A magnetic resonance imaging (MRI) apparatus is disclosed. The MRI apparatus includes a plurality of magnetic elements affixed in a Halbach dome structure. The Halbach dome structure defines an access aperture configured to allow access to the patient's head to enable neural intervention and defines a patient opening configured to receive a patient's head. In various aspects, the Halbach dome comprises a plurality of access apertures and/or gaps that may be adjustable in size.

An apparatus and method are provided for pelvic imaging using a saddle shaped magnetic resonance imaging system. The apparatus includes an array of electropermanent magnets having a longitudinal length that is longer than a width so that the subject may straddle the length of the array and sit on it

Interventional localization guides and methods for MRI guided pelvic interventions are disclosed. The interventional localization guides can include a stereotactic perineum positioning device having integrated MR receive coil array and fiducial receive array. The interventional localization guide can also include a physical template for guiding a surgical device, such as a biopsy needle. In various instances, the MRI guided pelvic interventions including co-registering biopsy locations on third party MRI scans.

A device for NMR spectroscopy includes a magnet arrangement, configured to produce a magnetic probe field within a magnet field of view external to the magnet arrangement. In a embodiment, the device includes a coil arrangement, configured to generate an electromagnetic excitation field within a coil field of view and a controller, configured to control the coil arrangement. The device includes a magnet adjustment arrangement, configured and arranged to modify at least one parameter of the magnet arrangement to change a spatial position of the magnet field of view.

A single-sided gradient coil set for single-sided magnetic resonance imaging system is disclosed. The coil set is configured to generate a magnetic field outwards away from the coil set. The coil set includes one or more first spiral coils at a first position relative to the aperture and one or more second spiral coils at a second position relative to the aperture. The coil set is configure to flow a current through the one or more first spiral coils and the one or more second spiral coils to generate an electromagnetic field gradient configured to project away from the coil set and into an imaging region of the magnetic imaging system.

A magnetic resonance apparatus, for acquiring magnetic resonance data from a person who is asleep, includes a person support apparatus to provide a sleeping place; an acquisition arrangement including a radiofrequency coil arrangement for transmitting excitation pulses and for receiving magnetic resonance signals; and a controller, designed to operate the acquisition arrangement according to a magnetic resonance sequence for acquiring a magnetic resonance dataset from a region under examination of the person. The magnetic resonance apparatus includes a main magnetic field of strength less than 20 mT, in particular less than 10 mT, and the controller includes an acquisition unit for acquiring a magnetic resonance dataset via a prolonged magnetic resonance sequence having a total acquisition duration of more than one hour.

A method for measuring a gradient field of a nuclear magnetic resonance (NMR) system based on a diffusion effect uses a non-uniform field magnet, an NMR spectrometer, a radio frequency (RF) power amplifier, an RF coil, and a standard quantitative phantom with known apparent diffusion coefficient (ADC) and time constant for decay of transverse magnetization after RF-pulse (T2). A plurality of sets of signals are acquired by an NMR sequence with different diffusion-sensitive gradient durations or different echo spacings and the magnitude of the gradient field is calculated by fitting based on the plurality of sets of signals. The method does not require an additional dedicated magnetic field detection device, has a short measurement time, is easy to use with the NMR system, and is convenient to complete gradient field measurement at the installation site, thereby improving the installation and service efficiency of the NMR system.

A magnet assembly for a portable magnetic resonance imaging (MRI) system includes a former having a plurality of slots and a plurality of magnet blocks configured to create a single-sided permanent magnet. Each of the plurality of magnet blocks are positioned in one of the plurality of slots of the former. The arrangement of the plurality of magnet blocks is configured to optimize homogeneity over a target field of view for brain imaging and to form a cap-shaped configuration to be positioned on a head of a subject.

A nuclear magnetic resonance (NMR) system-based substance measurement method, including: acquiring several echo signals of an NMR pulse sequence varying in echo spacing from a substance to be measured followed by processing to obtain several signals varying in transverse relaxation and diffusion attenuation; and fitting, in combination with the prior knowledge, the signals to obtain the diffusion coefficient, transverse relaxation time or/and content weight of individual components of the substance to be measured. This application further provides a substance measurement system including a console, a magnet module, and an NMR system.

A method for performing magnetic resonance imaging is provided. The method includes providing a magnetic resonance imaging system comprising: a radio frequency receive system comprising a radio frequency receive coil, and a housing, wherein the housing comprises a permanent magnet for providing an inhomogeneous permanent gradient field, a radio frequency transmit system, and a single-sided gradient coil set. The method also includes placing the receive coil proximate a target subject; applying a sequence of chirped pulses via the transmit system; applying a multi-slice excitation along the inhomogeneous permanent gradient field; applying a plurality of gradient pulses via the gradient coil set orthogonal to the inhomogeneous permanent gradient field; acquiring a signal of the target subject via the receive system, wherein the signal comprises at least two chirped pulses; and forming a magnetic resonance image of the target subject.