Original Research Article
Year: 2019 | Month: November | Volume: 6 | Issue: 11 | Pages: 597-605
A Study of Cervical Vestibular Evoked Myogenic Potential (cVEMP) in Indian Adults with Normal Hearing
Dilip Raghavan1, Sheetal Raina2, DK Singh3, Salil Kumar Gupta2, Vijay Bhalla4, Abha Kumari2
1Professor and Head, Dept pf ENT& HNS, Armed Forces Medical College, Pune, Maharashtra, India - 411040
2Assistant Professor, 3Associate Professor,
Department of ENT & HNS, Command Hospital (Eastern Command), Kolkata, West Bengal, India - 700027
4Professor, Department of ENT & HNS, Base Hospital (Delhi Cantt), New Delhi, India - 110010
Corresponding Author: Sheetal Raina
ABSTRACT
Introduction – Vestibular Myogenic Potential (VEMP) is a newer modality to partially assess otolithic organs by assessing the functions of saccule and its neural connections. Cervical and Ocular VEMP are being studied extensively for its anticipated objective utility in diagnosing vestibulopathies. With the advent of various techniques of conduct and interpretation of VEMP there is a felt need to obtain and standardise the normative data in Indian population. This observational descriptive study peruses three objectives - Comparison of effect of different stimuli i.e. click vs. short tone burst & unilateral vs. bilateral stimulation in generation of cVEMP; to study the effect of mode of muscle contraction on cVEMP i.e. head lift vs. neck torsion, and, to study age & gender related variations in generation of these potentials.
Methods – 171 healthy adult volunteers between 18 – 25 years of age with normal hearing were recruited and subjected to cVEMP testing. cVEMP was performed by head lift and neck torsion manoeuvre and with short tone burst (95 dBnHL, 500 Hz) (STB) and clicks and data was recorded and analysed.
Results – Statistically significant amplitudes (in µV) for both waveforms, p13 and n23, were recorded with head lift manoeuvre as compared to neck torsion and STB stimulus as compared to clicks. Latencies of waveform p13 and n23 were significantly shorter for click stimuli compare to Short tone burst stimulus. We found no statistically significant variation in amplitudes and latencies of both waveforms among both genders.
Conclusion – cVEMP can be reliably obtained by both click and short tone burst stimuli in normal hearing individuals. STB stimulus produces morphologically clearer responses with larger amplitudes than click stimuli while Click stimulus elicits a cVEMP with shorter latencies than STB. Head lift manoeuvre was a reliable means of producing Sternocleidomastoid contraction while neck torsion was not. There was no gender variation in terms of amplitudes and latencies of cVEMP waveforms.
Key words: Cervical Vestibular Evoked Myogenic Potentials, head lift maneuver, neck torsion maneuver, p13-n23, amplitudes, latencies
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