摘要
在活体成分无创测量中,人体组织的漫射光谱之间存在千差万别,即使同一组织的光谱也时刻发生着变化,这是影响活体组织成分测量精度的重要原因。通过漫射光谱实时监测组织的光学特性非常重要。由于漫射光的吸光度光谱沿光源-探测器距离不再呈现线性变化,不同距离下的测量结果不易相互借鉴,因此不宜采用单一距离的漫反射光测量方式。采用双光源-探测器距离的测量方式,通过差分测量获得了组织有效衰减系数,其与测量距离无关,是反映组织吸收、散射的综合光学参数。实验系统采用中心光纤入射,距中心0.6和2.0 mm的两个环状分布的光纤束接收漫反射光,并据此推测出被测组织的有效衰减系数。通过实时监测组织的有效衰减系数,可以监测组织的状态与成分变化信息。采用Intralipid脂肪乳作为组织仿体,考察了其中的葡萄糖浓度、血红蛋白浓度、颗粒密度、温度四个因素变化时在1000~1300 nm波段的有效衰减系数光谱,比较了它们的光谱特征。结果表明,有效衰减系数的光谱形状主要由介质的吸收变化决定。其中血红蛋白的有效衰减系数光谱显示出其在1000~1200 nm波段吸收显著,1200~1300 nm吸收减弱,这与血红蛋白的吸收特征一致;温度的光谱显示出与温度对水吸收光谱影响的光谱形状一致;葡萄糖与颗粒密度引起的有效衰减系数光谱相似,原因在1000~1300 nm波段葡萄糖吸收较弱,其主要影响介质散射特性。最后测量了不同人体的手指、手掌、手背、手臂外侧、手臂内侧的有效衰减系数光谱,比较了部位差异和个体差异。从人体光谱差异上很明显地看到了血红蛋白、散射特性不同引起的光谱差异。综上,提出的有效衰减系数光谱测量方法特别适用于活体组织的成分测量,为实时监测组织的散射、吸收变化提供了一条新途径。
In the tissue composition measurements in vivo based on diffuse spectroscopy,the tissue differences or variations could induce a big uncertainty.Monitoring the tissues’optical characteristics is necessary to improve the measurement accuracy.The measurement with single light source detector separation(SDS)is not suitable to be applied widely because the absorbance of diffuse light dose not vary with SDSs linearly then.The results with one SDS hardly are transferred to that with other SDSs.In this paper,we use two SDSs to perform a differential measurement and acquire the effective attenuation coefficient(EAC)for in vivo tissues,independent of the used SDSs as a comprehensive optical property related to tissue absorption and scattering.An optical fiber leads incident light,and two detectors are designed for the two SDSs,arranged circularly with multiple optical fibers.The SDSs applied are 0.6 and 2.0 mm,respectively.The acquired EAC spectra can monitor the tissue composition variations or tissue condition fluctuations.In tralipid solutions were used to mimic tissues,and the EAC spectra of glucose concentration,hemoglobin concentration,particle density and temperature in the waveband of 1000~1300 nm were investigated and compared.The results show that the EAC spectra mainly demonstrate the tissue absorption caused by the variables.The EAC spectra of hemoglobin show a similar characteristic with hemoglobin’s absorption as there is a more considerable absorption at 1000~1200 nm and a lower at 1200~1300 nm.The EAC spectra caused by temperature changes appear similar to the water’s absorption change under varying temperatures.The EAC spectra caused by scattering change show less specificity,and the spectra of glucose and particle density seem similar in that they only affect scattering as glucose has less absorption at this waveband.Furthermore,the EAC spectra of human bodies are investigated and their differences between individuals or test positions,including fingers,palms,backs of hands,and lateral arms.These E
作者
刘瑾
付润娟
韩同帅
刘蓉
孙迪
LIU Jin;FU Run-juan;HAN Tong-shuai;LIU Rong;SUN Di(State Key Laboratory of Precision Measuring Technology and Instruments,Tianjin University,Tianjin 300072,China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2022年第9期2746-2751,共6页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(81971657,81871396)资助。
关键词
近红外光谱
有效衰减系数
活体组织
无创成分测量
血红蛋白
血糖
温度
Near-infrared spectroscopy
Effective attenuation coefficient
In vivo tissue
Noninvasive composition measurement
Hemoglobin
Blood glucose
Temperature
