大脑快速 T1 图谱成像研究

大脑快速 T1图谱成像是一种量化磁共振成像技术，可以为帕金森、癫痫、肝脑病等脑部疾病的诊断提供重要参考依据。现有的大脑快速 T1图谱成像技术可以将成像速度提高到几秒/层，然而主磁场、发射场的不均性(尤其在高场下)以及大脑内部结构的磁化率差异，降低了成像精确性，限制了其在临床上的推广应用。针对上述缺点，文章提出一种基于 TurboFLASH技术的大脑快速 T1图谱成像方法，并先后在计算机仿真实验、仿体以及人体试验中进行验证。实验结果表明，文章提出的方法测得的大脑组织 T1值与金标准及文献中报导的值非常接近(误差＜3%)，同时扫描速度提高到3秒/层，空间分辨率为1.1 mm×1.1 mm×4 mm，2分钟内即可完成全脑采集。

The Study of Fast T1 Mapping of Human Brain

Fast brain T1 mapping is a quantitative technique of magnetic resonance imaging, and can provide important reference for the diagnosis of several brain diseases, such as Parkinson, epilepsy and hepatic encephalopathy. Fast T1 mapping techniques proposed previously had sped up acquisition to several seconds per slice. However, most of these techniques suffered seriously from the ifeld inhomogeneity of main ifeld, transmit ifeld and susceptibility artifacts, which decreased the imaging accuracy and limited the clinic applications. To overcome the above mentioned shortcomings, we proposed a fast brain T1 mapping technique based on TurboFLASH and evaluated it on computer simulation, phantom experiment, and human brain T1 mapping. Results showed that T1 values from the proposed method were very close to the gold standard and literature (differences being less than 3%). Besides, the proposed technique can increase the acquisition speed to 3s per slice (with a slice resolution of 1.1 mm×1.1 mm) and 2 min for the whole brain (with a 4 mm slice distance).