Gd-EOB-DTPA-enhanced MR imaging: prediction of hepatic fibrosis stages using liver contrast enhancement index and liver-to-spleen volumetric ratio.

PURPOSE: To develop and evaluate a quantitative parameter for staging hepatic fibrosis by contrast enhancement signal intensity and morphological measurements from gadoxetic acid (Gd-EOB-DTPA)-enhanced MR imaging.

MATERIALS AND METHODS: MR images were obtained in 93 patients; 75 patients had histopathologically proven hepatic fibrosis and 18 patients who had healthy livers were evaluated. The liver-to-muscle signal intensity ratio (SI(post) = SIliver/SImuscle), contrast enhancement index (CEI = SIpost/SIpre), and liver-to-spleen volumetric ratio (VR = Vliver/Vspleen) were evaluated for staging hepatic fibrosis.

RESULTS: VR was most strongly correlated with fibrosis stage (7.21; r = -0.83; P < 0.001). Sensitivity, specificity, and area under the ROC curve demonstrated by linear regression formula generated by VR and CEI in predicting fibrous scores were 100%, 73%, and 0.91, respectively, for the detection of hepatic fibrosis F1 or greater (≥ F1),100%, 87%, and 0.96 for ≥ F2, 74%, 98%, and 0.93 for ≥ F3 and 91%, 100%, and 0.97 for F4.

CONCLUSION: The liver-to-spleen volumetric ratio and contrast enhancement index were reliable biomarkers for the staging of hepatic fibrosis on Gd-EOB-DTPA-enhanced MR imaging.