Flow properties of fast three-dimensional sequences for MR angiography
Flow properties of fast three-dimensional sequences for MR angiography
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DOI：
10.1016/s0730-725x(99)00083-1
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发表时间：
1999-12-01
影响因子：
2.5
通讯作者：
Nishimura, D
中科院分区：
文献类型：
--
作者：
Irarr치zaval, P;Santos, JM;Nishimura, D
为了减少飞行时间或相位对比血管造影序列的扫描时间，可以采用快速三维k空间轨迹。最佳的3D轨迹取决于可容忍的扫描时间，读出时间，几何灵活性，流动/运动属性和其他，一种形式主义的流动/运动灵敏度比较的基础上的速度k-空间行为。它包括找到作为空间k空间位置的函数的速度k空间位置。的轨迹进行比较图形化的速度k-空间地图，模拟和一个客观的计算指数。确定了各种3D轨迹（锥体、螺旋-pr混合体、螺旋的球形堆叠、3DFT、3D回波平面和壳体）的流动/运动特性。就流动/运动灵敏度而言，锥体轨迹是最好的，然而，难以将其用于各向异性分辨率或视场。容许更多的流量敏感性，螺旋轨迹的堆栈提供了更多的几何灵活性。(C)1999 Elsevier Science Inc.
To reduce the scan time of time of flight or phase contrast angiography sequences, fast three-dimensional k-space trajectories can be employed. The best 3D trajectory depends on tolerable scan time, readout time, geometric flexibility, flow/motion properties and others, A formalism for flow/motion sensitivity comparison based on the velocity k-space behavior is presented. It consists in finding the velocity k-space position as a function of the spatial k-space position. The trajectories are compared graphically by their velocity k-space maps, with simulations and with an objective computed index. The flow/motion properties of various 3D trajectories (cones, spiral-pr hybrid, spherical stack of spirals, 3DFT, 3D echo-planar, and shells) were determined. In terms of flow/motion sensitivity the cones trajectory is the best, however, it is difficult to use it for anisotropic resolutions or fields of view. Tolerating more flow sensitivity, the stack of spirals trajectory offers more geometric flexibility. (C) 1999 Elsevier Science Inc.