In this study, we investigated the feasibility of using photoacoustic time-frequency spectral analysis (PA-TFSA) for evaluating the bone mineral density (BMD) and bone structure. Simulations and ex vivo experiments on bone samples with different BMDs and mean trabecular thickness (MTT) were conducted. All photoacoustic signals were processed using the wavelet transform-based PA-TFSA. The power-weighted mean frequency (PWMF) was evaluated to obtain the main frequency component at different times. The y-intercept, midband-fit, and slope of the linearly fitted curve of the PWMF over time were also quantified. The results show that the osteoporotic bone samples with lower BMD and thinner MTT have higher frequency components and lower acoustic frequency attenuation over time, thus higher y-intercept, midband-fit, and slope. The midband-fit and slope were found to be sensitive to the BMD; therefore, both parameters could be used to distinguish between osteoporotic and normal bones (p < 0.05).

在本研究中，我们研究了使用光声时频光谱分析（PA-TFSA）评估骨矿物质密度（BMD）和骨结构的可行性。对具有不同 BMD 和平均小梁厚度 (MTT) 的骨样品进行了模拟和离体实验。所有光声信号均使用基于小波变换的 PA-TFSA 进行处理。评估功率加权平均频率（PWMF）以获得不同时间的主频率分量。还对 PWMF 随时间变化的线性拟合曲线的y 截距、中带拟合和斜率进行了量化。结果表明，具有较低 BMD 和较薄 MTT 的骨质疏松骨样品随着时间的推移具有较高的频率分量和较低的声频衰减，因此具有较高的y 截距、中带拟合和斜率。发现中带拟合和斜率对 BMD 敏感；因此，这两个参数均可用于区分骨质疏松骨骼和正常骨骼 ( p < 0.05)。