ABSTRACT
Objective To study the feasibility of the measurement of the thickness of rabbit knee joint cartilage by comparing the optical coherence tomography (OCT)and the undecalcified frozen section method on respectively measure the thickness of New Zeal-and white rabbit’s knee cartilage.Methods 50 standardized cultivation,adult and male New Zealand white rabbits (100 knees) were selected in this study.The measurement point was at the knee weight-bearing area of the medial femoral condyle with a 2 milli-meter diameter trephine,and the cartilage thickness data at the same center point and ±0.5 mm from the center were obtained.OCT and freeze-sectioning method were adopted at each site,respectively.The difference between OCT and histological method was com-pared and Bland-Altman plot was constructed.Results The thickness results of the center,+0.5 mm,-0.5 mm points were (296.5± 1.6)μm,(302.6± 3.5)μm,(287.9±5.6)μm by OCT,(278.4±1.9)μm,(290.3±5.9)μm,(280.3±4.6)μm by freeze-sectio-ning method,respectively.In Bland-Altman diagram,mean difference and 95% confidence interval were 18.1 1 (1 6.65,1 9.56)μm, 12.4 (5.5,1 9.2)μm,7.4 (2.8,12.0)μm.Intra-class correlation coefficients(ICC)for resemblance between the 2 techniques were 0.93(95%CI:0.89-0.95,P <0.000 1),0.84(95%CI:0.77-0.89,P <0.000 1),0.91(95%CI:0.87 -0.94,P <0.000 1),respec-tively.Conclusion As compared with the measurement of undecalcified frozen section,OCT for the rabbits’knee joint cartilage thickness measurement is feasible with the advantages of noninvasiveness,good repeatability.OCT can provide data reference in ani-mal experiments of cartilage tissue engineering for articular cartilage defect repair.