Abstract

Background: In Barrett's patients, functional disorders of oesophageal motility are currently measured by oesophageal manometry. Yet abnormalities of oesophageal volume transport in the critical regions of the upper oesophageal sphincter (UOS) and lower oesophageal sphincter (LOS) cannot be determined using these methods.

Aims: To further characterise the activity of the sphincter regions, we developed a quantitative method for differentiation of oesophageal volume transport in Barrett's patients and healthy controls.

Methods: We used a new technique of processing scintigraphic images, with data analysis based on a new concept of relative local transit time. Twelve patients with Barrett's oesophagus and 11 healthy volunteers were examined using alimentary scintigraphy after a semisolid test meal in a multiple swallow test. In individual scintigraphic images of five swallows we studied: (1) overall oesophageal clearance and (2) the topographic profile of the relative local transit time obtained by image conversion to a two dimensional line graph. This profile was reconstructed by assembling constituent Gauss bands, allocating their integrals to five oesophageal regions according to their band position.

Results: (1) Overall oesophageal clearance was not significantly different between the two groups. (2) In comparison with healthy volunteers, relative regional transit times of all 12 Barrett's patients were significantly increased in the hypopharyngeal region and decreased in the region of the distal oesophagus. The extent of the decrease in the region of the distal oesophagus showed a close correlation with the length of Barrett's metaplasia.

Conclusion: Improvement in image processing allows alimentary scintigraphy to describe different regional patterns of oesophageal volume transport. Local oesophageal bolus transit is markedly abnormal in Barrett's patients without alteration in clearance. The presence of metaplasia itself implies a negative impact on both sphincter functions. These findings substantiate the diagnostic value of refined oesophageal scintigraphy.