Male toddler with a left groin mass

US of encysted hydrocele of spermatic cord
Sagittal (above) US of the left groin shows an anechoic fluid collection in the left inguinal canal that does not communicate with the peritoneal cavity above or the scrotum below. Transverse US (below) better shows the septation within the fluid collection.

The diagnosis was an encysted hydrocele of the spermatic cord.