Sonography of the scrotum: from appendages to scrotolithiasis.

In this pictorial essay, we review and discuss the varying morphologic characteristics of scrotal appendages and calculi. Characteristic sonograms obtained from patients with coexisting hydrocele are presented, and recent literature is included. Hydrocele greatly facilitates the imaging of these intrascrotal structures, as it acts as a "water path". On the one hand, torsion of a scrotal appendage should always be included in the differential diagnosis of acute scrotum, especially in children. On the other hand, scrotolithiasis may occasionally cause mild discomfort. As a consequence, and given the widespread use of sonography for the evaluation of both acute and chronic conditions of the scrotum, radiologists should be familiar with these entities.