Effects of Anatomical Variations of the Stomach on Body-Surface Gastric Mapping Investigated Using a Large...

Area of Science:

• Biomedical Engineering
• Computational Physiology
• Gastroenterology

Background:

• Body-surface gastric mapping (BSGM) uses cutaneous electrodes to measure gastric slow wave potentials.
• Current BSGM protocols lack standardization for electrode placement and do not account for anatomical variations.

Purpose of the Study:

• To quantify the impact of stomach anatomical variation on body surface potentials measured by BSGM.
• To develop a foundation for standardized BSGM electrode array design and placement protocols.

Main Methods:

• Developed 93 subject-specific stomach and torso models using finite element meshes from Cancer Imaging Archive data.
• Simulated gastric slow waves (antegrade and colliding waves) using a bidomain model.
• Employed forward modeling to simulate body-surface potentials and analyzed signals from a 5x5 electrode array.

Main Results:

• Quantified anatomical parameters like distance from xiphoid process (8.6 ± 2.2 cm) and orientation (195 ± 20.0°).
• Demonstrated that signal amplitude (∆ϕ) and orientation (θ) metrics effectively differentiate antegrade and colliding wave simulations.
• Correlated electrophysiological simulations of wave propagation with BSGM signal metrics.

Conclusions:

• Anatomical variations significantly influence BSGM signal interpretation.
• Signal amplitude and orientation are key metrics for distinguishing different gastric wave patterns.
• This research provides crucial data for improving clinical BSGM electrode array design and placement.