But occasionally, the sac remains open (communicating hydrocele). The sac can change size or if the scrotal sac is compressed, fluid can flow back into the abdomen. Communicating hydroceles are often associated with inguinal hernia.
Older males. A hydrocele can develop as a result of injury or inflammation within the scrotum. Inflammation might be caused by an infection in the testicle or in the small, coiled tube at the back of each testicle (epididymitis).