Verfahren zur Kernspintomographischen Aufnahme von bewegten Objekten
    6.
    发明公开
    Verfahren zur Kernspintomographischen Aufnahme von bewegten Objekten 有权
    维尔法赫恩·祖尔诺斯科

    公开(公告)号:EP1598676A2

    公开(公告)日:2005-11-23

    申请号:EP05015592.8

    申请日:2004-06-17

    IPC分类号: G01R33/28

    摘要: Ein Verfahren der Kernspinresonanz(=NMR)-Tomographie zur Untersuchung eines Zielobjekts, bei dem Hochfrequenz(=HF)-Impulse in ein Zielvolumen einstrahlt und/oder HF-Impulse aus dem Zielvolumen detektiert werden, wobei das Zielvolumen durch die Frequenz der HF-Impulse und/oder durch Magnetfeldgradienten bestimmt ist, und wobei das Zielobjekt während der NMR-Datenaufnahme relativ zum NMR-Tomographen bewegt wird, ist dadurch gekennzeichnet, dass die Frequenz der HF-Impulse und/oder die Magnetfeldgradienten während der NMR-Datenaufnahme so verändert werden, dass das von den HF-Impulsen erfasste Zielvolumen während der NMR-Datenaufnahme mit der gleichen Geschwindigkeit und Bewegungsrichtung wie das Zielobjekt relativ zum NMR-Tomographen bewegt wird. Damit wird ein Verfahren zur Untersuchung eines bezüglich des NMR-Tomographen während der NMR-Datenaufnahme bewegten Zielobjekts vorgestellt, das schnell und einfach durchführbar ist.

    摘要翻译: 该方法包括将射频(RF)脉冲照射到目标体积中,并且检测来自目标体积的RF脉冲。 目标体积由RF脉冲的频率和/或通过磁场梯度决定。 在NMR数据采集期间,目标物体相对于NMR层析成像仪移动。 在NMR数据采集期间,RF脉冲和/或磁场梯度的频率发生变化,使得RF脉冲覆盖的目标体积以与目标物体相同的速度和相同的运动方向相对于NMR层析成像 在NMR数据采集期间。 在NMR数据采集期间,调查目标体积。 目标对象平行于切片形目标体积的表面法线移动。 NMR数据采集期间磁场梯度保持恒定,只有RF脉冲的频率发生变化。

    MR imaging apparatus
    7.
    发明公开
    MR imaging apparatus 失效
    Apparat zur Bilderzeugung mittels magnetischer Resonanz

    公开(公告)号:EP0686855A1

    公开(公告)日:1995-12-13

    申请号:EP95108081.1

    申请日:1995-05-26

    IPC分类号: G01R33/563

    摘要: An MR imaging apparatus using NMR phenomenon includes a main magnet, a first, a second and a third gradient field coils, a RF coil, a gradient field controller connected to the first, second and third gradient field coils, a RF controller connected to the RF coil, a waveform generator, a carrier wave generator, an amplitude modulator, a RF controller connected to the RF coil, and a data processor. The waveform generator generates a modulating signal expressed by F(t) = A {cos (ωt) - cos (εωt)} / t , where A is an amplitude coefficient, ε is a non-excitation band coefficient, and ω is a frequency of the modulating signal. The RF controller causes the RF coil, in each pulse sequence, to transmit a RF signal and to apply, to the RF signal, a modulated wave outputted from the amplitude modulator as an MTC pulse having a frequency component slightly offset from a resonance frequency of free water protons, and a resonance frequency component of free water protons. The data processor collects data from the NMR signal detected by the RF coil, and reconstructs a sectional image from the data.

    摘要翻译: 使用NMR现象的MR成像装置包括主磁体,第一,第二和第三梯度场线圈,RF线圈,连接到第一,第二和第三梯度场线圈的梯度场控制器,连接到 RF线圈,波形发生器,载波发生器,幅度调制器,连接到RF线圈的RF控制器和数据处理器。 波形发生器产生由F(t)= A {cos(ω-t)-cos(εωωt)} / t表示的调制信号,其中A是振幅系数,ε是非激励频带系数,ω 是调制信号的频率。 RF控制器使得RF线圈在每个脉冲序列中传送RF信号并将其从RF振幅调制器输出的调制波作为MTC脉冲施加,该脉冲具有与谐振频率稍微偏离的频率分量 游离水质子和自由水质子的共振频率分量。 数据处理器从由RF线圈检测的NMR信号中收集数据,并从数据中重建截面图像。

    Magnetic resonance systems
    9.
    发明公开
    Magnetic resonance systems 失效
    磁共振系统

    公开(公告)号:EP0412747A3

    公开(公告)日:1991-10-09

    申请号:EP90308617.1

    申请日:1990-08-06

    IPC分类号: G01R33/54

    CPC分类号: G01R33/3607

    摘要: A magnetic resonance imaging system includes one or more digital transmitters (B), one or more digital receivers (C), and digital data processing circuitry (D) which are all clocked and controlled by a single clock (F). Each digital transmitter includes a numerically controlled modulated oscillator (20) which processes digital phase and frequency signals to produce an output which addresses a wave-form map stored in a PROM (22). Each wave-form output of the PROM is multiplied (24) by a digital amplitude profile signal to generate phase, frequency, and amplitude modulated digital RF signals. A clock gate (30) controls clocking of the digital modulation to create RF pulses. A digital-to-analog converter (28) converts the digital information to an analog RF pulse which is applied to a subject in an image region. The receivers each include an analog-to-digital converter (60) which digitizes the magnetic resonance signal emanating from the subject in the image region with four fold oversampling. A pair of FIR filters (62a, 62b) multiply the digital resonance signal by digital sine and cosine filter coefficients to create in-phase and out-of-phase digital magnetic resonance signal components. After additional digital filtering (64a, 64b), the digital in-phase and quadrature components are Fourier transformed (70) and accumulated in an image memory (72) to form an image representation.

    3D image reconstruction method and apparatus for placing 3D structure within common oblique or contoured slice-volume without loss of volume resolution
    10.
    发明公开
    3D image reconstruction method and apparatus for placing 3D structure within common oblique or contoured slice-volume without loss of volume resolution 失效
    3D图像重建的方法和装置用于在一个共同的倾斜3D结构的放置或约束体积切片体积,而不损失分辨率。

    公开(公告)号:EP0377267A2

    公开(公告)日:1990-07-11

    申请号:EP89306054.1

    申请日:1989-06-15

    IPC分类号: G06T1/00 G01R33/48 G01R33/54

    摘要: Variable voxel shifts required for shifting a 3D structure into a common oblique or contoured slice volume based on an existing 3D image are achieved by effecting variable f(x,y) phase shifts in corresponding frequency domain data parallel to a selected axis dimension and then reconstructing a new three-dimensional image having the 3D structure all located within a common oblique or otherwise contoured slice volume such that it may viewed in a single planar image display without loss of volume resolution. Equivalent convolution processes within the spatial domain may also be employed. Oblique or curved reconstructions can thus be made using either originally acquired frequency domain data (used to construct the original image) or frequency domain data obtained by inverse Fourier transforming the available spatial domain data of the images themselves.

    摘要翻译: 用于3D结构转移到一个共同的倾斜或基于现有的3D图像上的轮廓切片体积所需可变​​体素位移通过实现在平行对应的频域数据到所选择的轴线尺寸变量f(X,Y)的相移,然后重构取得 具有三维结构全部位于一个共同的倾斜内或以其它方式检查切片轮廓体积这样做是可以在单个平面图像显示观看没有分辨率损耗量新的三维图像。 空间域中内等效卷积过程因此可以被使用。 斜或弯曲的重建可以通过使用逆傅立叶因此获得原始采集要么频域数据(用于构建原始图像)或频域数据变换图像本身的可用空间域的数据作出的。