Activation of C-fiber nociceptors by low-power diode laser

• Autor(es): Azevedo,Eduardo ; Silva,Andressa ; Martins,Raquel ; Andersen,Monica L. ; Tufik,Sergio ; Manzano,Gilberto M.
• Data: 2016
• Origem: Oasisbr
• Assunto(s): laser-evoked potentials; C-fibers; nociception; pain perception
• Tipo de Documento: Artigo científico
• Idioma: Inglês

Descrição

ABSTRACT Objective The evaluation of selective activation of C-fibers to record evoked potentials using the association of low-power diode laser (810 nm), tiny-area stimulation and skin-blackening. Method Laser-evoked potentials (LEPs) were obtained from 20 healthy young subjects. An aluminum plate with one thin hole was attached to the laser probe to provide tiny-area stimulation of the hand dorsum and the stimulated area was covered with black ink. Results The mean intensity used for eliciting the ultra-late laser-evoked potential (ULEP) was 70 ± 32 mW. All subjects showed a clear biphasic potential that comprised a negative peak (806 ± 61 ms) and a positive deflection (1033 ± 60 ms), corresponding to the ULEP related to C-fiber activation. Conclusion C-fiber-evoked responses can be obtained using a very low-power diode laser when stimulation is applied to tiny areas of darkened skin. This strategy offers a non-invasive and easy methodology that minimizes damage to the tissue.