Human nasal cartilage ultrastructure: characteristics and comparison using scanning electron microscopy.

OBJECTIVES/HYPOTHESIS Human nasal cartilage is hyaline cartilage, although the function and loads placed on it are different depending on the location. We hypothesized that important differences exist between the nasal septal cartilage and lower lateral cartilage (LLC) ultrastructures. Such differences would be important in the field of cartilage engineering. METHODS Ten specimens (6 septum and 4 LLC) of cartilage from patients undergoing nasal surgery (rhinoplasty or septoplasty) were obtained and examined using scanning electron microscopy. Micrographs were then analyzed and measured using photograph analysis software. RESULTS The collagen fibers of septal cartilage were found to be arranged in a mesh framework, with larger lacunae and thicker fibers measuring 3.18 microm (standard deviation = 0.75 microm), with a 99.9% confidence interval of 2.74 to 3.54 microm. LLC fibers, on the other hand, were arranged in less-organized sheets, with fibrous extensions, and had fewer, narrower lacunae. The fibers from the LLC averaged 2.29 microm, with a 99.9% confidence interval of 1.17 to 3.42 microm. CONCLUSIONS Significant ultrastructural differences exist between the cartilage of the nasal septum and LLC. These are almost certainly the result of their embryologic origins and different forces placed on the structures they support. A less-organized pattern with smaller collagen fibers is present in the LLC versus the more-organized, layered, thicker collagen fibers of the septum. These differences may prove to be critical in the future of cartilage engineering.