44 results about "Water proton" patented technology

A noninvasive image measuring method of measuring internal organ / tissue temperature using an MRI system. Temperature measurement insusceptible to body motion and spatial variation of magnetic field is realized by utilizing the position and size of a temperature change region as a priori information to determine the phase distribution of the complex magnetic resonance signal of water proton at a given temperature point and by subtracting the phase distribution before the temperature change estimated (self-referred) from the phase distribution in the peripheral region for each pixel of the image, thereby eliminating the subtraction process of image before and after temperature change. The precision of temperature measurement can be enhanced by estimating a complex curved surface formed of the peripheral region in each temperature change region of the real-part and imaginary-part images of the complex magnetic resonance signal, and calculating the phase difference between an actually measured complex signal distribution and the estimated complex signal distribution of the complex signal distribution for each pixel, thereby reducing the estimation error due to phase transition from −π to +π occurring in a phase distribution. Furthermore, temperature can be measured through optimal imaging following up body motion by using an optical positioning system in combination even if the part being measured is shifted.

Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and / or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and / or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

The invention relates to a method of MR imaging of at least a portion of a body of a patient placed in an examination volume of an MR device. The object of the invention is to improve CEST contrast enhanced imaging. The method of the invention comprises the following steps: a) saturation of nuclear magnetization of exchangeable protons of a CEST contrast agent administered to the patient by subjecting the portion of the body to at least one frequency-selective saturation RF pulse matched to the MR frequency of exchangeable protons of the CEST contrast agent, wherein the saturation period, i.e. the duration of the frequency-selective saturation RF pulse, is shorter than the time required for saturation to build up a full CEST contrast enhancement effect when starting from zero saturation; b) generating at least one MR signal of water protons of the body by subjecting the portion of the body to an MR imaging sequence comprising at least one RF pulse and switched magnetic field gradients; c) acquiring and sampling the at least one MR signal from the body; d) repeating steps a) to c) a number of times under variation of parameters of the MR imaging sequence, wherein MR signals are acquired and sampled during a saturation build-up period, i.e. before a steady state of the CEST effect is achieved; e) reconstructing a proton-density weighted, CEST contrast-enhanced MR image from the acquired and sampled MR signals.

The present invention relates generally to multimodal magnetic resonance imaging (MRI) contrast agents. In particular, the present invention provides a MRI contrast agent configured to manipulate both the longitudinal (T1) and transverse (T2) relaxation times of surrounding water proton spins.

For generating of magnetic resonance exposures of an examination subject, a dielectric element with high dielectric constant is positioned on the examination subject to locally influence the B1 field distribution, the dielectric element being formed primarily of material whose magnetic resonance line(s) is / are shifted by at least a specific degree relative to the magnetic resonance line of water protons for a given magnetic field. In a measurement for generation of a magnetic resonance exposure a measurement sequence is used, such in the acquisition of the raw image data the dielectric material of the dielectric element supplies no signal contributions for the image generation and / or the signals caused by the dielectric material of the dielectric element can be separated from the signals caused by the examination subject.

Charged spray droplets are guided in a pseudopotential distribution generated by audio frequency voltages at electrodes of a guiding device, focusing the spray droplets toward the axis. An axial electric field profile and an axial flow profile of a drying gas in the guiding device allow the drift of different-sized droplets to be controlled in the longitudinal direction of the guiding device, so that the droplets are roughly equal in size when they leave the guiding device and finally dry up shortly after leaving. As a result, the ions are formed in a relatively small spatial region. Electrostatic potentials guide the analyte ions from this small spatial region to the entrance aperture of the inlet capillary; during this process, very light ions, especially protons and water-proton complexes, can be filtered out by a mobility filter.

Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and / or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and / or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

The invention relates to a medicinal ultrahigh-field nuclear-magnetism contrast agent and a preparation method thereof. The medicinal ultrahigh-field nuclear-magnetism contrast agent is NaHoF4 nano-particles modified by phospholipid PEG (polyethylene glycol). A paramagnetic element Ho in NaHoF4 has the maximal effective electron magnetic moment and can be used for effectively changing transverse relaxation time of water protons to produce a T2-weighted imaging effect which is sharply increased with the increase of filed strength and can be used for clinical ultrahigh-field nuclear-magnetism contrast imaging in the future. Moreover, the phospholipid PEG is utilized to perform hydrophilic modification on NaHoF4 particles, so that the biocompatibility is increased, the toxic or side effects are lowered and the blood circulation is promoted. The preparation method is convenient to modify, efficient and beneficial to further grafting biological ligand subsequently.

For generating of magnetic resonance exposures of an examination subject, a dielectric element with high dielectric constant is positioned on the examination subject to locally influence the B1 field distribution, the dielectric element being formed primarily of material whose magnetic resonance line(s) is / are shifted by at least a specific degree relative to the magnetic resonance line of water protons for a given magnetic field. In a measurement for generation of a magnetic resonance exposure a measurement sequence is used, such in the acquisition of the raw image data the dielectric material of the dielectric element supplies no signal contributions for the image generation and / or the signals caused by the dielectric material of the dielectric element can be separated from the signals caused by the examination subject.

The present invention relates to a magnetic resonance structure with a cavity or a reserved space that provides contrast and the additional ability to frequency-shift the spectral signature of the NMR-susceptible nuclei such as water protons by a discrete and controllable characteristic frequency shift that is unique to each MRS design. The invention also relates to nearly uniform solid magnetic resonance T2* contrast agents that have a significantly higher magnetic moment compared to similarly-sized existing MRI contrast agents. The invention also relates to a magnetic resonance sensor that alters it shape in response to a condition of an environment such that the condition may be detected.

The present invention relates to a magnetic resonance structure with a cavity or a reserved space that provides contrast and the additional ability to frequency-shift the spectral signature of the NMR-susceptible nuclei such as water protons by a discrete and controllable characteristic frequency shift that is unique to each MRS design. The invention also relates to nearly uniform solid magnetic resonance T2* contrast agents that have a significantly higher magnetic moment compared to similarly-sized existing MRI contrast agents.

The invention discloses a state monitoring method for a proton exchange membrane fuel cell. The state monitoring method comprises the following steps: introducing the optimal size of a V-I characteristic curve slope k as a control index for a stable working state of the fuel cell; and generating a control signal according to information of measured k, and controlling operating conditions of the fuel cell, thereby adjusting the fuel cell to work on an ohm segment. The invention further discloses a state monitoring system for the fuel cell. The state monitoring system comprises a fuel cell stack (the optimal working temperature is 60 DEG C), a hydrogen supply pipeline system, an air supply pipeline system, a cooling water circulation system, an exhaust discharge system, an impedance testing system, a safety monitoring system and a detection control system. The V-I characteristic curve slope k of the fuel cell is obtained through the detection control system; with k as the control index, the fuel cell quickly restores to the ohm segment; the possibility of water logging and membrane dryness of a proton exchange membrane is lowered; and the performance of the fuel cell is greatly improved.

The invention relates to a method of Dixon-type MR imaging. It is an object of the invention to provide a method that enables Dixon water / fat separation with high SNR and with improved noise propagation in the water / fat separation. The method comprises the steps of: —subjecting an object (10) to a first imaging sequence, which generates a number of differently phase encoded first MR echo signals at a first echo time, such that contributions from MR signals emanating from water protons and MR signals emanating from fat protons to the first MR echo signals are essentially in phase, —acquiring the first MR echo signals using a first signal receiving bandwidth, —subjecting the object (10) to a second imaging sequence which generates a number of differently phase encoded second MR echo signals at a second echo time, such that contributions from MR signals emanating from water protons and MR signals emanating from fat protons to the second MR echo signals are at least partially out of phase, —acquiring the second MR echo signals using a second signal receiving bandwidth which is larger than the first receiving bandwidth, wherein the number of phase encodings of the first imaging sequence is smaller than the number of phase encodings of the second imaging sequence, and —reconstructing a MR image from the first and second MR echo signals, whereby signal contributions from water protons and fat protons are separated. Moreover the invention relates to a MR device and to a computer program to be run on a MR device.