Feasibility of using linearly polarized rotating birdcage transmitters and close-fitting receive arrays in MRI to reduce SAR in the vicinity of deep brain simulation implants.
Feasibility of using linearly polarized rotating birdcage transmitters and close-fitting receive arrays in MRI to reduce SAR in the vicinity of deep brain simulation implants.
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DOI：
10.1002/mrm.26220
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发表时间：
2017-04
影响因子：
3.3
通讯作者：
Wald, Lawrence L.
中科院分区：
文献类型：
--
作者：
Golestanirad, Laleh;Keil, Boris;Angelone, Leonardo M.;Bonmassar, Giorgio;Mareyam, Azma;Wald, Lawrence L.
关键词：
出于安全考虑，深部脑刺激(DBS)植入物患者的MRI受到严格限制，包括植入物附近射频(RF)场的高水平局部特定吸收率(SAR)和相关的RF诱导加热。这项研究证明了使用旋转线极化鸟笼发射机和32通道近贴合接收阵列来显著降低DBS患者MRI中的局部SAR的可行性。利用一般的DBS引线几何形状和注入路径进行了电磁模拟和体模实验。这项技术是基于机械旋转线性鸟笼发射器，使其零电场区域与植入物对齐，同时使用紧密配合的接收阵列来显著提高图像的信噪比。研究发现，发射机的零电场区域在1.5特斯拉时足够厚，可以用离开平面30度的线段包围DBS引线轨迹，以及带有环状线段的引线。此外，SAR降低对组织特性不敏感，并且插入紧密配合的32通道接收阵列不会降低SAR降低性能。旋转线性鸟笼和32通道紧密配合接收阵列的组合为未来改善DBS植入物患者的成像提供了一项有前途的技术。
MRI of patients with deep brain stimulation (DBS) implants is strictly limited due to safety concerns, including high levels of local specific absorption rate (SAR) of radiofrequency (RF) fields near the implant and related RF-induced heating. This study demonstrates the feasibility of using a rotating linearly polarized birdcage transmitter and a 32-channel close-fit receive array to significantly reduce local SAR in MRI of DBS patients. Electromagnetic simulations and phantom experiments were performed with generic DBS lead geometries and implantation paths. The technique was based on mechanically rotating a linear birdcage transmitter to align its zero electric-field region with the implant while using a close-fit receive array to significantly increase signal to noise ratio of the images. It was found that the zero electric-field region of the transmitter is thick enough at 1.5 Tesla to encompass DBS lead trajectories with wire segments that were up to 30 degrees out of plane, as well as leads with looped segments. Moreover, SAR reduction was not sensitive to tissue properties, and insertion of a close-fit 32-channel receive array did not degrade the SAR reduction performance. The ensemble of rotating linear birdcage and 32-channel close-fit receive array introduces a promising technology for future improvement of imaging in patients with DBS implants.
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影响因子：
3.7
作者：
Kahan J;Mancini L;Urner M;Friston K;Hariz M;Holl E;White M;Ruge D;Jahanshahi M;Boertien T;Yousry T;Thornton JS;Limousin P;Zrinzo L;Foltynie T
通讯作者：
Foltynie T
影响因子：
3.3
作者：
Keil, Boris;Blau, James N.;Biber, Stephan;Hoecht, Philipp;Tountcheva, Veneta;Setsompop, Kawin;Triantafyllou, Christina;Wald, Lawrence L.
通讯作者：
Wald, Lawrence L.
影响因子：
7.6
作者：
Greenberg, Benjamin D.;Malone, Donald A.;Rasmussen, Steven A.
通讯作者：
Rasmussen, Steven A.
影响因子：
9.9
作者：
Hubble, JP;Busenbark, KL;Koller, WC
通讯作者：
Koller, WC
DOI：
10.1002/jmri.24152
发表时间：
2014-02
期刊：
Journal of magnetic resonance imaging : JMRI
影响因子：
--
作者：
Krishnamurthy N;Zhao T;Ibrahim TS
通讯作者：
Ibrahim TS