Normal cross-sectional anatomy of the nasopharynx, oropharynx, and oral cavity.

The anatomy of the extracranial head and neck is complex and difficult to understand. In contrast to other regions, the majority of lesions involving the upper aerodigestive tract (pharynx and oral cavity) are either visible on endoscopy or palpable on clinical examination. This article describes the normal cross-sectional computed tomography and magnetic resonance imaging anatomy of the upper aerodigestive tract.