Chou Ming-Chung, Ko Cheng-Wen, Chiu Yu-Hsien, Chung Hsiao-Wen, Lai Ping-Hong
From the Departments of *Medical Imaging and Radiological Sciences, and †Healthcare Administration and Medical Informatics, Kaohsiung Medical University; ‡Department of Medical Research, Kaohsiung Medical University Hospital; §Department of Computer Science and Engineering, National Sun Yat-sen University, Kaohsiung; ∥Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei; ¶Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung; and #Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
J Comput Assist Tomogr. 2017 Nov/Dec;41(6):868-876. doi: 10.1097/RCT.0000000000000621.
Diffusion kurtosis imaging (DKI) has been widely used to characterize brain tissue alterations. Diffusion-weighting factor or b value plays an important role in the measurement of rapid DKI and may have influential effects on them. The purpose of this study was to investigate the effects of b value on rapid DKI indices in normal and acute ischemic brain tissues.
This study enrolled 10 healthy subjects and 4 acute ischemic stroke patients. Three repeated DKI data with 6 high b values (500, 750, 1000, 1500, 2000, 3000 s/mm) were acquired from healthy subjects, whereas nonrepeated DKI data with 3 high b values (1000, 2000, 3000 s/mm) were acquired from ischemic stroke patients. The DKI datasets were decomposed into several rapid DKI datasets consisting of 1 b0 and 2 high b values for comparisons.
The results showed that b value significantly impacted the reproducibility and accuracy of DKI indices. The comparisons demonstrated that DKI with b = (0, 1000, 3000) s/mm exhibited more reproducible and accurate DKI indices than other DKI datasets in normal brain tissues, and similar results were noticed in acute ischemic brain tissue.
We concluded that b value significantly impacted the quantification of DKI indices in both normal and acute ischemic brain tissues.
扩散峰度成像（DKI）已被广泛用于表征脑组织改变。扩散加权因子或b值在快速DKI测量中起重要作用，并且可能对其产生影响。本研究的目的是探讨b值对正常和急性缺血性脑组织中快速DKI指数的影响。
本研究纳入了10名健康受试者和4名急性缺血性中风患者。从健康受试者获取了具有6个高b值（500、750、1000、1500、2000、3000 s/mm²）的三次重复DKI数据，而从缺血性中风患者获取了具有3个高b值（1000、2000、3000 s/mm²）的非重复DKI数据。将DKI数据集分解为几个由1个b0和2个高b值组成的快速DKI数据集进行比较。
结果表明，b值显著影响DKI指数的可重复性和准确性。比较表明，在正常脑组织中，b =（0, 1000, 3000）s/mm²的DKI比其他DKI数据集表现出更高的可重复性和更准确的DKI指数，在急性缺血性脑组织中也观察到类似结果。
我们得出结论，b值在正常和急性缺血性脑组织中均显著影响DKI指数的量化。
