Ultrasound comparison between the testis.
A 25-year-old male patient presented to the emergency department 24 hours after a motorcycle accident, with persistent pain in the left scrotum.
Grayscale sonography reveals an enlarged left testicle with scrotal wall thickening, a heterogeneous parenchymal echotexture and an inhomogeneous hypoechoic fluid surrounding the testis consistent with haematocele (Figure 1). The echogenic contour of the testis that represents tunica albuginea is interrupted, indicating the presence of testicular rupture (Figure 2). It was also observed many focal hypoechoic areas in the parenchyma suggestive of intratesticular haematomas (Figure 2).
Colour Doppler sonography shows a large central area of the testicular parenchyma without vascularity (Figure 3).
Due to the anatomic location, elasticity and mobility of the scrotum, scrotal trauma is a rare event, accounting for less than 1% of all traumatic injuries. [1,2] Most cases occur in young men.  Blunt trauma is the most common type of trauma associated with scrotal injuries. 
Ultrasonography (US) is the initial imaging modality of choice in the assessment of testicular trauma.  Testicular rupture is defined by rupture of tunica albuginea and extrusion of testicular contents into the scrotal sac.  The main US findings of testicular rupture are contour deformity of the testis and a heterogeneous parenchymal echotexture. 
Tunica albuginea rupture is usually associated with disruption of the tunica vasculosa, resulting in ischaemia of a variable portion of the parenchyma and decreased or absent blood flow on colour or power Doppler sonography.  However, the loss of definition of tunica albuginea is considered the only significative predictor of testicular rupture. 
Testicular rupture is an urological emergency, requiring emergent surgery. Nevertheless, undergoing early surgery within 72 hours allows the salvage of more than 80% of ruptured testicles. 
This patient had a non-viable testicle and was submitted to left orchiectomy.
Written informed patient consent for publication has been obtained.
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