Oral and pharyngeal transit of a paste bolus in Chagas' disease

We measured the oral and pharyngeal transit of a paste bolus in 20 patients with Chagas' disease and 21 controls. Each subject swallowed of a 10-ml paste bolus prepared with 50 ml of water and 4.5 g of instant food thickener labeled with 55.5 MBq of 99m technetium phytate. After the scintigraphic recording of the transit, we delineated regions of interest (ROI) corresponding to mouth, pharynx, and proximal esophagus. Time-activity curves were generated for each ROI. There was no difference between patients with Chagas' disease and controls with respect to the duration of oral and pharyngeal transit, amount of pharyngeal residue, or flux of bolus entry into the proximal esophagus. The amount of oral residue was higher in patients with Chagas' disease (median = 0.71 ml) than in controls (median = 0.45 ml). The pharyngeal clearance duration was longer in patients with Chagas' disease (median = 0.85 s) than in controls (median = 0.60 s). The oral transit duration of the patients with Chagas' disease and dysphagia (median = 0.55 s, n = 14) was shorter than the oral transit duration of chagasic patients without dysphagia (median = 0.80 s, n = 6). We conclude that when swallowing a paste bolus, patients with Chagas' disease may have an increased amount of oral residue and a longer pharyngeal clearance duration than asymptomatic volunteers.