Development of a noninvasive multi-detector tissue reflectance oximeter

无创多探测器组织反射血氧计的研制

• 批准号: 08408038
• 负责人: TAKATANI Setsuo
• 金额: $ 19.65万
• 依托单位: Tokyo Medical and Dental University (1999)Yamagata University (1996-1998)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08408038/
• 关键词: Reflectance Pulse Oximetry; Whole blood oximetry; Tissue Reflectance Oximetry; Hemoglobin Content; hemoglobin Oxygen Saturation; Multi-array optical sensor; 反射光パルスオキシメータ; 光散乱; 光吸収; 反射型パルスオキシメータ; ホトダイオード; 発光ダイオード; 多層組織モデル; 光子拡散理論; 人工心臓; オキシメ

(1) A hybrid reflectance sensor consisting of light emitting diode (LED) and photodiode (PD) for measurement of hemoglobin content (Hb) and oxygen saturation (SOィイD22ィエD2) of whole blood was designed using the 3-dimensional photon diffusion theory. Wavelengths selected included 660, 730 and 830nm and separation distance between the LED and PD was 2.1mm to optimize the linearity in hematocrit measurement at 830nm. The sensor was evaluated using the fresh bovine blood. For Hb measurement, the reflectance at 830nm yielded the standard error of 3.37%. As for SOィイD22ィエD2 accuracy over 30-100% range, the combination of 730/830 wavelength yielded better results than 660/830 wavelength pair, with the standard error of 4.24%.(2) Secondly, the 3-dimensional photon diffusion theory was utilized to design a reflectance pulse oximeter sensor for improved accuracy over a wider SOィイD22ィエD2 range. In order to attain this goal, selection of wavelength pair and sensor geometry were examined theoreticall … More y. A new sensor incorporated wavelengths of 730 and 880nm and 10 LED chips for each wavelength were placed at equal distance of 7mm around the photodiode. The separation distance of 7mm was selected to maximize the pulsatile signal to background signal level. Initially, the sensor was evaluated in dogs ; the arterial SOィイD22ィエD2 was varied through controlling the oxygen content of the air breathed. The reflectance sensor was attached to the internal lining of the mounth and its signals were compared against the arterial blood sample data analyzed separately. The 730/880nm sensor showed better accuracy in comparison with the 660/910nm sensor with the standard error of 2.69%. In 30 human volunteers, reflectance measurements were made from finger-tip, forehead and chest wall. The pulsatile signal level from the forehead was approximately 30% of the finger-tip and that of the chest was about 10%. The pulsatile signal level at 730nm was largest in comparison to other wavelengths at any location. Clinical evaluation of the sensor was carried out in 6 volunteers. The reflectance measurements from the forehead were compared against the arterial blood samples obtained from the radial artery during controlled ventilation. The 730/880nm sensor showed the standard error of 4.2% in comparison to 6.3% of 660/910nm sensor. Continuous monitoring of the patients with 730/880 sensor in the operating room revealed stable and reliable performance than 660/910 sensor over 6-8 hour duration.(3) Thirdly, two layer tissue model was constructed with the lower layer being diluted whole blood (hematocrit 14%) and upper layer being non-blood tissue element. The thickness of the non-blood tissue element was varied from 0 to 6mm, while the reflectance from the compound tissue model was measured using a multi-array photodiode sensor consisting of 46 elements with 1mm pitch. The separation distance between the light source and detector in the multi-array sensor was adjustable from 12.5 to 60mm. The same wavelengths used in whole blood study were also employed in this study and the SOィイD22ィエD2 was derived from the ratio of the two wavelengths using a linear regression equation. The effect of non-blood element thickness resulted in decrease of sensitivity to SOィイD22ィエD2 variation. With the increase in tissue thickness, the larger separation distance sensor resulted in better measurement sensitivity. Provided that the tissue thickness is know, the detection of deeper layer SOィイD22ィエD2 may be derived from the surface of the tissue model. It is suggested that through proper design of sensor geometry 3-dimensional detection of oxygen content inside the tissue will become possible. Less

(1)基于三维光子扩散理论，设计了一种由发光二极管（LED）和光电二极管（PD）组成的混合反射式传感器，用于测量全血中的血红蛋白（Hb）含量和血氧饱和度（SO_（22））。选择的波长包括660、730和830 nm，LED和PD之间的间距为2.1mm，以优化在830 nm处测量红细胞压积的线性。使用新鲜牛血对传感器进行评价。对于Hb测量，在830 nm处的反射率产生3.37%的标准误差。对于30%-100%范围内的SO_（22）_（22）_（22）准确度，730/830波长的组合产生的结果优于660/830波长对，标准误差为4.24%。(2)其次，利用三维光子扩散理论设计反射式脉搏血氧仪传感器，以在更宽的SOイD22 D2范围内提高准确度。为了达到这一目标，从理论上研究了波长对的选择和传感器的几何结构 ...更多信息 y.一种新的传感器结合了730和880 nm的波长，每个波长的10个LED芯片被放置在光电二极管周围7 mm的相等距离处。选择7 mm的间隔距离以使脉动信号最大化至背景信号水平。最初，在犬中评价传感器;通过控制呼吸空气的氧含量来改变动脉SO_（22）_（22）_（22）。将反射传感器连接到mounth的内衬，并将其信号与单独分析的动脉血样数据进行比较。与660/910 nm传感器相比，730/880 nm传感器显示出更好的准确性，标准误差为2.69%。在30名志愿者中，从指尖、前额和胸壁进行反射率测量。来自前额的脉动信号水平约为指尖的30%，来自胸部的脉动信号水平约为指尖的10%。与任何位置的其他波长相比，730 nm处的脉动信号水平最大。在6名志愿者中对传感器进行了临床评价。前额的反射率测量值与在受控通气期间从桡动脉获得的动脉血样本进行比较。730/880 nm传感器的标准误差为4.2%，而660/910 nm传感器的标准误差为6.3%。在手术室中使用730/880传感器对患者进行连续监测，结果表明，在6-8小时的持续时间内，730/880传感器的性能比660/910传感器稳定可靠。(3)第三，构建两层组织模型，下层为稀释的全血（红细胞压积14%），上层为非血液组织成分。非血液组织元素的厚度从0到6 mm变化，而来自复合组织模型的反射率使用由46个元素组成的具有1 mm间距的多阵列光电二极管传感器来测量。多阵列传感器中光源与检测器之间的间距在12.5至60 mm之间可调。在本研究中还采用了全血研究中使用的相同波长，并且使用线性回归方程从两个波长的比值推导出SO λ D22 λ D2。非血液元素厚度的影响导致对SO_（22）D_2变异的敏感性降低。随着组织厚度的增加，较大的分离距离传感器导致更好的测量灵敏度。假设组织厚度是已知的，则可以从组织模型的表面导出对较深层S 0的检测。有人建议，通过适当的传感器几何形状的设计，三维检测组织内的氧含量将成为可能。少

项目成果

野川雅道、高谷節雄他: "反射型パルスオキシメトリーの拡散理論による検討および計測部位による脈波成分分布について"医用電子と生体工学. 36特別. 271 (1998)

Masamichi Nokawa、Setsuo Takatani 等人：“基于扩散理论的反射型脉搏血氧测定法和脉搏波成分随测量部位的分布”，《医疗电子与生物工程》36 Special（1998）。

Kaiwa T, Takatani S, et al.: "Optical method as applied for detection of blood hematocrit inside the magnetically suspended centrifugal blood pump"Jap Artificial Organs. 28. 173-177 (1999)

Kaiwa T、Takatani S 等人：“用于检测磁悬浮离心血泵内血细胞比容的光学方法”Jap Artificial Organs。

野川雅道、高谷節雄 他: "臨床応用を目指した反射型パルスオキシメトリの多層モデルの影響"医用電子と生体工学. 37 特別号. 199 (1999)

Masamichi Nokawa、Setsuo Takatani 等人：“反射脉搏血氧饱和度多层模型对临床应用的影响”《医疗电子与生物工程》37 号特刊（1999 年）。

Kaiwa T,Takatani S et al: "Measurement of blood hematocrit inside the magnetically suspended centrifugal pump using an optical technique" Artificial Organs. (in press). (1999)

Kaiwa T、Takatani S 等人：“使用光学技术测量磁悬浮离心泵内的血细胞比容”人工器官。

Nogawa M,Takatani S, et al.: "A new hybrid reflectance pulse oximeter sensor for lower saturation measurement and broader clinical application"Proc. Of SPIE. 2976. 78-87 (1997)

Nokawa M、Takatani S 等人：“一种新型混合反射式脉搏血氧计传感器，用于更低的饱和度测量和更广泛的临床应用”Proc。