Kirshblum S, Cai P, Johnston M V, Shah V, O'Connor K
Spinal Cord Injury Services, Kessler Institute for Rehabilitation, West Orange, NJ, USA.
Arch Phys Med Rehabil. 1998 Sep;79(9):1059-61. doi: 10.1016/s0003-9993(98)90171-x.
To determine whether F-wave results differ with the anode proximal or distal to the cathode, ie, if clinical anodal block exists.
Prospective study of 30 healthy volunteers undergoing nerve conduction and F-wave studies in one median nerve. A needle cathode electrode was used with a surface anode placed alternately proximal and distal to the cathode. The same electromyographer performed all studies with a Dantec Counterpoint machine.
F-wave latencies were essentially unaffected by distal versus proximal positioning. Minimum, maximum, and mean F-wave latencies correlated extremely highly (r=.973 to .988). For both F-wave and M-response latencies and amplitudes, differences between mean values obtained using the two methods were extremely small and were neither clinically nor statistically significant. The frequency of elicitation of F-waves may (p < .05) have been slightly (3.5%) lower when the anode was in the distal position.
Anodal block is not seen in F-wave studies when using needle electrode stimulations. Reversing the stimulator does not seem to be required. Further study with surface stimulating electrodes is underway to confirm results.
确定当阳极位于阴极近端或远端时F波结果是否不同，即是否存在临床阳极阻滞。
对30名健康志愿者进行前瞻性研究，对其一条正中神经进行神经传导和F波研究。使用针状阴极电极，表面阳极交替置于阴极的近端和远端。同一名肌电图检查人员使用丹泰克对位仪器进行所有研究。
F波潜伏期基本上不受远端与近端定位的影响。最小、最大和平均F波潜伏期高度相关（r = 0.973至0.988）。对于F波和M反应潜伏期及波幅，两种方法获得的平均值之间差异极小，在临床和统计学上均无显著意义。当阳极位于远端位置时，F波引出频率可能（p < 0.05）略低（3.5%）。
使用针电极刺激进行F波研究时未观察到阳极阻滞。似乎不需要反转刺激器。正在进行使用表面刺激电极的进一步研究以证实结果。
