The dimensions of the nasopharynx, the adenoids and the nasopharyngeal airway were analyzed in twelve subjects selected from the longitudinal growth study of the Child Research Council of Denver. 2. The nasopharyngeal area was defined by four skeletally defined lines which formed a trapezoid. The nasopharyngeal area was divided into an adenoid-pharyngeal wall and airway areas which were measured using a polar planimeter. The trapezoid analysis proved to be a useful technique for quantification of nasopharyngeal dimensions. 3. The growth of the nasopharynx from nine months to 18 years was established and reflected the different growth patterns of males and females. 4. The sphenoid line/palatal line angle (theta) and nasopharyngeal depth were established early in life and contributed little to the increase of nasopharyngeal area. The increase in nasopharyngeal area corresponded to the descent of the palate from the sphenoid bone which increased nasopharyngeal height. 5. Restriction of the nasopharyngeal airway frequently occurred during the pre- and early school years due to adenoid hypertrophy which exceeded the usual increase in nasopharyngeal capacity. 6. The nasopharyngeal airway increased during pre- and early adolescence due to the concurrent increase in nasopharyngeal area and adenoid involution. 7. Ten subjects had a history of tonsil and adenoid surgery, but of these only five demonstrated what appeared to be complete removal of nasopharyngeal and adenoid tissue as seen on postsurgical radiographs. The possibility that surgical technique may be the critical factor in the completeness of adenoid removal is presented. 8. The mandibular angle did not apear to be affected by periods of nasopharnygeal airway obstruction is any of the subjects in this study. However, an expanded longitudinal study would be required to determine if restriction of the nasopharyngeal airway influences facial form and occlusion.
