Background: The pathology of oesophageal motility disorders is poorly understood. Oesophageal manometry provides only a descriptive assessment of luminal pressure changes. This study applied the investigative methods of the neurophysiologist to gain insight into the pathophysiology of these disorders.
Methods: Twelve healthy volunteers and 28 patients with oesophageal motility disorders underwent oesophageal manometry and balloon stimulation studies. Cortical evoked potentials (CEPs) in response to electrical stimulation of the oesophagus and oesophageal motor evoked potentials (MEPs) to transcranial magnetic stimulation of the cerebral cortex were recorded.
Results: Only two patients had abnormalities with a primary defect in muscle function. Fifteen had abnormal responses to balloon stimulation with normal CEPs and MEPs, suggesting a defect in the intrinsic nerves of the oesophagus. Five with achalasia did not respond to balloon stimulation and had abnormal CEPs and MEPs, suggesting widespread neural defects. The remainder had a variety of abnormal responses suggesting possible defects in receptor sensitivity, central processing or sensory neuropathy. There was no correlation between the manometric diagnosis and abnormal neurophysiology, except in patients with achalasia.
Conclusion: Neurophysiological testing suggests that oesophageal motility disorders are most commonly due to a variety of neural defects.