RELATIONSHIP BETWEEN EVOKED-POTENTIALS AND CLINICAL STATUS IN SPINAL-CORD ISCHEMIA

Study Design and Methods. Sciatic neurogenic motor-evoked potentials, spinal evoked potentials, and somatosensory-evoked potentials were rec orded in 12 anesthetized dogs that had arterial ischemia of the lumbar cord produced by ligation of segmental arteries. The presence or abse nce of the above-mentioned potentials was compared with the clinical s tatus of repeated wake-up tests. Results. Although these results were complicated, sciatic neurogenic motor-evoked potential was more sensit ive to the spinal cord ischemia and was a better predictor of clinical outcome than spinal evoked potential and somatosensory-evoked potenti al. However, the 1 presence was not a guarantee of normal function. Th e initial morphologic change of these potentials secondary to ischemia consisted of a decrease in amplitude and in the number of peaks witho ut a shift of latency. Conclusions. The present study suggests that th e peripheral neurogenic motor-evoked potential is a better warning sys tem for spinal cord ischemia and that its adoption may contribute to t he prevention of cord ischemia during spinal surgery, whereas somatose nsory evoked potential and spinal evoked potential cannot be indices.