Intrathoracic

Intrathoracic is an anatomical and clinical term describing anything located inside the thoracic cavity—the chest. The thorax is bounded by the sternum and ribs anteriorly and laterally, the thoracic vertebrae posteriorly, the diaphragm inferiorly, and the thoracic inlet superiorly. The term is used to distinguish structures and conditions within the chest from those outside it (extrathoracic).

An intrathoracic space includes the mediastinum, pleural cavities and their contents, the pericardial sac, the lungs and bronchial tree, the heart and major vessels, the trachea and esophagus, and portions of the thoracic aorta and other vessels.

In clinical practice, intrathoracic describes diseases, injuries, or procedures confined to this space. Examples include intrathoracic tumors such as lung cancer or thymic tumors; intrathoracic infections including pneumonia and empyema; vascular conditions such as thoracic aortic aneurysm; and conditions involving the intrathoracic airway or pleural space, such as pneumothorax or pleural effusion. It is also used in descriptions of physiological states, such as changes in intrathoracic pressure during breathing or mechanical ventilation.

Intrathoracic surgery refers to operations performed within the chest, including thoracotomy, congenital heart operations, pericardial procedures, and minimally invasive approaches such as video-assisted thoracoscopic surgery (VATS). Common procedures include lobectomy, pneumonectomy, and repair of cardiac or mediastinal structures.

The term is routinely used across radiology, surgery, pulmonology, and critical care to specify the location and context of disease and treatment within the chest.