Middle Ear Measurement in Infants and Children
Key Points
- Development of the external and middle ear over the first 6-8 months of life results in tympanometric data that may not reflect middle ear function when using a 226 Hz probe tone
- Evidence is mounting to suggest that 1000Hz tympanometry and wide-band assessment techniques may provide greater sensitivity to middle ear disorders in neonates and young infants
- Otoscopy should be conducted prior to the admittance evaluation to ensure that the test can be conducted safely, and to gather information for test interpretation
- If published normative data are used for middle ear assessment, ensure that measurements are obtained using the same test parameters as the published studies, or collect local norms
- The results of the middle ear test battery should be cross-checked with other behavioral and physiologic test results
- A quantitative description of the tympanogram is desirable in addition to a description of its shape.
- The measurement of infant acoustic stapedius reflexes should be conducted with a high-frequency probe tone. Power measures of middle ear function using a wide-band probe signal may also prove useful as this becomes available
Considerations When Testing Infants
- Low-frequency tympanometry measurements are generally considered alid and reliable predictors of middle ear function by about 7 months of age