title: Pharyngeal dilation in cricopharyngeus muscle dysfunction and Zenker diverticulum.
abstract: OBJECTIVE
  Prolonged obstruction at the level of the lower esophageal sphincter is associated with a dilated, poorly contractile esophagus. The association between prolonged obstruction at the level of the upper esophageal sphincter (UES) and dilation and diminished contractility of the pharynx is uncertain. The purpose of this investigation was to evaluate the association between prolonged obstruction at the level of the UES and dilation and diminished contractility of the pharynx.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  The fluoroscopic swallow studies of all persons with cricopharyngeus muscle dysfunction (CPD) diagnosed between January 1, 2006 and December 31, 2008 were retrospectively reviewed from a clinical database. Three categories of CPD were defined: nonobstructing cricopharyngeal bars (CPBs), obstructing CPBs, and Zenker diverticulum (ZD). The primary outcome measure was the pharyngeal constriction ratio (PCR), a surrogate measure of pharyngeal strength on fluoroscopy. Secondary outcome measures included pharyngeal area in the lateral fluoroscopic view and UES opening. The outcome measures were compared between groups and to a cohort of nondysphagic age- and gender-matched controls with the analysis of variance.
  
  
  RESULTS
  A total of 100 fluoroscopic swallow studies were evaluated. The mean age (+ or -standard deviation) of the cohort was 70 years (+ or -10 years). Thirty-six percent were female. The mean PCR progressively increased, indicating diminishing pharyngeal strength, from the normal (0.08), to the nonobstructing CPB (0.13), to the obstructing CPB (0.22), to the ZD group (0.28) (P < .001 with trend for linearity). There was a linear increase in pharyngeal area from the normal (8.75 cm(2)) to the nonobstructing CPB (10.00 cm(2)), to the obstructing CPB (10.46 cm(2)), to the ZD group (11.82 cm(2)) (P < .01 with trend for linearity).
  
  
  CONCLUSIONS
  The data suggest that there is an association between cricopharyngeus muscle dysfunction and progressive dilation and weakness of the pharynx. Laryngoscope, 2010.
authors.affiliation: Center for Voice and Swallowing, University of California, Davis School of Medicine, Department of Otolaryngology/HNS, Sacramento, California, USA. peter.belafksy@ucdmc.ucdavis.edu
authors.forename: Peter C
authors.initials: PC
authors.lastname: Belafsky
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Rees
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Allen
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Leonard
mesh_terms: D000368:Aged; D001466:Barium Sulfate; D015331:Cohort Studies; D003287:Contrast Media / Q000008:administration & dosage; D003680:Deglutition Disorders / Q000503:physiopathology / Q000628:therapy*; D004106:Dilatation / Q000379:methods*; D004108:Dilatation, Pathologic / Q000503:physiopathology / Q000628:therapy; D049631:Esophageal Sphincter, Upper / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004940:Esophageal Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010608:Pharyngeal Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D010609:Pharyngeal Muscles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012189:Retrospective Studies; D016672:Zenker Diverticulum / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*
chemical_list: D003287:Contrast Media; D001466:Barium Sulfate