Synopsis

Multi-parametric MR including MR elastography (MRE), IDEAL IQ and diffusion weighted image were performed in patients with chronic liver disease. Among them, 15 patients were treated with antiviral agents which could improve liver fibrosis. In patients who underwent antiviral treatment, liver stiffness measured by MRE after treatment was significantly decreased. Liver stiffness in non-treated group and other MR parameters in both groups were not significantly changed. In conclusion, MRE could be used for the response evaluation of antiviral therapy in patients with chronic hepatitis

Introduction

Along with the development of antiviral treatments, liver fibrosis has become a treatable disease if diagnosed early. Hence, it is necessary to diagnose liver fibrosis earlier and to evaluate the therapeutic effect. Liver biopsy is the golden standard methods for the diagnosis of liver fibrosis, but it is difficult to perform repeatedly, due to invasiveness. Recently, MR elastography (MRE) has been reported to be accurate for diagnosis liver fibrosis.^1-3 The purpose of this study was to investigate the feasibility of MRE as a monitoring tool in patients who underwent antiviral therapy

Methods

This study enrolled 24 patients (mean age, 56.2±11.0 years; male, 33.3%) who had chronic liver disease confirmed by liver biopsy. Of those patients, 15 received antiviral treatment (group A) and the remaining 9 received no treatment (group B). Multi-parametric MR were obtained in all patients before and after antiviral treatment in 3T MR system (Discovery 750w 3.0T, GE healthchare) with a 32-channel torso coil. MRI protocol includes IDEAL IQ, diffusion weighted image (DWI), and MRE. Proton density fat fraction (PDFF), R2* value, ADC value, and liver stiffness were compared between the two groups. All MR parameters were also compared before and after antiviral treatment in two groups. A P value less than 0.05 were considered as statistically significant.

Results

There were no significant difference in age (P=0.570) and sex (P>0.999) between group A (57.3±11.5 years old; 33.3%) and group B (54.6±10.5 years old; 33.3%). The interval between the pre-treatment MR and the post-treatment MR was 454.5 (standard deviation, ±102.1) days, and that between the pre-treatment MR and liver biopsy was 52.7 (±49.2) days. There was no difference in fibrosis stage between the two groups (P=0.782). In pretreatment MRI, all MR parameters were not significantly different between group A and group B (Figure 1). Compared to pretreatment, liver stiffness on MRE after antiviral treatment was significantly decreased in group A (4.2 kPa to 3.5 kPa, P=0.040), but there was no difference in group B (4.6 kPa to 3.9 kPa, P=0.076, Figure 2). PDFF, R2* and ADC were not significant different between before and after antiviral treatment in both groups (P>0.05)

Discussion

Antiviral therapy has been reported to improve liver fibrosis.⁴ Previous studies used fibroscan, one of the noninvasive methods, to measure changes in liver fibrosis.⁴ However, MRE has better diagnostic accuracy than fibroscan in liver fibrosis assessment.⁵ According to our results, liver stiffness decreased only in the antiviral treatment group, which suggested that MRE can be used as a non-invasive diagnostic tool for evaluating treatment response of antiviral agents.

Conclusion

MRE might be used for the evaluation of treatment response of antiviral agents in patients with chronic hepatitis

Acknowledgements

References

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5.Xiao H, Shi M, Xie Y, Chi X. Comparison of diagnostic accuracy of magnetic resonance elastography and Fibroscan for detecting liver fibrosis in chronic hepatitis B patients: A systematic review and meta-analysis. PLoS One 2017;12:e0186660.