Nezu A, Kimura S, Takeshita S, Osaka H, Tanaka M
Department of Pediatrics, Urafune Hospital of Yokohama City University, School of Medicine, Yokohama, Japan.
Electroencephalogr Clin Neurophysiol. 1998 Sep;108(5):446-8. doi: 10.1016/s0168-5597(98)00018-5.
To evaluate conduction abnormalities of the corticospinal tracts (CSTs) in Pelizaeus-Merzbacher disease (PMD), magnetic stimulation at three levels was carried out in 3 boys with PMD aged between 9 and 12 years. They were all diagnosed as having a duplicated proteolipid protein gene. The motor cortex and cervical spinal roots were stimulated with a round coil, whereas a double cone coil was used for brain-stem stimulation. Surface electromyographic (EMG) recording was performed on the first dorsal interosseous muscles. Despite a normal EMG response to cervical stimulation, magnetic shock of the motor cortex elicited no EMG activity, even in the case with less motor symptoms. This discrepancy between the electrophysiological and clinical findings is likely due to slowing conduction, which reduces the temporal summation of multiple descending volleys magnetically elicited. A partial conduction block may also occur because of the lack of an EMG response to brain-stem stimulation. Thus, we speculated that the spastic paresis in PMD is associated with both slowing conduction and a partial conduction block in the CSTs.
为评估佩利措伊斯-梅茨巴赫病（PMD）中皮质脊髓束（CSTs）的传导异常，对3名年龄在9至12岁的PMD男孩进行了三个水平的磁刺激。他们均被诊断为具有重复的蛋白脂质蛋白基因。用圆形线圈刺激运动皮层和颈神经根，而用双锥线圈进行脑干刺激。在第一背侧骨间肌上进行表面肌电图（EMG）记录。尽管对颈部刺激的EMG反应正常，但即使在运动症状较轻的情况下，运动皮层的磁刺激也未引发EMG活动。电生理和临床结果之间的这种差异可能是由于传导减慢，这减少了磁诱发的多个下行冲动的时间总和。由于对脑干刺激缺乏EMG反应，也可能发生部分传导阻滞。因此，我们推测PMD中的痉挛性轻瘫与CSTs中的传导减慢和部分传导阻滞均有关。
