Influence of mastoid pneumatization degree on the facial canal position within the skull base in pediatric population: a computed tomography study

Purpose: This study aimed to evaluate the developmental pattern of mastoid pneumatization in the pediatric population and to investigate its relationship with the anatomical positioning of the mastoid segment of the facial canal.Materials and Methods: Computed tomography images of patients were retrospectively analyzed. Pneumatization degree was classified into four categories: The hypopneumatization, moderate, good, and hyperpneumatization. Measurements of the facial canal, including its distance to the external acoustic meatus, sigmoid sinus, posterior cranial fossa and mastoid surface, were obtained by two independent observers. Results: A total of 197 children (91 males,106 females; mean age 6.31±5.36 years) were included. Pneumatization degree differed significantly across age groups, with hypopneumatization most commonly observed in the infancy period and increasing progressively until the post-pubescent stage. Measurements of the facial canal varied significantly across pneumatization categories: The distance between the canal and the mastoid surface was greatest in the hyperpneumatized group (14.34±2.91 mm), whereas the canal sigmoid sinus distance was significantly larger (10.77±2.66 mm) in moderately pneumatized bones. Conclusion: Mastoid pneumatization demonstrates a clear age-dependent progression throughout childhood and adolescence, and the degree of pneumatization significantly influences the spatial relationships of the mastoid segment of the facial canal.