A magnetic resonance imaging protocol includes an acquisition segment to control an acquisition sequence to acquire magnetic resonance signals at a lower main magnetic field strength. A reconstruction segment controls reconstruction of a diagnostic magnetic resonance image from the magnetic resonance signals at a lower main magnetic field strength. A segmentation segment to control segmentation of a pre-determined image-detail of the diagnostic magnetic resonance image. In the magnetic resonance imaging protocol: the acquisition sequence has a set of imaging parameters that cause the image quality of the diagnostic magnetic resonance to be similar to the image quality of the magnetic resonance training images. The segmentation segment comprises: an initialisation portion which controls (i) access to a set of magnetic resonance training images acquired at main magnetic field of a higher main magnetic field strength (ii) registration of the diagnostic magnetic resonance image to one or more of the magnetic resonance training images and (iii) a segmentation proper applied to the diagnostic image to segment the pre-determined detail from the registered diagnostic magnetic resonance image. The one or more magnetic resonance training images includes an image detail corresponding to the pre-determined image detail in the diagnostic magnetic resonance image. Notably, the magnetic resonance training magnetic resonance images are acquired at a high magnetic field strength at 7 T and its level of detail facilitates the accurate segmentation of notably the hippocampus from diagnostic magnetic resonance images at lower field strength of 3 T. The diagnostic magnetic resonance images are acquired such that they resemble the training magnetic resonance images.

An exemplary integrated nuclear quadrupole resonance-based detection system comprises a front-end device having a hand-held form factor, wherein the front-end device is configured to scan a sample in or near a sample coil using inbuild electronics and acquire a nuclear quadrupole resonance measurement. The system further includes a swappable sample coil that is attached to an opening at a face of the front-end device and is tuned to a resonant frequency of the sample; and a swappable impedance matching network that is attached to the opening at the face of the front-end device and is configured to tune the resonant frequency of the sample coil. The inbuild electronics comprises a wireless transfer module that is configured to communicate the acquired nuclear quadrupole resonance measurement with a back-end device of the integrated nuclear quadrupole resonance-based detection system. Other systems and methods are also provided.

A method for determining a position of a mobile device relative to a B0 field magnet along a z-coordinate axis, and a device and a magnetic resonance tomography unit for performing the method are provided. The device includes a magnetic field strength sensor arranged in a fixed relative position. A characteristic magnetic field strength B.sub.ref of the B0 field magnet that emerges for a plurality of x-y coordinate pairs with a same reference z-coordinate z.sub.ref is ascertained. The device is moved along the z-coordinate axis until the magnetic field strength sensor measures the characteristic magnetic field strength B.sub.ref.

In a method and apparatus for recording a magnetic resonance dataset of a volume of interest of an object, at least one gradient moment is calculated as a function of at least one jump in susceptibility that is present in the volume of interest, between two sections of the volume of interest. An excitation pulse is radiated and at least one compensation moment is activated in a part volume of the volume of interest, for the at least partial compensation of a gradient moment caused by the jump in susceptibility. The signal generated by the excitation pulse is read out.

A method for determining a pulse duration T.sub.90 of a 90° pulse in a nuclear magnetic measuring method. A signal generator has a known generator resistance R.sub.S, wherein a coil has a coil impedance Z.sub.L with a coil resistance R.sub.L and a coil reactance X.sub.L, wherein a coupling circuit has an adjustable matching capacitance C.sub.M and an adjustable tuning capacitance C.sub.T, and wherein the medium has a Larmor precession having an angular Larmor frequency ω.sub.P. The time needed for determining the pulse duration T.sub.90 of the 90° pulse is reduced by the matching capacitance C.sub.M and the tuning capacitance C.sub.T being set so that the angular resonance frequency ω.sub.0 corresponds to the angular Larmor frequency ω.sub.P and by power matching being present between the signal generator and the coil. The coil resistance R.sub.L is determined and the pulse duration T.sub.90 is determined as a function of the coil resistance R.sub.L.

In a method and magnetic resonance (MR) apparatus for performing an adjustment of the MR system, an examination object under is divided into at least one excitation volume. First adjustment parameters for the at least one excitation volume of the object, and second adjustment parameters for the at least one excitation volume of the object, which differ from the first adjustment parameters are determined. First MR signals are acquired from the at least one excitation volume using the first adjustment parameters. Second MR signals are acquired from an excitation volume using the second adjustment parameters. A first MR image of the at least one excitation volume is reconstructed using the first MR signal. A second MR image of the at least one excitation volume is reconstructed using the second MR signal.

In a method and magnetic resonance apparatus for determining a B1 field map in a scanner of the apparatus, the B1 field map describing a local field distribution of a B1 field resulting from excitation pulses radiated in a measurement sequence, first and second measured values are acquired from a region in which nuclear spins are excited by an excitation pulse having an assigned flip angle, and a provisional flip angle is determined from the first and second measured values. A correction factor, dependent on the pulse shape of a selected excitation pulse, is then determined, and the provisional flip angle is multiplied thereby to obtain a corrected value for entry into said B1 field map.

A system may measure a response associated with a sample to an excitation. The system may compute, using the measured response and the excitation as inputs to an inverse model or a predetermined predictive model, model parameters on a voxel-by-voxel basis in a forward model with multiple voxels that represent the sample. The predetermined predictive model was trained using training data for different excitation strengths, different measurement conditions, or both. The forward model may simulate response physics occurring within the sample to a given excitation, and the model parameters may include magnetic susceptibilities of the multiple voxels. Moreover, the system may determine an accuracy of the model parameters by comparing at least the measured response and a calculated predicted value of the response using the forward model, the model parameters and the excitation. When the accuracy exceeds a predefined value, the system may provide the model parameters as an output.

This invention features systems and methods for the detection of analytes, and their use in the treatment and diagnosis of disease.

Systems and methods for reconstructing MR parameter maps of a subject from magnetic resonance fingerprinting (MRF) data acquired using a magnetic resonance imaging (MRI) system. The method includes providing MRF data acquired from a subject using an MRI system and reconstructing the MRF data by solving a constrained optimization problem using a low-rank model, for which an input to the optimization problem is the MRF data and an output from the optimization problem is the MRF time-series images.