Computed Tomographic Comparison of Length, Width and Angulation of Ethmoidal Infundibulum in Patients With and Without Maxillary Sinusitis.

Ethmoidal infundibulum (EI) is an important part of the osteomeatal complex, which provides the main pathway for the maxillary sinus drainage. This study aimed to compare the length, width, and angulation of EI in patients with/without maxillary sinusitis using computed tomography (CT). This cross-sectional study evaluated 818 spiral CT scans of patients with/without maxillary sinusitis (n = 409 maxillary sinuses in each group) classified according to the clinical symptoms and the Lund-Mackay score for mucosal thickening. The degree of mucosal thickening (on axial and coronal sections), anatomical variations namely concha bullosa (CB), ethmoidal bulla (EB), and Haller cells (HCs), the form of EI (on coronal sections), the length, width and angulation of EI, and degree of nasal septal deviation (on coronal sections) were all evaluated. Data were analyzed by parametric and non-parametric tests (alpha = 0.05). The frequency of EB (P < 0.001), EI form (P < 0.001) and HC (P = 0.011), and the length and width of EI (P < 0.001) were significantly different in patients with and without maxillary sinusitis. The length and width of EI were significantly correlated with the degree of mucosal thickening (P < 0.01). The frequency of CB (P = 0.002), EB (P < 0.001), and HC (P = 0.002), and the EI form (P < 0.001) were significantly different in groups with different degrees of mucosal thickening. EI was wider and shorter in patients with maxillary sinusitis. By an increase in mucosal thickness, the length of EI decreased while its width increased. Also, the frequency of EB and HC, and the EI form were significantly different in the two groups.