PIECEMEAL DEGLUTITION AND DYSPHAGIA LIMIT IN NORMAL SUBJECTS AND IN PATIENTS WITH SWALLOWING DISORDERS

Objective-Before the advanced evaluation of deglutition and selection of a treatment method, objective screening methods are necessary for p atients with dysphagia. In this study a new electroclinical test was e stablished to evaluate patients with dysphagia. Methods-This test is b ased on determining piecemeal deglutition; which is a physiological ph enomenon occurring when a bolus of a large volume is divided into two or more parts which are swallowed successively. The combined electroph ysiological and mechanical method used to record laryngeal movements d etected by a piezoelectric transducer, and activities of the related s ubmental integrated EMG (SM-EMG)-and sometimes the cricopharyngeal mus cle of the upper oesophageal sphincter (CP-EMG)-were performed during swallowing. Thirty normal subjects and 66 patients with overt dysphagi a of neurogenic origin were investigated after detailed clinical evalu ation. Twenty patients with a potential risk of dysphagia, but who wer e normal clinically at the time of investigation, were also evaluated to determine the specificity of the test. All subjects were instructed to swallow doses of water, gradually increasing in quantity from 1 ml to 20 ml, and any recurrence of the signals related to swallowing wit hin the eight seconds was accepted as a sign of dysphagia Limit. Resul ts-In normal subjects as well as in the patients without dysphagia, pi ecemeal deglutition was never seen with less than 20 mi water. This vo lume was therefore accepted as the lower limit of piecemeal deglutitio n. In patients with dysphagia, dysphagia limits were significantly low er than those of normal subjects. Conclusion-The method is a highly sp ecific and sensitive test for the objective evaluation of oropharyngea l dysphagia even in patients with suspected dysphagia of neurogenic or igin. It can also be safely and simply applied in any EMG laboratory.