This patient presented with right upper quadrant/epigastric pain and tenderness, vomiting and raised inflammatory markers. Although the liver function tests were within normal ranges, ultrasound demonstrated a number of features in keeping with acute cholecystitis (thickened gallbladder wall, pericholecystic fluid) as well as potential cause (large calculus in the gallbladder neck) and some potential complications (biliary dilatation). 

The patient proceeded to MRCP to further characterize this and excluded any ductal stones. MRCP also cleared pancreatic duct involvement, and highlighted the low medial insertion of the cystic duct which is a common normal variant of biliary anatomy but important when considering surgical resection.