title: Equivalent volume: study in subjects with chronic otitis media.
abstract: The equivalent ear canal volume ranges from 0.3 ml to 1.0 ml in children and from 0.65 to 1.75 ml in adults. In subjects with chronic otitis media these values can be different, according to the disease status.
  
  
  OBJECTIVE
  To study the equivalent ear canal volume in 52 ears of patients with chronic otitis media with and without active infection.
  
  
  METHODS
  Clinical prospective with transversal cohort.
  
  
  METHODS
  The equivalent ear canal volume was obtained from 52 ears diagnosed with chronic otitis media with and without active infection and in age and gender matched control group. The study group with active infection was evaluated before and after clinical treatment.
  
  
  RESULTS
  Equivalent ear canal volume mean for the studied groups with and without infection and for the control group was 2.86 ml; 1.42 ml and 0.80 ml, respectively. The equivalent ear canal volume mean for the study group with infection prior and post clinical treatment was 1.42 ml and 1.82 ml, respectively.
  
  
  CONCLUSIONS
  The equivalent ear canal volume mean was higher in patients with chronic otitis media. We did not observe variation of equivalent ear canal volume before and after clinical treatment.
authors.affiliation: Federal University of Sao Paulo, Escola Paulista de Medicina. anapalencar@yahoo.com.br
authors.forename: Ana P T
authors.initials: AP
authors.lastname: Alencar
authors.forename: Maria C M
authors.initials: MC
authors.lastname: Iório
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Morales
mesh_terms: D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002648:Child; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D004432:Ear, Middle / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010034:Otitis Media with Effusion / Q000473:pathology* / Q000628:therapy; D011446:Prospective Studies; D018709:Statistics, Nonparametric