A hydrocele occurs from a build up of fluid in the thin pouch that holds the testes within the scrotum called the tunica vaginalis.
In the fetus, the tunica vaginalis is formed in the abdomen and then moves into the scrotum with the testes. After the pouch is in the testes, it seals off from the abdomen. Hydroceles can be 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 one year. A noncommunicating hydrocele in an older child may indicate other problems, such as infection, torsion (twisting of the testes), or a tumor.
A hydrocele is present in as many as 10% of all full-term male live births; however, in most cases, it disappears without treatment within the first year.
The following are the most common symptoms of hydrocele:
A mass or swelling that is usually smooth and not tender. The swelling is generally painless and pain is a reason to contact your medical provider immediately.
A communicating hydrocele will fluctuate in size, getting smaller at night while lying flat, and increasing in size during more active periods.
If the hydrocele is large and tense, it may require more immediate attention.
The symptoms of hydrocele sometimes look like other conditions or medical problems. Always see your child’s health care provider for a diagnosis.
Diagnosis of a hydrocele is usually made by a physical exam and a complete medical history. Your child's health care provider 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 so that the health care provider can inspect it from the opposite side) of the scrotum can tell the difference between a hernia from a hydrocele.
A noncommunicating hydrocele usually resolves on its own by the time the child reaches his first birthday. Resolution occurs as the fluid is reabsorbed from the pouch.
A hydrocele that persists longer than 12 to 18 months is usually a communicating hydrocele. A communicating hydrocele usually requires surgical repair to prevent an inguinal hernia from occurring. The surgery involves making a small incision in the groin or inguinal area and then draining the fluid and closing off the opening to the tunica vaginalis.