title: Variability of Eustachian tube function in children with secretory otitis media. Evaluations at tube insertion and at follow-up.
abstract: OBJECTIVE
  Despite the variable clinical course of diseases related to Eustachian tube function, the variability of tubal function has been less focused than outcomes of single tests. This study aimed to compare the passive and active tubal function and its variability in children with secretory otitis media (SOM) at tube insertion and at follow-up.
  
  
  METHODS
  Thirty-eight ears in 19 children aged 4-10 years (mean 7.0 years) with long-standing SOM were examined 4-6 h after tube insertion, at 4 months and at 9 months. The pressure in the middle ear and the nasopharynx were recorded while performing (1) forced opening test, (2) equalization of +100 and -100 daPa, (3) Valsalva test, and (4) sniff test. The procedure was repeated after 30 min. Relationships were analyzed by uni- and multi-variate analysis of variance.
  
  
  RESULTS
  From tube insertion to 4 months, the mean forced opening pressure increased from 282+/-128 to 355+/-153 daPa (P<0.01), and the mean closing pressure from 91+/-51 to 126+/-82 daPa (P<0.01). There was no further change at 9 months. Female gender, serous effusion (in contrast to mucoid), and more than three previous episodes of acute otitis media were related to higher opening and closing pressures. At tube insertion, 60% and 16% equalized +100 and -100 daPa, respectively, and 28% succeeded in performing Valsalva inflation. The sniff test was positive in 32%, indicating a closing failure. These rates did not change significantly over time. For individual ears, outcomes of all tests varied considerably when retested after 30 min; P(o) changed by +/-12% and P(c) by +/-26%, and 9-29% of the ears changed from a positive to negative response, or vice versa, in the equalization, Valsalva, and sniff tests.
  
  
  CONCLUSIONS
  The unexpected finding of weaker closing forces at the day of tube insertion and increased tubal resistance at follow-up might be ascribed to changes in the muco-adhesive forces related to the disease and tube treatment. The pronounced intra-individual variability of test outcomes indicates that tubal function is dynamic and variable in ears prone to SOM, which emphasizes that results of single tubal function tests have very low prognostic value.
authors.affiliation: Department of Otorhinolaryngology, Sunderby Hospital, S-971 80, Luleå, Sweden. marie.bunne@nll.se
authors.forename: M
authors.initials: M
authors.lastname: Bunne
authors.forename: B
authors.initials: B
authors.lastname: Falk
authors.forename: S
authors.initials: S
authors.lastname: Hellström
authors.forename: B
authors.initials: B
authors.lastname: Magnuson
mesh_terms: D000704:Analysis of Variance; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D005064:Eustachian Tube / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008876:Middle Ear Ventilation / Q000009:adverse effects / Q000379:methods*; D015999:Multivariate Analysis; D010034:Otitis Media with Effusion / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D011312:Pressure; D011336:Probability; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome