Kong Xuan, Lesser Eugene A, Megerian J Thomas, Gozani Shai N
NeuroMetrix, Inc, 62 Fourth Avenue, Waltham, MA 02451, USA.
J Clin Monit Comput. 2006 Dec;20(6):405-10. doi: 10.1007/s10877-006-9046-8. Epub 2006 Sep 14.
To quantify nerve conduction study (NCS) reproducibility utilizing an automated NCS system (NC-stat, NeuroMetrix, Inc.).
Healthy volunteers without neuropathic symptoms participated in the study. Their median, ulnar, peroneal, and tibial nerves were tested twice (7 days apart) by the same technician with an NC-stat instrument. Pre-fabricated electrode arrays specific to each nerve were used. Both motor responses (compound motor action potential [CMAP] and F-waves - all nerves) and sensory responses (sensory nerve action potentials [SNAP] - median and ulnar nerves only) were recorded following supramaximal stimuli. Automated algorithms determined all NCS parameters: distal motor latency (DML), mean F-wave latency (FWL), distal sensory latency (DSL), CMAP amplitude, and SNAP amplitude. Latency was adjusted for skin temperature deviation from reference. Pearson correlation coefficient (CC), intraclass correlation coefficient (ICC), coefficient of variance (CoV), and relative intertrial variation (RIV) were calculated.
Fifteen subjects participated in either upper or lower extremity studies with nine participating in both. With the exception of CMAP amplitude, all parameters had CoV less than 0.06. Upper extremity amplitude parameters had CCs greater than 0.85. CCs for latencies were greater than 0.80 except for the median nerve FWL (CC = 0.69). For lower extremity nerves, ICCs were highest for mean FWL (>0.90), followed by DML (>0.82) and then CMAP (peroneal 0.33, tibial 0.73). The 10th to 90th RIV percentiles were bounded by +/-7% for F-wave latencies; +/- 9% for all DSLs; and +/- 11% for DML (except peroneal at 15%).
The reproducibility of NCS parameters obtained with an automated NCS instrument compared favorably with traditional electromyography laboratories. F-wave latencies had the highest repeatability, followed by DML, DSL, SNAP and CMAP amplitude. Given their high reproducibility, automated NCS instrument may encourage wider utilization of NCS in clinical and research applications.
使用自动神经传导研究系统（NC-stat，NeuroMetrix公司）对神经传导研究（NCS）的可重复性进行量化。
无神经病变症状的健康志愿者参与了该研究。同一名技术人员使用NC-stat仪器对他们的正中神经、尺神经、腓总神经和胫神经进行了两次测试（间隔7天）。使用了针对每条神经的预制电极阵列。在超强刺激后记录运动反应（复合肌肉动作电位[CMAP]和F波 - 所有神经）和感觉反应（感觉神经动作电位[SNAP] - 仅正中神经和尺神经）。自动算法确定所有NCS参数：远端运动潜伏期（DML）、平均F波潜伏期（FWL）、远端感觉潜伏期（DSL）、CMAP波幅和SNAP波幅。根据皮肤温度与参考值的偏差对潜伏期进行调整。计算了Pearson相关系数（CC）、组内相关系数（ICC）、变异系数（CoV）和相对试验间变异（RIV）。
15名受试者参与了上肢或下肢研究，其中9名同时参与了上下肢研究。除CMAP波幅外，所有参数的CoV均小于0.06。上肢波幅参数的CC大于0.85。潜伏期的CC大于0.80，但正中神经FWL除外（CC = 0.69）。对于下肢神经，平均FWL的ICC最高（>0.90），其次是DML（>0.82），然后是CMAP（腓总神经为0.33，胫神经为0.73）。F波潜伏期的第10至90百分位RIV范围为±7%；所有DSL为±9%；DML为±11%（腓总神经为15%除外）。
与传统肌电图实验室相比，使用自动NCS仪器获得的NCS参数具有良好的可重复性。F波潜伏期的重复性最高，其次是DML、DSL、SNAP和CMAP波幅。鉴于其高可重复性，自动NCS仪器可能会促进NCS在临床和研究应用中的更广泛使用。
