Patterns of contact heat evoked potentials (CHEP) in neuropathy with skin denervation: Correlation of CHEP amplitude with intraepidermal nerve fiber density
Journal
Clinical Neurophysiology
Journal Volume
119
Journal Issue
3
Pages
653-661
Date Issued
2008
Author(s)
Abstract
Objective: Contact heat evoked potentials (CHEPs) provide an objective approach to investigate cerebral responses to thermal stimuli mediated by Aδ fibers. Skin denervation is often associated with reduced thermal sensibilities. We aimed to investigate the influences of skin denervation on CHEPs in neuropathic patients. Methods: CHEPs were recorded at the vertex area by applying contact heat stimuli of 51 °C on the distal leg of neuropathic patients with sensory symptoms and pathological evidence of skin denervation in the distal leg. Patterns and parameters of CHEPs in the neuropathic group were compared with those in the control group of age- and gender-matched subjects. Results: There were 25 neuropathic patients with reduced intraepidermal fiber (IENF) density (1.46 ± 1.70 fibers/mm, range: 0-5.32). In the control group, well-defined averaged tracings of CHEPs with an initial negative peak (N-wave) followed by a positive peak (P-wave) were consistently recorded in all 25 subjects. The peripheral conduction velocities of CHEPs were 9.92 ± 4.06 m/s (range: 6.06-16.60), in the range of Aδ fibers. The group of neuropathic patients had markedly reduced N-P amplitudes (p < 0.0001) and prolonged N-wave latencies (p = 0.049) compared to the control group. IENF density was the only neuropathic parameter correlated with N-P amplitude on multiple linear regression analysis (p = 0.010) compared to large-fiber parameters. Conclusions: In neuropathic patients with pathological evidence of skin denervation, there were reduced amplitude and prolonged latencies in CHEPs mediated by Aδ fibers. The reduction of CHEP amplitude corresponded to the degree of skin denervation. Significance: CHEP offers electrophysiological evidence of thermal responses and provides an objective, non-invasive approach to assess the physiological counterparts of skin denervation in neuropathic patients. ? 2007 International Federation of Clinical Neurophysiology.
SDGs
Other Subjects
cisplatin; etoposide; adult; aged; article; clinical article; controlled study; denervation; evoked response; female; human; human tissue; male; nerve conduction; nerve fiber; neuropathy; priority journal; skin biopsy; Adult; Aged; Electric Stimulation; Electromyography; Epidermis; Evoked Potentials, Somatosensory; Female; Heat; Humans; Male; Middle Aged; Neural Conduction; Peripheral Nervous System Diseases; Reaction Time; Retrospective Studies; Ubiquitin Thiolesterase
Type
journal article