Ultrasound imaging of the scrotum provides pictures of the testicles and the surrounding tissues of a man or a boy. Ultrasound imaging of the scrotum is the primary imaging method used to evaluate disorders of the testicles, epididymis (a tube immediately next to a testis that collects sperm made by the testicle) and scrotum.

This study is typically used to:

  • determine whether a mass in the scrotum felt by the patient or doctor is cystic or solid and its location
  • diagnose results of trauma to the scrotal area
  • diagnose causes of testicular pain or swelling such as inflammation or torsion
  • evaluate the cause of infertility such as varicocele
  • look for the location of undescended testis

Ultrasound can often detect an absent or undescended testicle as well. The testicle normally migrates from the abdomen, down the inguinal canal and then into the usual position in the scrotal sac. If it is not present in the scrotal sac, it may have stopped on its way and lie in the inguinal region, in which case the ultrasound examination will often see it. If it has not left the abdominal cavity, it may not be seen by sonography. If a testicle is not detected, a urologist may be consulted in order to decide whether additional imaging such as an MRI is needed to determine its location. If the testicle is found to be in the inguinal region, it can be moved into the scrotum. If left in the abdomen too long, it may become cancerous and may need to be removed.

Ultrasound can identify testicular torsion, the twisting of the spermatic cord that contains the vessels that supply blood to the scrotum. Caused by abnormally loose attachments of tissues that are formed during the fetal development, torsion commonly appears during adolescence, and less often in the neonatal period, and is very painful. Torsion requires immediate surgery to avoid permanent damage to the testes.

Ultrasound also can be used to locate and evaluate masses (lumps or tumors) in the testicle or scrotum. Collections of fluid and abnormalities of the blood vessels may appear as masses and can be assessed by ultrasound. Masses, both outside and within the testicles may be benign or malignant and should be evaluated as soon as they are detected.