A study of tympanometric types and risk factors of abnormal tympanogram in preschool children in Bangkok by using portable tympanometer screening

Abstract

A tympanometer is a screening device for detecting middle-ear disorders in young children. Middle ear pathology with associated hearing loss may result in significant auditory, linguistic, educational, and psychosocial complications for affected children. This research aimed to study tympanometric types in preschool children. Interviews and questionnaires were administered to explore for the possible predisposing factors for abnormal tympanograms. Four hundred and twenty-one children aged between 2 to 7 years-old who were enrolled in school in Bangkok were screened using the portable tympanometry setting probe tone frequency of 226 Hz and 1000 Hz. A high- frequency probe tone at 1000 Hz was played for the children who showed type A tympanogram at 226 Hz in order to investigate for multipeaked tympanograms. The results showed abnormal low-frequency tympanograms in 35.6% of children, which was unilateral in 22.8% and bilateral in 12.8% of them. The percentage of abnormal tympanograms ranking from highest to lowest were type B (14.5%), type C (12.4%), type Ad (4.6%) and type As (4.3%). When a high frequency probe tone at 1000 Hz was administered to the ear which showed a type A tympanogram, the results showed the percentage of multipeaked tympanograms ranking from highest to lowest were 3B1G (46.0%), 1B1G (40.3%), 3B3G (7.4%), 5B3G (3.0%), and other types of multipeaked tympanograms were 3.3%. The Odds ratio of unilateral abnormal tympanogram was 2.07, meaning that the children who had a unilateral abnormal tympanogram in one ear were almost 2 times more likely to have other types of multipeaked tympanograms in the other ear than the children who did not have a unilateral abnormal tympanogram in one ear. There were significant relationships between gender, family's history of Otitis Media with effusion (OME), previous history of asthma and abnormal tympanograms (P< 0.05), in which the subject was male, the subject's family had history of OME, and the subject had a previous history of asthma thus increasing the risk of having abnormal tympanograms. This study recommended that this screening protocol should be used as a guideline in using a portable tympanometry to detect early middle ear disorders for proper hearing management. The children who had unilateral abnormal tympanograms should be measured by multiple frequency tympanometry in order to determine middle ear functionality. These middle ear screening protocols should be conducted in provincial areas for the purpose of data comparison