Hydrocele Testis

A hydrocele testis is an accumulation of clear fluid in the tunica vaginalis, the most internal of membranes containing a testicle. A primary hydrocele causes a painless enlargement in the scrotum on the affected side and is thought to be due to the defective absorption of fluid secreted between the two layers of the tunica vaginalis (investing membrane). A secondary hydrocele is secondary to either inflammation or a neoplasm in the testis.

A hydrocele usually occurs on one side, but can also affect both sides. The accumulation can be a marker of physical trauma, infection or tumor, but the cause is generally unknown.