Ultrasonography of scrotal trauma.

Ultrasound has emerged as the diagnostic imaging modality of choice in the evaluation of patients with scrotal trauma. Most studies of testicular rupture show great accuracy with virtually no instances of false-positive or false-negative diagnoses. Ultrasonography is capable of differentiating between scrotal hematoma, extratesticular fluid collections, posttraumatic torsion testis, posttraumatic epididymitis, epididymal hematoma, as well as testicular rupture. The differentiation of hematocele from pyocele or exudative hydrocele is generally not possible. In patients with suspected testicular rupture, an accurate diagnosis followed by prompt surgical repair is the key to preservation of testicular function. Ultrasound is an extremely useful adjunct to the physical examination in cases of blunt scrotal trauma both for the differential diagnosis of the enlarged scrotum and for determining the necessity for emergency surgery.