The effect of bone vibrator coupling method on the neonate auditory brainstem response.

The purpose of this study was to examine the effect of three bone vibrator coupling methods on the neonate auditory brainstem response (ABR). A repeated measures design was employed. Three coupling techniques were utilised (i.e. hand-held, hand-held applied force gauge and elastic band). ABRs were evoked with a bone-conducted 30 dB nHL 4000 Hz CE-Chirp octave band stimulus. A temporal bone area supero-posterior auricular position for bone vibrator placement was utilised. Twenty-six healthy full-term neonates participated. Replicated ABRs were recorded from all neonates for each coupling method. There was a statistically significant effect of coupling on wave V latency (p < 0.001) and amplitude (p < 0.001). There was no statistical difference between the elastic band and the hand-held force gauge coupling for wave V latency and amplitude (p > 0.05). However, the hand-held coupling method produced significantly longer wave V latency and smaller amplitude versus the elastic band and hand-held force gauge (p < 0.001). Bone vibrator coupling method affects the neonate ABR. Clinicians should be consistent with the choice of coupling while delivering controlled bone-conducted stimuli in ABR assessments in neonates and infants.