A novel scalable electrode array and system for non‐invasively assessing gastric function using flexible electronics

• Published in: Neurogastroenterology and motility Vol. 35; no. 2; pp. e14418 - n/a
• Main Authors: Gharibans, Armen A., Hayes, Tommy C. L., Carson, Daniel A., Calder, Stefan, Varghese, Chris, Du, Peng, Yarmut, Yaara, Waite, Stephen, Keane, Celia, Woodhead, Jonathan S. T., Andrews, Christopher N., O'Grady, Greg
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.02.2023; John Wiley and Sons Inc
• Subjects: bioelectronics; Biomarkers; diagnostics; Electrodes; Electronics; Electrophysiology; Female; functional gastrointestinal disorders; gastric motility; Gastroenterology; Gastrointestinal Motility - physiology; Humans; Male; Mapping; Original; Reproducibility of Results; Silver chloride; Stomach - physiology; gastric motility; diagnostics; functional gastrointestinal disorders; bioelectronics
• ISSN: 1350-1925; 1365-2982; 1365-2982
• DOI: 10.1111/nmo.14418

Background Disorders of gastric function are highly prevalent, but diagnosis often remains symptom‐based and inconclusive. Body surface gastric mapping is an emerging diagnostic solution, but current approaches lack scalability and are cumbersome and clinically impractical. We present a novel scalable system for non‐invasively mapping gastric electrophysiology in high‐resolution (HR) at the body surface. Methods The system comprises a custom‐designed stretchable high‐resolution “peel‐and‐stick” sensor array (8 × 8 pre‐gelled Ag/AgCl electrodes at 2 cm spacing; area 225 cm2), wearable data logger with custom electronics incorporating bioamplifier chips, accelerometer and Bluetooth synchronized in real‐time to an App with cloud connectivity. Automated algorithms filter and extract HR biomarkers including propagation (phase) mapping. The system was tested in a cohort of 24 healthy subjects to define reliability and characterize features of normal gastric activity (30 m fasting, standardized meal, and 4 h postprandial). Key Results Gastric mapping was successfully achieved non‐invasively in all cases (16 male; 8 female; aged 20–73 years; BMI 24.2 ± 3.5). In all subjects, gastric electrophysiology and meal responses were successfully captured and quantified non‐invasively (mean frequency 2.9 ± 0.3 cycles per minute; peak amplitude at mean 60 m postprandially with return to baseline in <4 h). Spatiotemporal mapping showed regular and consistent wave activity of mean direction 182.7° ± 73 (74.7% antegrade, 7.8% retrograde, 17.5% indeterminate). Conclusions and Inferences BSGM is a new diagnostic tool for assessing gastric function that is scalable and ready for clinical applications, offering several biomarkers that are improved or new to gastroenterology practice. A novel scalable electrode array and system is presented that employs high‐resolution flexible electronics attached to a portable data logger, capable of non‐invasively mapping gastric motility accurately from the surface of the abdominal skin.