Guhaniyogi Shayan, Chu Mei-Lan, Chang Hing-Chiu, Song Allen W, Chen Nan-Kuei
Brain Imaging and Analysis Center, Duke University Medical Center, Durham, North Carolina, USA.
Magn Reson Med. 2016 Feb;75(2):639-52. doi: 10.1002/mrm.25624. Epub 2015 Mar 11.
To develop new techniques for reducing the effects of microscopic and macroscopic patient motion in diffusion imaging acquired with high-resolution multishot echo-planar imaging.
The previously reported multiplexed sensitivity encoding (MUSE) algorithm is extended to account for macroscopic pixel misregistrations, as well as motion-induced phase errors in a technique called augmented MUSE (AMUSE). Furthermore, to obtain more accurate quantitative diffusion-tensor imaging measures in the presence of subject motion, we also account for the altered diffusion encoding among shots arising from macroscopic motion.
MUSE and AMUSE were evaluated on simulated and in vivo motion-corrupted multishot diffusion data. Evaluations were made both on the resulting imaging quality and estimated diffusion tensor metrics.
AMUSE was found to reduce image blurring resulting from macroscopic subject motion compared to MUSE but yielded inaccurate tensor estimations when neglecting the altered diffusion encoding. Including the altered diffusion encoding in AMUSE produced better estimations of diffusion tensors.
The use of AMUSE allows for improved image quality and diffusion tensor accuracy in the presence of macroscopic subject motion during multishot diffusion imaging. These techniques should facilitate future high-resolution diffusion imaging.
开发新技术以减少在高分辨率多激发回波平面成像获取的扩散成像中微观和宏观患者运动的影响。
先前报道的多重敏感性编码（MUSE）算法被扩展以考虑宏观像素配准错误以及在一种称为增强MUSE（AMUSE）的技术中运动引起的相位误差。此外，为了在存在受试者运动的情况下获得更准确的定量扩散张量成像测量值，我们还考虑了宏观运动引起的各次激发之间扩散编码的改变。
在模拟的和体内运动损坏的多激发扩散数据上评估MUSE和AMUSE。对所得成像质量和估计的扩散张量指标进行评估。
与MUSE相比，发现AMUSE可减少宏观受试者运动导致的图像模糊，但在忽略改变的扩散编码时会产生不准确的张量估计。在AMUSE中纳入改变的扩散编码可对扩散张量进行更好的估计。
在多激发扩散成像期间，使用AMUSE可在存在宏观受试者运动的情况下提高图像质量和扩散张量准确性。这些技术应有助于未来的高分辨率扩散成像。
