Hepatobiliary disease is listed in the differential diagnosis of patients presenting to the emergency department with abdominal pain. Patients with right upper quadrant (RUQ) pain associated with fever, nausea, vomiting, and/or jaundice may have hepatobiliary disease as the cause and a bedside biliary ultrasound will assist in making this diagnosis.
Sonographic evaluation of the biliary system is a core emergency ultrasound application according to the 2008 American College of Emergency Physicians Policy on Emergency Ultrasound.
Clinical Indications for Performing a Biliary Ultrasound
The main indication for biliary emergency ultrasound is rapid identification of sonographic markers of acute cholecystitis.
Performing a Biliary Ultrasound
Anatomic landmarks and considerations. The liver is an intraperitoneal structure located in the RUQ of the abdomen. The liver is bordered superiorly by the diaphragm, inferomedially by the duodenum and head of the pancreas, and inferiorly by the gallbladder, hepatic flexure and ascending colon, and the superior pole of the right kidney. The gallbladder lies on the inferior surface of the liver between the right and left lobe of the liver. It is bordered inferiorly by the hepatic flexure and transverse colon and medially by the duodenum.
The liver has a characteristic sonographic appearance and serves as an echo-friendly window for imaging the gallbladder. The gallbladder appears as a cystic oval-shaped organ whose wall may contain normal anatomic variants such as folds, septations, and – when located at the fundus – a Phrygian cap. The main lobar fissure (MLF) appears to connect the gallbladder on long axis view to the portal vein and altogether gives a characteristic “exclamation point” appearance. The median hepatic vein divides the liver into right and left lobes and runs with the MLF. The hepatic artery and common bile duct (CBD) lie anterior to the portal vein, and the three together make the portal triad.