摘要
目的建立接触性热痛诱发电位(CHEP)的检测方法,估测介导此诱发电位的外周神经传导速度。方法受试者取卧位,应用 CHEP 刺激器,于两个强度水平(49.5℃和54.5℃)应用可调节脉冲,刺激部位为鱼际肌、手背、前臂的掌侧面。受试者在每次刺激后,按照视觉模拟评分标准对刺激强度分级。以 Keypoint 仪器记录,记录点为 Cz 和 Pz。测定刺激强度和疼痛分级的关系、诱发电位的主要成分及外周神经传导速度。结果刺激强度和疼痛分级的关系为:49.5℃和54.5℃刺激鱼际肌皮肤,疼痛分级分别为(3.2±0.3)、(4.4±0.5)级;54.5℃刺激手背和前臂掌侧面皮肤,疼痛分级分别为(6.3±0.8)、(7.2±0.5)级。于记录点记录到3个主要成分:Cz/N550、Cz/P750和 Pz/P1000。介导此诱发电位的外周神经传导速度分别为(12.9±7.5)、(1.7±0.4)m/s,分别与 Aδ纤维和 C 纤维的传导速度相对应。结论 CHEP 能较为稳定、可靠地引出,介导此诱发电位的外周神经为Aδ纤维和 C 纤维。
Objective To evoke cerebral potentials by stimulating nociceptive fibers with contact heat evoked potentials stimulator （CHEPS）and estimate the nerve conduction velocities of peripheral nerve fibers mediating these responses. Methods Subjects were set in supine position. A heat-foil technology with a rapid rising speed at 70℃/s was used to elicit pain and contact heat evoked potentials（CHEP）. Contact heat was delivered via one circular thermode （diameter 27 mm, area 573 mm^2 ）. Thermal stimuli were sent at two intensity levels （49. 5℃ and 54. 5℃ ） to three body sites ： thenar eminence, the dorsum of hand and proximal volar forarm. Contact heat evoked potentials were recorded from Cz and Pz. A systemic effect between stimulus intensities and pain rating were observed, the main components of this evoked potential were observed. Nerve conduction velocity was calculated from latency difference of CHEP and center to center distance of distal and proximal stimulus arrays. Results The pain intensity rating was 3.2 ± 0. 3 and 4. 4 ± 0. 5 when thenar eminence was stimulated at the temperature of 49. 5 ℃ and 54. 5℃ respectively; the rating was 6. 3 ± 0. 8 and 7.2 ± 0. 5 when the dorsum of hand and proximal volar forarm were stimulated at the temperature of 54. 5 ℃ respectively. Three components, Cz/N550, Cz/P750 and Pz/P1000, were found in the evoked potentials. Nerve conduction velocities of the fibers were （ 12. 9 ±7.5） and （ 1.7 ±0. 4） m/s respectively, which were corresponding to those of Aδ fiber and C fiber. Conclusions CHEPs can be elicited reliably and stably. Velocities of peripheral nerve fibers demonstrate that Aδ fiber and C fiber mediate the response.
出处
《中华神经科杂志》
CAS
CSCD
北大核心
2007年第2期129-132,共4页
Chinese Journal of Neurology
关键词
热
疼痛感受器
诱发电位
躯体感觉
神经传导
神经纤维
Heat
Hociceptors
Evoked potentials, somatosensory
Neural conduction
Nervefibers, unmyelinated
