低场MRI系统中线扫描扩散张量成像方法的研究

磁共振扩散张量成像(DTI)是在扩散加权成像(DWI)基础上发展起来的一种新型技术，可以无创伤显示脑白质纤维，诊断脑白质病变. 但是由于各种原因，DTI一般只在超导高场磁共振成像(MRI)仪器上进行，这就限制了这一重要诊断手段临床应用的广泛性. 本文在低场磁共振成像系统上应用线扫描实现了扩散张量成像，并测量了健康志愿者大脑内主要解剖结构的表观扩散系数(ADC)和各项异性分数(FA)，得到的数据与高场仪器上的相关数据比较是吻合的. 因此临床上使用在低场强上得到的DTI图像评价脑白质是可行的，而且通常在临床上这也是足够的.

Line-Scan Diffusion Tensor Imaging on Low Field Strength MRI Scanner

Diffusion tensor imaging (DIT) is a new magnetic resonance imaging (MRI) technology developed from diffusion-weighted imaging, and can be used for tracking white matter tracts and diagnosis of white matter disorders. To date, most of the DTI studies are carried out on high field MRI scanners. In this study, a line-scan DTI method was implemented on a 0.35 T permanent magnet open MRI scanner, and used to measure the apparent diffusion coefficient (ADC) and the fractional anisotropy (FA) values in normal adult brain. The ADC and FA values measured in this study were found to be comparable with those obtained on high field strength scanners. It was concluded that it is feasible to perform DTI on low field strength MRI scanners under clinical settings for diagnostic purposes.