Automated Adaptive Wideband Acoustic Stapedius Reflex Thresholds in Adults With Normal Hearing and Sensorineural...

This study compared the measurement of the acoustic stapedius reflex threshold (ART) obtained using a traditional method with that obtained using an automated adaptive wideband (AAW) method. Participants included three groups of adults with normal hearing (NH), mild sensorineural hearing loss (SNHL), or moderate SNHL. The purpose of the study was to compare ARTs for the three groups and to determine which method had the best performance in detecting SNHL.

Ipsilateral and contralateral ARTs were obtained using 0.5, 1, and 2 kHz tonal activators, and broadband noise (BBN) activators on a traditional admittance system (Clinical) at tympanometric peak pressures (TPP) and on an experimental wideband system using an AAW method at both ambient pressure and TPP. ART data previously reported for 39 NH adults with a mean age of 47.7 years were compared with data for 25 participants with mild SNHL with a mean age of 63.8 years, and 20 participants with moderate SNHL with a mean age of 65.7 years. Differences in ARTs between the normal-hearing and SNHL groups for the three methods were examined using a General Linear Model Repeated-Measures test. A receiver operating characteristic curve (ROC) analysis was also used to determine the ability of an ART test to detect SNHL.

For the 0.5 kHz activator condition, there were no significant group mean differences in ART between NH and SNHL groups for either ipsilateral or contralateral activator presentation modes for the Clinical or AAW methods. There were significant group mean differences for the 1 and 2 kHz tonal activators and BBN activator for both ipsilateral and contralateral modes with greater differences in ART between groups for the AAW method than the Clinical method. In these conditions, the mean ART was lower for the AAW tests relative to the Clinical test. The greatest difference between groups was for the ipsilateral AAW tests for the comparison of NH with moderate SNHL for the BBN activator. This difference was approximately 20 dB for the AAW tests and 8 dB for the Clinical test. The ROC analysis showed that the area under the ROC curve (AUC) increased with the frequency of the activator stimulus and with the degree of hearing loss and was maximal for the BBN activator for both the AAW and Clinical methods for both ipsilateral and contralateral presentations.

For ipsilateral and contralateral ART tests for activator frequencies above 0.5 kHz and BBN, listeners with SNHL generally had elevated ARTs compared with those with NH. The AAW method resulted in greater differences between SNHL groups and NH than the Clinical method. The AUC for detecting SNHL also increased with activator frequency and degree of hearing loss and was greatest for the BBN activator for the AAW method in both the ambient and TPP conditions. The results are encouraging for the use of an AAW ART method for the assessment of individuals with SNHL.