[The wall of primary hydrocele in childhood. Light and electron microscopic findings (author's transl)].

Hydroceles of infants and children are characterized by edematous wall-thickening, caused by lacking lymph vessels and venous congestion. The morphologic and clinical differences between hydroceles of infants and children favor the following hypothesis: Pathologically increased filtration of fluid from the parietal tunica vaginalis can't be drained into the peritoneal cavity because the processus vaginalis closes too early and gives raise to hydrocele.