Frequency and Ct Scan Pattern of Incidental Mastoid Air Cell Opacification

Background: Incidental findings of mastoid opacification are increasing as cross-sectional imaging is used more often. Mastoid opacification observed on imaging for unrelated clinical purposes is known as incidental mastoid opacification (IMO). Consultations with otolaryngologists are frequently the result of these findings. The purpose of this study was to ascertain the radiological patterns and frequency of IMO on CT imaging. Methodology: Patients who had CT imaging for non-otologic indications between August 2021 and August 2022 were reviewed in a retrospective cross-sectional study carried out at TikurAnbessa Specialized Hospital. Findings: 123 (8.4%) of the 1,466 patients experienced incidental mastoid opacification. Of these, 54 (43.9%) had bilateral involvement and 69 (56.1%) had unilateral involvement. Four (3.3%) had a combination of partial and complete opacification, 22 (17.9%) had complete opacification, and 97 (78.9%) had partial opacification. In 48 cases (39%), there was concurrent middle ear opacification. Despite these results, radiology reports only reported mastoid opacification in 31 cases (25%) and described it as either otomastoiditis or simple opacification. Only 7 patients (5.7%) were evaluated by an otolaryngologist, and no active mastoiditis was found. In conclusion, 8.4% of patients having CT scans for non-otologic reasons had incidental mastoid opacification. Complete opacification and concurrent middle ear involvement increased the likelihood of reporting. Few cases were referred for ENT evaluation, though, and most were clinically insignificant. These results emphasize how crucial it is to interpret data carefully in order to prevent needless referrals.