Herniation of the liver although rare should be included in the differential diagnosis of an intrathoracic mass.
A 35-year-old hypertensive male presented to the emergency room with shortness of breath on exertion following an episode of chest tightness three days ago. Also complained of a gradually worsening headache with mild neck stiffness and fever. He was a chronic cocaine abuser and admitted to using cocaine over the last few days. Denied any constitutional symptoms, or weight loss. Examination revealed a blood pressure of 160/93, mild neck stiffness and decreased breath sounds on the over the left side of the chest. Routine laboratory investigation including cardiac enzymes and electrocardiogram was unremarkable. Lumbar puncture was negative. Chest x-ray revealed a retro cardiac mass. Chest CT showed a 9.1 X 5.1 cm well circumscribed soft tissue mass with central fat attenuation abutting the left side of the heart at the level of diaphragm. The soft tissue component of this mass had similar hounsfield units as the liver (Fig-1). On further questioning, it was found that fifteen years earlier, he was involved in an automobile accident and had sustained traumatic contusions to the chest. Liver colloids scan showed an area of localization involving the superior medial aspect of the left hemi-diaphragm (Fig-2). Subsequent selective hepatic angiography revealed that the intra thoracic mass had arterial supply from the left hepatic artery. The headache was due to an ruptured aneurysm which was later embolised. The patient refused any kind of surgical intervention.
Diaphragmatic ruptures usually result from accidental and violent trauma, occurring in approximately 5 % of patients who have suffered major blunt trauma and is recognized at the time of injury in less than 50 per cent. 95 % of the time it occurs on the left side and seldom includes the liver. This is the most common side and is attributed to the diminished buffering force under the left dome of the diaphragm. Visceral herniation and diaphragmatic rupture in many cases may remain occult or asymptomatic for months or years and may not be diagnosed as seen in our case, which was discovered incidentally fifteen years later after a remote motor vehicle accident. Differential diagnosis of liver hernia includes lung, pleural, and diaphragmatic neoplasms. The liver can also protrude into the thorax via diaphragmatic hernias such as through the foramen of Bochdalek and Morgagni. Congenital diaphragmatic eventration should be excluded. Radionuclide scanning and magnetic resonance imaging have been demonstrated to be relatively accurate in defining the location of the herniated liver in blunt diaphragmatic trauma. An invasive procedure like angiography confirms the diagnosis but is not essential.
This case illustrates the importance of a detailed history from the patient and the need to include herniation of the liver in the differential diagnosis of thoracic masses. A varying period of time ranging from months to years can elapse before discovery, either because of the onset of symptoms or as an incidental finding. When delayed herniation occurs the initial trauma may be long forgotten and the significance of it is not appreciated.
M. Nashat, None.