Skeletal Age and Growth of the Nasopharynx in the Sagittal Plane: A Cephalometric Study

Abstract The nasopharynx consists of a group of muscular organs, and its size and shape depend largely on the surrounding bony structures that are, for the most part, the bones of the base of the cranium. With lateral cephalometric x-ray techniques it is possible to study the anatomy of the nasal airway and throat in the sagittal plane. Such studies show that the amount of adenoid tissue present must be assessed relative to the dimensions of the nasopharynx. The size and shape of the nasopharynx may be described in terms of its height, width, and depth. Previous studies agree that in growing children both the height and the width of the nasopharynx are closely dependent on age. There is, however, some difference of opinion as to the relationship between age and the sagittal depth of the nasal part of the pharynx. This cross-sectional study uses a sample of African children between the ages of 8 and 16 years to quantify growth of the nasopharynx and its contained adenoidal tissue. The data are ranked according to chronologic as well as skeletal age. Although the mean size of the adenoids tended to decrease with age, this trend was reversed at the onset of puberty. After puberty the mean size of the adenoids once more decreased. From this study it appears that the data for growth studies of the nasopharynx should be arranged according to skeletal, rather than chronologic, age. The graphs that result from the former method differ greatly from those that result from data arranged by chronologic age. Pubertal growth spurts, as well as sexual dimorphism in the growth patterns, are clearer when the data are ranked according to skeletal age. The present study is the first of its kind to use skeletal age to study growth of the adenoids. It is hoped that others will follow this lead so that comparative data for white children may become available.