apparatus for Measuring Brain Free Water Content and MRI System
In a method for measuring brain free water content, in response to an RF excitation field generated on the basis of a magnetic resonance fingerprinting sequence and applied to the brain, an equilibrium magnetization mixed term (M0) signal is acquired from radiation emitted by each excited voxel of the brain, to obtain an M0 value of each voxel of the brain; a receive coil sensitivity (RP) value of each voxel of the brain is acquired; the M0 value of each voxel of the brain is divided by the RP value of the corresponding voxel to obtain a proton density (PD) value of each voxel of the brain; a PD value of cerebrospinal fluid is taken to be a reference PD value; and the PD value of each voxel of the brain is divided by the reference PD value to obtain the free water content of each voxel of the brain. The method advantageously increases the speed and accuracy of measurement of brain free water content.
Systems and methods for magnetic resonance imaging of infants
According to some aspects, a system configured to facilitate imaging an infant using a magnetic resonance imaging (MRI) device is provided herein. The system comprises an infant-carrying apparatus comprising an infant support configured to support the infant and an isolette for positioning the infant relative to the MRI device, the isolette comprising: a base for supporting the infant-carrying apparatus; and a bottom surface configured to be coupled to the MRI device. In some embodiments, the infant-carrying apparatus further comprises at least one radio frequency (RF) coil coupled to the infant support and configured to be coupled to the MRI device to detect MR signals during imaging performed by the MRI device. A method for positioning an infant relative to an MRI device using an infant-carrying apparatus and isolette is further provided herein.
Systems and methods for magnetic resonance imaging of infants
According to some aspects, a system configured to facilitate imaging an infant using a magnetic resonance imaging (MRI) device is provided herein. The system comprises an infant-carrying apparatus comprising an infant support configured to support the infant and an isolette for positioning the infant relative to the MRI device, the isolette comprising: a base for supporting the infant-carrying apparatus; and a bottom surface configured to be coupled to the MRI device. In some embodiments, the infant-carrying apparatus further comprises at least one radio frequency (RF) coil coupled to the infant support and configured to be coupled to the MRI device to detect MR signals during imaging performed by the MRI device. A method for positioning an infant relative to an MRI device using an infant-carrying apparatus and isolette is further provided herein.
Systems and methods for reconstruction of dynamic resonance imaging data
Systems and methods are provided for performing automated reconstruction of a dynamic MRI dataset that is acquired without a fixed temporal resolution. On one or more image quality metrics (IQMs) are obtained by processing a subset of the acquired dataset. In one example implementation, at each stage of an iterative process, one or more IQMs of the image subset is computed, and the parameters controlling the reconstruction and/or the strategy for data combination are adjusted to provide an improved or optimal image reconstruction. Once the IQM of the image subset satisfies acceptance criteria based on an estimate of the overall temporal fidelity of the reconstruction, the full reconstruction can be performed, and the estimate of the overall temporal fidelity can be reported based on the IQM at the final iteration.