Patent classifications
G01R33/50
Method for operating a magnetic resonance apparatus, magnetic resonance apparatus, computer program and electronically readable data storage medium
In a method for operating a magnetic resonance (MR) apparatus, MR raw-data is acquired from an acquisition region of a patient for a sampling region of k-space using a MR sequence that employs ultrashort echo times; a first MR image dataset is reconstructed from the MR raw-data of the k-space region; a second MR image dataset is reconstructed from the MR raw-data in a central subregion of the sampling region in k-space; a resolution of the second MR image dataset is interpolated to increase the resolution of the second MR image dataset to a resolution of the first magnetic resonance image dataset; and the first and second MR image datasets are combined to obtain an output MR image dataset.
Magnetic resonance imaging apparatus and magnetic resonance imaging method
In MRI, upon simultaneously generating computed images of multiple parameters, imaging time is efficiently reduced while preventing decrease in spatial resolution and SN ratio as much as possible. A plurality of original images is reconstructed from nuclear magnetic resonance signals acquired under various imaging conditions, and a computed image is obtained by calculation performed among the plurality of original images. The various imaging conditions include an imaging condition that a repetition time of an imaging sequence is different from one another, and upon imaging, the number of phase encoding steps is made smaller when the repetition time is long. An image is reconstructed in such a manner that a matrix size of the image obtained when the number of phase encoding steps is small is made equal to the matrix size of the image obtained when the number of phase encoding steps is large.
Method and apparatus for T.SUB.1.-T.SUB.2.* relaxation correlation magnetic resonance measurement of materials
A T.sub.1-T.sub.2* measurement which permits speciation of different components with restricted mobility in samples where a T.sub.1-T.sub.2 measurement is impossible is disclosed. Tracking the T.sub.1-T.sub.2* coordinate, and associated signal intensity changes, can reveal additional structural and/or dynamic information such as phase changes in rigid/semi-rigid biopolymer samples or pore level changes in morphology of the water environments in cement-based materials. In another aspect, the T.sub.1-T.sub.2* measurement may also be employed to discriminate composition in solid mixtures, a very significant analytical problem in industry. In a further aspect, the T.sub.1-T.sub.2* measurement has particular value in permitting a simple assignment of T.sub.1 to different T.sub.2* populations.
Method and apparatus for T.SUB.1.-T.SUB.2.* relaxation correlation magnetic resonance measurement of materials
A T.sub.1-T.sub.2* measurement which permits speciation of different components with restricted mobility in samples where a T.sub.1-T.sub.2 measurement is impossible is disclosed. Tracking the T.sub.1-T.sub.2* coordinate, and associated signal intensity changes, can reveal additional structural and/or dynamic information such as phase changes in rigid/semi-rigid biopolymer samples or pore level changes in morphology of the water environments in cement-based materials. In another aspect, the T.sub.1-T.sub.2* measurement may also be employed to discriminate composition in solid mixtures, a very significant analytical problem in industry. In a further aspect, the T.sub.1-T.sub.2* measurement has particular value in permitting a simple assignment of T.sub.1 to different T.sub.2* populations.
Nuclear magnetic resonance measurement apparatus and method
Nuclear spins of particular atoms (14N) which distinctively exist in a crystal of an active pharmaceutical ingredient is manipulated, so that an initial magnetization (modulated magnetization) is caused in nearby hydrogen atoms which exist near the particular atoms in the crystal. The initial magnetization of the nearby hydrogen atoms is spread to peripheral hydrogen atoms which exist at a periphery of the nearby hydrogen atoms in the crystal. A magnetization which is spread in the crystal is directly or indirectly observed.
Nuclear magnetic resonance measurement apparatus and method
Nuclear spins of particular atoms (14N) which distinctively exist in a crystal of an active pharmaceutical ingredient is manipulated, so that an initial magnetization (modulated magnetization) is caused in nearby hydrogen atoms which exist near the particular atoms in the crystal. The initial magnetization of the nearby hydrogen atoms is spread to peripheral hydrogen atoms which exist at a periphery of the nearby hydrogen atoms in the crystal. A magnetization which is spread in the crystal is directly or indirectly observed.
WETTABILITY ESTIMATION USING MAGNETIC RESONANCE
A method of estimating a wettability characteristic of a rock and fluid system includes acquiring a sample of the rock material, performing a first nuclear magnetic resonance (NMR) measurement of the sample when the sample is in a full water saturation condition, and measuring a first T2 distribution, performing a second NMR measurement of the sample when the sample is in a second partial saturation condition, and measuring a second T2 distribution. The method also includes separating a hydrocarbon component of the second T2 distribution from a water component of the second T2 distribution, applying a fluid substitution model to the water component of the second T2 distribution to generate a computed T2 distribution, and calculating a wettability index (WI) based on a difference between the first T2 distribution and the computed T2 distribution.
WETTABILITY ESTIMATION USING MAGNETIC RESONANCE
A method of estimating a wettability characteristic of a rock and fluid system includes acquiring a sample of the rock material, performing a first nuclear magnetic resonance (NMR) measurement of the sample when the sample is in a full water saturation condition, and measuring a first T2 distribution, performing a second NMR measurement of the sample when the sample is in a second partial saturation condition, and measuring a second T2 distribution. The method also includes separating a hydrocarbon component of the second T2 distribution from a water component of the second T2 distribution, applying a fluid substitution model to the water component of the second T2 distribution to generate a computed T2 distribution, and calculating a wettability index (WI) based on a difference between the first T2 distribution and the computed T2 distribution.
SYSTEMS AND METHODS OF CONSTRAINED RECONSTRUCTION OF IMAGES WITH WHITE NOISE
A magnetic resonance imaging (MRI) system can include a processor and a memory. The processor can receive an acquired magnetic resonance (MR) dataset having a first signal-to-noise ratio (SNR). The processor can extract, from the acquired MR dataset, a first set of values corresponding to a first variable having a second SNR and a second set of values corresponding to a second variable. The processor can apply a constraint function that includes a function of the first variable and the second variable. The processor can minimize a cost function according to the constraint function to generate a cost function solution. The processor can input the first variable and the second variable into the cost function solution to generate a modified first variable having a third SNR, the third SNR being greater than the second SNR.
Method and apparatus for improved efficiency of non-cartesian imaging using accelerated calibration scan for k-space shift correction
A system and method for performing accelerated k-space shift correction calibration scans for non-Cartesian trajectories is provided. The method can include applying an MRI sequence, performing a calibration scan based on the MRI sequence using the non-Cartesian trajectory to acquire k-space shift data, wherein one or more partitions are skipped during the calibration scan, interpolating the skipped one or more partitions using the k-space shift data from adjacent partitions, and calibrating the MRI system using the k-space shift data and the interpolated k-space shift data. In some embodiments, an acceleration factor Acc can be defined and the calibration scan acquires k-space shift data for only one partition in every Acc partitions.