PhD Thesis

Oesophageal motility: A study of the transport mechanism of the

oesophagus using fluoromanometry, nonlinear analysis and

oesophageal modelling


PhD Thesis
MSc Thesis


This is in a chapter format with each being mostly readable in its own right

Chapter 1 Introduction

This highlights both the importance of trying to find suitable features to use in measuring oesophageal motility and the difficulties that have been found using current modalities. This chapter includes an overview of the structure of the thesis.

Chapter 2 Fluoromanometry

This describes the fluoromanometry system developed and the improvements that have been carried out since the first phase of development described in the MSc thesis.

Chapter 3 Fluoromanometry patient study

This is a large chapter that describes a study of 25 patients. It details the methods of analysis used. It compares the results with previous studies. I feel there are some important results from this study that any one interested in the study of oesophageal manometry should examine carefully.

Included in the discussion is a close look at the parameters required to measure oesophageal function and an examination of the current measurement of pH, both of which I believe have many problems associated with them. To some extent the results and analysis may explain why many papers have conflicting rests.

I look forward to any comments on this work.

Chapter 4 Complexity in the oesophagus

This chapter examines a measure of complexity of the oesophagus between individuals in an asymptomatic study group. It highlights that the swallowing system is widely different between individuals. This again is important as it explains why current features measured such as peak height etc may not be suitable measurements of a highly adaptive non linear system.

Chapter 5 Modelling oesophageal function

This examines methods which have been used to model the mechanisms of the oesophagus and presents a new method using cellular automata to model the excitation mechanism at the macroscopic scale. In practice this is the scale at which I believe we can model oesophageal excitation  as a result of the number of neurones and complexity of innervation. However this model does reveal many of the observed properties and predicts mechanism of failure that are observed and suggest the necessity for higher level innervation. As with any model this may be useful or just reflect  the properties of the tools used to build the model. 

Chapter 6 Preliminary and future work

This examines various elements of new techniques which may be useful in future studies. Clearly the dimension of  the oesophageal system is very high. However, modern tools of complexity analysis and classification using neural networks of either the raw data or selected features may have considerable amount to offer GI Measurement. These techniques are now widely being used in many other areas of medical engineering.

This chapter concludes with an endnote which examines and highlights the need for further collaboration between those field of medical engineering and clinical specialities relating to GI physiology.

It is of note that that from my perspective the world of GI measurement is ‘fuzzy’. There are many physical unknowns and both the investigations experiments are highly complex giving high dimensional results. However, this makes the field extremely challenging to the researcher.




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