Discipline of Physics, Queensland University of Technology, GPO Box 2434, Brisbane, QLD, 4001, Australia.
Eur Biophys J. 2011 Jan;40(1):81-91. doi: 10.1007/s00249-010-0629-4. Epub 2010 Oct 23.
We used Monte Carlo simulations of Brownian dynamics of water to study anisotropic water diffusion in an idealised model of articular cartilage. The main aim was to use the simulations as a tool for translation of the fractional anisotropy of the water diffusion tensor in cartilage into quantitative characteristics of its collagen fibre network. The key finding was a linear empirical relationship between the collagen volume fraction and the fractional anisotropy of the diffusion tensor. Fractional anisotropy of the diffusion tensor is potentially a robust indicator of the microstructure of the tissue because, to a first approximation, it is invariant to inclusion of proteoglycans or chemical exchange between free and collagen-bound water in the model. We discuss potential applications of Monte Carlo diffusion-tensor simulations for quantitative biophysical interpretation of magnetic resonance diffusion-tensor images of cartilage. Extension of the model to include collagen fibre disorder is also discussed.
我们使用布朗动力学的蒙特卡罗模拟来研究关节软骨理想模型中的各向异性水扩散。主要目的是将模拟作为一种工具，将水扩散张量的分数各向异性转化为软骨中胶原纤维网络的定量特征。主要发现是胶原体积分数与扩散张量的分数各向异性之间存在线性经验关系。扩散张量的分数各向异性可能是组织微观结构的一个稳健指标，因为在第一近似下，它不受模型中蛋白聚糖的包含或游离水与胶原结合水之间的化学交换的影响。我们讨论了蒙特卡罗扩散张量模拟在软骨磁共振扩散张量图像定量生物物理解释中的潜在应用。还讨论了将模型扩展到包括胶原纤维无序的问题。
