[Comparative study on clinical and pathological changes of liver fibrosis with diffusion-weighted imaging].
OBJECTIVE
To evaluate the clinical practical value of apparent diffusion coefficient (ADC) measurements based on diffusion-weighted MR imaging (DWI) for quantification of liver fibrosis and inflammation for hepatitis viral infection.


METHODS
Diffusion-weighted MRI with parallel imaging was prospectively performed on 85 patients with chronic hepatitis and on 22 healthy volunteers within a single breath-hold using a single-shot spin-echo echo-planar sequence at b values of 100, 300, 500, 800 and 1000 s/mm2 respectively. ADC values of liver were measured with five different b values. The inflammation grades and fibrosis stages were evaluated histologically by biopsy. One-way analysis of variance and Spearman' s rank correlation test were used for statistical analysis. Receiver operating characteristics analysis was used to assess the performance of ADC in predicting the presence of stage > or = 2 and stage > or = 3 hepatic fibrosis, and grade > or = 1 hepatic inflammation.


RESULTS
There was moderate negative correlation between hepatic ADC values and fibrosis stage. And the best correlation was obtained for a b value of 800 s/mm2 (r = -0.697, P = 0. 000). At all b values there was a significant decrease in hepatic ADC in patients with stage < or = 1 versus stage > or = 2 fibrosis and stage < or = 2 versus stage > or = 3 fibrosis (P < 0.05). Hepatic ADC was a significant predictor of stage > or = 2 and > or = 3 fibrosis. The areas under the curve were 0.909 vs 0.917, sensitivity 76.6% vs 80.0% and specificity 88.3% vs 91.5% (ADC with a b value of 800 s/mm2, 1.26 x 10(-3) mm2/s or less and 1.19 x 10(-3) mm2/s or less). There was weak to moderate negative correlation between ADCs and inflammation grade. Hepatic ADC was a significant predictor of grade > 1 inflammation with an area under the curve of 0.781, sensitivity of 60.0% and specificity of 86.4% (ADC with a b value of 500 s/mm2, 1.54 x 10(-3) mm2/s or less).


CONCLUSIONS
The DWI measurement of hepatic ADC can be used to quantify liver fibrosis and inflammation. It will be a new approach for early diagnosis and therapeutic follow-up of hepatic fibrosis.
Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
Mei-Ling
ML
Zhou
Fu-Hua
FH
Yan
Peng-Ju
PJ
Xu
Cai-Zhong
CZ
Chen
Ji-Zhang
JZ
Shen
Ren-Chen
RC
Li
Yuan
Y
Ji
Jian-Ying
JY
Shi
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006521:Hepatitis, Chronic / Q000473:pathology*; D006801:Humans; D008103:Liver Cirrhosis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult