title: Variability of Eustachian tube function: comparison of ears with retraction disease and normal middle ears.
abstract: OBJECTIVE
  To explore the short-term and longterm variability of tubal opening and closing in ears with advanced retractions and in healthy ears.
  
  
  METHODS
  Twenty ears with retraction type middle ear disease (R-MED) and 20 normal ears underwent direct recording of the middle ear pressure during repeated forced openings, equalization of +100 daPa and -100 daPa by swallowing, Valsalva inflation, and forceful sniffing. Tests were performed twice (separated by 30 min) on each of 2 days separated by 3 to 4 months.
  
  
  RESULTS
  There was considerable intraindividual variability of the forced opening pressure and the closing pressure in both groups, within as well as between sessions and test days. Although the variability was 1.5 to 2 times higher in ears with retraction than in the normal group, mean Po and Pc did not differ between the groups. Compared with normal ears, ears with retraction changed more frequently from a positive to negative test response, or vice versa, when re-tested after 30 minutes. Rates of positive response in the equalization and Valsalva tests were significantly lower in diseased ears compared with normal ears.
  
  
  CONCLUSIONS
  Eustachian tube opening and closing functions vary more in ears with retraction disease than in normal ears, which is consistent with the variable clinical course of R-MED and implies that single tubal function tests have little prognostic value on the individual level.
authors.affiliation: Department of Otorhinolaryngology, Sunderby Hospital, Luleå, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Bunne
authors.forename: B
authors.initials: B
authors.lastname: Falk
authors.forename: B
authors.initials: B
authors.lastname: Magnuson
authors.forename: S
authors.initials: S
authors.lastname: Hellström
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004427:Ear Diseases / Q000503:physiopathology; D005064:Eustachian Tube / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis