Modeling of the mechanical function of the human gastroesophageal junction using an anatomically realistic three-dimensional model

Auckland Bioengineering Institute, The University of Auckland, New Zealand.
Journal of Biomechanics (Impact Factor: 2.75). 06/2009; 42(11):1604-9. DOI: 10.1016/j.jbiomech.2009.04.041
Source: PubMed


The aim of this study was to combine the anatomy and physiology of the human gastroesophageal junction (the junction between the esophagus and the stomach) into a unified computer model. A three-dimensional (3D) computer model of the gastroesophageal junction was created using cross-sectional images from a human cadaver. The governing equations of finite deformation elasticity were incorporated into the 3D model. The model was used to predict the intraluminal pressure values (pressure inside the junction) due to the muscle contraction of the gastroesophageal junction and the effects of the surrounding structures. The intraluminal pressure results obtained from the 3D model were consistent with experimental values available in the literature. The model was also used to examine the independent roles of each muscle layer (circular and longitudinal) of the gastroesophageal junction by contracting them separately. Results showed that the intraluminal pressure values predicted by the model were primarily due to the contraction of the circular muscle layer. If the circular muscle layer was quiescent, the contraction of the longitudinal muscle layer resulted in an expansion of the junction. In conclusion, the model provided reliable predictions of the intraluminal pressure values during the contraction of a normal gastroesophageal junction. The model also provided a framework to examine the role of each muscle layer during the contraction of the gastroesophageal junction.

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Available from: Vijay Rajagopal
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    • "This will allow the integration of anatomy and physiology into a single model illustrating their co-dependence. A preliminary anatomically realistic three-dimensional computer model has been constructed to study the relationship between the anatomy and physiology of the GOJ (Yassi et al., 2009). In addition to modeling normal physiological events (including oesophageal peristalsis, swallowing induced relaxation of the lower oesophageal sphincter, and transient lower oesophageal sphincter relaxation in response to distension of the stomach cardia), it is also possible to model abnormal physiology. "
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