Diffusion MRI techniques, which rely on the Brownian motion of water molecules in tissues, can provide information about the functional environment of the lesion, in addition to the morphological information obtained from structural MRI. Reproducibility is an important prerequisite for the clinical application of these quantitative diffusion metrics.Therefore, the purpose of this study was to assess the impact of scan protocols and observers on the variability and reproducibility of quantitative diffusion metrics.

This prospective study was approved by the ethical committee of our institution, and the written informed consents were obtained from all volunteers. The workflow of the study is presented in Figure 1. [Fig 1]We screened 15 potential participants who volunteered to undergo brain MRI scans between June 2023 and August 2023. One participant was excluded due to artifacts from dental implants. Consequently, 14 healthy participants were included in the analysis.The participants underwent diffusion spectrum imaging with a 3.0-T scanner. The volunteers were repositioned among four...

There are 14 volunteers (7 men; median age, range, 28, 26–59 years) included in the study. Figure 2 is an example for quantitative diffusion metrics from four models. [Fig 2]The variability of quantitative diffusion metrics showed CV of 2.4%–68.2%, and QCD of 0.6%–48.2%, respectively. The reproducibility of scans using 20-channel coils with voxels of 2 * 2 * 2 mm3 and 3 * 3 * 3 mm3, respectively (ICC 0.03–0.84, CCC 0.03–0.84) was significantly worse than that of repeated scans using a 20-channel coil with...

Voxel size had a significant effect on the reproducibility of quantitative diffusion metrics. We suggest that variability and reproducibility assessments of quantitative diffusion metrics should be conducted prior to the implementation of one-stop diffusion MRI protocols in clinical practice.The complete study has been published in J Magn Reson Imaging [3].

J. Zhong: Board Member: Dr. Jingyu Zhong acknowledges his position as a member of the Musculoskeletal section of the Scientific Editorial Board of European Radiology. X. Liu: Nothing to disclose W. Lu: Nothing to disclose Y. Hu: Nothing to disclose H. Zhang: Nothing to disclose W. Yao: Nothing to disclose

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