Imaging of acute head and neck infections.

Tonsillar infection is the most common cause of infections of the neck in children and young adults whereas odontogenic infection is the most common cause in older population groups. Other sources of neck infection include the salivary glands, nasal sinuses, middle ear and mastoids, cervical lymph nodes, and trauma. Computed tomography and magnetic resonance imaging have excellent sensitivity for the recognition of deep infections, particularly for the identification of abscess formation and its precise location and extension of disease. A careful assessment of potential severe complications, such as vascular compromise, osteomyelitis, and airway narrowing, should be performed routinely.