O8 Contact heat evoked potentials of lower extremities – A feasibility study. Issue 9 (September 2017)

• Record Type: Journal Article
• Authors: Hubli, Michèle; Rosner, Jan; Hostettler, Pascal; Curt, Armin; Jutzeler, Catherine
• Is Part Of: Clinical neurophysiology. Volume 128:Issue 9(2017:Sep.)
• Page Start: e182
• Publication Date: 2017-09
• Subjects: Contact heat evoked potential -- Heat stimuli -- Small-fibre neuropathy -- Feasibility; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2017.07.019
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Objectives: Contact heat evoked potentials (CHEPs) present a non-invasive technique to study thermo-nociceptive pathways. Eliciting CHEPs from the lower extremities, particularly from the dorsum of the foot, has so far been considered to be rather difficult and poorly reproducible. Therefore, the goal of this study was to assess the feasibility and reliability of CHEPS from lower extremities in healthy subjects. Methods: Two stimulation protocols, i.e., normal and increased baseline protocol, were applied in 32 healthy subjects. The study protocol consisted of unilateral assessments of warm detection- and heat pain thresholds, followed by CHEPs recordings. Stimulation sites were the L2, L5, as well as the S2 dermatomes. CHEPs were recorded as vertex potentials from the Cz electrode. Results: Contact heat stimulation of the L2, L5 and S2 dermatome reliably elicited cortical N2P2 components. While the amount of evoked potentials for the dermatomes L2 and S2 was close to 100% in both stimulation protocols, the proportion of EPs in the most distal dermatome, i.e., L5, was improved by 13% with the increased baseline stimulation protocol. The increased baseline stimulation protocol led to decreased N2 latencies, increased N2P2 amplitudes and improved test-retest reliability. Discussion/Conclusion: CHEPs recordings from the lower extremities could be reliably recorded from the lower extremities and were markedly improved by using an increased baseline protocol.The establishment of normative data will be meaningful for improving the applicability of CHEPS for the diagnosis of small-fibre neuropathies. Significance: CHEPs might be used as non-invasive assessment for small-fibre neuropathies.