[Evaluation of early stage diffused liver lesions with MR functional diffusion-weighted imaging--an experimental study].
OBJECTIVE
To investigate the value of Diffusion-Weighted Imaging (DWI) in the diagnosis of early stage liver diffuse lesions.


METHODS
Diethylnitrosamine (DEN) was used to induce liver lesions in rats. Sequential DWI studies were performed on the livers from 1 to 14 weeks after DEN was administered through drinking water. Comparing studies with a blank control group was set and pathohistological examinations of the livers were performed.


RESULTS
No obvious routine MRI morphological change was found in either group during this period, but DWI demonstrated heterogeneous changes in the test group at the cirrhosis stage. There was no significant alteration of the apparent diffusion coefficient (ADC) value in the control group during this period (P > 0.05). The ADC values of the test group began to decline from the fifth week. Until the tenth week, the ADC value of the test group decreased drastically and when b = 300 s/mm2 statistic, the results showed an obvious difference between the two groups. There were also differences between the ADC values at the 10th, the 9th and the 1st weeks of the test group (P < 0.05). When b = 600 s/mm2 and 1000 s/mm2, significant differences were found after the sixth week between the two groups (P < 0.01). The main pathohistological liver change in the test group during the 1 to 4 week period after DEN was administered was swelling of hepatocytes; during the 5 to 8 week period it was fibrous tissues hyperplasia, and in the 9 to 14 week period it was cirrhotic nodule formation.


CONCLUSIONS
MR functional DWI could detect liver diffuse lesions earlier than conventional MR imaging. Measurement of ADC value may be of use in early diagnosis of liver diffuse diseases and for monitoring the changes of the lesions.
Guan
Sheng
S
Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
Zhao
Wei-dong
WD
Zhou
Kang-rong
KR
Peng
Wei-jun
WJ
Tang
Feng
F
Mao
Jian
J
Cao
Guang
G
Sun
Fei
F
D000818:Animals; D056486:Chemical and Drug Induced Liver Injury; D004052:Diethylnitrosamine; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D008107:Liver Diseases / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D004052:Diethylnitrosamine