Ultrasonography of the acute abdomen.

During the past decade, noninvasive imaging has assumed an increasingly prominent role in the evaluation of patients who have acute abdominal conditions. Ultrasonography is often the initial diagnostic imaging modality used to examine patients who are clinically suspected of having acute cholecystitis, choledocholithiasis, and acute appendicitis. This article focuses on the clinical considerations and the ultrasonographic findings that relate to each of these conditions. In addition to describing the ultrasonographic appearances for each of these entities, this article also emphasizes useful scanning techniques that will provide optimal images.