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Hydrocele at a glance

  • A hydrocele is a fluid-filled sac surrounding a testicle, and sometimes both testicles can have a hydrocele.
  • Most people do not report pain from the hydrocele, and the most common symptom is a swollen scrotum.
  • Hydroceles are most common in newborns, but can also occur in men as they age or due to trauma or infection.
  • They sometimes go away without treatment, but at times surgery or aspiration (draining) is needed to remove the fluid.


Physicians usually diagnose a hydrocele by an exam of the scrotum. The doctor will check for tenderness of the enlarged scrotum and the abdomen. As a part of the exam, the doctor may also shine a light behind each testicle. Hydroceles are filled with fluid so the light will shine through them. If the problem is being caused by a solid mass, such as cancer of the testicles, the light will not pass through.

The doctor could also order blood or urine tests to help determine if an infection is present. An ultrasound may be used to confirm the diagnosis of hydrocele and rule out other possible causes for the scrotal swelling.


Hydroceles are generally not dangerous and often not treated. Hydroceles are only treated when they cause pain, result in embarrassment due to the swelling, do not go away on their own in a year, or very rarely when the size of the hydrocele could affect the function of other parts of the scrotum.

Hydroceles in men under 65 often go away on their own. In older men, a hydrocele frequently does not go away without treatment.

Surgery – hydrocelectomy

If the hydrocele does need to be removed, the most common surgery option is a hydrocelectomy. A small incision is made in the lower scrotum to remove the hydrocele fluid and lining. This procedure can be performed on an outpatient basis with general or regional anesthesia. The patient will be able to go home a few hours after surgery.

Depending on the size and location of the hydrocele, after surgery a tube to drain fluid may be needed, along with dressing to cover the incision. To ease discomfort, surgeons recommend use of a scrotal support strap and an ice pack to help reduce swelling.

Pain after surgery tends to last about a week. The doctor may prescribe pain medication if deemed necessary. It will take a few weeks for the patient to return to normal activity. Ask your surgeon about any postoperative activity limitations.

As with any surgery, risks include blood clots, blood loss, infection, pain and complications from anesthesia.

Needle aspiration

Fluid can also be removed from a hydrocele with a long needle in a process called aspiration. It is common that a hydrocele will return if treated by aspiration. In some cases, a drug may be injected to prevent the sac from refilling. Aspiration is recommended only for men who are not physically cleared for surgery, do not want surgery or who want immediate decompression.

The side effects that are most commonly associated with aspiration are risk of infection and temporary pain in the scrotum.


For more information about our urology services, please call (925) 937-7740.