Wolf S L, Cohen B A
Arch Phys Med Rehabil. 1977 Mar;58(3):127-32.
Repeated impedance measurements of electrical stimulation to the finger using the stimulator of an electromyograph were evaluated in seven normal subjects to determine whether reliable threshold values to perception of pain could be obtained. Stimuli were delivered through ring or disc electrodes separated by 3 cm and interfaced to the skin of the digit with EKG paste. Stimulation through these electrodes produced only relative values of threshold, expressed as a potentiometer dial setting. Such values proved to be meaningful only when repeated during a single session. A possible reason for the apparent unreliability of repeated measurements over time is discussed. When a constant current source was substituted, reliable and consistent threshold measurements were obtained. It is suggested that the clinician wishing to make accurate, repeatable and quantified measurements of patient thresholds to electrical stimulation of the finger employ a nonloading source, namely, a constant current or constant voltage stimulator.
使用肌电图仪的刺激器对七名正常受试者的手指进行电刺激的重复阻抗测量，以确定是否能够获得可靠的疼痛感知阈值。刺激通过相距3厘米的环形或圆盘电极传递，并用心电图粘贴剂连接到手指皮肤。通过这些电极进行的刺激仅产生阈值的相对值，以电位计刻度盘设置表示。这些值仅在单次测量期间重复时才有意义。讨论了随着时间推移重复测量明显不可靠的一个可能原因。当使用恒流源替代时，获得了可靠且一致的阈值测量结果。建议希望对手指电刺激的患者阈值进行准确、可重复和定量测量的临床医生使用无负载源，即恒流或恒压刺激器。
