A Study on the Position of the Mastoid Antrum of Korean People in the Temporal Bone CT

Shin, Jin Ahn; Cho, Yong Bum; Ahn, Ock Sun

Abstract

BACKGROUND AND OBJECTIVES: Computed tomography of the temporal bone can provide otologists precise informations regarding the middle ear diseases. In this study, we aimed to measure the distance of mastoid antrum using the temporal bone CT for predicting the distance of mastoid depth during the mastoid surgery. MAERIALS AND METHODS: We analyzed normal ears of 88 patients who visited the Department of Otolaryngology, Chonnam University Hospital during the period between Aug. 1996 and Aug. 1997. These patients demonstrated unilateral chronic otitis media, temporal bone fracture, and traumatic facial nerve palsy.
RESULTS
The mean distance of mastoid antrum was 11.45mm. The distance of mastoid antrum according to age distribution showed 7.75 mm in 0-4 year old group, 10.35 mm in 5-9 year old group, 10.71 mm in 10-14 year old group, 11.50 mm in 15-19 year old group, and 11.93 mm in over 20 year old group. The distance also differed between males and females, with 2.84 mm for male and 11.24 mm for female.
CONCLUSION
For the group under 20 years old, the distance of mastoid antrum increased as the patient's age became older. Especially, the group who were between 5 to 9 years old showed marked increase in the distance, and the distance did not differ between male and female. The distance of the mastoid antrum of the Korean adults was 10.1-13.7 mm and it represents some difference when compared with that of Westerners.