Robin Bülow MD, Presenter: Nothing to Disclose

Birger Mensel MD, Abstract Co-Author: Nothing to Disclose

Peter Meffert, Abstract Co-Author: Nothing to Disclose

Matthias Evert, Abstract Co-Author: Nothing to Disclose

Scott Brian Reeder MD, PhD, Abstract Co-Author: Nothing to Disclose

Diego Hernando, Abstract Co-Author: Nothing to Disclose

Norbert Hosten MD, Abstract Co-Author: Nothing to Disclose

Ralf Puls MD, Abstract Co-Author: Nothing to Disclose

Jens Kühn, Abstract Co-Author: Nothing to Disclose

To investigate the robustness of diffusion weighted magnetic resonance imaging (DW-MRI) for quantification of liver fibrosis/cirrhosis in the presence of fat and iron.

95 patients, including 48 men and 47 women, aged 57.0±14.2 years underwent a clinically indicated liver biopsy. 96 samples were histologically staged for liver fibrosis/cirrhosis (0-no fibrosis (Ishak 0), 1-little/moderate fibrosis (Ishak 1-4), 2-incomplete/complete cirrhosis (Ishak 5-6)), and graded for hepatic iron (0-no,1-low,2-moderate,3-high iron) and for hepatic steatosis. 72 hours after biopsy, navigator-triggered DW-MRI using b-values of 50/400/800s/mm2 was performed in a 1.5T system (Avanto, Siemens). Region-of-interest based measurements of calculated ADC were analyzed. ADC values were correlated with fibrosis/cirrhosis stage, steatosis grade, and iron grade using a linear regression.

ADC did not correlate with fibrosis/cirrhosis, neither in the overall group (n=96;R2=0.38;p=0.17), nor in the sub-group without liver iron and steatosis (n=40; R2=0.01;p=0.75). ADC decreased significantly with steatosis grade in cases without iron and fibrosis/cirrhosis (n=42;R2=0.28;ß=-5.3;p<0.001). Liver iron was correlated modestly with ADC in patients without fibrosis/cirrhosis and steatosis (n=33;R2=0.29;p=0.04), whereas high iron concentrations were associated with low ADC values (group3;β=-489;p=0.005;reference:group0) but intermediate levels were not (group1/group2:p=0.93/p=0.54;reference:group0).

DW-MRI does not adequately discriminate the fibrosis/cirrhosis. ADC decreases significantly in patients with hepatic steatosis and high hepatic iron content. This may be due to a real change in water diffusion or from residual fat signal in steatotic livers. Changes in ADC from iron overload are likely due to signal decay and noise floor effects in the fitting with severe iron overload.

DW-MRI does not adequately discriminate the liver fibrosis/cirrhosis.

Bülow, R, Mensel, B, Meffert, P, Evert, M, Reeder, S, Hernando, D, Hosten, N, Puls, R, Kühn, J, Robustness of Diffusion Weighted Magnetic Resonance Imaging for Quantification of Liver Fibrosis: Effects of Liver Steatosis and Iron.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12043596.html