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公开(公告)号：US4698595A
公开(公告)日：1987-10-06
申请号：US735006
申请日：1985-05-17
申请人： Peter Roschmann
发明人： Peter Roschmann
CPC分类号： G01R33/3628 , G01R33/28
摘要： The invention relates to a drive mechanism for adjusting an element by means of which the resonance frequency in an NMR-apparatus can be varied. The mechanism comprises a coil which is exposed to the main magnetic field off the NMR-apparatus. The coil is connected to a current-pulse supply and is deflected out of its rest position by the current pulses. The reciprocating movement of the coil is converted by a stepping mechanism into a stepwise rotary or translational movement of the adjusting element which tunes or matches the RF coil to the RF generator.
摘要翻译： 本发明涉及一种用于调节元件的驱动机构，通过该驱动机构可以改变NMR装置中的共振频率。 该机构包括从NMR装置暴露于主磁场的线圈。 线圈连接到电流脉冲电源，并通过电流脉冲偏离其静止位置。 线圈的往复运动由步进机构转换成调谐元件的逐步旋转或平移运动，该调节元件将RF线圈调谐或匹配到RF发生器。
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2.发明授权
公开(公告)号：US4682106A
公开(公告)日：1987-07-21
申请号：US714405
申请日：1985-03-21
CPC分类号： G01R33/485 , G01R33/46
摘要： A method for proton decoupling, nuclear Overhauser enhancement and/or in selective saturation magnetic resonance spectroscopy, particularly relevant to in vivo spectroscopic imaging, utilizes a radio-frequency pulse modulated with a truncated (sinc X)/X function capable of being windowed. The radio-frequency pulse is tuned to the frequency of the nuclear species, such as .sup.1 H, to be decoupled or saturated and has a bandwidth adjusted to correspond to the entire chemical shift spectrum of the nuclear species to be decoupled, minimizing the amount of radio-frequency power transmitted into a volume of the irradiated sample. Several methods, and several embodiments of apparatus, for forming the required radio-frequency pulse, are disclosed.
摘要翻译： 特别是与体内光谱成像相关的用于质子解耦，核Overhauser增强和/或选择性饱和磁共振光谱的方法利用能够被窗口化的截短（sinc X）/ X函数调制的射频脉冲。 射频脉冲被调谐到诸如1H的核物质的频率被解耦或饱和，并且具有调整的带宽以对应于待解耦的核物质的整个化学位移谱，最小化无线电量 射频功率传输到被照射样品的体积中。 公开了用于形成所需射频脉冲的几种方法和装置的若干实施例。
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公开(公告)号：US4646024A
公开(公告)日：1987-02-24
申请号：US548174
申请日：1983-11-02
CPC分类号： H01F7/20 , H01F41/045 , Y10S505/844
摘要： In the production of nuclear magnetic resonance images, it is necessary to provide various magnetic fields with specified orientations and configurations in particular relationships with respect to a cylindrical coil form on which the RF and gradient coils are generally disposed. In particular, it is necessary to produce so-called transverse gradient fields which are oriented transversely with respect to the cylindrical form. It is necessary to produce a component parallel to the axis of the cylinder, but which component varies linearly in intensity in the direction transverse to the axis. That is to say, it is desirable to produce a magnetic field component within the cylinder such that surfaces on which this component is constant are parallel and are generally oriented parallel to the axis of the cylinder. Furthermore, for the purpose of providing proper spatial definition and resolution, it is necessary that this transverse field exhibit a highly linear variation in intensity inside the cylinder. In a nuclear magnetic resonance imaging system, two such coil sets are required and are oriented at right angles to one another so as to generate x-axis and y-axis positioning information. The present invention describes coil winding patterns which are capable of producing such transverse gradient magnetic fields with an exceedingly high degree of linearity.
摘要翻译： 在生产核磁共振图像时，有必要提供具有指定取向和配置的各种磁场，这些磁场与通常设置有RF和梯度线圈的圆柱形线圈形式有关。 特别地，有必要产生相对于圆柱形横向定向的所谓的横向梯度场。 需要产生平行于圆柱体轴线的分量，但哪个分量在横向于轴线的方向上强度线性变化。 也就是说，期望在圆柱体内产生磁场分量，使得该部件恒定的表面是平行的，并且大致定向为平行于圆柱体的轴线。 此外，为了提供适当的空间定义和分辨率，有必要使该横向场在气缸内呈现高度线性的强度变化。 在核磁共振成像系统中，需要两个这样的线圈组，并且彼此成直角定向，以便产生x轴和y轴定位信息。 本发明描述了能够产生具有非常高的线性度的这种横向梯度磁场的线圈绕组图案。
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4.发明授权Correction circuit for a static magnetic field of an NMR apparatus and NMR apparatus for utilizing the same 失效用于NMR装置的静磁场的校正电路和利用其的NMR装置
公开(公告)号：US4644473A
公开(公告)日：1987-02-17
申请号：US603726
申请日：1984-04-25
IPC分类号： A61B10/00 , A61B5/055 , G01R33/24 , G01R33/385 , G01R33/389 , G01R33/565 , G01N27/00 , G01R33/08
CPC分类号： G01R33/24 , G01R33/389 , G01R33/56563
摘要： In the NMR apparatus the resonant conditions may be kept constant by adjusting the strength of the static magnetic field. The echo signal that is induced under the specific conditions is processed so as to obtain the deviation of the resonant frequency in the correction circuit. The shift of the given static magnetic field is calculated based upon the deviation of the resonant frequency. The DC energizing current for the H.sub.O power supply is varied based upon the magnetic field shift so as to maintain the NMR phenomenon at the desirable resonant conditions.
摘要翻译： 在NMR装置中，通过调整静磁场的强度，可以使谐振条件保持恒定。 处理在特定条件下感应的回波信号，以获得校正电路中的谐振频率的偏差。 基于谐振频率的偏差计算给定静态磁场的偏移。 用于HO电源的DC通电电流基于磁场偏移而变化，以将NMR现象保持在期望的谐振条件。
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公开(公告)号：US4532473A
公开(公告)日：1985-07-30
申请号：US495556
申请日：1983-05-18
申请人： Felix W. Wehrli
发明人： Felix W. Wehrli
IPC分类号： G01R33/20 , A61B5/0265 , A61B5/055 , A61B10/00 , G01F1/716 , G01N24/00 , G01P5/18 , G01P5/22 , G01R33/563 , G01R33/08
CPC分类号： G01F1/716 , G01R33/56308
摘要： A method for measuring (direction and magnitude) and imaging fluid flow in an NMR sample. Nuclei in an imaging slice, transaxial, for example, to a direction of fluid flow, are first tagged (saturated or inverted) and then excited to produce a first NMR signal. This signal originates from tagged nuclei in the imaging slice and untagged nuclei which have partially or wholly replaced nuclei flowing out of the slice. Thereafter, nuclei are tagged in a second thicker sample region which includes the imaging slice and extends therefrom in a direction opposite to the fluid flow. The nuclei are again excited in the imaging slice. The NMR signal detected is again from the entire imaging slice but is due entirely to tagged nuclei (if the second slice is selected to have the appropriate thickness) and, therefore, has a smaller magnitude than the first signal. These signals are useful in measuring the fluid flow velocity. The method is also useful, for example, with multiple-angle projection reconstruction and two-dimensional Fourier transform (2DFT) techniques to reconstruct NMR images exhibiting flowing nuclei only.
摘要翻译： 用于在NMR样品中测量（方向和幅度）和成像流体流动的方法。 成像切片中的核，例如向轴向流动流动的方向，首先被标记（饱和或反转），然后被激发以产生第一NMR信号。 该信号源自成像切片中的标记核和未部分或未完全取代流出切片的核的未标记核。 此后，核被标记在包括成像切片的第二较厚的样品区域中并且在与液体流相反的方向上从其延伸。 核在成像切片中再次被激发。 检测到的NMR信号再次来自整个成像切片，但完全归因于标记的核（如果第二切片被选择为具有适当的厚度），并且因此具有比第一信号更小的幅度。 这些信号可用于测量流体流速。 该方法也可用于例如多角度投影重建和二维傅立叶变换（2DFT）技术，以重建仅显示出流核的NMR图像。
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6.发明授权Device for generating images of an object under examination using nuclear magnetic resonance 失效用于使用核磁共振产生检查对象的图像的装置
公开(公告)号：US4528510A
公开(公告)日：1985-07-09
申请号：US522135
申请日：1983-08-11
申请人： Wilfried Loeffler , Arnulf Oppelt
发明人： Wilfried Loeffler , Arnulf Oppelt
摘要： The invention involves a device for generating images using nuclear magnetic resonance in which coils are provided for applying magnetic fields to the patient and for recording the displacement of the atomic nuclei of the patient from their equilibrium state by a high-frequency magnetic excitation pulse. Calibration devices are attached in the coils so that, for each image plane selected, they are at least partially intersected by the image plane during measurement of a patient.
摘要翻译： 本发明涉及一种用于使用核磁共振产生图像的装置，其中提供线圈以向患者施加磁场，并通过高频磁激励脉冲记录患者的原子核从其平衡状态的位移。 校准装置附接在线圈中，使得对于所选择的每个图像平面，在测量患者期间它们至少部分地与图像平面相交。
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公开(公告)号：US4520316A
公开(公告)日：1985-05-28
申请号：US488415
申请日：1983-04-25
CPC分类号： G01R33/483 , G01R33/485
摘要： A method of obtaining an NMR spectrum for at least a portion of a specimen slice is provided. The method comprises acquiring a number of projections of the specimen slice and shifting the projections by .DELTA.f for any point of interest. The shifted projections are then summed or compared to produce a resultant point spectrum. Preferably, shifted projections in each of a plurality of selected sets thereof are compared so as to produce a plurality of resultant spectra for the point which are used to produce a first iterated point spectrum. Additional stages of iteration are provided to minimize the effect of artifacts which comprises comparing aligned corresponding positions on an i iterated spectrum with a previously uncompared resultant point spectrum, so as to produce an i+1 iterated spectrum for the point, and repeating the foregoing a plurality of times, in each case using the iterated spectrum from the previous iteration as the i iterated spectrum.
摘要翻译： 提供了一种获得用于至少一部分样品片的NMR光谱的方法。 该方法包括获取样本片段的多个投影并且通过DELTA f将投影移动到任何兴趣点。 然后将移位的投影相加或比较以产生合成点谱。 优选地，将多个选定组中的每一组中的偏移投影进行比较，以产生用于产生第一迭代点光谱的点的多个合成光谱。 提供迭代的附加阶段以最小化伪像的影响，其包括将i迭代频谱上的对准的对应位置与先前未比较的结果点频谱进行比较，以便产生该点的i + 1迭代频谱，并重复前述 在每种情况下，使用来自先前迭代的迭代频谱作为迭代频谱，多次。
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公开(公告)号：US4506222A
公开(公告)日：1985-03-19
申请号：US320953
申请日：1981-11-09
申请人： William A. Edelstein , James M. S. Hutchison , Glyn Johnson , Thomas W. T. Redpath , John R. Mallard
发明人： William A. Edelstein , James M. S. Hutchison , Glyn Johnson , Thomas W. T. Redpath , John R. Mallard
CPC分类号： G01R33/482 , G01R33/5615 , G01R33/5616
摘要： To produce image information from an object it is subjected to a continuous static magnetic field along a Z axis and to sets of sequences of orthogonal gradients G.sub.x, G.sub.y and G.sub.z to the magnetic field. Spins in a selected plane (the X-Z plane) are excited by selective rf pulses and an associated G.sub.y gradient and the selected spins are subjected to all three gradients of which the G.sub.z gradient provides twist or warp to each column of spins extending along the Z axis to phase-encode the columns. The spin-echo signals are read out in the presence of a G.sub.x gradient. In each set of sequences a different value of Z gradient is employed. The Fourier transformed spin-echo signals obtained from each sequence, when arranged in order of increasing G.sub.z gradient and subjected to a second Fourier transform represent the distribution of spin density in the Z direction, thus giving a two-dimensional image of the selected X-Z plane.
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9.发明授权Method of measuring NMR spin-spin relaxation time (T.sub.2) using spin-echos 失效使用自旋回波测量NMR自旋 - 自旋弛豫时间（T2）的方法
公开(公告)号：US4502007A
公开(公告)日：1985-02-26
申请号：US462137
申请日：1983-01-31
申请人： Gary L. Mee , M. Robert Willcott
发明人： Gary L. Mee , M. Robert Willcott
摘要： A method is disclosed for measuring the NMR spin-spin relaxation time (T.sub.2) of nuclei using spin-echos comprising the steps of locating the nuclei in a static magnetic field, applying an RF pulse to the nuclei at the Larmor frequency of the nuclei of sufficient duration to rotate the net magnetic moment of the nuclei 90.degree., waiting a time period tau that is at least the time required for the free induction decay signal to go to zero, applying an RF pulse at the same Larmor frequency to the nuclei of sufficient duration to rotate the net magnetic moment of the nuclei 180.degree., recording the primary echo induced, waiting a time period equal to at least 3 tau, to cause the stimulated echos produced by the inhomogeneities in the RF magnetic field to fall into separate time zones from each other and the primary echo, applying an RF pulse at the same Larmor frequency to the nuclei of sufficient duration to rotate the net magnetic moment of the nuclei another 180.degree. to produce the primary and error stimulated echos, recording the primary and error stimulated echos induced thereby during a time period sufficient to allow the peaks of all of the error stimulated echos and the primary echos to appear in different time slots in the time zone, repeating the last three steps to obtain a series of frames each of which contain a primary echo and error stimulated echos, adding the primary echo and related error stimulated echos in each frame to obtain points on a decay curve indicating T2 relaxation time.
摘要翻译： 公开了一种用于测量使用自旋回波的核的自旋 - 自旋弛豫时间（T2）的方法，包括以下步骤：将核定位在静态磁场中，将RF脉冲以核的拉莫尔频率 足够的持续时间来旋转核的净磁矩90°，等待至少是自由感应衰减信号变为零所需时间的时间段τ，将相同拉莫尔频率的RF脉冲施加到 足够的持续时间来旋转核的净磁矩180°，记录主要回波引起的，等待至少3 tau的时间段，以使由RF磁场中的不均匀性产生的刺激回波落入分离时间 区域和主回波，将相同拉莫尔频率的RF脉冲施加到具有足够持续时间的核以将核的净磁矩旋转180°以产生主要的 记录由此引起的主要和错误刺激的回波在足以允许所有误差刺激回波的峰值和主回波出现在时区中的不同时隙中的时间段中的主要和误差刺激回波，重复最后三个步骤 以获得一系列帧，每个帧包含主回波和误差刺激回波，在每帧中添加主回波和相关误差刺激回波，以获得指示T2弛豫时间的衰减曲线上的点。
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公开(公告)号：US4477777A
公开(公告)日：1984-10-16
申请号：US389064
申请日：1982-06-16
申请人： Roy E. Gordon
发明人： Roy E. Gordon
IPC分类号： G01R33/465 , G01R33/485 , G01R33/08
CPC分类号： G01R33/465 , G01R33/485 , Y10S505/844
摘要： A method of determining or imaging fats in a non .sup.13 C enriched biological sample, particularly human tissue comprising subjecting the sample to a magnetic field, irradiating the sample with radiofrequency electromagnetic radiation, obtaining from the sample an electrical signal indicative of the radiofrequency absorption of the sample in the magnetic field at a frequency corresponding to the .sup.13 C NMR resonance frequency for --(CH.sub.2).sub.n --, filtering the signal to exclude components due to absorption by the sample attributable to carbon atoms other than those present as --(CH.sub.2).sub.n -- and determining from the intensity of the absorption the fat content of the sample, or applying to the signal an imaging technique to determine the fat distribution in the sample. .sup.1 H decoupling is preferably employed to increase signal-to-noise ratio.The method is useful in the diagnosis of certain fat-related diseases, such as muscular dystrophy.
摘要翻译： 一种在非13C富集的生物样品，特别是人体组织中测定或成像脂肪的方法，包括使样品经受磁场，用射频电磁辐射照射样品，从样品获得指示样品的射频吸收的电信号 在对应于 - （CH 2）n-的13 C NMR共振频率的频率下的磁场中，过滤信号以排除由归属于除了作为 - （CH 2）n存在的碳原子以外的碳原子的样品的吸收的组分，以及 从吸收的强度确定样品的脂肪含量，或将信号应用于成像技术以确定样品中的脂肪分布。 1H去耦合优选地用于增加信噪比。 该方法可用于诊断某些脂肪相关疾病，如肌营养不良症。
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