A hydrocele is a space filled with fluid occurring below or next to a testicle in the male scrotum. It is usually painless, and is not to be confused with a hernia, but may occur along with one.
Hydroceles are very common in infants, affecting 1–2 percent of infant boys. They occur as the testicle descends from inside the abdomen and the opening into the scrotum through which it passes does not seal normally. This opening allows abdominal fluid to leak into and collect in the scrotum.
Hydroceles usually go away without treatment within the first year of life. If the fluid persists or becomes uncomfortable, an outpatient operation can be done. A small incision is made, the fluid is drained and the opening from the scrotum to the abdomen is closed to inhibit further fluid accumulation.
The physician’s challenge is to properly differentiate the mass as fluid instead of a herniated intestine, for example, or as testicular torsion or a testicular tumor. This examination is usually accomplished with ultrasound imaging.