Intraductal ultrasound substantiates diagnostics of bile duct strictures of uncertain etiology

Figure 1 An exemplary benign and malignant bile duct stenosis. A: Benign bile duct stricture showing a homogeneous hyperechoic lesion with smooth margins (arrow); B: Malignant stricture showing bile duct wall thickening and irregular margins (arrow).

Figure 2 Flow chart showing the enrollment of study patients and distribution based on intraductal ultrasound diagnosis. IDUS: Intraductal ultrasound.

Figure 3 Suggested algorithm for the evaluation of bile duct strictures of uncertain etiology. US: Ultrasound; MDCT: Multidetector computed tomography; EUS: Endoscopic ultrasound; MRCP: Magnetic resonance cholangio-pancreatography; CBD: Common bile duct; IDUS: Intraductal ultrasound; CEUS: Contrast enhanced ultrasound; EUS-FNA: Endoscopic ultrasound with fine needle aspiration; CT: Computed tomography.