<prompt> NOT a content of superior mediastinumPulmonary trunkThymusLeft superior intercostal aeryArch of aoa  <response>: Mediastinum refers to the space between two lungs in thorax. SUPERIOR MEDIASTINUM Space above 2nd costal cailage CONTENTS: thymus, arch of aoa, superior venacava, pulmonary aeries, esophagus, trachea, T1 - T4 veebra, PICA - 1, 2. INFERIOR MEDIASTINUM Space below superior mediastinum, again divided into anterior, middle and posterior mediastinum. CONTENTS: pulmonary trunk, bronchus, thymus, hea, ascending aoa, PICA 3 - 12 esophagus, descending aoa, T5 - T12 veebra. Angle between manubrium of sternum body of sternum is called angle of louis, which is 1630. 