Background/Objectives: The anatomical relationship between the oval window (OW) and the facial nerve (FN) is of significant importance in the context of stapes and middle ear surgery. However, the influence of mastoid pneumatization on OW morphology and FN proximity remains to be elucidated. Methods: This retrospective study included 220 radiologically normal temporal bones from 110 adults. OW width, OW height, OW niche width, FNt–OW distance, FNm–OW distance, OW–mastoid cell distance, and OW–FNm–FNt corridor area were measured on HRCT images. Mastoid pneumatization was classified using a sigmoid sinus-based grading system. RASCI was developed by integrating OW morphology, OW niche width, and mastoid pneumatization. Results: The mean width of the OW, the height of the OW, and the width of the OW niche were 2.41 ± 0.92 mm, 1.38 ± 0.36 mm, and 1.03 ± 0.38 mm, respectively. The mean FNt–OW and FNm–OW distances were recorded as 0.93 ± 0.33 mm and 2.78 ± 0.94 mm, respectively. It was established that larger OW dimensions and FN-OW distances were associated with higher levels of mastoid pneumatization. The radiological–anatomical constraint was categorised as low in 21.4% of cases, moderate in 69.5%, and high in 9.1% of the temporal bones (RASCI). Conclusions: Mastoid pneumatization appears to be associated with OW morphology and FN–OW spatial relationships. The RASCI could provide an initial HRCT-based framework for grading the constraints of the OW-FN corridor; however, prospective surgical validation is required.

Background/Objectives: Allergic rhinitis (AR) is characterized by dynamic mucosal congestion, yet the nasal septal body (NSB), inferior turbinate (IT), and adjacent airway passages have rarely been assessed together. We evaluated whether AR is associated with a multilevel structural–airway pattern while limiting confounding by marked septal deviation. Methods: This retrospective cross-sectional study included 301 adults with septal deviation < 8° (163 patients with clinically diagnosed AR and 138 participants in a clinically defined non-AR comparison group). Coronal computed tomography measurements included total transverse NSB width, dominant IT width, and adjacent airway widths. Between-group differences were evaluated using effect sizes and multivariable regression adjusted for age, sex, and septal deviation angle. Correlation, interaction, and sensitivity analyses assessed structure–airway relationships. Results: Patients with AR had greater NSB width (11.92 ± 1.81 vs. 10.80 ± 1.89 mm; Hedges’ g = 0.605) and dominant IT width (12.78 ± 1.69 vs. 10.41 ± 1.83 mm; g = 1.350), together with smaller adjacent airway widths. All four primary comparisons remained significant after Holm correction and adjustment (all p < 0.001). The NSB–IT correlation (rho = 0.257) was attenuated after adjustment for AR (partial rho = 0.089; q = 0.124), whereas inverse structure–airway associations persisted. A significant AR-status × IT-width interaction was observed for medial airway width (interaction q = 0.030). Conclusions: At the time of CT, patients with AR had greater NSB and IT widths and smaller corresponding regional airway dimensions, with a larger between-group morphometric difference at the IT level. These findings support a multilevel anatomical view of the nasal airway in AR, in which the NSB and IT are best interpreted together with their adjacent airway spaces rather than as isolated structures. Their clinical relevance, however, requires validation against symptoms and objective airflow measures.

Zygomatic sutures are key landmarks in midfacial trauma, yet comparative data on their projected geometry and individual-level bilateral correspondence wit