ثبت پتانسيل هاي با منشا عضلاني برانگيخته از وستيبول VEMP و بررسي تاثير نوع محرك بر آن در افراد طبيعي بزرگسال

Recording "Vestibular-Evoked Myogenic Potentials" (VEMP) and Effects of Various Types of Stimulus on Them amongst Normal Adult Subjects

Background: Vestibular evoked myogenic potentials (VEMP) are short-latency electromyograms (EMG) evoked by high-level acoustic stimuli that recorded from surface electrodes over the contracted sternocleidomastoid (SCM) muscle and are presumed to originate in the saccule. The goal of present study was recording the VEMP response and determining the effects of stimulus type (click and tone bursts) on itʹs results in a group of normal adult subjects. Materials and Methods: In this cross-sectional analytical study the effects of click and tone burst stimuli on latency and amplitude of VEMP recording were examined by simple randomized sampling over 30 adults subjects ranging in age from 25 to 35 years with normal hearing sensitivity and no history of vestibular disease. Results: VEMP recorded in all subjects using 95 dBnHL tone burst stimuli, and in 26 subjects with click stimulus in the both ears. The response amplitude of VEMP with tone burst stimuli was better than click stimulus, and the largest amplitude was obtained by 500 Hz stimulus frequency. VEMP latency was independent of stimulus type and frequency. Conclusion: Type and frequency of stimulus do not affect VEMP response, and use of 500 Hz tone burst stimulus reveals the largest amplitude, that can be considered in clinical applications.