Advances in the manometric and radiographic assessment of oesophageal motility disorders

Abstract

Background and aims High-resolution manometry is the reference standard test for the diagnosis of oesophageal motility disorders. Yet diagnosis is imperfect, with both suboptimal sensitivity and specificity in some settings. One reason may be the standard manometric protocol whereby motility is assessed using small volume water swallows whilst supine, which is inherently not reflective of normal swallowing behaviour. This thesis examines the utility of assessing oesophageal function in a more realistic fashion while ingesting larger volumes of liquid and solids; hypothesising that this would lead to more clinically meaningful results. I aimed to evaluate the utility of such “provocative testing” during manometry in differentiating gastro-oesophageal reflux disease phenotypes, improving the diagnostic yield for achalasia and determining the functional relevance of manometric oesophagogastric junction outflow obstruction. The barium swallow, and in particular the timed barium swallow, is a useful complementary investigation that provides valuable information regarding bolus flow as well as oesophageal contractility during ingestion of larger volumes of liquid. This thesis also aimed to compare its diagnostic yield over the standard manometric protocol in achalasia, and to examine whether novel metrics of emptying on timed barium swallow would improve its correlation with symptoms.

Key findings In Barrett’s oesophagus, motility was poor when challenged with the more representative workload of provocative testing, a finding not seen in other GORD phenotypes. Second, use of provocative testing with timed barium swallow increases the diagnostic yield for achalasia compared to manometry with small volume water swallows alone. Such extra cases respond favourably to sphincter-disrupting therapy. Third, measurement of the percentage reduction in oesophageal stasis on timed barium swallow following therapy correlates closely with symptomatic response, unlike other metrics of oesophageal emptying. Fourth, manometric findings from provocative testing can be used to differentiate clinically relevant from spurious cases of oesophagogastric junction outflow obstruction with a high degree of accuracy, whereas findings from small volume water swallows and barium oesophagography do not.