Impact of nasal septal deviation, age, and sex on anterior, middle, and posterior clinoid process pneumatization: a morphological computed tomography study.

Abstract

Background: Clinoid process pneumatization is a critical anatomical variation that influences surgical exposure and complication risks in skull base approaches. This study aimed to comprehensively evaluate the pneumatization patterns of the anterior (ACP), middle (MCP), and posterior clinoid processes (PCP) and to determine the effects of age, sex, and nasal septal deviation (NSD) parameters, specifically angle severity and laterality, on these aeration patterns.

Methods: Computed tomography images of 250 adults (125 females, 125 males; aged 18-70 years) were retrospectively evaluated. Pneumatization patterns of the ACP and PCP were classified using a four-type grading system (Type 0-III). In addition, the presence of the MCP and its pneumatization status were evaluated. NSD was evaluated for laterality and angle severity (mild:<9°, moderate:9°-15°, severe:>15°). Statistical associations were assessed using chi-square tests and multivariate regression models.

Results: Type 0 (no pneumatization) predominated across all processes (ACP:81.8%, MCP:82.4%, PCP:82.6%), while Type III (total pneumatization) was rare (ACP:2.0%, PCP:2.2%). While univariate analysis showed age-related associations across all regions, multivariate logistic regression identified an independent association between age and ACP pneumatization, with younger individuals (18-34 years) exhibiting lower degrees of aeration (p < 0.01). Male sex was independently associated with bilateral MCP pneumatization (OR:3.016, p < 0.001) and right PCP pneumatization (OR:2.234, p = 0.032). Severe NSD angle (> 15°) was strongly associated with bilateral PCP pneumatization (p < 0.001) and higher-grade ACP aeration (p < 0.01). Furthermore, MCP presence showed strong ipsilateral clustering with ACP and PCP pneumatization patterns (p < 0.001).

Conclusion: Clinoid process pneumatization demonstrates distinct anatomical associations with NSD angle severity, age, and sex. A severe NSD angle (> 15°) showed the strongest independent association with higher-grade pneumatization, particularly in the ACP and PCP, whereas NSD laterality was not independently associated with pneumatization. These findings support the inclusion of NSD angle severity in the radiological assessment of patients undergoing preoperative skull base CT, especially when extensive clinoid pneumatization may influence surgical planning.