Imaging of the Nasal Cavity and Paranasal Sinuses: Anatomy and Anatomic Variations

Abstract

To correctly interpret imaging studies, it is essential to understand the anatomy of the lateral nasal wall and its relationship to adjacent structures. The lateral nasal wall contains three bulbous projections: the superior, middle and inferior turbinates (conchae). The turbinates divide the nasal cavity into three distinct air passages: the superior, middle and inferior meati. The superior meatus drains the posterior ethmoid air cells and, more posteriorly, the sphenoid sinus (via the sphenoethmoidal recess). The middle meatus receives drainage from the frontal sinus (via the frontal recess), the maxillary sinus (via the maxillary ostium and subsequently the ethmoidal infundibulum) and the anterior ethmoid air cells (via the ethmoid cell ostia). The inferior meatus receives drainage from the nasolacrimal duct [1--15].