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1. 发明授权

US4694249A Method for recording the nuclear magnetic resonance for use in VNMR tomography 失效
标题翻译：记录用于VNMR层析成像的核磁共振的方法
公开(公告)号：US4694249A
公开(公告)日：1987-09-15
申请号：US815118
申请日：1985-12-27
申请人： Hans Post , Dieter Ratzel , Peter Brunner , Bertold Knuttel
发明人： Hans Post , Dieter Ratzel , Peter Brunner , Bertold Knuttel
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/50 , G01R33/20
CPC分类号： A61B5/055 , G01R33/50
摘要： For recording the nuclear magnetic resonance in selected areas of a body for the purpose of representing body cross-sections in the form of images (NMR tomography), wherein the nuclear spins of a selected type present in the area of one plane of the body are subjected to a superimposed gradient field varying in the selected cross-sectional plane, and selectively excited, the excitation of the nuclear spins is effected by application of a pulse sequence which induces the nuclear spins to supply at one stage a number of chronologically successive induction signals. The induction signals corresponding to each other in chronolical sequence are then processed to obtain separate sets of image signals so that by one single measurement a sequence of cross-sectional images is obtained which differ from each other by the intensity of the excited nuclear spins which varies according to the relaxation times T.sub.1 or T.sub.2. The fact that all images have been obtained by one and the same measurement provides the possibility to determine the relaxation times T.sub.1 and/or T.sub.2 related to the individual image points and to use them on the one hand for purposes of selective image representation and, on the other hand, for improving the image quality.
摘要翻译：为了在身体的选定区域记录核磁共振，用于以图像形式（NMR层析成像）来表示身体横截面，其中存在于身体的一个平面区域中的选定类型的核自旋是经受在所选截面中变化的叠加梯度场，并且选择性地激发，核自旋的激发通过施加脉冲序列来实现，该脉冲序列诱导核自旋在一个阶段提供多个时间顺序的感应信号。然后处理按时间序列相互对应的感应信号以获得单独的图像信号组，使得通过一次单次测量，获得横截面图像序列，所述序列彼此不同，所述激发的核自旋的强度随着变化根据弛豫时间T1或T2。所有图像都通过一个相同的测量获得的事实提供了确定与各个图像点相关的弛豫时间T1和/或T2的可能性，并且一方面为了选择性图像表示的目的使用它们，并且在另一方面，为了提高图像质量。

2. 发明授权

US4558277A Method for measuring the nuclear magnetic resonance 失效
标题翻译：测量核磁共振的方法
公开(公告)号：US4558277A
公开(公告)日：1985-12-10
申请号：US474555
申请日：1983-03-11
申请人： Hans Post , Dieter Ratzel , Peter Brunner
发明人： Hans Post , Dieter Ratzel , Peter Brunner
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/483 , G01R33/56 , G01N24/08
CPC分类号： G01R33/4833 , G01R33/56
摘要： For the purpose of limiting NMR spectroscopy to a selected area of a body the said area is prepared by applying first a homogeneous magnetic field passing through the entire body and superimposing thereafter upon the said magnetic field a first magnetic field of identical orientation whose strength varies in a first sense (first field gradient), exciting thereafter all the selected nuclear spins present within the body and in addition, selectively, only the nuclear spins present in a first body plane containing the volume element and extending vertically to the said first field gradient so that the selected nuclear spins contained in this body plane are returned to the direction of the homogeneous magnetic field while the nuclear spins outside this plane receive an orientation differing from the sense of the homogeneous magnetic field. This process is repeated twice, using each time a different gradient field, so that thereafter only the nuclear spins located within the volume element selected by means of the three gradient fields are parallel to the homogeneous magnetic field and can be excited by means of one or more pulses to obtain an oscillation generating an induction signal.
摘要翻译：为了将NMR光谱限制到身体的选定区域，所述区域通过首先施加穿过整个身体的均匀磁场并在此之后叠加在所述磁场上来制备其强度变化的相同取向的第一磁场第一感觉（第一场梯度），然后激发身体内存在的所有选定的核自旋，此外，选择性地仅选择存在于包含体积元素并垂直延伸到所述第一场梯度的第一体平面中的核自旋使得包含在该体平面中的选定的核自旋返回到均匀磁场的方向，而在该平面外的核自旋接收与均匀磁场的感觉不同的取向。该过程重复两次，每次使用不同的梯度场，使得此后只有位于通过三个梯度场选择的体积单元内的核自旋平行于均匀磁场，并且可以通过一个或更多脉冲以获得产生感应信号的振荡。

3. 发明授权

US4535290A Method for measuring the nuclear magnetic resonance for NMR tomography 失效
标题翻译：用于NMR层析成像的核磁共振测量方法
公开(公告)号：US4535290A
公开(公告)日：1985-08-13
申请号：US474699
申请日：1983-03-11
申请人： Hans Post , Dieter Ratzel
发明人： Hans Post , Dieter Ratzel
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/483 , G01R33/54 , G01R33/56 , G01R33/08
CPC分类号： G01R33/482 , G01R33/56 , G01R33/4838
摘要： In NMR tomography, the nuclear spins of a selected type present in a selected area of a body are selectively excited by applying first a selection gradient field and exciting thereafter the nuclear spins by a HF signal which initially effects a rotation of the nuclear spins situated in a selected plane by an angle .alpha. of less than 90.degree., then a rotation of all selected nuclear spins by 90.degree. and finally again a rotation of the nuclear spins contained in the selected plane by an angle of 90.degree.-.alpha.. As a result thereof, the nuclear spins contained in the selected area have resumed at the end of this excitation their original orientation determined by a homogeneous magnetic field, while nuclear spins located outside this area lie within a plane extending almost vertically thereto. Thereafter, a measuring gradient field may be switched on without disturbing the orientation of the nuclear spins contained in the selected area. With the measuring gradient field switched on, the nuclear spins are now excited by a 90.degree. pulse or usual pulse sequences to produce an induction signal. The measuring processes are carried out in pairs, with the selection gradient field applied, using different excitation signals so that the nuclear spins contained in the selected area are alternately oppositely directed which means that the induction signals generated by them are phase-shifted by 180.degree., whereas the nuclear spins situated outside the selected area are shifted in the same sense so that they supply identical signals, if any.
摘要翻译：在NMR层析成像中，存在于身体的选定区域中的所选类型的核自旋通过首先施加选择梯度场并且随后通过HF信号激励核自旋来选择性地激发，该HF信号最初影响位于所选择的平面的角度α小于90°，然后所有选定的核自旋的旋转90°，最后再次将包含在所选平面中的核自旋旋转90°-α。作为其结果，包含在所选区域中的核自旋在该激发结束时已经恢复，其原始取向由均匀的磁场确定，而位于该区域外部的核自旋位于几乎垂直于其延伸的平面内。此后，可以接通测量梯度场，而不会干扰包含在所选区域中的核自旋的取向。当测量梯度场接通时，核自旋现在被90°脉冲或通常的脉冲序列激发以产生感应信号。测量过程成对地进行，使用选择梯度场，使用不同的激发信号，使得包含在所选区域中的核自旋交替相反，这意味着它们产生的感应信号相移180° 而位于所选区域之外的核自旋以相同的意义移动，使得它们提供相同的信号（如果有的话）。

4. 发明授权

US4633178A Process for the excitation of a sample for NMR tomography 失效
标题翻译：用于NMR层析成像的样品激发过程
公开(公告)号：US4633178A
公开(公告)日：1986-12-30
申请号：US723807
申请日：1985-04-16
申请人： Bernhard Strobel , Dieter Ratzel
发明人： Bernhard Strobel , Dieter Ratzel
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/561 , G01R33/20
CPC分类号： G01R33/5615 , G01R33/5617
摘要： The use of longer 180.degree. pulse sequences for the generation of spin echos is made possible according to the invention during NMR tomography using the 2d-Fourier transformation process in that the phase position and, thus, the sense of rotation of the 180.degree. pulses is reversed after every two pulses. The mirror images which appear otherwise when using the known 180.degree. pulse sequences, e.g. the Carr-Purcell-Gill-Meiboom pulse sequence, are avoided by this measure.
摘要翻译：根据本发明，在使用二维傅立叶变换处理的NMR层析成像中，使用较长的180度脉冲序列来产生自旋回波是可能的，因为相位位置，因此180°脉冲的旋转方向为每两个脉冲后反转。当使用已知的180°脉冲序列时出现的镜像，例如， Carr-Purcell-Gill-Meiboom脉冲序列被这种措施所避免。

5. 发明申请

US20050001680A1 Low-noise preamplifier, in particular, for nuclear magnetic resonance (NMR) 有权
标题翻译：低噪声前置放大器，特别是核磁共振（NMR）
公开(公告)号：US20050001680A1
公开(公告)日：2005-01-06
申请号：US10844364
申请日：2004-05-13
申请人： Dieter Ratzel
发明人： Dieter Ratzel
IPC分类号： G01R33/36 , H03F1/26 , H03F1/34 , H03F3/45
CPC分类号： G01R33/3621 , H03F1/26 , H03F1/347 , H03F2200/534 , H03F2200/541
摘要： A low-noise preamplifier with an electronic amplifying element having an input (2) and an output (4), and with a first transformer (6) having a primary winding (5) and a secondary winding (8) is characterized in that the input (2) of the electronic amplifying element is the base of a transistor, the gate (G) of a field effect transistor (FET) or the grid of a vacuum tube, and the output (4) of the electronic amplifying element is the collector, the drain (D) or the anode, the output current (Ip) being passed from the electronic amplifying element through the primary winding (5) of the first transformer (6) to the output (7) of the preamplifier, wherein the secondary winding (8) of the first transformer (6) is connected to the input (2) of the electronic amplifying element. This preamplifier can be operated with extremely low noise and at any input impedance, in particular, at 50 ohms or 75 ohms.
摘要翻译：具有输入（2）和输出（4）的电子放大元件以及具有初级绕组（5）和次级绕组（8）的第一变压器（6）的低噪声前置放大器的特征在于，电子放大元件的输入（2）是晶体管的基极，场效应晶体管（FET）的栅极（G）或真空管的栅极，并且电子放大元件的输出（4）是集电极，漏极（D）或阳极，输出电流（Ip）从电子放大元件通过第一变压器（6）的初级绕组（5）传送到前置放大器的输出端（7），其中第一变压器（6）的次级绕组（8）连接到电子放大元件的输入（2）。该前置放大器可以以非常低的噪声和任何输入阻抗操作，特别是在50欧姆或75欧姆。

6. 发明授权

US5355086A Method for the generation of an NMR spectrum without side-bands 失效
标题翻译：没有边带产生NMR谱的方法
公开(公告)号：US5355086A
公开(公告)日：1994-10-11
申请号：US12578
申请日：1993-02-03
申请人： Dieter Ratzel
发明人： Dieter Ratzel
IPC分类号： G01R33/565 , G01R33/20
CPC分类号： G01R33/56518
摘要： In a method for the generation of a nuclear magnetic resonance (NMR) spectrum from a measuring volume, which is exposed to a highly homogeneous stationary magnetic field B.sub.0, a radio frequency (RF)-pulse is irradiated in a first run into the measuring volume in order to excite the concerned nuclear spins; at least one magnetic gradient field G is switched, for example for selecting a certain slice from the measuring volume and after switching off the magnetic gradient field G, a first data set is recorded which contains the observable measuring signals from the measuring volume, subsequently the method is repeated in a second run with a magnetic gradient field -G which has the opposite polarity to the magnetic gradient field G, whereas the remaining experimental parameters of the first run are maintained, wherein after switching off the magnetic gradient field -G a second data set is recorded and added to the first data set. In this manner, side bands in NMR spectra and artifacts in NMR-images, respectively, can be compensated, which are caused by disturbances of the magnetic field B.sub.0 owing to the switching of the gradient field G.
摘要翻译：在从暴露于高度均匀的固定磁场B0的测量体积产生核磁共振（NMR）光谱的方法中，将射频（RF）脉冲在第一次运行中照射到测量体积以激发有关的核旋转; 切换至少一个磁梯度场G，例如用于从测量体积中选择某个切片，并且在切断磁梯度场G之后，记录包含来自测量体积的可观察测量信号的第一数据组，方法在具有与磁梯度场G相反的极性的磁梯度场-G的第二次运行中重复，而第一次运行的剩余实验参数被维持，其中在关闭磁梯度场-G之后，第二次数据集被记录并添加到第一数据集。以这种方式，NMR光谱中的边带和NMR图像中的伪像可以被补偿，这是由于梯度场G的切换导致的磁场B0的干扰引起的。

7. 发明授权

US5138261A Nuclear magnetic resonance tomograph 失效
标题翻译：核磁共振TOMOGRAPH
公开(公告)号：US5138261A
公开(公告)日：1992-08-11
申请号：US548166
申请日：1990-07-03
申请人： Dieter Ratzel
发明人： Dieter Ratzel
IPC分类号： A61B5/055 , G01R33/343 , G01R33/389 , G01R33/58
CPC分类号： G01R33/583 , G01R33/343
摘要： A nuclear magnetic resonance tomograph comprises a magnet surrounding a measuring space for receiving an object under test, e.g. a human body. A coil is provided for generating a high-frequency magnetic field within the measuring space. The coil is fed by a transmitter comprising a stage for adjusting the amplitude of a high-frequency current generated by the transmitter. A high-frequency magnetic field sensor is arranged at a predetermined calibration location outside the measuring space for measuring the high-frequency magnetic field strength prevailing at the predetermined calibration location. For calibrating the high-frequency magnetic field strength during a tomography measurement, the coil with the object under test inside is subjected to a test current and the resulting high-frequency magnetic field amplitude is sensed. From the value of the test current and the sensed high-frequency magnetic field strength one can calculate a measuring current to be fed into the coil for generating a desired high-frequency magnetic field strength within the measuring space.
摘要翻译：核磁共振断层摄影机包括围绕用于接收被测物体的测量空间的磁体，例如，一个人体提供线圈，用于在测量空间内产生高频磁场。线圈由包括用于调节由发射器产生的高频电流的振幅的级的发射器馈送。高频磁场传感器布置在测量空间外部的预定校准位置处，用于测量在预定校准位置处占优势的高频磁场强度。为了在断层摄影测量期间校准高频磁场强度，将具有被测物体的线圈进行测试电流，并且感测所得到的高频磁场振幅。根据测试电流的值和感测的高频磁场强度，可以计算要馈送到线圈中的测量电流，以在测量空间内产生期望的高频磁场强度。

8. 发明授权

US5572130A Method and apparatus for the production of an NMR tomography image using an array of surface coils and multiplexers 失效
标题翻译：用于使用表面线圈和多路复用器阵列生产NMR断层摄影图像的方法和装置
公开(公告)号：US5572130A
公开(公告)日：1996-11-05
申请号：US421045
申请日：1995-04-12
申请人： Dieter Ratzel
发明人： Dieter Ratzel
IPC分类号： G01R33/3415 , G01R33/28
CPC分类号： G01R33/3415
摘要： In a method and apparatus for the production of a nuclear magnetic resonance (NMR) tomography image with radio frequency (RF) signals from an extended measuring object (11) being detected by n surface coils (2a, 2b, 2c, 2d) of an NMR apparatus, whereby n>1, and the n RF signals are separately preamplified by n preamplifiers (3a, 3b, 3c, 3d) each assigned to one of the n surface coils (2a, 2b, 2c, 2d), and subsequently further amplified and detected in a phase sensitive fashion, as a result of which a low frequency signal is obtained in each case which is introduced to one of n low pass filters (5a, 5b, 5c, 5d) of an analog/digital converter (ADC) and whereby n partial images are produced in a computer (8) from the n signals obtained in this fashion and assembled into a single NMR tomography image of the measuring object (11) in a region of interest, the signals emanating from the n low pass filters (5a, 5b, 5c, 5d) are introduced to a single ADC (7) via a first multiplexing circuit (6) to be digitized and passed on to the computer (8). In this fashion is it possible for n-1 high speed ADC'S as well as a complicated interface for the input of the signals from the different measuring chains into the computer to be dispensed with and the utility of an already existing NMR apparatus can be significantly increased.
摘要翻译：在用于生产来自扩展测量对象（11）的射频（RF）信号的核磁共振（NMR）断层摄影图像的方法和装置由n个表面线圈（2a，2b，2c，2d）检测到的 NMR装置，其中n≥1，并且n个RF信号由分配给n个表面线圈（2a，2b，2c，2d）中的一个的n个前置放大器（3a，3b，3c，3d）分别预放大，以相敏方式进行放大和检测，其结果是在每个情况下获得低频信号，该信号被引入模拟/数字转换器（ADC）的n个低通滤波器（5a，5b，5c，5d）之一），并且由此在计算机（8）中从以这种方式获得的n个信号中产生n个部分图像，并将其组装成感兴趣区域中的测量对象（11）的单个NMR断层摄影图像，从n个低频发出的信号通过滤波器（5a，5b，5c，5d）经由第一复用电路（6）被引入单个ADC（7）被数字化并传递到计算机（8）。以这种方式，n-1个高速ADC的可能性以及从不同测量链到计算机的信号输入的复杂接口被省去，并且已经存在的NMR装置的效用可以显着增加。

9. 发明授权

US5248942A Method of exciting a sample for NMR tomography 失效
标题翻译：提取核磁共振成像样品的方法
公开(公告)号：US5248942A
公开(公告)日：1993-09-28
申请号：US795510
申请日：1991-11-21
申请人： Dieter Ratzel , Erich Treiber , Bernhard Strobel
发明人： Dieter Ratzel , Erich Treiber , Bernhard Strobel
IPC分类号： G01R33/561
CPC分类号： G01R33/561
摘要： In particular with 3D tomography, it is necessary to acquire a large number of individual spectra. Therefore it is advisable to reduce the time needed for the acquisition of a single spectrum without loosing too much in signal-to-noise ratio. To a significant extent, this time is determined by the relaxation time of the spins. Prior to each excitation a significant quantity of these spins have to return into their equilibrium (z-direction of the homogeneous magnetic field) in order to create a usable signal with the next excitation. For spins with long relaxation times T.sub.2 this time can be reduced by a -90.degree. pulse 12 that coincides with the center of the last spin echo 9 with appropriate application of the gradient fields. This -90.degree. pulse returns the x-y magnetization that exists in the x-y plane into the z-direction. The diagnostic relevance can be significantly increased by such a procedure.
摘要翻译：特别是通过3D断层摄影，需要获取大量的单个光谱。因此，建议减少采集单个频谱所需的时间，而不会使信噪比过大。在很大程度上，这个时间是由旋转的松弛时间决定的。在每次激发之前，大量的这些旋转必须返回到它们的平衡（均匀磁场的z方向），以便产生具有下一个激励的可用信号。对于长松弛时间T2的自旋，此时可以通过适当应用梯度场而与最后自旋回波9的中心一致的-90°脉冲12减小。该-90°脉冲将x-y平面中存在的x-y磁化返回到z方向。通过这种程序可以显着增加诊断相关性。

10. 发明授权

US4896112A Method for generating spin echo pulse sequences in a nuclear spin tomograph, and nuclear spin tomograph adapted for carrying out such method 失效
标题翻译：用于在核自旋断层扫描仪中产生自旋回波脉冲序列的方法，以及适于执行这种方法的核自旋断层扫描仪
公开(公告)号：US4896112A
公开(公告)日：1990-01-23
申请号：US241440
申请日：1988-09-07
申请人： Dieter Ratzel , Norbert Schuff
发明人： Dieter Ratzel , Norbert Schuff
IPC分类号： A61B10/00 , A61B5/055 , G01R33/44 , G01R33/48 , G01R33/565
CPC分类号： G01R33/56518
摘要： In nuclear spin tomography disturbances are encountered as a result of the insertion of the gradient fields, which disturbances are due to the generation of eddy currents and lead to field distortions making themselves felt, among other things, in the rapid decay of the echo signals of spin echo pulse sequences, i.e. in disturbances of the rephasing conditions. According to the invention, the rephasing conditions required for generating spin echo impulse sequences can be established either by varying the value of the static magnetic field between the excitation pulse and the next following rf pulse of a spin echo pulse sequence, or else by adjusting the interval between the excitation pulse and the next following rf pulse to a value different from half the interval between the subsequent rf pulses.
摘要翻译：在核自旋断层扫描中，由于插入梯度场而遇到干扰，这些干扰是由涡流的产生引起的，并导致场失真，使得自身在回波信号的快速衰减自旋回波脉冲序列，即重构条件的干扰。根据本发明，可以通过改变激发脉冲与自旋回波脉冲序列的下一个跟随rf脉冲之间的静态磁场的值来建立产生自旋回波脉冲序列所需的重定位条件，或者通过调整激励脉冲和下一个跟随rf脉冲之间的间隔到不同于后续rf脉冲间隔的一半的值。

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