Smartphone-Based SpO2 Measurement by Exploiting Wavelengths Separation and Chromophore Compensation
Smartphone-Based SpO2 Measurement by Exploiting Wavelengths Separation and Chromophore Compensation
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DOI：
10.1145/3360725
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发表时间：
2020-02-01
影响因子：
4.1
通讯作者：
Tam Vu
中科院分区：
文献类型：
--
作者：
Nam Bui;Anh Nguyen;Tam Vu
呼吸道疾病的患者需要频繁而准确的血氧水平监测。但是，现有技术要么需要专用硬件，要么无法预测较低的饱和度。为了填补这一空白，我们使用相机和手电筒功能提出了一个基于电话的氧气估计系统，称为PHO2，这些功能很容易在当今的现成智能手机上获得。由于手机的摄像头和手电筒不是为此目的而制造的，因此将它们用于氧气水平估算带来许多困难。我们引入了一个具有成本效益的附加组件以及一组用于空间和光谱光学信号调制的算法，以放大感兴趣的光学信号，同时最大程度地减少噪声。还提出了一种基于近场的压力检测和反馈机制，以减轻测量过程中用户行为的负面影响。我们还采用了一种非线性引用模型，该模型具有异常取消技术，该技术允许Pho2从智能手机相机产生的颜色强度比准确估计氧气水平。对六个主题的COTS智能手机的评估表明，Pho2可以在3.5％的误差速率中估计与FDA-FDA-apprave oppry appry oximeTry compimetry相比，pho2可以估计氧气饱和度。此外，我们在医院的评估与由0.83/1.0 Kendall Tau系数合格的地面真相相关。
Patients with respiratory diseases require frequent and accurate blood oxygen level monitoring. Existing techniques, however, either need a dedicated hardware or fail to predict low saturation levels. To fill in this gap, we propose a phone-based oxygen level estimation system, called PhO2, using camera and flashlight functions that are readily available on today's off-the-shelf smartphones. Since the phone's camera and flashlight were not made for this purpose, utilizing them for oxygen level estimation poses many difficulties. We introduce a cost-effective add-on together with a set of algorithms for spatial and spectral optical signal modulation to amplify the optical signal of interest while minimizing noise. A near-field-based pressure detection and feedback mechanism are also proposed to mitigate the negative impacts of user's behavior during the measurement. We also derive a non-linear referencing model with an outlier removal technique that allows PhO2 to accurately estimate the oxygen level from color intensity ratios produced by the smartphone's camera.An evaluation on COTS smartphone with six subjects shows that PhO2 can estimate the oxygen saturation within 3.5% error rate comparing to FDA-approved gold standard pulse oximetry. In addition, our evaluation in hospitals presents high correlation with ground-truth qualified by the 0.83/1.0 Kendall tau coefficient.