Mediastinum

Description

The mediastinum is the central compartment of the thoracic cavity, located between the lungs and extending from the sternum to the vertebral column. It's divided into superior and inferior mediastinum at the level of T4-T5 (sternal angle). The inferior mediastinum is further subdivided into anterior (thymus remnants), middle (heart and pericardium), and posterior (esophagus, thoracic aorta, azygos system) compartments. Key structures include the heart, great vessels, trachea, esophagus, thoracic duct, vagus and phrenic nerves, and lymph nodes. The mediastinum is clinically significant for masses, infections, and surgical approaches. It provides a pathway for structures traveling between neck, thorax, and abdomen.