A hydrocele is an accumulation of fluid within the tunica vaginalis, which is the inner most membrane surrounding the testicle.
The accumulation of fluid results in painless enlargement of the scrotum on the affected side. In adults, hydroceles are usually due to defective absorption of fluid from the tunica vaginalis, but in children, a hydrocele is often the result of persistent communication between the peritoneal cavity of the abdomen and the tunica vaginalis, known as a patent processes vaginalis. In young children less than 18 months of age, hydroceles can often resolve spontaneously as the processes vaginalis seals. If a child has a persistent hydrocele beyond this age, surgical intervention is usually recommended. The procedure is performed through a small groin incision. It is an outpatient procedure that is well tolerated in children and associated with a low complication rate and a low recurrence rate.