Morphologic and histologic changes of the septal cartilage after cross-hatching incision

Abstract

Introduction: In septoplasty, cross-hatching incision to release the internal locking of the curved cartilage has the potential to weaken the structural support of cartilaginous septum. This study evaluated the morphological and histological changes of septal cartilage after flap elevation and full thickness cross-hatching incision.

Methods: Twenty five mature New Zealand white rabbits were categorized into five groups according to the procedures they received: unilateral mucoperichondrial flap (MPF) elevation without cross-hatching incisions (CHI) group (unilateral MPF group, N = 5)

unilateral MPF elevation with cross-hatching incisions group (unilateral MPFcCHI group, N = 5)

bilateral MPF elevation without cross-hatching incisions group (bilateral MPF group, N = 5)

bilateral MPF elevation with cross-hatching incisions group (bilateral MPFcCHI group , N = 5)

no MPF elevation and no cross-hatching incisions group (control group, N = 5). In each group, the subjects were sacrificed 3 months after the procedure. Thickness was measured and histological changes of chondrocyte and extracellular matrix were evaluated using hematoxylin and eosin, Massons trichrome stain, Alcian blue, and Verhoeffs elastic stain.

Results: Thickness was about the same in all groups. Histologic examination revealed that the chondrocyte numbers and dystrophic feature as well as the ratio of chondroblast were not different among the 5 groups. Massons trichrome stain and Verhoeff's elastic stain showed no difference among the 5 groups (p=0.304, p=0.417). Alcian blue stain showed that bilateral MPF with/without CHI groups and CHI groups with/without MPF elevation showed lower expression of proteoglycan than the other groups (p=0.005).

Conclusion: Bilateral MPF elevation or cross-hatching incisions may decrease the deposition of proteoglycan in the extracellular matrix while maintaining the same chondrocyte cellularity, collagen fiber, and cartilage thickness.