ID 267 – Vestibulo-masseteric reflex and acoustic-masseteric reflex: Normative values. Issue 3 (March 2016)

• Record Type: Journal Article
• Authors: de Natale, E.R.; Ginatempo, F.; Pilurzi, G.; Ortu, E.; Mercante, B.; Manca, A.; Magnano, I.; Tolu, E.; Rothwell, J.C.; Deriu, F.
• Is Part Of: Clinical neurophysiology. Volume 127:Issue 3(2016:Mar.)
• Page Start: e68
• Publication Date: 2016-03
• Subjects: Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2015.11.227
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Objective: To provide normative values on the vestibulo-masseteric (VMR) and acoustic-masseteric reflexes (AMR) for age/gender groups. Methods: Sixty healthy volunteers (27 males, 33 females; 45.8 ± 17.4 years old), divided in 6 age groups (<25 years, 26–35, 36–45, 46–55, 56–65, >65 years), underwent click-evoked VMR (p11 wave) and AMR (p16/n21 wave). Zygomatic and mandibular electrode-montages and intensity-thresholds (98-138 dB SPL, at 5 dB intervals) were tested. Results: For unilateral stimulation, peak-latency values were: p11 = 11.42 ± 1.05 ms; p16 = 15.81 ± 1.22 ms; n21 = 20.58 ± 1.74. Corrected amplitudes were: p11 = 0.47 ± 0.18; p16/n21 = 0.49 ± 0.2. VMR and AMR were elicitable from 112/120 and 108/120 ears, respectively. Bilateral stimulation induced higher amplitudes compared with unilateral stimulation ( p < 0.0001 for both reflexes). With age, VMR and AMR p1-peak latencies increased (VMR: F 5, 59 = 7.004, p < 0.0001; AMR: F 5, 59 = 3.265, p = 0.012) whereas only VMR amplitude decreased ( F 5, 59 = 3.742, p = 0.003). The p1-peak latencies were shorter in females than males (VMR: p = 0.009; AMR: p = 0.002). Optimal thresholds were <113 dB for the AMR and >128 dB for the VMR. The zygomatic montage was associated to higher amplitudes (VMR: p = 0.034; AMR: p = 0.004). Conclusions: VMR and AMR behave similarly to commonly used myogenic potentials. Key message: Characterization of VMR and AMR in normal subjects adds value for their use in clinical settings where they are increasingly used to assess brainstem function.