A scintigraphic study of oropharyngeal swallowing dynamics in Chagas' disease

We studied oropharyngeal function in patients with Chagas' disease and oeso phageal disease. Twenty-four patients with Chagas' disease, 17 of them with oesophageal disease, were submitted to scintigraphic oropharyngeal transit . A single swallow of a 10-mL bolus of water labelled with 40 MBq Tc-99m-ph ytate, followed by image acquisition at 20 images s(-1) yielded time-activi ty curves in which oropharyngeal dynamics was evaluated. Thirteen normal vo lunteers were used as controls. Oral transit was longer for chagasics with oesophageal disease than for controls (P=0.004) or for chagasics with a nor mal oesophagus (P=0.028). Oesophageal filling rate, measured by the slope o f the ascending aspect of the oesophageal radioactivity curve, was lower fo r chagasics with oesophageal disease than for controls (P=0.037). Also, max imum oesophageal filling rate was lower (P=0.021) and occurred later (P=0.0 03) for chagasics with oesophageal disease than for controls. Pharyngeal cl earance was positively correlated with oral transit (r=0.603, P=0.002). We conclude that chagasic oesophageal disease is associated with oral transit delay and a slower oesophageal filling rate.