Characterizing the limits of MRI near metallic prostheses.
Characterizing the limits of MRI near metallic prostheses.
复制标题
DOI：
10.1002/mrm.25540
复制
发表时间：
2015-12
影响因子：
3.3
通讯作者：
Reeder, Scott B.
中科院分区：
文献类型：
--
作者：
Smith, Matthew R.;Artz, Nathan S.;Wiens, Curtis;Hernando, Diego;Reeder, Scott B.
关键词：
表征金属植入物附近MRI对RF激励、频率编码和化学位移编码水脂分离的基本限制。全髋关节和全膝关节置换术的多组件3D数字模型用于构建材料特异性磁化率图。金属假体附近成像的基本限制和空间关系作为距离假体表面的函数进行了研究，通过计算3D场图扰动使用一个经过验证的k-空间为基础的偶极内核。受RF激励带宽限制的区域基本上与受频率编码限制的区域重叠。一旦在脂肪分数（0至100%）和SNR（~ 100）的整个范围内体素内共振偏离超过~ 6ppm，水-脂肪分离就会发生快速分解。当前的3D多光谱成像方法不会从超过±12 kHz的激励自旋中获益很大，尽管存在来自直接邻近金属植入物的组织的该范围之外的信号。所有三个空间维度中的相位编码等方法对于空间分辨超过±12 kHz的激发带宽的自旋是必要的。在这项工作中描述的方法提供了一个基准的能力，目前的成像技术，以指导开发新的MRI方法成像近金属。
To characterize the fundamental limits of MRI near metallic implants on RF excitation, frequency encoding, and chemical shift-encoding water-fat separation. Multicomponent 3D digital models of a total hip and a total knee replacement were used to construct material specific susceptibility maps. The fundamental limits and spatial relationship of imaging near metallic prostheses were investigated as a function of distance from the prosthetic surface by calculating 3D field-map perturbations using a well-validated k-space based dipole kernel. Regions limited by the bandwidth of RF excitation overlap substantially with those fundamentally limited by frequency encoding. Rapid breakdown of water-fat separation occurs once the intra-voxel off-resonance exceeds ~6 ppm over a full range of fat-fractions (0 to 100%) and SNR (-100). Current 3D multispectral imaging methods would not benefit greatly from exciting spins beyond ±12 kHz despite the presence of signal that lies outside of this range from tissue directly adjacent to the metallic implants. Methods such as phase encoding in all three spatial dimensions are necessary to spatially resolve spins beyond an excitation bandwidth of ±12 kHz. The approach described in this work provides a benchmark for the capabilities of current imaging techniques to guide development of new MRI methods for imaging near metal.
登录
查看更多内容
影响因子：
4.4
作者：
Chen, Christina A.;Chen, Weitian;Goodman, Stuart B.;Hargreaves, Brian A.;Koch, Kevin M.;Lu, Wenmaio;Brau, Anja C.;Draper, Christine E.;Delp, Scott L.;Gold, Garry E.
通讯作者：
Gold, Garry E.
影响因子：
5.3
作者：
Kurtz, S;Mowat, F;Halpern, M
通讯作者：
Halpern, M
影响因子：
3.3
作者：
Hernando, D.;Haldar, J. P.;Liang, Z. -P.
通讯作者：
Liang, Z. -P.
影响因子：
3.3
作者：
Sharma, Samir D.;Artz, Nathan S.;Reeder, Scott B.
通讯作者：
Reeder, Scott B.
DOI：
10.1002/cmr.b.10083
发表时间：
2003-10-01
影响因子：
0.9
作者：
Salomir, R;De Senneville, BD;Moonen, CTW
通讯作者：
Moonen, CTW