Imaging pancreatobiliary ductal system with optical coherence tomography: A review

Figure 7 Optical coherence tomography image of a patient with a benign stricture. The three-layered structure of the biliary wall is recognizable (Color online). A-D shows images of malignant bile duct strictures. B: Disorganized layered structure with unidentifiable margins and a strongly heterogeneous back-scattering signal; C: Large, nonreflective areas in the intermediate layer suggesting the tumor vessels; D: Malignant stricture due to hilar metastases of an esophageal squamous carcinoma showing nonreflective areas and disorganized layer architecture[2].