• diagnosis;
  • dysphagia;
  • esophagus;
  • impedance;
  • manometry;
  • pressure


Background and Aim

Patients with non-obstructive dysphagia (NOD) report symptoms of impaired esophageal bolus transit without evidence of bolus stasis. In such patients, manometric investigation may diagnose esophageal motility disorders; however, many have normal motor patterns. We hypothesized that patients with NOD would demonstrate evidence of high flow-resistance during bolus passage which in turn would relate to the reporting of bolus hold up perception.


Esophageal pressure-impedance recordings of 5 mL liquid and viscous swallows from 18 NOD patients (11 male; 19–71 years) and 17 control subjects (9 male; 25–60 years) were analyzed. The relationship between intrabolus pressure and bolus flow timing in the esophagus was assessed using the pressure flow index (PFI). Bolus perception was assessed swallow by swallow using standardized descriptors.


NOD patients were characterized by a higher PFI than controls. The PFI defined a pressure-flow abnormality in all patients who appeared normal based on the assessment esophageal motor patterns and bolus clearance. The PFI was higher for individual swallows during which subjects reported perception of bolus passage.


Bolus flow-resistance is higher in NOD patients compared with controls as well as higher in relation to perception of bolus transit, suggesting the presence of an esophageal motility disorder despite normal findings on conventional analysis.