Multiscale and multiphysics numerical analysis of enteric nervous signal sensing in wireless capsule endoscopy applications

Objectives: Wireless Capsule Endoscopy (WCE) is a revolutionary technique for exploring gastrointestinal (GI) tract using aningestible capsule, that offers valuable insights into poorly understood pathologies, such as functional gastric disorders. Recentstudies have highlighted the rapid connections between specific enteroendocrine cell, known as Neuropods, and central nervoussystem via vagal synapses, which may play a role in functional gastric disorders. This paper presents a numerical study to verify the feasibility of performing neuronal sensing through WCE, focusing on the minimum enteric neural signal detectable by integrated electrodes. Technology or Method: Multiscale intestinal cavity models were developed in Comsol Multiphysics (v. 6.2), incorporating two capsule configurations, conformal ring electrodes, and reconstructed Neuropod action potentials derived from electrophysiological data. The electric signals were coupled with a readout circuit to model the acquisition of extracellular potentials. Results: The minimum detected signalis in the mV range, consistent with the sensitivity achievable by miniaturized electrode technologies suitable for ingestible devices. Multiscale validation showed strong agreement between millimetricand full-scale models in both waveform and amplitude. Conclusions: This study confirms the feasibility of enteric neuronal sensing using an ingestible capsule equipped with conformal electrodes. Clinical or Biological Impact: Using this technology for enteric neural sensing could advance our understanding of functional gastric disorders, the gut-brain axis communication and related cognitive functions.