title: A human model of restricted upper esophageal sphincter opening and its pharyngeal and UES deglutitive pressure phenomena.
abstract: Oropharyngeal dysphagia due to upper esophageal sphincter (UES) dysfunction is commonly encountered in the clinical setting. Selective experimental perturbation of various components of the deglutitive apparatus can provide an opportunity to improve our understanding of the swallowing physiology and pathophysiology. The aim is to characterize the pharyngeal and UES deglutitive pressure phenomena in an experimentally induced restriction of UES opening in humans. We studied 14 volunteers without any dysphagic symptoms (7 men, 66 ± 11 yr) but with various supraesophageal reflux symptoms. To induce UES restriction, we used a handmade device that with adjustment could selectively apply 0, 20, 30, or 40 mmHg pressure perpendicularly to the cricoid cartilage. Deglutitive pharyngeal and UES pressure phenomena were determined during dry and 5- and 10-ml water swallows × 3 for each of the UES perturbations. External cricoid pressure against the UES resulted in a significant increase in hypopharyngeal intrabolus pressure and UES nadir deglutitive relaxation pressure for all tested swallowed volumes (P < 0.05). Application of external cricoid pressure increased the length of the UES high pressure zone from 2.5 ± 0.2 to 3.1 ± 0.2, 3.5 ± 0.1, and 3.7 ± 0.1 cm for 20, 30, and 40 mmHg cricoid pressure, respectively (P < 0.05). External cricoid pressure had no significant effect on pharyngeal peristalsis. On the other hand, irrespective of external cricoid pressure deglutitive velopharyngeal contractile integral progressively increased with increased swallowed volumes (P < 0.05). In conclusion, acute experimental restriction of UES opening by external cricoid pressure manifests the pressure characteristics of increased resistance to UES transsphincteric flow observed clinically without affecting the pharyngeal peristaltic contractile function.
authors.affiliation: Peking University First Hospital, Beijing, China; and.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Jiao
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Ling
authors.initials: L
authors.lastname: Mei
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Tarun
authors.initials: T
authors.lastname: Sharma
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Mark
authors.initials: M
authors.lastname: Kern
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Patrick
authors.initials: P
authors.lastname: Sanvanson
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wisconsin rshaker@mcw.edu.
authors.forename: Reza
authors.initials: R
authors.lastname: Shaker
mesh_terms: D000368:Aged; D003413:Cricoid Cartilage / Q000503:physiopathology; D003679:Deglutition; D003680:Deglutition Disorders / Q000503:physiopathology*; D004867:Equipment Design; D049631:Esophageal Sphincter, Upper / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation; D008875:Middle Aged; D009119:Muscle Contraction; D010528:Peristalsis; D010609:Pharyngeal Muscles / Q000503:physiopathology; D010614:Pharynx / Q000503:physiopathology*; D011312:Pressure; D014160:Transducers, Pressure
keywords: UES; deglutition; manometry; pharynx; pressure