FIBER ORIENTATION MAPPING W/ SPIN ECHO & FAST SPIN ECHO DIFFUSION-WEIGHTED MRI

纤维取向映射已与各向异性 使用常规自旋回波技术进行扩散测量。 然而，该方法所需的多重扩散测量 可能是耗时的。 快速自旋回波（FSE）技术具有潜力 用于提高数据采集的时间效率，尽管它 还没有被实验证明。 纤维取向将是 在体模（水中的棉线/丝线）上进行，以（a）比较 纤维取向图的准确性和效率 常规的基于自旋回波和FSE的技术，以及（B）研究 适当使用双极扩散加权梯度的优点 常规Stejskal-Tanner脉冲梯度。 后者包括 梯度交叉项影响的理论处理， FSE中的不完美重聚焦脉冲。

Fiber orientation mapping has been performed with anisotropic diffusion measurements using conventional spin echo techniques. However, the multiple diffusion measurements required by the method can be time consuming. Fast spin echo (FSE) techniques has potential for improving the time efficiency of the data acquisition, albeit it has not been shown experimentally. Fiber orientation will be performed on a phantom (cotton/silk threads in water) to (a) compare the accuracy and efficiency of fiber orientation mapping using conventional spin echo and FSE based techniques, and (b) investigate the advantages of using bipolar diffusion-weighting gradients in place of conventional Stejskal-Tanner pulsed gradients. The latter includes theoretical treatment of the effects of gradient cross-terms and imperfect refocussing pulses in FSE.