基于复阻抗咽造影的吞咽事件检测与智能识别方法

吞咽障碍早期筛查是降低吞咽障碍发病率的重要手段，而对吞咽事件(SE)的准确识别是吞咽障碍筛查和治疗过程中的关键环节。阻抗咽造影(IPG)是一种新型非侵入式吞咽事件检测方法，但现有的IPG技术仅检测阻抗幅值而忽略了同样重要的相位信息。为了实现对吞咽事件的全面检测及智能识别，该文提出一种基于整周期数字锁相放大原理的复阻抗咽造影(CIPG)检测方法，设计了基于FPGA的CIPG检测系统以连续描记吞咽过程的复阻抗(阻抗幅值和相位)信息，并设计了基于连续小波变换(CWT)和GoogLeNet相结合的吞咽事件智能识别算法。设计了包含喝水、干咽、吃面包、吃酸奶、咳嗽等5种吞咽事件的识别实验，实验结果表明，仅利用阻抗幅值信息时的吞咽事件识别准确率为86.1%，而同时利用阻抗幅值和相位信息时的识别准确率为95.7%，后者的识别准确率高于其它算法。该研究证实了CIPG技术和吞咽事件智能识别算法的有效性与优越性，为下一步开发基于CIPG的吞咽障碍早期筛查方法奠定了理论和技术基础。

Detection and Intelligent Recognition Method of Swallowing Events Based on Complex Impedance Pharyngography

Early screening of dysphagia is an important means to reduce the incidence of dysphagia, and accurate identification of Swallowing Events (SE) is a key step in the screening and treatment of dysphagia. Impedance PharyngoGraphy (IPG) is a new non-invasive SE detection method, but the existing IPG technique only detects the impedance amplitude and ignores the equally important phase information. Aiming to comprehensively extracting and intelligently recognizing SE, a Complex Impedance PharyngoGraphy (CIPG) detection method based on integer-period digital lock-in amplifying principle is proposed, and a CIPG measurement system is designed based on FPGA to continuously record the complex impedance (amplitude and phase) information during swallowing process, and an SE intelligent recognition algorithm based on Continuous Wavelet Transform (CWT) and GoogLeNet is designed. A five-SE recognition experiment including drinking water, dry swallowing, eating bread, eating yogurt and coughing is designed. The experimental results show that the SE recognition accuracy is 86.1% when only using impedance amplitude information, and 95.7% when using both impedance amplitude and phase information. The latter SE recognition accuracy is higher than that of other algorithms. This study confirms the effectiveness and superiority of CIPG technology and SE intelligent recognition algorithm, and lays a theoretical and technical foundation for further developing an early screening method of dysphagia based on CIPG.