Imaging in infections of the head and neck.

Infections of the head and neck vary in their clinical course and outcome because of the diversity of organs and anatomic compartments involved. Imaging plays a central role in delineating the anatomic extent of the disease process, identifying the infection source, and detecting complications. The utility of imaging to differentiate between a solid phlegmonous mass and an abscess cannot be overemphasized. This review briefly describes and pictorially illustrates the typical imaging findings of some important head and neck infections, such as malignant otitis externa, otomastoiditis bacterial and fungal sinusitis, orbital cellulitis, sialadenitis, cervical lymphadenitis, and deep neck space infections.