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Pyloric interventions are surgical procedures employed to increase the gastric emptying rate in gastroparesis patients. In this study, we use anin silicomodel to investigate the consequences of pyloric intervention on gastric flow and emptying for two phenotypes of gastroparesis: antral hypomotility and decreased gastric tone. The transpyloric pressure gradient predicted by thein silicomodel, based on viscous fluid flow equations, is compared againstin vivomeasurements. Both phenotypes exhibit a similar pre-procedural emptying rate reduction, but after pyloric surgery, antral hypomotility case with preserved gastric tone shows significant improvements in emptying rates, up to 131%, accompanied by bile reflux from the duodenum into the stomach. Conversely, severely reduced gastric tone cases exhibited a post-procedural reduction in the net emptying rate due to the relatively larger bile reflux. In cases with a combination of antral hypomotility and reduced gastric tone, post-procedural improvements were observed only when both conditions were mild. Our findings highlight the pivotal role of the relative increase in pyloric orifice diameter in determining post-operative emptying rates. The study suggests a possible explanation for the selective response of patients toward these procedures and underscores the potential ofin silicomodelling to generate valuable insights to inform gastric surgery.
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This content will become publicly available on April 1, 2026
Duodenogastric reflux in health and disease: insights from a computational fluid dynamics model of the stomach
An in silico model of the stomach is presented to study the phenomenon of duodenogastric reflux. We use the model to investigate the role of pyloric incompetence, food properties, and gastroparesis on reflux. This first-ever in silico study of duodenogastric reflux provides new insights into the mechanisms and factors implicated in this reflux and the sequelae of conditions that result from the exposure of the stomach lumen to bile.
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- Award ID(s):
- 2019405
- PAR ID:
- 10616123
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- American Journal of Physiology-Gastrointestinal and Liver Physiology
- Volume:
- 328
- Issue:
- 4
- ISSN:
- 0193-1857
- Page Range / eLocation ID:
- G411 to G425
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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