G01R33/4616

SYSTEM AND METHOD FOR MAGNETIC RESONANCE IMAGE ACQUISITION

A system and method of acquiring an image at a magnetic resonance imaging (MRI) system is provided. Accordingly, an analog signal based on a pulse sequence and a first gain is obtained. The analog signal is converted into a digitized signal. A potential quantization error is detected in the digitized signal based on a boundary. When the detection is affirmative, a replacement analog signal based on the pulse sequence is received. At least one portion of the replacement analog signal can be based on an adjusted gain. The adjusted gain is a factor of the first gain. The replacement analog signal is digitized into a replacement digitized signal. At least one portion of the replacement digitized signal corresponding to the at least one portion of the replacement analog signal is adjusted based on a reversal of the factor.

Radio frequency coil for magnetic resonance imaging and magnetic resonance imaging system

In a radio frequency (RF) coil for a magnetic resonance imaging (MRI) system, the RF coil includes loops that are radially arranged. At least some areas of each of the loops overlap each other at a central portion of a radial structure formed by the loops.

SYSTEMS AND METHODS FOR RADIO FREQUENCY (RF) BASED SPATIAL ENCODING IN MAGNETIC RESONANCE IMAGING USING FREQUENCY-MODULATED RF PULSES
20240219496 · 2024-07-04 ·

Radio frequency (RF) gradient based magnetic resonance imaging (MRI) is provided by establishing a gradient in the RF transmit (B1) field using frequency-modulated RF pulses. A difference between the time-bandwidth product of the frequency-modulated RF pulses can be varied to provide impart different phases to magnetic resonance signals, where these different phases provide phase encoding of the acquired data. The time-bandwidth product difference can be created and varied by changing the pulse duration of one frequency-modulated RF pulse relative to the other while keeping the bandwidth of the pulses constant.

Method of magnetic resonance with excitation by a prewinding pulse

A method of magnetic resonance, in which a sample introduced in a measurement volume in an external magnetic field is excited by an excitation pulse and the signal formed by the transverse magnetization thus produced is read out by a receiving coil. The method is characterized in that a prewinding pulse is used as the excitation pulse, which prewinding pulse is characterized in that the formed transverse magnetization M.sub.() of spins of different Larmor frequency after the pulse has a phase .sub.0(), wherein .sub.0() as a function of within a predefined frequency range has an approximately linear course having negative slope, such that the spins refocus after an echo time defined by the pulse without an additional refocusing pulse being necessary.

Nuclear magnetic resonance logging tool with quadrature coil configuration

Nuclear magnetic resonance (NMR) logging tools may be configured for situation-dependent NMR logging operations by including two dissimilar coils that may function in four different modes of operation based on logging conditions including: a resistivity of the fluid, a diameter of the wellbore, a depth into the subterranean formation of the volume of investigation, or a combination thereof. For example, an NMR logging tool with a z-coil and a transversal coil may be useful in generating in a volume of investigation of a subterranean formation either (1) a transversal radiofrequency (RF) excitation with the transversal coil or (2) a quadrature RF excitation with both the z-coil and the transversal coil, where the choice of transversal or quadrature RF excitation is based on the logging conditions; and detecting an NMR signal from the subterranean formation with one of: (1) the transversal coil or (2) both the z-coil and the transversal coil.

Methods for producing a semi-adiabatic spectral-spatial spectroscopic imaging sequence and devices thereof

A method, magnetic resonance imaging computing device, and a non-transitory computer readable medium for producing a semi-adiabatic spectral-spatial spectroscopic imaging sequence for magnetic resonance imaging. A pulse control signal comprising a pair of adiabatic pulses and a linear phase pulse is generated. The pulse control signal is transformed into a pair of spectral-spatial refocusing pulses and an excitation pulse. The pair of spectral-spatial refocusing pulses and the excitation pulse are output to a waveform generator to produce the semi-adiabatic spectral-spatial spectroscopic imaging sequence.

Method and system for detection of a material within a region of the earth

Methods and systems for detecting a material within a region of the Earth are provided. The region may be under a surface of earthen formation, ice, snow, or water. The method may be practiced in a variety of applications, for example in an arctic region to detect oil spills, leaks, or seepages. The methods and systems may include using at least one coil to transmit a radio frequency (RF) excitation signal into the region of the Earth; and receive any NMR response signals to determine the presence of the material of interest.

System and method for magnetic resonance image acquisition

A system and method of acquiring an image at a magnetic resonance imaging (MRI) system is provided. Accordingly, an analog signal based on a pulse sequence and a first gain is obtained. The analog signal is converted into a digitized signal. A potential quantization error is detected in the digitized signal based on a boundary. When the detection is affirmative, a replacement analog signal based on the pulse sequence is received. At least one portion of the replacement analog signal can be based on an adjusted gain. The adjusted gain is a factor of the first gain. The replacement analog signal is digitized into a replacement digitized signal. At least one portion of the replacement digitized signal corresponding to the at least one portion of the replacement analog signal is adjusted based on a reversal of the factor.

Magnetic coupling high resolution nuclear magnetic resolution probe and method of use
10241063 · 2019-03-26 · ·

In an embodiment of the invention inductive coupling of an idler coil to a parent coil is used to provide a double resonance circuit without the disadvantages of capacitive coupling to the parent coil. In an embodiment of the invention, an inductive coupling coil can be used to achieve a double-tuned circuit. In an embodiment of the invention, a circuit uses inductive coupling to achieve a double resonance circuit for .sup.1H, .sup.19F, and .sup.13C experiments where one of the three nuclei are observed and the other two are decoupled. In an embodiment of the invention a pivot or a shunt can be used to couple and decouple the idler coil and the parent coil.

CHEMICAL-SHIFT-SELECTIVE PHASE-COMPENSATED ADIABATIC 2-REFOCUSING PULSE PAIR AND SPECTRAL EDITING METHODS FOR ULTRA-HIGH-FIELD MAGNETIC RESONANCE SPECTROSCOPY
20240241199 · 2024-07-18 ·

A method for generating 2?-refocusing pulses for magnetic resonance spectroscopy (MRS), and for performing spectral editing of MRS data using differential custom bandpass editing. Acquisition may be performed using echo-planar spectroscopic imaging (EPSI), for example. The 2?-refocusing is achieved using chemical-shift-selective adiabatic 2?-refocusing pulses, without spatial-selective (e.g. slice-selective) refocusing. The spectral editing method uses two data sets with different bandpass (full and partial) editing spectra, and takes the difference of the two edited spectra. The approach lends itself to 3D spectroscopy at B.sub.0 of 7 T or higher, and permits whole brain J-coupled metabolite editing (e.g. 2HG or GABA), with greatly reduced specific absorption rate, shorter repetition time, minimal chemical-shift displacement artefacts (CDSAs), robustness to B.sub.0-inhomogeneity and indifference to B.sub.1.sup.+-inhomogeneity compared with existing spatial-selective methods, such as MEGA.