Toward a Wireless Electronic Capsule With Microsensors for Detecting Dysfunction of Human Gastric Motility

This paper presents a method for detecting human gastric-motility dysfunction using a wireless electronic capsule. The capsule's main components include an application-specific integrated circuit, three sensors (temperature, pH, and pressure), an RF transceiver, and batteries. In addition, a portable data recorder was developed to receive and store the data transmitted by the wireless capsule. In particular, experimental results indicated that the maximum error and measuring range of the pressure sensor were 0.15 and 90-120 kPa, respectively. Using pressure data from the human stomach, a joint algorithm based on phase space reconstruction and independent component analysis was applied in the analysis of gastric motility. Implementation results showed that this joint algorithm could effectively obtain the components of pressure data for the human stomach that were caused by breathing, movement, contractions of abdominal muscles, and electrogastrogram. In 24 human experiments, poor gastric motility (functional dyspepsia and delayed gastric emptying) was identified with a recognition rate of nearly 80%. In particular, interdigestive motor complex and digestive motor complex related to human gastric motility were also identified.