A hydrocele occurs from an accumulation of fluid in the tunica vaginalis (a thin pouch that holds the testes within the scrotum). In the fetus, the tunica vaginalis is formed in the abdomen and then migrates into the scrotum with the testes. After the tunica vaginalis is in the testes, it seals off from the abdomen. Some fluid may remain in the area causing a hydrocele.

There are three types of hydroceles—hydrocele of the cord, communicating or noncommunicating:

  • Communicating hydrocele
    A communicating hydrocele occurs from the incomplete closure of the tunica vaginalis, so that a small amount of abdominal fluid may flow in and out of the thin pouch. It is distinctive because the fluid fluctuates throughout the day and night, altering the size of the mass.
  • Noncommunicating hydrocele
    A noncommunicating hydrocele may be present at birth and usually resolves on its own spontaneously within 18 months. A noncommunicating hydrocele in an older child may indicate other problems, such as infection, torsion (twisting of the testes), or a tumor. Always consult your child’s doctor for a diagnosis.
  • Hydrocele of the cord
    This type of hydrocele takes place when fluid is trapped within the tunica vaginalis of the spermatic cord.

A hydrocele is present in as many as 10 percent of all full-term male live births; however, in most cases, it disappears without treatment within the first 18 months. Treatment after this time is usually done for cosmetic reasons as simple hydroclees do not increase the risk to a testicle’s health. Some hydrocleles may also be accompanied by inguinal hernias.

What are the symptoms of a hydrocele?

Although each child may experience symptoms differently, the most common symptom is a fluid mass that is usually smooth and not tender in the scrotum. In the case of a communicating hydrocele, the mass fluctuates in size, getting smaller at night while lying flat, and enlarging during more active periods. The symptoms of a hydrocele may resemble other conditions or medical problems. The specialists at the CHOC Urology Center carefully assess patients to ensure an accurate diagnosis.

How is a hydrocele diagnosed?

Diagnosis of a hydrocele is usually made by a physical examination and a complete medical history. Our specialists may need to determine if the mass is a hydrocele or an inguinal hernia (a weakened area in the lower abdominal wall or inguinal canal where intestines may protrude).

Transillumination (the passage of a strong light through a body structure to permit inspection on the opposite side) of the scrotum can differentiate a hernia from a hydrocele.

Sometimes a scrotal ultrasound will also be completed to visualize the contents of the scrotum.

What is the treatment for a hydrocele?

Most hydroceles will self-resolve within the first 18 months of life. If a hydrocele persists past this time, a surgery may be recommended in order to improve how the scrotum looks. If the size of the hydrocele is also progressing, or the size varies throughout the day a surgery may also be recommended.

A hydrocele surgery is normally performed by making a small incision in the scrotal or inguinal area and draining the fluid while also closing off the opening to the tunica vaginalis. Learn more about hydrocele postoperative care.