Diaphragmatic herniation through the space of Morgagni.

In most cases diaphragmatic herniation through the space of Morgagni is asymptomatic and is first noted in routine roentgenograms of the chest. The diagnosis must be considered when shadows are seen in the anterior cardiodiaphragmatic angle. Lateral views are valuable in localizing the lesion. Simple procedures such as pneumoperitoneum should be used in differential diagnosis but when the diagnosis cannot be established by these simpler means exploratory thoracotomy is indicated, because of the possibility of carcinoma of the middle lobe of the lung. If diagnosis is established, thoracotomy is indicated as an elective procedure for repair of the defect, which may have serious consequences. Nine cases of diaphragmatic herniation through the space of Morgagni are summarized and a case report is included which illustrates the potential danger of this condition.