Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
Clin Neurophysiol. 2018 Mar;129(3):584-591. doi: 10.1016/j.clinph.2017.12.034. Epub 2018 Jan 7.
To investigate test-retest reliability of contact heat evoked potentials (CHEPs) from lower extremities using two different stimulation protocols, i.e., normal and increased baseline temperature.
A total of 32 able-bodied subjects were included and a subset (N = 22) was retested. CHEPs were recorded from three different dermatomes of the lower extremity (i.e., L2, L5, and S2). Test-retest reliability of CHEPs acquisition after simulation in various lower limb dermatomes using different stimulation protocols was analyzed.
The study revealed an improved acquisition of CHEPS employing the increased baseline protocol, particularly when stimulating more distal sites, i.e., dermatome L5 and S2. Based on repeatability coefficients, CHEP latency (N2 potential) emerged as the most robust CHEP parameter. Although CHEP amplitudes (N2P2 complex) and pain ratings were decreased in the retest, amplitudes still showed fair to excellent intraclass correlation coefficients using normal baseline or increased baseline temperature, respectively.
This is the first study to demonstrate that CHEPs acquisition from the lower extremities is improved by increasing the baseline temperature of the thermode.
This study highlights the usability of CHEPs as a viable diagnostic method to study small fiber integrity.
使用两种不同的刺激方案（即正常和升高的基线温度），研究下肢接触热诱发电位（CHEPs）的复测可靠性。
共纳入 32 名健康受试者，其中一部分（N=22）进行了复测。CHEPs 分别从下肢三个不同的皮区（L2、L5 和 S2）记录。分析了在不同的下肢皮区使用不同的刺激方案进行模拟后，CHEPs 采集的复测可靠性。
研究显示，采用升高的基线方案可改善 CHEPS 的获取，特别是在刺激更远端的部位时，如皮区 L5 和 S2。根据可重复性系数，CHEP 潜伏期（N2 电位）是最稳健的 CHEP 参数。尽管在复测中 CHEP 振幅（N2P2 复合物）和疼痛评分降低，但使用正常基线或升高的基线温度时，振幅仍分别显示出相当好到极好的组内相关系数。
这是第一项研究表明，通过升高热刺激器的基线温度，可以改善下肢 CHEPs 的获取。
本研究强调了 CHEPs 作为研究小纤维完整性的可行诊断方法的可用性。
