A hydrocele is a collection of fluid inside the area of the scrotum, surrounding the testicle. Hydroceles are common in newborn infants and normally resolve after a few months after birth. The main symptom is a painless, swollen testicle, on one or both sides, which feels like a water-filled balloon. 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 blood supply of the testicle.
Update Date 10/2/2013
Updated by: Scott Miller, MD, Urologist in private practice in Atlanta, Georgia. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.