Apparent diffusion coefficient value of hepatic fibrosis and inflammation in children with chronic hepatitis.

ABSTRACT

PURPOSE: This study was done to prospectively evaluate the usefulness of apparent diffusion coefficient (ADC) in the diagnosis and grading of hepatic fibrosis and inflammation in children with chronic hepatitis. MATERIALS AND METHODS: Institutional Review Board approval was obtained. This prospective study was carried out on 50 children with chronic hepatitis (mean age 8.3 ± 3.2 years; 33 boys and 17 girls) and 20 age- and sex-matched healthy control children. The children underwent diffusion-weighted magnetic resonance imaging of the liver. The ADC value of the liver was calculated. The hepatic fibrosis stages (F1-F6) and necroinflammatory activity grades (A1-A4) were calculated. The ADC values of different stages of hepatic fibrosis and grades of necroinflammatory activity were calculated. RESULTS: The mean ADC value of the liver parenchyma was 1.53 ± 0.17 × 10(-3) mm(2)/s in children with chronic hepatitis and 1.74 ± 0.16 × 10(-3) mm(2)/s in controls. The ADC value was significantly lower in children with hepatic fibrosis compared to controls (p = 0.001). There was a significant difference (p = 0.001) in ADC between mild (F1-F3) and advanced (F4-F6) stages of fibrosis. There was a significant difference (p = 0.004) in ADC between mild (A1-A2) and advanced (A3-A4) grades of necroinflammation. The cut-off ADC values used to differentiate mild from advanced fibrosis and necroinflammation were 1.62 and 1.64 mm(2)/s with an area under the curve of 0.898 and 0.807, respectively. The ADC value negatively correlated with stages of hepatic fibrosis (r = -0.799, p = 0.001) and necroinflammatory activity grade (r = -0.468, p = 0.001). CONCLUSIONS: We conclude that ADC value is an effective noninvasive parameter for the diagnosis and grading of hepatic fibrosis and inflammation in children with chronic hepatitis.