Classification of temporal bone pneumatization based on sigmoid sinus using computed tomography.
OBJECTIVE
To analyse several reference structures using axial computed tomography (CT) imaging of the temporal bone, which may reflect pneumatization of the entire temporal bone by statistical correlation to the actual volume of the temporal bone measured using three-dimensional reconstruction.


METHODS
One hundred and sixteen temporal bones were studied, comprising 48 with normal findings and 68 sides showing chronic otitis media or temporal bone fracture. After measuring the volume of temporal bone air cells by the volume rendering technique using three-dimensional reconstruction images, classification of temporal bone pneumatization was performed using various reference structures on axial images to determine whether significant differences in the volume of temporal bone air cells could be found between the groups.


RESULTS
When the sigmoid sinus at the level of the malleoincudal complex was used in the classification, there were statistically significant differences between the groups that correlated with the entire volume of the temporal bone. Grouping based on the labyrinth and the ascending carotid artery showed insignificant differences in volume. Furthermore, there was no significant correlation between the cross-sectional area of the antrum and the entire volume of the temporal bone.


CONCLUSIONS
The degree of pneumatization of temporal bone can be estimated easily by the evaluation of the air cells around the sigmoid sinus on axial CT images.
Han
S-J
SJ
Department of Otorhinolaryngology, National Health Insurance Corporation Ilsan Hospital, and Yonsei University College of Medicine, Seoul, Republic of Korea.
Song
M H
MH
Kim
J
J
Lee
W-S
WS
Lee
H-K
HK
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D010033:Otitis Media / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted; D012887:Skull Fractures / Q000000981:diagnostic imaging*; D013701:Temporal Bone / Q000000981:diagnostic imaging* / Q000293:injuries; D014057:Tomography, X-Ray Computed / Q000379:methods