LAUSR

Background The nasal septum is composed of cartilaginous and bony components and an understanding of each component volume is essential in both functional and cosmetic surgery. Objectives We sought to radiographically measure septal dimensions on cross sectional computer tomography (CT) images, establishing average parameters for normal anatomy among a single, Caucasian population group. Methods One hundred and fifty consecutive sinus CT scan images were examined and 100 cases with appropriate sagittal views were included in the study. On each septum, the sagittal CT images were assessed and 14 points were identified and 23 lengths measured and tabulated. Trigonometric formulae were used to accurately calculate surface areas of 11 resulting triangles which constituted the components of the nasal septum. Results Measurements from 100 patients were included, with a mean age of 50.2 years, constituting 47 males and 53 females. Our surface area mapping established the following areas for both males and females respectively (mm2): quadrangular cartilage 1148 and 981; vomer 894 and 741; perpendicular plate of ethmoid bone 1244 and 1006; and total surface area 3287 and 2728. Our only statistically significant comparison in the series was found in the female series when age and reducing quadrilateral cartilage size were compared, highlighting reducing size with age (P = 0.04). Conclusions The study presents the largest published data series representing nasal septal measurements on CT images in a living Caucasian population. Our data demonstrates that septal size remains constant after adolescence, throughout our age-varied series (18-79 years), except in the female population where the quadrilateral cartilage reduces in size with age. Level of Evidence 4