It is located in the anterior right superior mediastinum.

Superior to the thoracic inlet is the root of the neck, and the superior mediastinum is related inferiorly.

A further Level VII to denote lymph node groups in the superior mediastinum is no longer used.

The superior mediastinum extends superiorly above the plane, while the inferior mediastinum extends inferiorly.

The superior mediastinum is that portion of the interpleural space which lies between the manubrium sterni in front, and the upper thoracic vertebrae behind.

The thoracic cavity is further separated into the pleural cavity which contains the lungs and the superior mediastinum which includes the pericardial (heart) cavity.

The thymus is composed of two identical lobes and is located anatomically in the anterior superior mediastinum, in front of the heart and behind the sternum.

It originates along the aortic arch, and travels upward through the superior mediastinum to the level of the left sternoclavicular joint, where it is continuous with the cervical portion.

There are several other minor but important vessels and nerves passing through, and an abnormally large thyroid gland may extend inferiorly through the thoracic inlet into the superior mediastinum.

In general, EUS is most appropriate for evaluation of the posterior inferior mediastinum while mediastinoscopy or EBUS are best for the anterior superior mediastinum.

The (transverse) thoracic plane or transthoracic plane is a geometric plane used to divide the mediastinum (the middle section of the chest cavity) into the superior mediastinum and the inferior mediastinum.

In the superior mediastinum the trachea is somewhat to the right of the esophagus which makes it often possible to reach left-sided area 2 and 4 lymph nodes and, less often, right sided paratracheal lymph nodes.