Idiopathic Eventration of the Diaphragm

Abstract

TO one who makes an intensive study of any portion of the body will quickly come the realization that physical development is not as constant or as symmetrical as is generally supposed. Usually the departures in development from what is considered to be normal are slight, but at times the embryological mal-development may be so great as to threaten, or even preclude, the existence of the individual. The development of the body is accurate in its gross aspects, but in its minutiae there is constant failure of repetition. One of these abnormalities of development is eventration of the diaphragm, and the condition may be defined as an idiopathic lesion in which one-half of the diaphragm becomes greatly relaxed, so that the abdominal organs encroach upon the thoracic cavity. The diaphragm is thin and fibrotic; there is no degeneration of the corresponding phrenic nerve. The history of this condition dates back to the time of Petit (1790) and Cruveilhier (1829), who applied, the general term “eventration” to all abdominal hernias, and regarded the diaphragm as subject to the same influences, which result in thinning and relaxation of the anterior abdominal wall. As applied to the diaphragm, the condition has been termed “eventration of the diaphragm.” But however incorrect may have been its original interpretation, the term “eventration of the diaphragm” has come to be generally accepted, especially in this country. The clinical recognition of eventration is usually a most difficult task. As a matter of fact, previous to the time when aid could be given by radiographic examination the diagnosis had never been made at all during life. The difficulties of interpretation of the confusing physical signs, combined with the great rarity of the lesion, make the diagnosis almost impossible without the aid of the X-ray. The physical signs depend in a great measure upon the degree of eventration, the state of fullness of the stomach and intestines, and the side on which the lesion occurs. In left-sided eventration the usual physical signs are diminished expansion of the left thorax and absence of Litten's sign. At the left base the respiratory murmur is replaced by splashing and metallic sounds when the stomach and intestines contain food or fluids. When they are empty the left base gives a tympanitic note, absence of voice and breath sounds, and absence of vocal fremitus. The heart is usually displaced toward the side opposite the lesion. In fact, dextro-cardia is one of the most important indications of an abnormality of the diaphragm. In right-sided eventration the physical signs are modified by the presence of the liver, and whether or not stomach and bowel come to lie between the liver and diaphragm. The postmortem examinations which have been made have revealed a fairly uniform picture. The lung is small and hypoplastic, but atelectasis has never been observed.