Dynamic Coupled Physical Field Modeling of a Flexible Balloon-Catheter System Using a Piezoelectric Sensing Array Under Simulated Esophageal Peristalsis

In this study, we focused on addressing the challenges existing in diagnostic techniques for esophageal motility dysfunction, specifically addressing the limitations of high-resolution manometry (HRM) and luminal functional imaging probes (FLIPs). We designed an innovative balloon-catheter structure based on a flexible piezoelectric sensor array for esophageal motility detection and simulated the swallowing process on an isolated porcine esophageal tube, resulting in precise monitoring of pressure changes at key points of the esophagus. The experimental results reveal the effectiveness of the sensor system in monitoring the pressure changes at key points of the esophagus, showing good accuracy and sensitivity. In this study, the performance of the sensor system under different environmental conditions is explored in depth by combining simulation, analytical calculation, and physical experiments. The application of finite element simulation and feature analysis successfully established the direct relationship between the esophageal pressure and the sensor output and realized the accurate reconstruction of the esophageal peristaltic wave pressure. At the theoretical and experimental level, the analysis of the sensor unit verifies its efficient response to resting and principal characteristic peristaltic waves. The spatial and temporal distribution of the sensor output is highly consistent with the distribution of the simulated peristaltic wave load. In addition, we further evaluated the overall performance of the system, especially the sensing ability under different liquid filling conditions and the feasibility of the reconstruction calculation method, through a meticulous error analysis of the reconstruction results and the peristaltic wave input of the simulated swallowing esophagus.