Obliteration of processus vaginalis and inguinal hernial sacs in children.

The configuration of the sac in 100 children presenting consecutively with inguinal hernia was studied in an attempt to understand the mechanism of obliteration of the processus vaginalis. Seven clinicoanatomic varieties were found. From a review of these, three possible mechanisms of obliteration of the processus are postulated: (a) progressive fibrous obliteration of the funicular portion of the process in a cephalad direction beginning above the epididymis, (b) initial compression of the funicular portion of the process into a narrow tubular structure by surrounding tissue pressure followed by fibrous pressure followed by fibrous obliteration and (c) initial segmentation of the funicular portion followed by variable fibrous obliteration. The testicular portion of the process, in any of the above mechanisms, shrinks to form two membranes with potential space between them as the contained fluid is absorbed. The types of potential hernial sacs resulting from arrest of any of these forms of obliteration are also described.