Revealing Impaired Blood Supply to the Bile Ducts on Contrast-Enhanced Ultrasound: A Novel Diagnosis Method to Ischemic-Type Biliary Lesions After Orthotropic Liver Transplantation

Ischemic-type biliary lesions (ITBLs) are a major source of morbidity and mortality after orthotropic liver transplantation (OLT). The study determines diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in diagnosing ITBLs. Nine healthy volunteers, six OLT recipients without complications, 36 OLT patients with complications (12 without ITBLs and 24 with ITBLs) underwent CEUS. Two radiologists reviewed the sonograms of the hilar bile duct wall and established specific criteria used to detect ITBLs. Next, the sonograms of six OLT recipients without complications and 36 patients with complications (12 without ITBLs and 24 with ITBLs) were retrospectively reviewed by two other independent, blinded radiologists. The sensitivity, specificity and accuracy of CEUS were evaluated. The main feature differentiating ITBLs from three other groups was non- or hypo-enhancement of the hilar bile duct wall in arterial phase (all p < 0.05), which was selected as the primary criterion for subsequent study. The sensitivity, specificity and accuracy were 66.7%, 88.9% and 76.2% for reader 1 and 62.5%, 88.9% and 73.8% for reader 2, respectively. A good interobserver agreement (κ = 0.85) was achieved. In this study, CEUS shows promise of detection of ITBLs by revealing impaired blood supply to the bile ducts, but more studies will be needed to establish its usefulness.