公开(公告)号：EP2147329A1

公开(公告)日：2010-01-27

申请号：EP08757081.8

申请日：2008-05-02

申请人： National Research Council of Canada

发明人： SHARP, Jonathan ,  KING, Scott

IPC分类号： G01R33/54 ,  G01R33/32

CPC分类号： G01R33/4831 ,  G01R33/34076 ,  G01R33/3415 ,  G01R33/3607 ,  G01R33/4833

摘要： Herein a method for slice selection is provided in an MRI process, the method involves controlling a transmit array by adding low flip angle RF pulses interspersed between refocusing pulses that are used to move a k-space weighting function with respect to one or more B l fields used to deposit energy according to a desired k-space weighting function. The low flip angle pulses deposit energy so that an envelope traced by the low flip angle pulses in the k-space weighting function is related to a desired spatially excited region of the sample volume, for example by a Fourier transform, if the phase encoding directions are linear axes that coordinatize the sample volume, and the B l fields have linear phase gradients.

摘要翻译： 这里，在MRI处理中提供了切片选择的方法，该方法包括通过将用于相对于一个或多个B 1移动k空间加权函数的重聚焦脉冲之间的散布的低翻转角RF脉冲相加来控制发射阵列 用于根据期望的k空间加权函数来存储能量的场。 低翻转角脉冲沉积能量，使得通过k空间加权函数中的低翻转角脉冲跟踪的包络与样本体积的期望的空间激发区域有关，例如通过傅立叶变换，如果相位编码方向 是使样本体积协调的线性轴，B 1场具有线性相位梯度。

公开(公告)号：EP2147328A1

公开(公告)日：2010-01-27

申请号：EP08748267.5

申请日：2008-05-02

申请人： National Research Council of Canada

发明人： KING, Scott ,  SHARP, Jonathan

IPC分类号： G01R33/54 ,  G01R33/32 ,  G01R33/38

CPC分类号： G01R33/3415 ,  G01R33/34061 ,  G01R33/482 ,  G01R33/4831 ,  G01R33/5612 ,  G01R33/5617

摘要： Accumulated spin magnetization phase within a RF MRI procedure can be used for providing an orderly k-space traversal. By operating a transmit array adapted to produce two Bl fields in alternation, where the Bl fields are substantially uniform in amplitude over a sample volume of the MRI setup, and the Bl fields have respective spatial phase distributions such that selection of a difference in spatial derivatives of the spatial phase distributions permits control over a size of a step in k- space applied by successive refocusing pulses for generating the B l fields in alternation. Each alternating refocusing pulse issued within a T2 time causes a step through k-space in an encoding direction determined by the difference in spatial derivatives.

公开(公告)号：EP1658511A1

公开(公告)日：2006-05-24

申请号：EP04737996.1

申请日：2004-07-23

申请人： NATIONAL RESEARCH COUNCIL OF CANADA

发明人： KING, Scott

IPC分类号： G01R33/34 ,  G01R33/3415

CPC分类号： G01R33/3415

摘要： An array coil for sensing signals in magnetic resonance experiments incorporates the traditional loop-butterfly array elements at spaced positions along an axis of the sample with additional stacked twisted loops and/or twisted butterfly elements. The twisted loop and twisted butterfly elements are centred along between the standard loop-butterfly array elements. The twisted array elements are naturally isolated from both the loop and butterfly. Alternatively, for a two dimensional mesh array of loop elements, additional twisted loop array elements are added with both longitudinal and transverse orientations, again centered between loop elements. The goal is to allow separation of loop and/or butterfly elements of linear (Spine), 2D planar arrays (Cardiac) or cylindrical arrays of curved array elements (Head), for improved parallel MRI capabilities such as the SENSE or SMASH techniques, but to recover the SNR lost in between the elements and improve the g-factor of the total array with additional orthogonal array elements.