Experimental Evaluation of Accelerated T1rho Relaxation Quantification in Human Liver Using Limited Spin-Lock Times.
10.3348/kjr.2012.13.6.736
- Author:
Feng ZHAO
1
;
Min DENG
;
Jing YUAN
;
Gao Jun TENG
;
Anil T AHUJA
;
Yi Xiang J WANG
Author Information
1. Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China. yixiang_wang@cuhk.edu.hk
- Publication Type:Original Article ; Comparative Study ; Evaluation Studies ; Research Support, Non-U.S. Gov't
- Keywords:
Magnetic resonance imaging;
Liver;
T1rho;
Spin-lock time
- MeSH:
Adult;
Eating;
Echo-Planar Imaging/*methods;
Fasting;
Female;
Humans;
Liver/*anatomy & histology;
Magnetic Resonance Imaging/*methods;
Male;
Young Adult
- From:Korean Journal of Radiology
2012;13(6):736-742
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: It was reported lately that to obtain consistent liver T1rho measurement, at 3T MRI using six spin-lock times (SLTs), is feasible. In this study, the feasibility of using three or two SLT points to measure liver T1rho relaxation time was explored. MATERIALS AND METHODS: Seventeen healthy volunteers underwent 36 examinations. Three representative axial slices were selected to cut through the upper, middle, and lower liver. A rotary echo spin-lock pulse was implemented in a 2D fast field echo sequence. Spin-lock frequency was 500 Hz and the spin-lock times of 1, 10, 20, 30, 40, and 50 milliseconds (ms) were used for T1rho mapping. T1rho maps were constructed by using all 6 SLT points, three SLT points of 1, 20, and 50 ms, or two SLTs of 1 and 50 ms, respectively. Intra-class correlation coefficient (ICC) and Bland and Altman plot were used to assess the measurement agreement. RESULTS: Two examinations were excluded, due to motion artifact at the SLT of 50 ms. With the remaining 34 examinations, the ICC for 6-SLT vs. 3-SLT T1rho measurements was 0.922, while the ICC for 6-SLT vs. 2-SLT T1rho measurement was 0.756. The Bland and Altman analysis showed a mean difference of 0.19 (95% limits of agreement: -1.34, 1.73) for 6-SLT vs. 3-SLT T1rho measurement, and the mean difference of 0.89 (95% limits of agreement: -1.67, 3.45) for 6-SLT vs. 2-SLT T1rho measurement. The scan re-scan reproducibility ICC (n = 11 subjects) was 0.755, 0.727, and 0.528 for 6-SLT measurement, 3-SLT measurement, and 2-SLT measurement, respectively. CONCLUSION: Adopting 3 SLTs of 1, 20, and 50 ms can be an acceptable alternative for the liver T1rho measurement, while 2 SLTs of 1 and 50 ms do not provide reliable measurement.
