Dear Editor,

Many image techniques (IT) allow the confirmation or exclusion of the presence of common bile duct stones (CBDS). An abdominal ultrasound and liver function test are performed first. Additional techniques should include magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS); both are recommended in medium risk CBDS patients (sensitivity 93-95% and specificity 96-97%) ^1,2. As experts argue, IT must be less invasive, accurate and cost-effective. Some endoscopists consider that they must provide an added value and not just confirm the presence of CBDS. The technique should allow adequate information to be obtained previous to the endoscopic retrograde cholangiopancreatography (ERCP) to optimize patient management.

EUS is recommended in specific situations such as the presence of a pacemaker, metal valves and intracranial clips, claustrophobia, morbid obesity, critical patients in the intensive care unit and patients with a negative MRCP and a moderate-high suspicion of CBDS ^1,2. MRCP is widely available and non-invasive, sedation is not required, intrahepatic ducts can be explored and is useful in patients with a modified gastroduodenal anatomy. In addition, images can be stored and reviewed after the procedure and the procedure is also cost-effective ^1,2,3.