Imaging of thoracic hernias: types and complications

Thoracic hernias are characterised by either protrusion of the thoracic contents outside their normal anatomical confines or extension of the abdominal contents within the thorax. Thoracic hernias can be either congenital or acquired in aetiology. They can occur at the level of the thoracic inlet, chest wall or diaphragm. Thoracic hernias can be symptomatic or fortuitously discovered on imaging obtained for other indications. Complications of thoracic hernias include incarceration, trauma and strangulation with necrosis. Multiple imaging modalities are available to evaluate thoracic hernias. Radiographs usually offer the first clue to the diagnosis. Upper gastrointestinal radiography can identify bowel herniation and associated complications. CT and occasionally MR can be useful for further evaluation of these abnormalities, accurately identifying the type of hernia, its contents, associated complications, and provide a roadmap for surgical planning. In this article, we review the different types of thoracic hernias and the role of imaging in the evaluation of these hernias. TEACHING POINTS: • Protrusion of lung contents beyond the anatomic confines of the thorax constitutes a hernia. • Complications of thoracic hernias include incarceration, trauma and strangulation with necrosis. • Multiple imaging modalities are available to evaluate thoracic hernias. • CT is the imaging modality of choice for identifying thoracic hernias and their complications. • Imaging can provide a roadmap for surgical planning.