Primary Research Of Acoustic Radiation Force Impulse Technique In The Assessment Of Nonalcoholic Fatty Liver Disease

Objectives: To establish a model of nonalcoholic fatty liver disease(NAFLD) rats fedwith high fat diet and carbon tetrachloride. To investigate acoustic radiation forceimpulse technique in the noninvasive prediction of nonalcoholic fatty liver disease.Methods: Sixty male SD rats were randomly divided into normal control group (C1group) fed with normal food for4weeks, model group fed with high fat diet and carbontetrachloride by gastric intubation (M1group) for4weeks, normal control group (C2group) fed with normal food for8weeks, model group fed with high fat diet and carbontetrachloride by gastric intubation (M2group) for8weeks, normal control group (C1group) fed with normal food for12weeks, model group fed with high fat diet andcarbon tetrachloride by gastric intubation (M3group) for12weeks. C1group and M1group were sacrificed at the end of the4thweek. C2group and M2group weresacrificed at the end of the8thweek. C3group and M3group were sacrificed at the endof the12thweek. Check on the liver index (the ratio of wet weight of liver to bodyweight) of rats when they were sacrificed. Check on the weight of rats weekly. All therats’ liver were examined using acoustic radiation force Impulse (ARFI) technique. Thelevels of serum TC, TG, AST, ALT were measured by biochemical method. Liverhistopathologic evaluation was performed by hematoxylin-eosin staining.Results:(1) The increased body weight between M1group and C1group had nosignificant difference (p＞0.05). The liver index was higher in M1group than in C1group(p<0.05). The body weight was higher in M2group than in C2group and M1group (p<0.05). The liver index was increased in M2group than in C2group and M1group (p<0.05). The body weight was higher in M3group than in C3group, M1groupand M2group (p<0.05). The liver index was higher in M3group than in C3group andM1group (p<0.05). There was no significant difference between the M2group and M3 group’ liver index (p＞0.05).(2) The levels of serum TC, TG, AST and ALT were significantly higher in M groupthan in C group (p<0.05). The level of serum TC, TG, AST and ALT in M2group werehigher than in M1group (p<0.05). The level of serum TC, TG, AST and ALT in M3group were higher than in M1group and M2group (p<0.05).(3) The hepatic pathology of M1group was steatohepatitis, the success rates was100%;The hepatic pathology of M2group was fibrosis, the success rates was100%; Thehepatic pathology of M3group was cirrhosis, the success rates was75%.(4) The integration of fatty change, histologic activity scores of inflammatory andfibrosis score were higher in M group than in C group (p<0.05). The integration of fattychange, histologic activity scores of inflammatory and fibrosis score were higher overtime (p<0.05).(5) There was no significant difference of the liver shear wave velocity among C1group, C2group and C3group. There was no significant difference of the liver shearwave velocity between M1group and C1group (p＞0.05). The liver shear wavevelocity is intensified in M2group than in C2group and M1group (p<0.05). The livershear wave velocity is intensified in M3group than in C3group, M1group and M2group (p<0.05).Conclusions: The rat model of NAFLD can be established successfully by feedingwith high fat diet and carbon tetrachloride. Acoustic radiation force impulse imagingtechnology could used in the diagnosis of liver fibrosis and cirrhosis.