Multimodal endoscopic evaluation of indeterminate biliary strictures

Indeterminate biliary strictures, those whose etiology remains unclear after initial workup, require further endoscopic evaluation. The biliary endoscopist may utilize both endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) in the evaluation of indeterminate strictures, maximizing the relative strengths of both procedures. Techniques to optimize ERCP yield, including brush cytology, forceps biopsies, needle aspiration and direct cholangioscopy, are described in this article. Ultrasound evaluation, intraductal as well as EUS with fine needle aspiration, may also be used in concert with ERCP and these techniques are also described. The goal of endoscopic evaluation is the identification of malignant lesions at a resectable stage.