Patent processus vaginalis

Alternative names

Processus vaginalis; Hydrocele

Definition

A hydrocele is a fluid-filled sack along the spermatic cord within the scrotum.

Causes, incidence, and risk factors

Hydroceles are common in newborn infants. The fluid buildup can be on one or both sides of the scrotum.

During normal development, the testicles descend down a tract (tube) from the abdomen into the scrotum. Hydroceles result when this tube fails to close. Peritoneal fluid drains from the abdomen through the open tube. The fluid accumulates in the scrotum, where it becomes trapped. This causes the scrotum to enlarge.

Hydroceles normally resolve after a few months after birth, but their appearance may worry new parents. Occasionally, a hydrocele may be associated with an inguinal hernia. Hydroceles can be easily demonstrated by shining a flashlight through the enlarged portion of the scrotum. If the scrotum is full of clear fluid, as in a hydrocele, the scrotum will light up (transillumination).

Hydroceles may also be caused by inflammation or trauma of the testicle or epididymis, or by fluid or blood obstruction within the spermatic cord. This type of hydrocele is more common in older men.

Symptoms

The main symptom is a painless, swollen testicle, one or both sides, which feels like a water-filled balloon.

Signs and tests

During a physical exam, the doctor would identify an enlarged scrotum that is usually not tender. Often, the testicle cannot be felt because of the surrounding fluid. The size of the fluid-filled sack can sometimes be increased and decreased by pressure to the abdomen or the scrotum.

If the size of the fluid collection is variable, it is more likely to be associated with an inguinal hernia. The fluid in a hydrocele is usually clear. Therefore, a light can be shined through the scrotum, outlining the testicle and indicating the presence of clear fluid. An ultrasound may be done to confirm the diagnosis.

Treatment

Hydroceles are usually not dangerous, and they are usually only treated when they cause discomfort or embarrassment, or they get so large that they threaten the testicule's blood supply.

One option is to remove the fluid in the scrotum with a needle (a process called aspiration). However, aspiration can cause infection, and it is common for the fluid to re-accumulate. Therefore, aspiration is not routine and surgery is generally preferred. On the other hand, aspiration may be the best alternative for people who have certain surgical risks.