Non-Invasive Determination of Bone Quality Markers by Monte Carlo Modeling and Optical Spectroscopy

总结： 骨质疏松症等骨脆性疾病需要进行骨质量监测，通常通过双X线检查进行。 X线吸收法（DXA）评估骨密度（BMD）。骨健康指数（BHI）和 掌骨指数（MCI）是基于骨的放射学几何评估的骨质量的其它量度。 从平面手X光片获得的掌骨。这些方法都使用电离辐射， 在某些人群中，这是一个令人担忧的问题，在资源匮乏的社区可能不容易获得。然而，X- 来自掌骨的X线数据已被证明是椎骨骨折风险的重要预测因素 和髋关节，并与DXA测定的BMD相关。在这里，我们建议开发一种替代方法 对于掌骨骨健康评估，近红外（NIR）光谱结合光纤 探针这是一种基于低能量非电离辐射的非侵入性方式， 与被评价材料或组织质量相关的分子信息。在目前的提案中， 骨质的NIR光谱分析将以多步骤方法进行优化。特定光学性质 将获得掌骨和覆盖的组织，然后用作Monte Carlo建模的输入 光子穿透皮肤和骨头的过程然后，这些数据将用于通知和优化 NIR光纤探头，使得所收集的光谱数据优先来自骨骼，而不是 覆盖组织。推进近红外光谱用于骨质量的临床评估将需要仔细 开发专用探针和光谱分析技术， 掌骨的测量。这种模式的发展最终可能导致发展 直接的，成本效益的方法，为社区筛查骨骼健康。

Summary: Diseases of bone fragility such as osteoporosis require bone quality monitoring, typically done by dual X- ray absorptiometry (DXA) assessment of bone mineral density (BMD). Bone health index (BHI) and metacarpal index (MCI) are other measures of bone quality based on radiographic geometric assessment of the metacarpal bones obtained from a planar hand X-ray. These approaches all use ionizing radiation, which is of concern in some populations, and may not be easily accessed in low-resource communities. Nevertheless, X- ray data from the metacarpal bones have been shown to be a significant predictor of fracture risk at the vertebrae and hip, and to correlate with DXA-determined BMD. Here, we propose development of an alternative approach for metacarpal assessment for bone health, near infrared (NIR) spectroscopy combined with a fiber optic probe. This is a non-invasive modality based on low energy non-ionizing radiation that can also yield molecular information related to the quality of material or tissue being evaluated. In the current proposal, NIR spectroscopic analysis of bone quality will be optimized in a multi-step approach. Specific optical properties of metacarpal bones and the overlying tissues will be obtained, and then used as input into Monte Carlo modeling of photon penetration through skin and bone. These data will then be used to inform and optimize the design of NIR fiber optic probes such that the spectral data collected preferentially comes from bone, as opposed to overlying tissues. Advancing NIR spectroscopy for clinical assessment of bone quality will require the careful development of application-specific probes and techniques for spectral analysis uniquely tailored for measurement of the metacarpal bone. Development of this modality could eventually lead to the development of straight-forward, cost effective approaches for community screening of bone health.