In vivo oxygen tension in human septal cartilage increases with age

Abstract

Objectives/hypothesis: Tissue-engineered septal cartilage may provide a source of autologous cartilage for repair of nasal defects. Production of clinically useful neocartilage involves multiple steps that include manipulating the culture environment. Partial pressure of oxygen (ppO(2) ) is a property that has been shown to influence cartilage development. Specifically, studies suggest low ppO(2) augments in vitro growth of articular cartilage. Although in vivo measurements of articular cartilage ppO(2) have demonstrated hypoxic conditions, measurements have not been performed in septal cartilage. The objective of this study was to determine the ppO(2) of septal cartilage in vivo.

Study design: Prospective, basic science.

Methods: The ppO(2) was measured in 14 patients (mean ± standard deviation age, 35.9 ± 14.5 years; range, 18-63 years) during routine septoplasty or septorhinoplasty using the OxyLab pO(2) monitor (Oxford Optronix Ltd., Oxford, UK). Measurements were taken from the septum and inferior turbinate. Each patient's age and sex were recorded.

Results: The average ppO(2) measured at the septum and inferior turbinate was 10.5 ± 10.1 mm Hg (1.4 ± 1.3%) and 27.6 ± 12.4 mm Hg (3.6 ± 1.6%), respectively. The ppO(2) of these locations was significantly different (P < .005). Advancing age was positively correlated with septal ppO(2) (R(2) = 0.42; P < .05). Septal ppO(2) showed no significant sex variation.

Conclusions: This is the first report of in vivo measurement of ppO(2) in septal cartilage. The data demonstrate reduced oxygenation of septal cartilage relative to the inferior turbinate. This elucidates an important characteristic of the in vivo milieu that can be applied to septal cartilage tissue engineering.

Fig. 1

OxyLab needle probe inserted into the inferior portion of the septal cartilage adjacent to the maxillary crest.

Fig. 2

Relationship of septal partial pressure of oxygen (ppO₂₎ and patient age. The regression line and corresponding R² value is shown. There was a significant correlation between advancing age and septal ppO (R² = 0.42; P < .05).