Patent classifications
G01R33/56308
Data driven methods for deriving amplitude-based motion characterizations in pet imaging
Various systems and methods for generating images are provided. In some embodiments, the techniques can include acquiring a medical image and an associated motion characterization. The motion characterization can then be used to generate a plurality of gated image data sets, sorted by phase in the motion cycle. A new amplitude-based motion characterization curve is derived from the association of phases with amplitude-based characteristics in the phase gated images. This newly derived amplitude-based motion characterization curve can then be used to re-sort data according to amplitude-based gating techniques known in the field or with data driven optimization techniques.
ARTERIAL SPIN LABELING WITH EVALUATION OF INVERSION STATE OF MAGNETIZATION
An MRI system and method for generating MR images is provided. An MR signals acquisition unit is configured to generate a main magnetic field, orienting the magnetization of blood within a subject, and first inversion/non-inversion RF pulses such that predetermined sequences of blood boli with inverted/non-inverted magnetization are generated. First inversion/non-inversion MR signals can be acquired, which are caused by the influence on the magnetization by the first inversion/non-inversion RF pulses. MR images may be generated by an image generation unit based on imaging MR signals, acquired after the sequences of inverted and non-inverted blood boli have been flowed from the first region to the part to be imaged, and the predetermined sequences. An evaluation unit is configured to evaluate the inverting of the magnetization in the first region based on the first inversion and/or non-inversion MR signals. In one embodiment, the labeling efficiency of a pseudo continuous arterial spin labeling (pCASL) MRI experiment is performed.
SYSTEMS AND METHODS OF RECONSTRUCTING MAGNETIC RESONANCE IMAGES USING DEEP LEARNING
A computer-implemented method of reconstructing magnetic resonance (MR) images of a subject is provided. The method includes executing a neural network model for analyzing MR images, wherein the neural network model is trained with a first subset of training MR images as inputs and a second subset of the training MR images as outputs, wherein each image in the first subset is acquired during a neighboring respiratory phase of at least one of the images in the second subset. The method further includes receiving MR signals, reconstructing crude MR images based on the MR signals, analyzing the crude MR images using the neural network model, deriving clear MR images based on the analysis, wherein the clear MR images include reduced artifacts, compared to the crude MR images, and outputting the clear MR images.
Magnetic resonance imaging apparatus, image processing 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 acquire k-space data by executing a pulse sequence while performing undersampling. The processing circuitry is configured to generate an output target image by generating a folded image by applying a Fourier transform to the k-space data and further unfolding the folded image by performing a process that uses a regularization term. The processing circuitry applies a weight to the regularization term on the basis of whether or not each of the pixels in the output target image is included in an observation target region.
METHOD AND SYSTEM FOR IMPROVING MAGNETIC RESONANCE IMAGES
A method and a system automatically perform an image reconstruction of a biological object. The method includes acquiring at different time points t_i signal data for imaging the biological object and clustering a set of data in connection with the acquired signal data. The clustering includes constructing a matrix C, wherein an element C.sub.i,j of the matrix C is the value n_j of one of the data of the dataset acquired at the time point t_i, and then performing a similarity clustering based on the matrix C. At least one of the clusters is selected and determining for each of the time points t_i that are part of the cluster all acquired signal data that have been acquired within a predefined temporal threshold with respect to the considered time point t_i. The image reconstruction of the biological object is performed with the previously determined acquired signal data.
METHOD AND SYSTEM FOR CREATING A ROADMAP FOR A MEDICAL WORKFLOW
A method for creating a roadmap for a medical workflow includes providing a multidimensional image-dataset including a plurality of images of a predefined organ combined with a number of state-dimensions characterizing a movement state of a moving organ. Measured pilot tone data is provided from a continuous pilot tone signal acquisition. A coordinate is determined for each state-dimension based on the measured pilot tone data, and an image of the multidimensional image-dataset is selected based on the number of determined coordinates of each state dimension.
MR imaging using a 3D radial or spiral acquisition with soft motion gating
The invention relates to a method of MR imaging of an object (10). It is an object of the invention to enable MR imaging using a 3D radial or spiral acquisition scheme providing an enhanced image quality in the presence of motion. The method comprises the steps of: generating MR signals by subjecting the object (10) to an imaging sequence comprising RF pulses and switched magnetic field gradients; acquiring the MR signals using a 3D radial or spiral acquisition scheme with oversampling of a central portion (26) of k-space; detecting motion-induced displacements (d) and/or deformations of the object (10) during the acquisition of the MR signals and assigning each of the acquired MR signals to a motion state; reconstructing an MR image from the MR signals weighted in the central portion (26) of k-space, wherein a stronger weighting (W, 30) is applied to MR signals acquired in more frequent motion states, while a weaker weighting (W, 31, 32) is applied to MR signals acquired in less frequent motion states. Moreover, the invention relates to a MR device (1) and to a computer program for a MR device (1).
CARTESIAN SAMPLING FOR DYNAMIC MAGNETIC RESONANCE IMAGING (MRI)
A variable density Cartesian sampling method that allows retrospective adjustment of temporal resolution, providing added flexibility for real-time applications where optimal temporal resolution may not be known in advance. The methods provide for a computationally efficient sampling methods where a first step includes producing a uniformly random sampling pattern using a golden ratio on a grid, and the second step is applying a nonlinear stretching operation to create a variable density sampling pattern. Diagnostic quality images may be recovered at different temporal resolutions.
Devices, systems and methods for reducing motion artifacts during imaging of a neonate
Generally, a system for soothing a baby during imaging by an imaging device is provided. The system can include: a capsule incubator for positioning the baby within the imaging device, the capsule incubator can include: a bottom portion having an inner surface, a bed positioned on top of the inner surface for positioning the baby thereon, and one or more members coupled to the bottom portion that are positioned in a first position to open the capsule incubator and a second position to close the capsule incubator; a vibrational device including a vibrational element that extends from outside of the capsule incubator into the capsule incubator and is coupled to the bed to cause the bed to vibrate with a predetermined vibrational frequency, thus causing the baby to vibrate with the predetermined vibrational frequency.
Real-Time Methods for Magnetic Resonance Spectra Acquisition
The invention pertains to advances in real-time methods in nuclear magnetic resonance by offering a new dual-frequency dynamic nuclear polarization (DNP) method that uses a microwave beam to polarize the spins of electrons and concomitantly act as a NMR transmitter.