Abstract:
Accurate and precise body composition estimates, notably of total body adiposity, are a vital component of in vivo physiology and metabolic studies. The reference against which other body composition approaches are usually validated or calibrated is the family of methods referred to as multicomponent \"body density\" models. These models quantify three to six components by combining measurements of body mass, body volume, total body water, and osseous mineral mass. Body mass is measured with calibrated scales, volume with underwater weighing or air-displacement plethysmography, total body water with isotope dilution, and osseous mineral mass by dual-energy X-ray absorptiometry. Body density is then calculated for use in model as body mass/volume. Studies over the past decade introduced a new approach to quantifying body volume that relies on dual-energy X-ray absorptiometry measurements, an advance that simplifies multicomponent density model development by eliminating the need for underwater weighing or air-displacement plethysmography systems when these technologies are unavailable and makes these methods more accessible to research and clinical programs. This review critically examines these new dual-energy X-ray approaches for quantifying body volume and density, explores their shortcomings, suggests alternative derivation approaches, and introduces ideas for potential future research studies.
摘要:
准确和精确的身体成分估计,特别是全身肥胖,是体内生理和代谢研究的重要组成部分。通常验证或校准其他身体成分方法的参考是称为多组分“身体密度”模型的方法系列。这些模型通过结合体重测量来量化三到六个分量,身体体积,全身水,和骨质矿物质。体重是用校准的秤测量的,使用水下称重或空气置换体积描记术,同位素稀释的全身水,通过双能X射线吸收法和骨矿物质质量。然后计算身体密度以在模型中用作体重/体积。过去十年的研究引入了一种新的方法来量化身体体积,该方法依赖于双能X射线吸收法测量,通过在这些技术不可用时消除对水下称重或空气位移体积描记术系统的需要,简化了多组分密度模型开发,并使这些方法更易于研究和临床计划。这篇综述严格地研究了这些用于量化身体体积和密度的新的双能X射线方法,探索他们的缺点,建议替代推导方法,并介绍了潜在的未来研究的想法。