(MEE-dee-a-stin-AH-toe-mee): A procedure in which the doctor inserts a tube into the chest to view the organs in the mediastinum. The tube is inserted through an incision next to the breastbone.

An incision into the the mediastinum, usually with a mediastinoscope, to view the mediastinum.

a procedure in which the doctor inserts a tube into the chest to obtain biopsy sample/s of the lymph nodes in the chest