To the Editor.—We read with interest the article by Dr Neoptolemos and colleagues1 concerning the use of endoscopic retrograde cholangiopancreatography in the diagnosis and treatment of gallstone acute pancreatitis. The authors state that noninvasive imaging modalities, including ultrasonography and computed tomography, are of "dubious" value for detecting choledocholithiasis. We have found these modalities, especially computed tomography, to be quite useful in this regard. By using state-of-the-art equipment, fast scanners (≤2 s), and fine collimation (5 mm) scans, intraductal stones can be detected in up to 90% of cases.2,3 Improved ultrasound techniques, including scanning the intrapancreatic bile duct transversely with the patient upright, can increase the rate of sonographic detection to 89% and 70% for proximal and distal stones, respectively.4 The noninvasive imaging modalities can provide a fairly accurate screen for choledocholithiasis and should be considered before more invasive studies are undertaken.