Burmeister J J, Arnold M A
Department of Chemistry and Optical Science and Technology Center, University of Iowa, Iowa City, IA 52242, USA.
Clin Chem. 1999 Sep;45(9):1621-7.
Six putative measurement sites were evaluated for noninvasive sensing of blood glucose by first-overtone near-infrared spectroscopy. The cheek, lower lip, upper lip, nasal septum, tongue, and webbing tissue between the thumb and forefinger were examined. These sites were evaluated on the basis of their chemical and physical properties as they pertain to the noninvasive measurement of glucose. Critical features included the effective optical pathlength of aqueous material within the tissue and the percentage of body fat within the optical path. Aqueous optical paths of 5 mm are required to measure clinically relevant concentrations of glucose in the first-overtone region. All of the tested sites met this requirement. The percentage of body fat affects the signal-to-noise ratio of the measurement and must be minimized for reliable glucose sensing. The webbing tissue contains a considerable amount of fat tissue and is clearly the worse measurement site. All other sites possess substantially less fat, with the least amount of fat in tongue tissue. For this reason, the tongue provides spectra with the highest signal-to-noise ratio and is, therefore, the site of choice on the basis of spectral quality.
通过一次谐波近红外光谱法对六个假定的测量部位进行了无创血糖传感评估。检查了脸颊、下唇、上唇、鼻中隔、舌头以及拇指和食指之间的蹼状组织。根据这些部位与葡萄糖无创测量相关的化学和物理特性对其进行了评估。关键特征包括组织内水性物质的有效光程长度以及光程内体脂的百分比。在一次谐波区域测量临床相关浓度的葡萄糖需要5毫米的水性光程。所有测试部位均满足这一要求。体脂百分比会影响测量的信噪比，为了实现可靠的葡萄糖传感，必须将其降至最低。蹼状组织含有大量脂肪组织，显然是最差的测量部位。所有其他部位的脂肪含量都要少得多，舌头组织中的脂肪量最少。因此，舌头提供的光谱信噪比最高，因此，基于光谱质量，舌头是首选部位。
