Testicular hydrocele is a condition in which fluid builds up inside the scrotal pouch. It occurs most often in newborn babies, which we call congenital hydrocele.
Transillumination of the scrotum is a very simple diagnostic test to check for hydrocele. It consists of applying a light source to the largest part of the scrotum. If hydrocele is present, the testicle is illuminated as a result of the clear fluid inside.