Morphometric Study of Pharyngeal Orifice of Auditory Tube in South Indian Population

Abstract

Auditory tube extends from the anterior wall of middle ear to the lateral wall of the nasopharynx at the level of inferior turbinate. It plays an important role in maintaining the equilibrium of air. In the patients suffering from chronic otitis media, the auditory tube plays an very important landmark for the endoscopic evaluation and for transnasal approach to the infratemporal fossa. The present study was aimed to locate the pharyngeal orifice of the auditory tube in relation to the important anatomical landmarks. The study was carried out on 50 sagittal head and neck sections of formalin fixed cadavers. The pharyngeal opening of auditory tube was looked for its shape, size and position. The anatomical landmarks with reference to the pharyngeal opening of auditory tube taken were posterior end of inferior turbinate, perpendicular distance from the clivus, from the roof of nasopharynx, from the posterior end of hard palate and from the anterior arch of atlas. The distance from these anatomical landmarks to the pharyngeal orifice of auditory tube were measured using digital vernier calipers. The mean and standard deviations of the distances were calculated and tabulated. The measured distances were slightly higher on the right than the left side. These differences were not statistically significant. The present study is useful for otorhinolaryngologists to locate the position of pharyngeal opening of auditory tube endoscopically and evaluate patients with diseases of middle ear.