Objectives: The purpose of this study was to evaluate to which degree investment of acquisition time in more encoding directions leads to better image quality (IQ) and what influence the number of encoding directions and the choice of b-values have on renal diffusion tensor imaging(DTI) parameters. Material and Methods: Eight healthy volunteers (32.3 y ± 5.1 y) consented to an examination in a 1.5T whole-body MR scanner. Coronal DTI data sets of the kidneys were acquired with systematic variation of b-values (50, 150, 300, 500, and 700 s/mm2 ) and number of diffusion-encoding directions (6, 15, and 32) using a respiratory-triggered echo-planar sequence (TR/TE 1500 ms/67 ms, matrix size 128 × 128). Additionally, two data sets with more than two b-values were acquired (0, 150, and 300 s/mm2 and all six b-values). Parametrical maps were calculated on a pixel-by-pixel basis. Image quality was determined with a reader score. Results: Best IQ was visually assessed for images acquired with 15 and 32 encoding directions, whereas images acquired with six directions had significantly lower IQ ratings. Image quality, fractional anisotropy, and mean diffusivity only varied insignificantly for b-values between 300 and 500 s/mm2. In the renal medulla fractional anisotropy (FA) values between 0.43 and 0.46 and mean diffusivity (MD) values between 1.8-2.1 × 10-3 mm2/s were observed. In the renal cortex, the corresponding ranges were 0.24-0.25 (FA) a 2.2-2.8 × 10-3 mm2 /s (MD). Including b-values below 300 s/mm2 , notably higher MD values were observed, while FA remained constant. Susceptibility artifacts were more prominent in FA maps than in MD maps. Conclusion: In DTI of the kidneys at 1.5T, the best compromise between acquisition time and resulting image quality seems the application of 15 encoding directions with b-values between 300 and 500 s/mm2. Including lower b-values allows for assessment of fast diffusing spin components.
Wen-jun Fan, Tao Ren, Qiong Li, Pan-li Zuo, Miao-miao Long, Chun-bai Mo, Li-hua Chen, Li-xiang Huang and Wen Shen (2016) Assessment of renal allograft function early after transplantation with isotropic resolution diffusion tensor imaging. Eur Radiol26(2):567. doi: 10.1007/s00330-015-3841-x
Sophie van Baalen, Alexander Leemans, Pieter Dik, Marc R. Lilien, Bennie ten Haken and Martijn Froeling (2017) Intravoxel incoherent motion modeling in the kidneys: Comparison of mono-, bi-, and triexponential fit. J. Magn. Reson. Imaging46(1):228. doi: 10.1002/jmri.25519
Qian Ji, Zhi Qiang Chu, Tao Ren, Shi Chao Xu, Long Jiang Zhang, Wen Shen and Guang Ming Lu (2017) Multiparametric functional magnetic resonance imaging for evaluation of hepatic warm ischemia-reperfusion injury in a rabbit model. BMC Gastroenterol17(1):. doi: 10.1186/s12876-017-0720-8
Xinghui Li, Qi Liang, Ling Zhuang, Xiaoming Zhang, Tianwu Chen, Liangjun Li, Jun Liu, Horea Calimente, Yinan Wei, Jiani Hu and Quan Jiang (2015) Preliminary Study of MR Diffusion Tensor Imaging of the Liver for the Diagnosis of Hepatocellular Carcinoma. PLoS ONE10(8):e0135568. doi: 10.1371/journal.pone.0135568
B.F. Kjølby, A.R. Khan, A. Chuhutin, L. Pedersen, J.B. Jensen, S. Jakobsen, D. Zeidler, R. Sangill, J.R. Nyengaard, S.N. Jespersen and B. Hansen (2016) Fast diffusion kurtosis imaging of fibrotic mouse kidneys. NMR Biomed.29(12):1709. doi: 10.1002/nbm.3623
Sheung-Fat Ko, Hon-Kan Yip, Yen-Yi Zhen, Chi-Chih Hung, Chen-Chang Lee, Chung-Cheng Huang, Shu-Hang Ng, Yi-Ling Chen and Jui-Wei Lin (2019) Renal Damages in Deoxycorticosterone Acetate–Salt Hypertensive Rats: Assessment with Diffusion Tensor Imaging and T2-mapping. Mol Imaging Biol:. doi: 10.1007/s11307-019-01364-z
Mehmet Burak Özkan, Robert Marterer, Sebastian Tscheuner, Utku Mahir Yildirim and Elif Ozkan (2016) The role of kidney diffusion tensor magnetic resonance imaging in children. The Egyptian Journal of Radiology and Nuclear Medicine47(4):1599. doi: 10.1016/j.ejrnm.2016.08.015
Stefano Palmucci, Giuseppina Cappello, Giancarlo Attinà, Pietro Valerio Foti, Rita Olivia Anna Siverino, Federica Roccasalva, Marina Piccoli, Nunziata Sinagra, Pietro Milone, Massimiliano Veroux and Giovanni Carlo Ettorre (2015) Diffusion weighted imaging and diffusion tensor imaging in the evaluation of transplanted kidneys. European Journal of Radiology Open2:71. doi: 10.1016/j.ejro.2015.05.001
Qiong Ye, Zhongwei Chen, Youfan Zhao, Zhenhua Zhang, Haiwei Miao, Qinqin Xiao, Meihao Wang and Jiance Li (2016) Initial experience of generalized intravoxel incoherent motion imaging and diffusion tensor imaging (GIVIM-DTI) in healthy subjects. J. Magn. Reson. Imaging44(3):732. doi: 10.1002/jmri.25262
Xiang-Ying Li, Jian-Qiang Chen, Yi-Kai Xu and Xiang-Jun Han (2017) The relationship between fractional anisotropy value and tumor microarchitecture in late-stage rat glioma. Asian Pacific Journal of Tropical Medicine10(6):607. doi: 10.1016/j.apjtm.2017.06.011
Yu-Ting Wang, Ying-Chun Li, Wei-Fang Kong, Long-Lin Yin and Hong Pu (2017) Diffusion tensor imaging beyond brains: Applications in abdominal and pelvic organs. WJMA5(3):71. doi: 10.13105/wjma.v5.i3.71
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