To evaluate dysphagia and manometric changes in the upper oesophageal sphincter in patients with unilateral vocal fold paralysis.

Thirty patients with unilateral vocal fold paralysis due to vagal nerve paralysis scheduled for evaluation were enrolled in the study group; 24 healthy subjects were included in the control group. Upper oesophageal sphincter basal and residual pressure, relaxation time, and pharyngeal pressure values were evaluated by manometry. All patients completed the Turkish Eating Assessment Tool 10 questionnaire, the MD Anderson dysphagia questionnaire and the reflux symptom index form.

Swallowing assessment questionnaires and reflux symptom index results were significantly higher in the study group. Upper oesophageal sphincter basal and relaxation pressures were lower in the study group. Upper oesophageal sphincter relaxation time was shorter in the study group, but pressure values recorded from the pharynx were higher.

Upper oesophageal sphincter manometric pressure was lower in patients with unilateral vocal fold paralysis. A hypotonic sphincter likely contributes to dysphagia and aspiration.

To discover the anatomist who first identified the upper oesophageal sphincter.

The authors searched dozens of antique anatomy textbooks kept in the old section of the ‘Vincenzo Pinali’ Medical Library of Padua University, looking for descriptions of the upper oesophageal sphincter.

The oesophageal sphincter was drawn correctly only in 1601, by Julius Casserius, in the book De vocis auditusque organis historia anatomica… (which translates as ‘An Anatomical History on the Organs of Voice and Hearing …’), and was properly described by Antonio Maria Valsalva in 1704 in the book De aure humana tractatus… (‘Treatise on the Human Ear …’).

Anatomists Casserius and Valsalva can be considered the discoverers of the ‘oesophageal sphincter’.