Cephalometric evaluation and measurement of the upper airway

Abstract

<h2>Abstract</h2> The growth and function of the nasal cavities, the nasopharynx, and the oropharynx are closely associated with the normal growth of the skull. In this respect, knowledge of normal cranial growth has often been gained by recognition and observation of abnormal development. Mouth breathing, which has been associated with specific facial growth patterns, may result from obstruction or restriction of any part of the upper airway. The use of lateral cephalometric radiographs to evaluate the upper airway is somewhat limited as they provide 2-dimensional images of the nasopharynx, which consists of complex 3-dimensional anatomical structures. Not withstanding this observation, some workers have found that a significant correlation exists between the results of posterior rhinoscopy and radiographic cephalometry in the assessment of adenoid size. This article reviews some of the most important cephalometric measurements that have been used to determine the patency of the upper airway. It is an important aim of this review to ensure that there is agreement between the cephalometric measurements used in studies of the upper airway and similar measurements used in physical anthropology and human craniometry. Additionally, one example is given of volumetric radiographic techniques that promise to further elucidate aspects of the normal, and the abnormal, functions of the upper airway.