RESUMEN
BACKGROUND AND OBJECTIVES: Computed tomography of the temporal bone (TBCT) provides us many information about the status of temporal bone and middle ear, and is very important for surgical planning. We studied the relations of facial nerve and other structures in temporal bone and factors influencing access to facial recess according to the pneumatizaton of temporal bone. MATERIALS AND METHOD: A total 177 ears were analyzed. With the coronal section on the level just below the second genu of facial nerve, we measured the distances and angle between important surgical landmarks, and compared the data according to the mastoid pneumatization. RESULTS: The distance from sigmoid sinus to posterior wall of external auditory canal, and the distance from sigmoid sinus to line which was drawn at facial nerve parallel to posterior wall of external auditory canal were significantly influenced by temporal bone pneumatization (p<0.05). Temporal bone pnuematization gave no influence on the position of facial nerve, size of facial recess, and posterior fossa. CONCLUSION: Anterior projection of sigmoid sinus into mastoid antrum, which was influenced by pneumatization of mastoid antrum, was the most important factor influencing access to facial recess area.