Non-invasive portography: a microbubble-induced three-dimensional sonogram for discriminating idiopathic portal hypertension from cirrhosis

Objectives: The aim of this prospective study was to elucidate the efficacy of contrast-enhanced three-dimensional (3D) ultrasound with Sonazoid (R) (GF Healthcare, Oslo, Norway) as a non-invasive tool to discriminate idiopathic portal hypertension (IPH) from cirrhosis by demonstration of portal vein structure. Methods: There were 16 patients: 11 with biopsy-proven cirrhosis and 5 with biopsy-proven IPH. Intrahepatic right portal vein images were taken by 3D ultrasound from 1 min after the injection of Sonazoid (0.0075 ml kg(-1)). Portal vein appearances were compared between 3D ultrasound and percutaneous transhepatic portography (PTP) by four independent reviewers. Sensitivity, specificity and area under the receiver operating characteristic curve (Az) of the images were used for the diagnosis of cirrhosis/IPH, and interimaging, inter-reviewer and interoperator agreement were examined. Results: Sensitivity, specificity and Az of PTP for the diagnosis of cirrhosis/IPH were 63.6%/100%, 100% and 0.9 (0.71-1.0) by Reviewer I and 90.9%/100%, 100% and 1.0 by Reviewer III, respectively. Similarly, sensitivity, specificity and Az of 3D ultrasound for diagnosis of cirrhosis/IPH were 54.5%/80%, 100% and 0.96 (0.84-1.0) by Reviewer II and 72.7%/80%, 100% and 0.97 (0.9-1.0) by Reviewer IV, respectively. Diagnostic agreement between PTP and 3D ultrasound was good between Reviewers I and II (kappa-0.793) and good between Reviewers III and IV (kappa=0.732). Inter-reviewer agreement was good between Reviewers I and III for PTP diagnosis (kappa=0.735), and good between Reviewers II and IV for 3D ultrasound diagnosis (kappa=0.792). Interoperator agreement of diagnostic results was good (kappa=0.740). Conclusion: Non-invasive visualisation of intrahepatic portal vein structure by contrast-enhanced 3D ultrasound with Sonazoid may have the potential to discriminate IPH from cirrhosis.