In this thesis, the relationships among oesophageal motility, bolus clearance and sensory perception of oesophageal stimuli in patients with several dysphagia syndromes were investigated. The work is divided into the following major sections: 1) Current advances in the application of impedance and its utility in distinguishing clearance characteristics between primary and secondary peristalsis; 2) The advances in our understanding of peristaltic motor characteristics, oesophageal bolus clearance and symptom perception in dysphagia syndromes; 3) Peristaltic dysfunction, impaired bolus clearance and symptom perception in gastro-oesophageal reflux disease (GORD) and in patients with globus; 4) TRPV1 expression in oesophageal mucosa in patients with GORD. The main findings from this work are: 1) Secondary peristalsis is less effective as primary peristalsis regarding esophageal transit and clearance of a liquid bolus. 2) In patients with non-obstructive dysphagia (NOD), bolus clearance by both morphologically normal and aberrant secondary peristaltic sequences is impaired. 3) Although, when compared with healthy controls, patients with NOD have a higher prevalence of non-specifically abnormal motor patterns, there is a poor correlation between dysphagia and oesophageal dysmotility. 4) Whereas manometry identified motility abnormalities in one quarter of patients with GORD, impedance demonstrated that the majority of these patients, as well as some patients with normal manometry, had defective bolus clearance. 5) Although patients with erosive GORD have delayed oesophageal bolus clearance, manometric characteristics in these patients are comparable to those seen in non-erosive reflux disease (NERD). These findings are compatible with the hypothesis that abnormal oesophageal bolus clearance may reflect a continuum of dysfunction secondary to increasing oesophageal mucosal damage. 6) Patients with globus are characterized by oesophageal visceral hypersensitivity and aberrant viscerosomatic referral of mechanical and electrical stimuli to the oesophagus. These findings support the hypothesis that oesophageal hypersensitivity with associated viscerosomatic referral patterns are an important pathogenetic mechanism for globus. 7) Patients with erosive GORD exhibit greater gene expression of TRPV1 in oesophageal mucosa when compared with NERD or healthy controls. These findings support the hypothesis that chronic inflammation may lead to the release of mediators which may modulate function of primary sensory neurons.

In this thesis, the relationships among oesophageal motility, bolus clearance and sensory perception of oesophageal stimuli in patients with several dysphagia syndromes were investigated. The work is divided into the following major sections: 1) Current advances in the application of impedance and its utility in distinguishing clearance characteristics between primary and secondary peristalsis; 2) The advances in our understanding of peristaltic motor characteristics, oesophageal bolus clearance and symptom perception in dysphagia syndromes; 3) Peristaltic dysfunction, impaired bolus clearance and symptom perception in gastro-oesophageal reflux disease (GORD) and in patients with globus; 4) TRPV1 expression in oesophageal mucosa in patients with GORD. The main findings from this work are: 1) Secondary peristalsis is less effective as primary peristalsis regarding esophageal transit and clearance of a liquid bolus. 2) In patients with non-obstructive dysphagia (NOD), bolus clearance by both morphologically normal and aberrant secondary peristaltic sequences is impaired. 3) Although, when compared with healthy controls, patients with NOD have a higher prevalence of non-specifically abnormal motor patterns, there is a poor correlation between dysphagia and oesophageal dysmotility. 4) Whereas manometry identified motility abnormalities in one quarter of patients with GORD, impedance demonstrated that the majority of these patients, as well as some patients with normal manometry, had defective bolus clearance. 5) Although patients with erosive GORD have delayed oesophageal bolus clearance, manometric characteristics in these patients are comparable to those seen in non-erosive reflux disease (NERD). These findings are compatible with the hypothesis that abnormal oesophageal bolus clearance may reflect a continuum of dysfunction secondary to increasing oesophageal mucosal damage. 6) Patients with globus are characterized by oesophageal visceral hypersensitivity and aberrant viscerosomatic referral of mechanical and electrical stimuli to the oesophagus. These findings support the hypothesis that oesophageal hypersensitivity with associated viscerosomatic referral patterns are an important pathogenetic mechanism for globus. 7) Patients with erosive GORD exhibit greater gene expression of TRPV1 in oesophageal mucosa when compared with NERD or healthy controls. These findings support the hypothesis that chronic inflammation may lead to the release of mediators which may modulate function of primary sensory neurons.