Mediastinal mass
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Mediastinal mass Microchapters |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Trusha Tank, M.D.[2]
Synonyms and keywords: Mediastinal enlargement; mass in the mediastinum
Overview
The mediastinum is a non-delineated group of structures in the thorax (chest), surrounded by loose connective tissue. It is the central compartment of the thoracic cavity. It contains the heart, the great vessels of the heart, esophagus, trachea, thymus, and lymph nodes of the central chest. A wide variety of diseases involving these organs can present as a mediastinal mass or widening of the mediastinum on imaging studies. Mediastinal widening is diagnosed by the mediastinum measuring greater than 8 cm in width on PA chest x-ray. On the basis of cross-sectional imaging, mediastinum can be divided into 3 groups: 1) Prevascular, which contains thymus, fat, lymph nodes and left brachiocephalic vein. 2) Visceral compartment, which contains trachea, carina, esophagus, lymph nodes, heart, ascending thoracic aorta, aortic arch, descending thoracic aorta, superior vena cava, intrapericardial pulmonary arteries, and thoracic duct. and 3) Paravertebral compartment, which contains the thoracic spine and paravertebral tissue. The mediastinal mass may present with symptoms or even without any symptoms. A mediastinal mass may cause a variety of symptoms by the mass pressing against other mediastinal structures, collectively known as mediastinal syndrome. Mediastinal mass can be differentiated according to the content of the mass such as cystic mass, fatty mass or solid (tumor).