The Clinical Analysis of the Nasal Septal Cartilage by Measurement Using Computed Tomography

BACKGROUND: The nasal septal cartilage is often used as a donor graft in rhinoplasty operations but can vary widely in size across the patient population. As such, preoperative estimation of the cartilaginous area is important for patient counseling as well as operating planning. We aim to estimate septal cartilage area by using facial computed tomography (CT) studies. METHODS: The study was performed using facial CT images taken from 200 patients between January 2012 to July 2015. Using the mid-sagittal image, the boundary of cartilaginous septum was delineated from soft tissue using the mean difference in signal intensity (or brightness). The area within this boundary was calculated. The calculated area for septal cartilage was then compared across age groups and sexes. RESULTS: Overall, the mean area of nasal septal cartilage was 8.18 cm(2) with the maximum of 12.42 cm(2) and the minimum of 4.89 cm(2). The cartilage areas were measured to be larger in men than in women (p<0.05). The area decreased with advancing age (p<0.05). CONCLUSION: Measuring the size of septal cartilage using brightness difference is more precise and reliable than previously reported methods. This method can be utilized as the standard for prevention of postoperative complication.