To review the anatomy of deep space of head and neck.

To localize a neck pathology in a specific space.

To address the best differential diagnosis according to its origin space and imaging features.

Nowadays, cross-sectional imaging is considered a powerful tool for evaluating head and neck masses. The identification of the lesion relies on both clinical history and CT or MRI features combined with a good Knowledge of the normal anatomy. 

The neck region is anatomically complex, but can be organized into spaces in order to organize the approach to neck masses. A thorough understanding of fascial planes, the various spaces and their normal contents will help the radiologist generate the best differential diagnosis.

The ability to place pathology within a neck space is the first step to generating a diagnosis. And by applying simple concepts of epicenter, and displacement patterns, it is usually possible to assign a space of origin to the mass. Once assigned, judicious application of the limited differential diagnostic considerations of the space can often lead to a correct diagnosis.

The hyoid bone serves to divide the neck into the suprahyoid and infrahyoid areas. Two layers of fascia, superficial and deep, are used to define the spaces of the neck.

The region between the base of the skull and the hyoid bone, not including the orbits, paranasal sinuses, or oral cavity, makes up the suprahyoid space.it includes the pharyngeal mucosal space, the sublingual space, the submandibular space, the parapharyngeal space, the parotid space, and the masticator space. The entire neck (suprahyoid plus infrahyoid) includes the carotid space, retropharyngeal and danger space, and the perivertebral space. Apart from the whole neck area (above), the infrahyoid neck contains also the visceral space.