Assessment of liver fibrosis by variable flip angle T1 mapping at 3.0T.
OBJECTIVE
To evaluate the possibility of using a variable flip angle (VFA) T1 mapping technique to diagnose liver fibrosis.


METHODS
Liver fibrosis was induced in rabbits by repetitive administration of carbon tetrachloride (CCl4 ). T1 -weighted magnetic resonance imaging (MRI) was performed in 29 animals (liver fibrosis, n = 18; control, n = 11) using a series of nonenhanced liver acquisition volume acceleration (LAVA) with VFAs at 3.0T. Hepatic T1 relaxation times were measured via regions of interest, which were correlated with subsequent histologic confirmation. The results of T1 mapping in assessment of liver fibrosis were compared with that of apparent diffusion coefficient (ADC) values.


RESULTS
The mean T1 relaxation time of the control group was the lowest (250.07 ± 88.12 msec), followed by the nonadvanced fibrosis group (387.83 ± 166.58 msec) and the advanced fibrosis group (496.90 ± 291.24 msec). T1 relaxation time measurements differed significantly between the liver fibrosis group and control group (P < 0.05), with a trend of increased mean T1 relaxation times as the fibrotic stage increased. Statistically significant differences were observed between the control group and the nonadvanced fibrosis group (P < 0.05), however with much overlap between the less severe stages. In discriminating between the control group and liver fibrosis group, stage F0-1 (control and stage F1) and stage F2-3, stage F0-2 (control and stage F1-2) and stage F3, area under the receiver operating characteristic (ROC) curves were 0.803 (cutoff value 273.01 msec), 0.712 (cutoff value 371.54 msec), and 0.696 (cutoff value 276.99 msec), respectively. No difference was found between T1 relaxation times and ADC values in assessment of liver fibrosis in our study.


CONCLUSIONS
VFA T1 mapping may become a noninvasive imaging tool for the diagnosis of liver fibrosis.
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Zhiming
Z
Li
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Jihong
J
Sun
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Xi
X
Hu
Life Science, GE Healthcare China, Beijing, China.
Ning
N
Huang
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Guocan
G
Han
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Lumin
L
Chen
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Yurong
Y
Zhou
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Weixian
W
Bai
Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.|Image-Guided Bio-Molecular Interventions Research, Department of Radiology, University of Washington School of Medicine, Seattle, Washington, USA.
Xiaoming
X
Yang
D000054:Acceleration; D000818:Animals; D002251:Carbon Tetrachloride / Q000737:chemistry; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D012372:ROC Curve; D011817:Rabbits; D015203:Reproducibility of Results
D003287:Contrast Media; D002251:Carbon Tetrachloride
T1 mapping; liver fibrosis; magnetic resonance imaging; variable flip angle