A hydrocele is a fluid-filled sac around the testicle that can cause swelling in the scrotum. They are usually not painful but can become quite large and as they get larger, it may cause discomfort in the scrotum when walking or sitting. Hydroceles can be drained by placing a needle into the fluid sac but this treatment leads to a recurrence. For definitive treatment, a hydrocelectomy should be performed. This is a small, usually outpatient procedure, where an incision is made in the scrotum to expose the hydrocele which is then opened, the sac is resected, and the edges oversewn so it does not recur.