F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland 21231, USA.
Magn Reson Med. 2013 Feb;69(2):516-23. doi: 10.1002/mrm.24271. Epub 2012 Apr 12.
An MRI segmentation technique based on collecting two additional saturation transfer images is proposed as an aid for improved detection of chemical exchange saturation transfer agents. In this approach, the additional images are acquired at saturation frequencies of -12.5 and -50 ppm. Use of the ratio of these images allows differentiation of voxels with low magnetization transfer contrast (such as fat, cerebrospinal fluid, edema, or blood) from target tissue voxels using a global threshold determined by histogram analysis. We demonstrate that this technique can reduce artifacts, in vitro, in a phantom containing tubes with chemical exchange saturation transfer contrast agent embedded in either crosslinked bovine serum albumin or buffer, and in vivo for detecting diamagnetic CEST (DIACEST) liposomes injected into mice.
提出了一种基于采集两个附加饱和传递图像的 MRI 分割技术，作为提高化学交换饱和传递试剂检测的辅助手段。在这种方法中，附加图像在饱和频率为-12.5 和-50 ppm 处采集。使用这些图像的比值，可以使用通过直方图分析确定的全局阈值，将具有低磁化转移对比度（如脂肪、脑脊液、水肿或血液）的体素与目标组织体素区分开来。我们证明，该技术可以减少含有嵌入交联牛血清白蛋白或缓冲液中的化学交换饱和传递造影剂的管的体外体模中的伪影，并可以检测注射到小鼠体内的抗磁性 CEST（DIACEST）脂质体。
