Question
Is it necessary to perform tympanometry on a patient if there are no middle ear concerns and the audiogram compares well with past audiograms?
Answer
Acoustic immittance measures are a routine component of the basic audiological evaluation. Tympanometry is one measure included in the acoustic immittance battery, along with static compliance and acoustic reflex testing. Results from these measures provide information regarding the mechanical transfer function of the outer and middle ear systems, and the neural integrity of the auditory nerve at the brainstem level. The question arises: Should these measures be repeated in subsequent evaluations if there are no middle ear concerns, and hearing sensitivity is unchanged?
When initially considered, repeating the acoustic immittance battery may not seem relevant. If hearing sensitivity has not changed, it can be assumed that middle ear status has not changed. However, it could be that middle ear status has changed. For example, a type B tympanogram could change to a type C tympanogram, or vice versa. Audiologically, this change may not cause a significant change in hearing, but the change in middle ear status would be diagnostically significant
More importantly, however, is the relevance of acoustic immittance in the basic audiometric test battery. If the goal of the basic audiological evaluation is to assess and monitor the status of the peripheral auditory system, acoustic immittance should always be included. The information it provides regarding outer ear and middle ear function cannot be obtained from pure tone results. Hearing sensitivity may not change, but the status of the auditory system cannot be determined unless all aspects of the system have been evaluated.
Wende Yellin started her career in the field of Communication Disorders as a teacher of the hearing impaired. She received her Bachelors degree from the University of Texas, but continued her education at the Univesity of Texas at Dallas, receiving both her Masters degree and Ph.D.. She has been an audiologist for over 25 years, working with both pediatric and adult populations, and is currently an Associate Professor in Communication Sciences and Disorders at Northern Arizona University in Flagstaff, Arizona. Her primary areas of focus are auditory processing/auditory processing disorders, and pediatric audiology.