Background: The middle ear cavity is ventilated through the aditus ad antrum. Aditus
blockage contributes to the pathology of otitis media.
Objective: To determine the normal values of the aditus ad antrum diameter on computed tomography
and to investigate its relationship with chronic otitis media and related pathologies
(tympanosclerosis and myringosclerosis).
Methods: The temporal CT images of 162 individuals were evaluated retrospectively. In the axial
sections, the inner diameter of the aditus was measured at the narrowest point at the cortex. The
differences in diameter were compared between diseased and healthy ears.
Results: In healthy individuals, the diameter was narrower in women. There was no difference between
the right and left ears in healthy subjects. No correlation was found between age and diameter.
In male patients with myringosclerosis, the diameter was slightly narrower on both sides but
more marked on the left. In female patients with myringosclerosis, the diameter in both ears was
slightly narrower. In cases of otitis media and tympanosclerosis, the diameter was less than that of
healthy individuals, despite the lack of statistically significant result in all cases.
Conclusion: The aditus ad antrum was narrower in diseased ears, indicating that a blocked aditus
may contribute to the development of otitis media, as well as mucosal diseases.