Histological structure of the nasal cartilages and their perichondrial envelope. I. The septal and lobular cartilage.

The cellular elements and extracellular matrix of the nasal septal cartilage and the lateral crus of the lobular cartilage were studied in serial coronal sections of five human cadaver noses. To discern the various tissue components, the sections were stained according to the methods of Mallory-Cason, Azan, Herovici, Verhoeff-van Gieson, and Lawson as well as by immunohistochemistry to demonstrate the presence of collagen type I and II. A characteristic gradual transition of the chondrocytes was observed in both septal and lobular cartilage: from numerous small flat cells oriented parallel to the surface of the cartilage to less numerous larger ovaloid cells oriented perpendicular to the surface. This difference between the peripheral and central zones of the cartilage was particularly marked in lobular cartilage. Both septal and lobular cartilage have a high density of type II collagen but almost none of type I. The peripheral zones of the matrix showed a higher density of collagen than the central zone. This difference was more pronounced in septal than lobular cartilage. The high density of type II collagen in septal cartilage, particularly in the peripheral zones, suggests that one of the primary tasks of the septum is providing stiffness to the external nose. That idea is consistent with findings from our study of the perichondrial envelope.