title: High-resolution impedance manometry measurement of bolus flow time in achalasia and its correlation with dysphagia.
abstract: BACKGROUND
  We assessed whether a high-resolution impedance manometry (HRIM) metric, bolus flow time (BFT) across the esophagogastric junction (EGJ), was abnormal in achalasia patients subtyped by the Chicago Classification and compared BFT to other HRM metrics.
  
  
  METHODS
  HRIM studies were performed in 60 achalasia patients (14 type I, 36 type II and 10 type III) and 15 healthy controls. Studies were analyzed with a MATLAB program to calculate BFT using a virtual HRIM sleeve. Integrated relaxation pressure (IRP) and basal end-expiratory EGJ pressure were also calculated. The relationship between BFT and dysphagia symptom scores was assessed using the impaction dysphagia questionnaire (IDQ).
  
  
  RESULTS
  Median BFT was significantly lower in achalasia patients (0.5 s, range 0.0-3.5 s) compared to controls (3.5 s, range 2.0-5.0 s; p < 0.05). BFT was significantly lower in types I and II than in type III achalasia in both the supine and upright positions (p < 0.0001). BFT was the only HRIM metric significantly associated with IDQ score in both the supine (R(2)  = 0.20, p = 0.0046) and upright positions (R(2)  = 0.27, p = 0.0002).
  
  
  CONCLUSIONS
  BFT was significantly reduced in all subtypes of achalasia and complementary to the IRP as a diagnostic discriminant in equivocal achalasia cases. Additionally, BFT had a more robust correlation with dysphagia severity compared to other metrics of EGJ function.
authors.affiliation: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Carlson
authors.affiliation: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: K
authors.initials: K
authors.lastname: Dykstra
authors.affiliation: Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: J
authors.initials: J
authors.lastname: Sternbach
authors.affiliation: Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: E
authors.initials: E
authors.lastname: Hungness
authors.affiliation: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Kahrilas
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Ciolino
authors.affiliation: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Pandolfino
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003680:Deglutition Disorders / Q000150:complications / Q000503:physiopathology*; D017097:Electric Impedance; D004931:Esophageal Achalasia / Q000150:complications / Q000503:physiopathology*; D004943:Esophagogastric Junction / Q000503:physiopathology*; D005260:Female; D005772:Gastrointestinal Transit; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D012720:Severity of Illness Index; D055815:Young Adult
keywords: achalasia; dysphagia; esophagus; impedance; manometry