Assessment of Feeding and Swallowing by Cone Beam Computed Tomography —Changes in Oropharyngeal Airway Shape with Aging—

With super aged society in Japan, the death rate from choking due to blockage of the oropharynx has increased; it is now greater than that from traffic accidents and it is believed that this rate will continue to increase. The shape and function of the oropharyngeal crossing with the respiratory tract are most influential in ensuring that food is carried from the oral cavity to the pharynx and the esophagus. We sought to clarify the changes in the shape and features of the oropharyngeal airway from teenagers to those in their 70 s. A total of 57 patients were grouped by age (teenagers, 20s, 30s, 40s, 50s, 60s and 70s), and all underwent cone beam computed tomography (CBCT) to measure the oropharynx volume, height, cross-sectional area, and length of the superior and inferior extremities. Kruskal-Wallis analysis indicated that the volume and height of the oropharynx did no significant difference among age groups, but there was a different tendency when cross-sectional areas of the superior and inferior extremities were compared between younger and older patients. Further, the shape of the inferior extremity was also different features between younger and older patients. In humans, the oropharyngeal airway plays an important role in carrying food through the esophagus and facilitating phonation. Ideally, it is important for this airway to maintain a constant volume and height. Recently, there has been an increase in the incidence of oropharyngeal airway blockage accidents among the elderly. Declines in feeding and swallowing functions and changes in the form of the oropharynx are major factors in these accidents.