Diseases of bile duct.

Diseases of the bile duct encompass a spectrum of disorders ranging from benign obstructive conditions to malignant neoplasms, representing a significant cause of hepatobiliary morbidity. This article reviews the pathophysiology, clinical presentation, and diagnostic challenges of major biliary diseases, with a primary focus on choledocholithiasis (common bile duct stones). It critically examines the indications, diagnostic accuracy, therapeutic capabilities, and limitations of the three principal modalities used in biliary pathologies: Endoscopic Retrograde Cholangiopancreatography (ERCP), Magnetic Resonance Cholangiopancreatography (MRCP), and Percutaneous Transhepatic Cholangiography (PTC). Following the IMRAD structure, this review synthesizes current literature to provide a comprehensive overview, emphasizing the evolution of a multimodal, risk-stratified approach where MRCP serves as a non-invasive diagnostic gatekeeper, ERCP as the predominant therapeutic tool, and PTC as a crucial rescue strategy in complex cases.