title: Seasonal differences of tympanogram and middle ear findings in children.
abstract: BACKGROUND
  It is a known fact that bacterial or viral acute otitis media occurs more frequently in the winter months. Only a few older studies on seasonal differences in middle ear findings are available. These studies are based solely on tympanography, without correlation to intraoperative middle ear findings. This study addresses the question of whether seasonal differences can be found in the preoperative tympanogram and in the corresponding intraoperative findings in children with chronic middle ear problems.
  
  
  METHODS
  This retrospective study included patients who had undergone myringotomy with or without tympanostomy tube insertion at the Charité-Universitätsmedizin Berlin between January and December 2011. Corresponding to the catarrhal phases, winter months were defined as those from November to April; summer months from May to October. The preoperative tympanogram and the documented intraoperative middle ear finding were statistically analyzed for seasonal differences.
  
  
  RESULTS
  A total of 654 ears from 206 male and 127 female patients with mean age 3.7 ± 2.5 years were analyzed. In the majority of cases, a type B tympanogram was found (n = 376; 57.5%), whereas the middle ear was filled with air in 19.1% of cases. No significant seasonal differences were found for either the intraoperative middle ear findings or the preoperative tympanograms (p > 0.05).
  
  
  CONCLUSIONS
  For children with a typical history of chronic otitis media without effusion and chronic tube ventilation dysfunction, myringotomy with or without tympanostomy tube insertion is indicated independently of the season. The results indicate that a wait-and-see approach with hope of improvement during the summer months is not rational.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Charité - Universitätsmedizin Berlin Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany. steffen.knopke@charite.de.
authors.forename: S
authors.initials: S
authors.lastname: Knopke
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Charité - Universitätsmedizin Berlin Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Böttcher
authors.affiliation: Craniofacial Unit, Chelsea and Westminster Hospital, London, UK.
authors.forename: P
authors.initials: P
authors.lastname: Chadha
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Charité - Universitätsmedizin Berlin Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Olze
authors.affiliation: Department of Otorhinolaryngology, AMEOS Klinikum Haldensleben, Haldensleben, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Bast
mesh_terms: D000158:Acoustic Impedance Tests / Q000379:methods / Q000706:statistics & numerical data*; D000293:Adolescent; D017677:Age Distribution; D001299:Audiometry / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010033:Otitis Media / Q000175:diagnosis* / Q000453:epidemiology* / Q000503:physiopathology; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D012621:Seasons; D012680:Sensitivity and Specificity; D017678:Sex Distribution
keywords: Eustachian tube; Middle ear effusion; Otitis media; Paracentesis; Tympanic membrane