Development of portable near-infrared muscle oximeter using multi-sensor method.

研制了一种基于双波长近红外光谱和多个光电传感器的便携式组织血氧仪，用于肌肉氧合的实时、动态测量。该血氧仪可以消除组织结构不均匀对测量的影响，可用于运动和康复医学领域以及肌肉组织生理学领域中肌肉氧合的定量评价。便携式组织血氧仪的研制：采用LED作为光源，使血氧仪结构紧凑，便于动态测量。在距光源20 mm、30 mm和40 mm的距离放置光电传感器，测量不同脂肪层厚度的肌肉的氧合。根据光扩散理论和组织体模实验，通过对反射率的系统分析，确定了一种获得氧合的算法。…影响的校正更多的皮肤脂肪层和皮肤：通过蒙特卡洛模拟、体模实验和活体测量，系统地研究了皮下脂肪层的影响。建立了测量灵敏度因脂肪层的存在而降低的修正方法。还研究了皮肤和皮肤血流的影响，发现可以使用距离光源3 mm的附加近旁光电传感器来消除这些影响。实际应用评估：为了评估所开发系统的有效性，对11名北欧奥运会运动员的肌肉组织氧传输能力进行了测量。组织光学特性的活体测量：作为确定平均光学路径长度和获得绝对血氧值的基础数据，使用时间分辨光谱在前臂成功地测定了肌肉组织的光学特性，而不受脂肪层的影响。较少

A portable tissue oximeter based on two-wavelength near-infrared spectroscopy with multiple photo sensors was developed for a real-time, ambulatory measurement of muscle oxygenation. This oximeter can eliminate the influences of inhomogeneous structure of tissues on the measurement and is useful for quantitative evaluation of muscle oxygenation in the fields of sports and rehabilitation medicine as well as in muscle tissue physiology. Important results of this study are summarized as follows.Development of the portable tissue oximeter : The oximeter was made compact for the ambulatory measurement using LED as a light source. Photo sensors were placed at distances of 20, 30 and 40 mm from the light source for the oxygenation measurement of the muscle with various thicknesses of fat layers. An algorithm for obtaining oxygenation was determined by systematic analyses of reflectance, based on the light diffusion theory and tissue phantom experiments.Correction of the influences of a subcut … More aneous fat layer and the skin : Influence of a subcutaneous fat layer was systematically examined through Monte Carlo simulation, phantom experiments and in vivo measurements. A correction method for decrease in measurement sensitivity due to the presence of a fat layer was established. Effects of the skin and skin blood flow were also studied, and it was found that these effects can be eliminated using an additional near-by photo sensor 3 mm distant from the light source.Evaluation of the system in practical applications : To evaluate the usefulness of the developed system, oxygen transport capacity in the muscle tissue was measured in eleven Olympic athletes of the Nordic combined. Measured transport capacities were clearly higher than those of untrained subjects.In vivo measurement of tissue optical properties : As basic data for determining a mean optical pathlength and for obtaining an absolute oxgenation value, optical properties of muscle tissues were successfully determined at the forearm, without the influence of a fat layer, using time-resolved spectroscopy. Less