The anterior mediastinum is posterior to the body of the sternum and anterior to the pericardial sac (see Fig. 3.57).
Its superior boundary is a transverse plane passing from the sternal angle to the intervertebral disc between vertebra TIV and TV, separating it from the superior mediastinum.
Its inferior boundary is the diaphragm.
Laterally, it is bordered by the mediastinal part of parietal pleura on either side.