The etiology of the adult indirect inguinal hernia: revisited.

It has generally been historically stated that indirect inguinal hernias develop only in patients who have a patient processus vaginalis that enlarges to become a hernia sac. Occasionally, this theory has been challenged but without any objective evidence. Herniography was performed by placing 50 mL of nonionic contrast material into the peritoneal cavity. The patient was then placed in a prone position with the head of the table elevated. Films of the inguinal fossae were obtained with the patient straining. The herniogram revealed a right indirect inguinal hernia. There was no left inguinal hernia, nor was there a patent processus vaginalis on the left side. Two years later, the patient developed left inguinal discomfort and swelling and was found to have a moderate-sized left inguinal hernia. At the time of operation, an indirect sac of moderate size was present. A mesh plug repair was performed. This case report is the first published objective evidence that, contrary to common thought, a patent processus vaginalis is not a necessary prerequisite to the development of an indirect inguinal hernia.