Unal O, Korosec F R, Frayne R, Strother C M, Mistretta C A
Department of Medical Physics, University of Wisconsin, Madison 53792-3252, USA.
Magn Reson Med. 1998 Sep;40(3):356-62. doi: 10.1002/mrm.1910400304.
A new, fast, 2D MR imaging technique allowing passive catheter visualization adequate for use as a tool for guiding the movement of a catheter during endovascular procedures is described. This imaging technique samples low spatial frequencies more often than high spatial frequencies; it also uses both k-space view sharing and temporal interpolation. Unlike other techniques for passive visualization that exploit magnetic-susceptibility-induced artifacts, we have adopted a strategy that takes advantage of the T1-shortening effect of paramagnetic contrast agents, such as Gd-DTPA and a projection dephaser. This not only permits visualization of the entire catheter length but also minimizes the risk of intravascular heating. Using this method, a temporal frame rate of up to eight images per second and a tip localization accuracy of +/- 1mm (root mean square difference) can be achieved.
本文描述了一种新的、快速的二维磁共振成像技术，该技术能够实现对无源导管的可视化，足以用作血管内手术期间引导导管移动的工具。这种成像技术对低空间频率的采样比高空间频率更频繁；它还使用了k空间视图共享和时间插值。与其他利用磁敏感性诱导伪影进行无源可视化的技术不同，我们采用了一种利用顺磁性造影剂（如钆喷酸葡胺）的T1缩短效应和投影去相位器的策略。这不仅可以实现对整个导管长度的可视化，还能将血管内热的风险降至最低。使用这种方法，可以实现高达每秒八帧图像的时间帧率和±1mm（均方根差）的尖端定位精度。
