抄録
Spinal cord monitoring during surgery by using SCEP has been shown to be superior to the wake-up test, because it enables the practitioner to determine the induced ischemia of the spinal cord more precisely and promptly before neural deficit develops into permanent. Surgical procedures have to be stopped when peak amplitude of N1 has decreased up to 50% of the control potentials. We have already successfully operated on 72 patients with spine deformity under it. The purpose of this paper is to introduce animal experiments which have given conclusion described above. The study was conducted in three parts. In the first part, injury experiment by distraction force was done. The spinal cord was impaired by longitudinal distraction using a special designed instrument. There was a certain degree of distraction which produced transient augumentation of the N2 amplitude without neural deficit. The N1 deflection always decreased more than 50% with paralysis immediately after continueing 4mm distraction. In the second part, intraspinal potentials were recorded using glass pipet electrodes in order to identify precise location of N1 and N2 in conductive SCEP. The N2 conducted in the dorsal column. N1, however, was compound potentials from the whole spinal cord. In the third part, ascending and descending pathways of N1 and N2 was determined by the collision test. It was strongly suspected that the N1 and N2 of ascending and descending conductive SCEP had common pathways.
