Gastrointestinal System current projects

Ingested food is first processed in the mouth. The masticatory system is prone to dysfunction, whether with the teeth or with the jaw joints. Our research group conducts projects in modeling the jaw mechanics, including the application of a computational model of the human jaw to simulate eating movements, and to calculate the stresses and forces that are generated on the teeth.

Swallowing involves the transport of food via the pharynx and the oesophagus, beyond the gastro-oesophageal junction (GOJ) and into the stomach. Malfunction of the GOJ can lead to swallowing difficulties and contributes to gastro-oesophageal reflux disease. Our group is constructing a 3D computational model of the GOJ, which will be used to simulate the functional mechanical behaviour of the GOJ in normal and diseased states.

One way of improving our understanding of the physiology of the gastro-oesophageal junction is to obtain detailed anatomical information on its structure. Our group has created a 3D reconstruction of the microstructure of the human GOJ, which can be viewed using our interactive application.

The stomach is responsible for reducing the ingested food into a slurry. The food particles are broken down by powerful waves of contractions in the wall of the stomach, in combination with acid and enzymes. There is an underlying electrical activity that controls and coordinates this mechanical activity.

Gastric motility problems are common and not well understood. Our group develops detailed models of gastric electrical and mechanical activity that are used to help plan new diagnostic and treatment strategies for gastric diseases.

We are also undertaking the high-resolution electrical mapping of the gastro-intestinal (GI) tract during surgery, using novel electrodes designed by our group. Both normal and disease states are being examined. The results are being used to help guide our modelling program, and to inform the development of new diagnostic and treatment devices for GI disorders.

The small intestine serves primarily to absorb digested food, involving a sophisticated series of continuous movements and a number of chemical and cellular processes.

Intestinal ischaemia has a high mortality rate and is difficult to diagnose without the use of invasive procedures. Our group is developing a 3D computational model of the small intestine which offers the potential to non-invasively detect this problem.

The last important function of the gastro-intestinal tract is the elimination of waste. As many as 15% of New Zealanders suffer from faecal incontinence. Our group is working towards computational simulation on models customised to individual patients which can aid diagnosis and corrective surgery.