WITHDRAWN: [Significance of Stapedius Muscle Reflex Measurement in Diagnosing Auditory Processing Disorders.]

BACKGROUND: Stapedius muscle reflexes (SMR) are among the objective procedures which are used in the diagnostics of auditory processing disorders (APD). The significance of SRM for APD-diagnosis is open up to now. METHOD: Twenty-six children (8 - 10 years) with diagnosed APD and a control group of 17 children the same age were examined in order to determine whether differences with regard to the mean SMR (sine tones or band pass noise) exist between groups. In addition, differences between groups were investigated regarding the mean difference between the reflex thresholds for sine tones and the thresholds for band pass noises. RESULTS: Significant differences between groups existed in the mean value ipsilateral with 500 Hz, 1 kHz, 4 kHz and low bandpass noise as well as contralateral with 500 Hz. The contralateral measurements using sine tones (500 Hz, 1 kHz, 2 kHz and 4 kHz) showed reflex thresholds of about 100 dB only in the APD group. The results of the remaining types of stimulation showed a more or less distinctive area of overlap between the APD-group and the control group without the possibility of definite classification to a particular group. Group differences in the mean value with regard to the reflex thresholds for sine tones and the thresholds for band pass noises appeared only in low frequency stimuli. However, the area of overlap between the APD group and the control group in other frequencies was very large. CONCLUSION: Elevated thresholds measured in contralateral SMRs seem to support the assumption of APD. In contrast, the results of SMRs using ipsilateral measurements as well as low or high pass filtered noises contribute little toward diagnosing an APD. This applies identically to the difference between the reflex thresholds on sine tones and the thresholds on band-pass noises.