Sonography of acute pancreatitis: prevalence of findings and pictorial essay.

The purpose of this article is to describe the sonographic findings of acute pancreatitis, establish their individual prevalence, and illustrate the sonographic findings in acute pancreatitis. Prevalence of findings was determined by reviewing abdominal sonograms in 48 adult patients, derived from 71 consecutive patients who had been scanned using our standard abdominal protocol, which routinely evaluates the pancreas and peripancreatic regions. The mean anteroposterior measurement of the pancreatic body at the level of the superior mesenteric artery was 21.1 mm +/- 6.4 mm with a range of 12 to 45. Decreased pancreatic echogenicity compared with the liver was noted in 21 patients (44%). A heterogeneous echo pattern was detected in 27 patients (56%). Focal intrapancreatic regions of abnormal echogenicity were seen in 11 of 48 patients (23%). Focal masses were seen in 8 of 48 patients (17%). Hypoechoic peripancreatic areas of inflammation were seen in 29 of 48 patients (60%) and acute peripancreatic fluid collections were seen in 10 of 48 patients (21%). In this study, sonography revealed abnormalities in 45 of 48 patients (91.7%). Diffuse decreased echogenicity, focal contour, and focal echogenicity changes within the pancreas are associated with extrapancreatic disease.