How I Do It 221This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited.

The biliary system plays a vital role in maintaining the physiologic functions of the human body; therefore, biliary obstruction requires prompt diagnosis to prevent further complications and decrease mortality. The vast array of benign and malignant etiologies that cause biliary obstruction make diagnostic and therapeutic decision-making challenging. Ultrasound is often the first diagnostic modality utilized. It is safe, non-invasive, and quick to obtain, but lacks the ability to diagnose the more ominous causes of biliary obstruction. Additional modalities to evaluate the biliary tree include CT, MRI, MRC, MRCP, ERCP, and PTC. This review outlines the importance of the biliary system, provides the clinical presentation of biliary obstruction, and examines the available imaging and treatment modalities and when to appropriately use them.