Sonography of the testis and epididymis.

Sonography (ultrasound) is the mainstay for imaging morphologic abnormalities of the scrotum and testis. It is used primarily for determining the location and nature of palpable lesions and to demonstrate clinically occult, non-palpable lesions. This article describes the state of the art of scrotal sonography. After an initial presentation of the normal sonographic appearance of the testis and epididymis, the diagnostic evaluation of the most common scrotal disorders is described. Scrotal sonography is characterized by high sensitivity in the detection of intrascrotal abnormalities and is a very good mode for differentiating testicular from paratesticular lesions. However, scrotal sonography is limited in determining whether a focal testicular lesion is benign or malignant. Unsatisfactory results are obtained by conventional sonography in the evaluation of testicular torsion. This gap in the diagnosis of scrotal pathologies is now being reliably filled by colour-coded duplex sonography.