extrathoracic

Extrathoracic refers to something situated outside the thoracic cavity, which contains the heart and lungs. In medical usage, the term is often contrasted with intrathoracic, meaning within the thorax. It is a descriptive location term used in anatomy, pathology, radiology, and clinical practice.

Common contexts include extrathoracic airways and extrathoracic structures. The extrathoracic airways comprise parts of the upper airway outside the thoracic inlet, such as the nasal passages, nasopharynx, oropharynx, and larynx; by contrast, the intrathoracic airways lie within the chest, including the trachea and main bronchi. Extrathoracic masses or lymphadenopathy describe abnormalities located in regions such as the neck or upper regions of the chest above the thoracic inlet. Extrathoracic tumors may, for example, metastasize to cervical nodes, whereas intrathoracic tumors lie within the chest cavity.

In imaging and clinical practice, the term helps specify the location of disease or procedures. For instance, extrathoracic airway obstruction involves structures above the thoracic inlet, while intrathoracic obstruction affects the trachea or bronchi inside the chest. The concept extends to other organs that span the neck or cervical region, such as portions of the esophagus or vessels that lie outside the thorax.

Etymology and usage notes: extrathoracic is an anatomical adjective formed from extra- (outside) and thoracic (relating to the thorax). It is primarily used in clinical and radiologic contexts to localize pathology relative to the chest.