Patterns of Pneumatization of Parts of Temporal Bone in High-Resolution Computed Tomography and Its Implications.

Abstract

Objective: Investigate the pneumatization pattern of parts of the temporal bone in high-resolution computed tomography (HRCT) and their associations with age, gender, and squamous chronic otitis media (COM) in the contralateral ear. To investigate the symmetry of pneumatization and correlations between pneumatization patterns of parts of the temporal bone.

Study design: Prospective study.

Setting: Tertiary care center.

Patients: Two hundred sixty patients who underwent HRCT temporal bone.

Interventions and main outcome measures: Evaluation of pneumatization of mastoid and petrous apex as per Han et al. and infralabyrinthine as per Marchioni et al. classification.

Results: The commonest pneumatization patterns were group 4 (32.8%), group 1 (69.7%), and type C (76%) for mastoid, petrous apex, and infralabyrinthine parts, respectively. Group 4 pneumatization of the petrous apex ( w = 0.487) and type A infralabyrinthine pneumatization ( w = 0.315) were significantly associated with group 4 mastoid pneumatization ( p < 0.001) but not vice versa. Significant association was observed between age and pattern of mastoid pneumatization ( w = 0.25; p = 0.002) but not for other parts. No significant gender difference was observed in the temporal bone's pneumatization pattern. A significant symmetry was seen in the pneumatization of two ears for all parts. COM in the contralateral ear was significantly associated with group 3 mastoid pneumatization ( w = 0.16; p = 0.036).

Conclusion: Mastoid shows hyperpneumatization, and other parts show absent pneumatization as commonest pattern, with only one-way correlation between increased pneumatization of other parts and mastoid. COM in the contralateral ear and age show a significant association with the type of mastoid pneumatization, but not other parts.