Table 3 Grading for the different dimensions of the posterior ethmoid sinus and its incidence
From: Posterior ethmoid sinus: a computed tomography analysis and classification
Posterior ethmoid sinus | Percent |
|---|---|
AP diameter | |
Grade 1 (< 10 mm) | 1% |
Grade 2 (10–15 mm) | 80.5% |
Grade 3 (> 15 mm) | 18.5% |
Transverse diameter | |
Grade 1 (< 10 mm) | 9% |
Grade 2 (10–15 mm) | 86.5% |
Grade 3 (> 15 mm) | 4.5% |
Height | |
Grade 1 (< 10 mm) | 8% |
Grade 2 (10–15 mm) | 84.5% |
Grade 3 (> 15 mm | 7.5% |