Application Value of Magnetic Resonance Perfusion Imaging in the Early Diagnosis of Rat Hepatic Fibrosis

Abstract

Objective. To assess the application value of perfusion-weighted imaging (PWI) in early diagnosis, quantitation, and hepatic fibrosis staging by analyzing the related parameters in hepatic fibrosis. Methods. A total of 60 rats were randomly divided into the hepatic fibrosis and control groups, and carbon tetrachloride (CCL4) was used to establish the liver fibrosis model. All rats underwent PWI examination, and the trend of the time-signal intensity curve (TIC, automatically generated by the software) was observed. Also, the perfusion parameters, maximum signal reduction ratio (SRRmax), time to peak (TTP), and mean transit time (MTT), were analyzed and compared with pathological staging. Results. The TIC curve was characterized by slow wash-in and wash-out with a low and wide peak. The PWI perfusion parameters were statistically significant in specific groups (P<0.05): SRRmax values (control group and F3, F4), TTP, and MTT values (control group and F2–F4, F1 and F3, F1 and F4, and F2 and F4 in addition to TTP values for F1 and F2). Pearson’s correlation analysis showed a negative correlation of SRRmax with hepatic fibrosis stage (r = −0.439, P<0.05), while TTP and MTT values were positively correlated with hepatic fibrosis stage (TTP, r = 0.798; MTT, r = 0.647; all P<0.001). Conclusions. PWI perfusion parameters reflect the degree of hepatic fibrosis, especially TTP and MTT, and PWI is recommended for the early diagnosis of liver fibrosis for timely intervention and treatment of the disease and delaying its progression.

Comparison of MR-PWI quantitative and semi-quantitative parameters for the evaluation of liver fibrosis

“…These pathological changes are aggravated with the progression of liver fibrosis; and thus, TPP was found to gradually increase and show significant differences in each stage of liver fibrosis. Our results were consistent with the study using rat liver fibrosis model conducted by Fan et al [ 42 ]. They showed that TTP and mean transit time values were positively correlated with hepatic fibrosis stage via Pearson's correlation analysis.…”

“…Our results indicated that TTP is the most important MR-PWI semi-quantitative parameter for the diagnosis of liver fibrosis with a Youden index of 0.85. Previous study showed that PWI perfusion parameters, especially TTP and mean transit time reflected the degree of hepatic fibrosis [ 42 ]. Since hepatic sinus capillarization and collagen depositions around the hepatic sinus and extravascular space can lead to a prolonged strengthening peak time of contrast agents, more severe liver fibrosis resulted in a longer TTP with a positive correlation.…”

“…The developed diffusion kurtosis imaging based on DWI has been conducive to identify the stages of liver fibrosis [37,38], while the DWI evaluation of liver fibrosis has not achieved a widely recognized diagnostic standard. In contrast, MR-PWI as a non-invasive functional imaging technology based on hemodynamics has become breakthroughs in the field of imaging medicine, making it possible for the early diagnosis of liver fibrosis before the morphological changes of the liver tissue [39][40][41][42]. More importantly, MR-PWI has the advantage of no radiation damage, and therefore, shows great promise for clinical applications.…”

The roles and mechanisms of hypoxia in liver fibrosis

“…Hepatic sinusoid is the narrowest vascular structure within the liver and is the principal site of blood flow regulation. Hepatic sinusoidal capillarization, characterized by gradually shrinking fenestrae on the surface of liver sinusoidal endothelial cells (LSECs) and forming of an organized basement membrane, is an initial pathologic change associated with liver fibrosis [ 24 ]. Capillary sinusitis is a gradual process.…”

Noninvasive imaging of hepatic dysfunction: A state-of-the-art review

“…Besides, liver fibrosis can result in changes in hepatic microcirculation and perfusion. Fan et al [ 84 ] found that MR perfusion parameters, time to peak, and mean transit time in particular could reflect the degree of liver fibrosis. Similarly, Yoon et al [ 85 ] also found that portal blood flow was significantly lower in clinically significant hepatic fibrosis and that mean transit time and extracellular volume increased in cirrhosis.…”