Biloma

A biloma is an encapsulated collection of bile that accumulates outside the biliary system, typically in the peritoneal cavity or within the liver parenchyma. It most commonly occurs after liver surgery, gallbladder removal, or abdominal trauma that damages the bile ducts. On ultrasound, a biloma appears as a well-defined, anechoic or hypoechoic fluid collection, which can be difficult to distinguish from other types of fluid collections like abscesses or hematomas based on imaging alone. Ultrasound is useful for detecting bilomas and guiding percutaneous drainage procedures, while correlation with clinical history and sometimes fluid analysis helps confirm the diagnosis.