Accuracy of an automatic impedance apparatus in a population with secretory otitis media: principles in the evaluation of tympanometrical findings

Area of Science:

• Otolaryngology
• Pediatric Audiology
• Medical Diagnostics

Background:

• Secretory otitis media (SOM) screening requires objective tests with high sensitivity and specificity.
• A portable automatic impedance apparatus was evaluated for its utility in SOM screening programs.

Purpose of the Study:

• To assess the sensitivity and specificity of a portable automatic impedance apparatus for diagnosing secretory otitis media (SOM).
• To determine the value of this device in meeting the demands of a screening program for SOM.

Main Methods:

• A double-blind, cross-sectional study involved 220 children with unilateral or bilateral SOM meeting surgical intervention criteria.
• All ears underwent tympanometry using the automatic impedance apparatus, followed by myringotomy.
• Otomicroscopy was used to confirm the presence of fluid behind the tympanic membrane.

Main Results:

• The apparatus demonstrated a sensitivity of 94.4% and a specificity of 52.9% for detecting SOM.
• Abnormal tympanometry results (B and C2 curves) were observed in ears with confirmed fluid.
• No correlation was found between tympanometry findings and middle ear fluid viscosity.

Conclusions:

• The automatic impedance apparatus is a simple, quick, and highly sensitive tool suitable for SOM screening.
• Due to its moderate specificity, results from the automatic impedance apparatus require confirmation with other diagnostic methods.