DEVELOPMENT OF ADVANCED CHEMICAL SHIFT IMAGING (CSI) TECHNIQUES

化学位移成像(CSI)是体内研究的首选方法 局域光谱学。然而，几个持续存在的障碍仍然 仍然适用于质子以外的原子核，特别是31P 和19F CSI在本申请的项目中提出。首先， 敏感度低。第二个和几个结果，测量 都很长，因此，在临床过程中只能观察到一个细胞核， 即使从另一个人那里得到的信息是重要的和被寻求的。第三， 目前的傅立叶重建方法，由于其 计算的便利性和简单性，导致了一种 将来自一个体素的信号与其相邻体素混合。这件艺术品， 称为体素出血，会导致光谱污染并影响CSI 总体而言。 我们建议从三个角度解决这些困难。首先，要使用 从1H到灵敏度较低的31P的偏振转移技术 增加后者的信号，并用于第二项目。第二， 开发同时捕获技术，使1H去耦合 在一次临床检查中获得31P和19F CSI。第三, 开发非傅立叶变换技术，利用先验知识 从质子图像，将提高CSI的准确性 重建。

Chemical Shift Imaging (CSI) is the method of choice for in vivo localized spectroscopy. However, several persistent obstacles still remain in its application to nuclei other than protons, specifically 31P and 19F CSI proposed in projects of this application. First, the sensitivity is low. Second and several consequents, the measurements are long, thus, only one nucleus can be observed in a clinical session, even if information from another is significant and sought. Third, the current Fourier reconstruction methods, widely used because of their computational convenience and simplicity, result in an artifact that intermixes signal from one voxel, with its its neighbors. This artifact, known as A voxel bleed, leads to spectral-contamination and impacts CSI in general. We propose to address these difficulties from three angles. First, to use polarization transfer techniques from 1H to the less sensitive 31P to increase the signal of the latter and to be used in project II. Second, to develop simultaneous acquisition techniques that will allow 1H decoupled 31P and 19F CSI acquisition during a single clinical examination. Third, to develop non-Fourier transform techniques that, using prior knowledge from the proton images, will improve the accuracy of CSI reconstruction.