G01R33/381

MRI magnet and apparatus
11237234 · 2022-02-01 · ·

A magnet (7) for use in an apparatus (1) for performing magnetic resonance imaging (MRI) of a patient's head is an asymmetric magnet (7) comprising a plurality of coils (45, 46, 47) that are aligned along a cylindrical axis (29) to provide a magnetic field on the cylindrical axis (29). The magnet (7) has a patient end (23) arranged to be positioned adjacent or against a patient's shoulders with the patient's shoulders outside the magnet (7). The magnet has a recess (27) for receipt of the patient's head and extending into the magnet (7) from the patient end (23). The magnet (7) is configured to provide an imaging volume (35) that is positioned along the cylindrical axis (29) of the magnet (7) in the recess (27), and at least a major part of the imaging volume (35) has a substantially linear non-zero magnetic field gradient along the cylindrical axis (29).

MRI magnet and apparatus
11237234 · 2022-02-01 · ·

A magnet (7) for use in an apparatus (1) for performing magnetic resonance imaging (MRI) of a patient's head is an asymmetric magnet (7) comprising a plurality of coils (45, 46, 47) that are aligned along a cylindrical axis (29) to provide a magnetic field on the cylindrical axis (29). The magnet (7) has a patient end (23) arranged to be positioned adjacent or against a patient's shoulders with the patient's shoulders outside the magnet (7). The magnet has a recess (27) for receipt of the patient's head and extending into the magnet (7) from the patient end (23). The magnet (7) is configured to provide an imaging volume (35) that is positioned along the cylindrical axis (29) of the magnet (7) in the recess (27), and at least a major part of the imaging volume (35) has a substantially linear non-zero magnetic field gradient along the cylindrical axis (29).

LOW FIELD MAGNETIC RESONANCE IMAGING METHODS AND APPARATUS

According to some aspects, a laminate panel is provided. The laminate panel comprises at least one laminate layer including at least one non-conductive layer and at least one conductive layer patterned to form at least a portion of a B.sub.0 coil configured to contribute to a B.sub.0 field suitable for use in low-field magnetic resonance imaging (MRI).

LOW FIELD MAGNETIC RESONANCE IMAGING METHODS AND APPARATUS

According to some aspects, a laminate panel is provided. The laminate panel comprises at least one laminate layer including at least one non-conductive layer and at least one conductive layer patterned to form at least a portion of a B.sub.0 coil configured to contribute to a B.sub.0 field suitable for use in low-field magnetic resonance imaging (MRI).

MRI APPARATUS

In one embodiment, an MRI apparatus includes: a current-driven magnet configured to generate a magnetic field that predominantly determine a magnetic resonance frequency; a detector configured to detect a position of an object to be imaged in a movable state in the magnetic field; and control circuitry configured to set an imaging region of the object depending on a motion of the object by controlling a drive current of the current-driven magnet based on the detected position of the object.

Resistive electromagnet systems and methods

A magnetic resonance imaging (MRI) system having a resistive, solenoidal electromagnet for whole-body MRI may include ferromagnetic material within an envelope of the electromagnet. The system can be configured to have a field strength of at least 0.05 Tesla and its main electromagnetic field can be generated by layers of conductors instead of bundles. Certain electromagnet designs may be fabricated using non-metallic formers, such as fiberglass, and can be constructed to form a rigid object with the layers of conductors by fixing all together with an epoxy. The electromagnet may be configured to have two separated halves, which may be held apart by a fixation structure such as carbon fiber. The power supply for certain electromagnets herein may have current fluctuations, at frequencies of 180 Hz or above, of at least one part per ten thousand without requiring an additional current filter.

Resistive electromagnet systems and methods

A magnetic resonance imaging (MRI) system having a resistive, solenoidal electromagnet for whole-body MRI may include ferromagnetic material within an envelope of the electromagnet. The system can be configured to have a field strength of at least 0.05 Tesla and its main electromagnetic field can be generated by layers of conductors instead of bundles. Certain electromagnet designs may be fabricated using non-metallic formers, such as fiberglass, and can be constructed to form a rigid object with the layers of conductors by fixing all together with an epoxy. The electromagnet may be configured to have two separated halves, which may be held apart by a fixation structure such as carbon fiber. The power supply for certain electromagnets herein may have current fluctuations, at frequencies of 180 Hz or above, of at least one part per ten thousand without requiring an additional current filter.

Electron paramagnetic resonance (EPR) systems and methods for flow assurance and logging

An Electron Paramagnetic resonance (EPR) system and method allows the measurement paramagnetic characteristics of materials in real-time, such as heavy oil, hydrocarbons, asphaltenes, heptane, vanadium, resins, drilling fluid, mud, wax deposits or the like. The EPR systems and methods discussed herein are low cost, small and light weight, making them usable in flow-assurance or logging applications. The EPR sensor is capable of measuring paramagnetic properties of materials from a distance of several inches. In some embodiments, a window will be used to separate the EPR sensor from the materials in a pipeline or wellbore. Since the sensor does need to be in direct contact with the materials, it can operate at a lower temperature or pressure. In other embodiments, the EPR sensor may be placed in the materials.

Operating an MRI apparatus

A method of operating a magnetic resonance imaging (MRI) apparatus includes exciting a body coil of the MRI apparatus to emit a radio-frequency signal, determining a center frequency of a resonance curve of the body coil, and calculating a magnet target frequency based on the determined center frequency. A magnet is ramped to the magnet target frequency.

THERAPEUTIC APPARATUS

A therapeutic apparatus may be provided. The therapeutic apparatus may include a magnetic resonance imaging (MRI) device configured to acquire MRI data with respect to a region of interest (ROI) and a radiation therapy device configured to apply therapeutic radiation to at least one portion of the ROI. The MRI device may include an annular cryostat having one or more chambers, an annular structure assembly and a recess disposed on the annular structure arrangement. The radiation therapy device may at least include an accelerator and one or more collimation components.