Cartilage Curvature Reshaping: A Quantitative Assessment

Horizontal mattress suturing is frequently performed during rhinoplasty and otoplasty procedures to control the curvature of the cartilages. Despite the popularity of this technique, there are no quantitative methods for determining the effects of mattress sutures in the cartilage reshaping.

The aim of this experimental study was to quantify the straightening effect of mattress suturing on the convexity of ear cartilage in a rabbit model.

Eleven young adult male New Zealand white rabbits were used in this study. A horizontal mattress suture with spacing 3 mm × 6 mm was placed in a rectangle demarcated on the left ear in the area with maximum convexity. Preoperative and postoperative photographs were taken before and immediately after surgery, respectively. The radius of curvature (ROC), the first-order derivative (FOD), and the second-order derivative (SOD) were calculated to quantify the net cartilage reshaping, the changes in each point, and the homogeneity of the newly shaped cartilage, respectively.

The mean ROCs were 1.112 cm and 2.169 cm before and after surgery, respectively, and this increase was statistically significant. The mean FOD for each point slope index was statistically lower after surgery (0.269 before surgery vs 0.135 after surgery). The mean SOD also significantly decreased after surgery (0.007 before surgery vs 0.003 after surgery). The values of the SOD remained positive after surgery, indicating that changes in the curvature were homogeneous.

A quantitative measurement method was introduced to directly quantify the controlling effect of a mattress suture. This method makes it possible to achieve the important task of comparing the effect of horizontal mattress suturing with that of other cartilage-reshaping techniques.