[Normal anatomy of aditus of antrum and antrum on high-resolution CT and three-dimensional reconstruction].

OBJECTIVE

To study the normal anatomy of aditus of antrum and antrum on the high-resolution CT (HRCT) and the three-dimensional reconstruction, testing the normal range. And comparison was carried out according to the age, sex and side.

METHOD

Ninety cases were randomly selected without ear lesions. Scanning were taken in sagittal, transverse and coronal planes on HRCT respectively. The structure of aditus and antrum was displayed by three-dimensional reconstruction. The left-right distances and up-down distances, antero-posterior distances were measured and analyzed.

RESULT

The image of antrum varied with age, while aditus remained constant on the HRCT and the three-dimensional reconstruction. The average of left-right distance of aditus was (5.19 +/- 1.39) mm, and the average of up-down distance of aditus was (5.74 +/- 1.16) mm. The average of left-right distance of antrum was (8.27 +/- 1.41) mm (<6 years old) and (5.41 +/- 1.32) mm (> or = 6 years old). The average of up-down distance of antrum was (11.78 +/- 1.65) mm (<6 years old) and (9.91 +/- 2.04) mm (> or = 6 years old). The average of antero-posterior distance of antrum was (12.25 +/- 1.23) mm (<6 years old) and (10.05 +/- 1.69) mm (> or = 6 years old). No statistically significant differences were seen in left-right distance of aditus by age, sex and side (P > 0.05). Significant differences in up-down distance of aditus was found between male and female, and the distance in male was greater than that in female (P < 0.05). Statistically significant differences were seen in left-right distance and up-down distance, antero-posterior distance of antrum by age (P < 0.05), but no statistically significant differences by sex or side (P > 0.05).

CONCLUSION

Imaging of aditus ad antrum is relatively constant in the normal persons, while the aditus is more diverse. Significant gender differences were seen in up-down distance. There were significant differences in left-right distance, up-down distance, and antero-posterior distance of aditus among all age groups.