title: Rapid air infusion into the oesophagus: Motor response in patients with achalasia and nonobstructive dysphagia assessed with high-resolution manometry.
abstract: BACKGROUND
  Achalasia is a neurodegenerative disorder of the oesophagus. Alteration of motor activity induced by oesophageal distension has not been explored.
  
  
  OBJECTIVE
  To investigate this function, using high-resolution Manometry.
  
  
  METHODS
  This study enrolled 15 healthy subjects, 15 nonobstructive dysphagia (NOD), and 18 achalasia patients successfully treated with pneumatic dilation (six with restored peristalsis). The three groups underwent five rapid (<1 s) intraoesophageal infusions of 20-ml air boluses, followed by eight 5-ml water swallows.
  
  
  RESULTS
  WHEREAS THE RESPONSE RATE TO WATER SWALLOWS WAS SIMILAR IN THE THREE GROUPS, AIR INFUSION INDUCED A LOWER RESPONSE RATE IN ACHALASIA (MEDIAN, INTERQUARTILE RANGE: 70%, 40-100%) and, to a lesser extent, in NOD patients (100%, 60-100%) than in healthy subjects (100%, 100-100%; p < 0.001 and p = 0.06, respectively). However, the response rate was highly variable in achalasia patients irrespective of presence of peristalsis. Furthermore, the strength of motor response to air infusion when compared to water swallows was diminished in achalasia patients but not in healthy subjects and NOD.
  
  
  CONCLUSIONS
  Motor response to rapid air infusion was variably impaired in achalasia. The role of this alteration in the long-term outcome deserves evaluation.
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Elvevi
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Mauro
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Consonni
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Delia
authors.initials: D
authors.lastname: Pugliese
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Tenca
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Franchina
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Conte
authors.affiliation: Università degli Studi of Milan, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Penagini
keywords: Achalasia; dysphagia; high-resolution manometry; oesophageal distension; oesophageal motility