PAEDIATRIC Hepatic ADC map as an adjunct to conventional abdominal MRI to evaluate hepatic fibrotic and clinical cirrhotic severity in biliary atresia patients Steven Shinn-Forng Peng 1 & Yung-Ming Jeng 2 & Wen-Ming Hsu 3 & Justin Cheng-Ta Yang 1,4 & Ming-Chih Ho 3 Received: 8 May 2014 /Revised: 11 March 2015 /Accepted: 12 March 2015 # European Society of Radiology 2015 Abstract Objectives Hepatic apparent diffusion coefficient (ADC) values and ADC-related indices were correlated with the Mayo risk score for primary biliary cirrhosis (MRSPBC) and METAVIR scores of liver specimens to determine the clinical and pathological significance of diffusion-weighted magnetic resonance imaging (DWMRI). Methods Thirty-two patients with biliary atresia (BA; mean age 461 days, range 11–4616 days) received magnetic reso- nance examinations from March 2009 to August 2013. A free- breathing DWMRI sequence was performed with the single- shot echo-planar imaging technique with b =0 and 500 s/mm 2 in all 32 BA patients and 24 controls. We used the ordinal logistic regression test and Spearman rank correlation test to analyse the relationships between the MRSPBC and META VIR fibrosis scores and right liver-to-psoas ADC ratios (LTPARs). Results BA patients had significantly lower LTPARs in both hepatic lobes than controls (p <0.01). Right LTPARs, showing moderate intraobserver agreement (intraclass correlation coefficient=0.736) and interobserver reliability (intraclass correlation coefficient=0.659), were negatively correlated with MRSPBC and METAVIR fibrosis scores (R 2 =0.398, p =0.024 and R 2 =0.628, p <0.001, respectively). Conclusion Right LTPARs may be used for long-term follow- up of cirrhosis severity in BA patients. Key Points • Hepatic ADC values by DWI correlates well with clinical/ pathologic fibrosis scores • Periodic, non-invasive, quantitative imaging follow-up of patients with biliary cirrhosis is feasible • Information on cirrhosis severity could help decide on man- agement options in children with BA • ADC values may be useful in this regard Keywords Biliary atresia . Biliary cirrhosis . Diffusion-weighted magnetic resonance imaging . Magnetic resonance imaging . Pathology Abbreviations ADC Apparent diffusion coefficient ALT Alanine transaminase ANOVA Analysis of variance AST Aspartate transaminase BA Biliary atresia CT Child–Turcotte DWMRI Diffusion-weighted magnetic resonance imaging ICC Intraclass correlation coefficient IVIM Intravoxel incoherent motion LTPAR Liver-to-psoas apparent diffusion coefficient ratio MRI Magnetic resonance imaging MRSPBC Mayo risk score for primary biliary cirrhosis ROC Receiver operating characteristic ROI Region of interest * Ming-Chih Ho steven0131@mail2000.com.tw 1 Department of Medical Imaging, Medical College and Hospital, National Taiwan University, Taipei, Taiwan 2 Department of Pathology, Medical College and Hospital, National Taiwan University, Taipei, Taiwan 3 Department of Surgery, Medical College and Hospital, National Taiwan University, 7 Chung-Shan South Road, Taipei 100, Taiwan Republic of China 4 Institute of Biomedical Engineering, College of Engineering and College of Medicine, National Taiwan University, Taipei, Taiwan Eur Radiol DOI 10.1007/s00330-015-3716-1