The scrotum and its contents are commonly injured during motor vehicle accidents and athletic injuries. Direct blow or straddle injuries result in contusion, hematoma, fracture, or rupture. More than 50% of testicular ruptures occur from a direct blow to the groin during sporting activity. Testicular injuries are surgical emergencies with good prognosis if treated within 72 hours. Ultrasound shows heterogeneous echogenicity within the testis due to areas of hemorrhage or infarction. Other findings include irregular, poorly defined borders, scrotal wall thickening, and hematocele (Figure 11). The tunica is disrupted with testicular rupture, and there may be diminished blood flow in the disrupted capsule. A large hematocele may displace and obscure the underlying testis, leading to a false-positive diagnosis of testicular rupture. In testicular fracture without rupture, the capsule is intact but a discrete fracture plane is visible in only 17% of cases[7,10] (Figure 12). It is important to remember that 10% to 15% of tumors first manifest after trauma and can mimic an injury; therefore, sonographic abnormalities should be followed to resolution if surgery is not performed.
In a patient with polyarteritis nodosa, this testicular sonogram shows a hypoechoic area (arrowheads) caused by vasculitisinduced ischemia.
This sonogram of a different patient following trauma reveals inhomogeneous testicular echotexture and a fracture line (arrow).
Appl Radiol. 2006;35(3):8-17. © 2006 Anderson Publishing, Ltd.