【作者】 蒋景英；

【导师】 虞启琏；

【作者基本信息】 天津大学 ， 生物医学工程， 2003， 博士

【摘要】 人体内各种化学成分是评价人体健康状况的重要信息，是多种疾病诊断与疗效判定的重要指标，及时检测这些化学成分含量十分重要。由于有创检测方法存在各种弊端，因此以近红外光谱检测技术为代表的无创检测方法成为国际上的研究热点之一。但是，诸多关键的共性问题限制了该方法的实际应用。本文以影响人体内成分无创光谱测量的关键因素—测量条件问题作为突破口，对近红外光谱测量中影响测量精度的测量条件问题进行了一系列深入的研究。本研究从理论分析着手，首次系统地研究基于人体内成分光谱检测的测量条件方法论及其构成要素；通过实验研究多种测量条件变化对光谱测量的影响，提出再现测量条件是提高近红外光谱稳定性和重复性的前提，探讨测量条件问题研究的必要性与重要性。为了消除或减小测量条件对人体内成分无创近红外光谱测量的影响，首次提出基于人体特征的测量条件再现原理，研制出智能化测量条件再现系统；该系统利用图像处理、接触压力测量等方法实现测头位置的确定，通过伺服定位装置实现测头的重复定位。该系统的精度分析和实验研究结果表明：测量条件再现系统的应用能大大减小测量位置及接触压力变化对光谱测量的影响，提高光谱测量的稳定性和重复性。针对上述测量条件再现系统中最佳初始接触压力确定问题，根据光纤测头与被测部位接触压力形成的特点，基于皮肤及皮下组织的生物力学特性，首次提出并建立了接触压力的有限元－蒙特卡罗模型（CP-F-M模型）；并将该模型的仿真结果和实验结果相结合，指导最佳初始接触压力值确定的实验方案设计。最后，针对测量条件再现系统应用效果分析，研制出无创人体血糖浓度近红外光谱测量系统，并开展了预临床实验研究。研究结果表明：应用测量条件再现系统可以减少甚至消除测量条件的改变而引起的测量误差；在应用测量条件再现系统的前提下，对所测得的近红外光谱进行一定的预处理后，将近红外光谱分析技术应用于无创血糖浓度测量是可行的。预临床实验结果展现出近红外光谱技术在无创人体内成分检测中有广阔的临床应用前景，本文的研究成果为该方法的成功实施奠定了理论和实验基础更多还原

【Abstract】 The various chemical components present in human body carry important information on health status. Such chemical information also serves as an important indicator to a number of clinical diagnostics and therapeutic effect. Therefore, timely analysis of these chemical concentrations has special meaning for modern health care. Invasive measurement is unfavorable when compared with non-invasive methods. Hence, Near-infrared spectroscopy receives global attention as a principal non-invasive diagnostic means.As a matter of fact, many key common issues severely constrain the practical application of this technique. This dissertation discusses the measurement conditions, which are primary factors affecting spectral measurement of human body composition, as a breakthrough to this problem. Measurement conditions affecting measuring accuracy in near-infrared spectral measurement are to be systematically discussed in details.In this dissertation, starting with theoretical analysis, we forward the methodology concerning body composition measurement conditions with spectroscopy methods as well as systematic description of its essential factors. Experiments are done to examine the influence of various measurement conditions on spectral measurement. It is concluded that reproducing measurement conditions is prerequisite to enhancing stability and repeatability in spectral measurement. A discussion of the necessity and importance of measurement conditions is also given.To eliminate or reduce the influence of measurement conditions on near-infrared spectral measurement of human body composition, measurement reproducing theory and smart system towards human body properties are put forwards originally. Image processing, and contact pressure measurement methods are employed to determine the position of probe in the system. Servo relocation device is utilized to relocate the probe position. Accuracy analysis and experimental results reveal that application of measurement conditions reproducing system can significantly reducing spectral difference arising from probe position and contact pressure. The stability and repeatability for spectra measurement can be improved accordingly. For the optimum initial contact pressure in the above measurement condition reproducing system, a contact pressure finite element monte carlo model is forwarded and constructed for the first time, which is based on the formation characteristics of contact pressure between optic fiber probe and the probing part as well as bio-mechanical properties of skin and subcutaneous tissue. Simulation results of the model are combined with experimental outcomes and serve as a guide to experimental design strategy to determine optimum initial contact pressure. Finally, non-invasive blood glucose concentration measurement system by near-infrared spectroscopy is set up according to effectiveness analysis of measuring conditions reproducing system. Clinical experiments are also conducted. Our study reveals: the application of measurement conditions reproducing system can reduce or even eliminate the measuring errors brought by measurement condition variation.<WP=6>With the application of measurement condition reproducing system, near-infrared spectroscopy technique proves to be feasible in blood glucose sensing after the NIR spectra undergo certain mathematical pretreatment. Pre-clinical experimental results demonstrate the great clinical prospect for near-infrared spectroscopy application in non-invasive human body composition analysis technique. Theory and experimental results disclosed by this dissertation laid solid basis for the successful application of this method更多还原