Author/Editor		Prestor, B; Dolenc, VV
Title		Neurophysiological characteristics of the cervical spinal cord observed during DREZ-treatment
Type		članek
Source		In: Kepplinger B, Pernak JM, Ray AL et al, eds. Pain - clinical aspects and therapeutical issues. Part 2. Linz: Edition Selva Verlag,
Publication year		1993
Volume		str. 8-16
Language		eng
Abstract		Fourteen patients with intractable deafferentation pain underwent junctional DREZ coagulation lesions. Intra-operative neuromonitoring by recording sensory and motor spinal cord evoked potentials was carried out using subpial recording electrodes situated dorsal to the posterior median sulcus. After tibial nerve stimulation, subpial SSCEP on the normal side showed an initial positive wave, followed by several distinet negative waves, a group of high amplitude conducted potentials and a group of low amplitude conducted potentials. Recordings from the side of the avulsion revealed a steep positive potential of high amplitude, which appeared prior to the creation of a DREZ lesion. This was the incomplete spinal cord evoked injury potential and was assumed to be secondary to spinal cord damage caused by the avulsion. During the DREZ microcoagulation, we noted two particular features in our patients; namely, disappearance of the negative components after the initial positive wave, and appearance of the spinal cord evoked injury potential. Disappearance of negative components suggested that the spinocerebellar pathway had been affected and also, to a smaller extent, the dorsal columns system. The appearance of positive injury potential signified a more extensive spinal cord lesion. With respect to the MSCEP the changes in electrophysiologic characteristics of the potentials during DREZ coagulation were D wave amplitude decrease and disappearance of waves. This was indiciative of incomplete corticospinal tract damage. Our results point to the usefulness of the subpial sensory and motor tract evoked potential neuromonitoring during microneurosurgical procedures on the spinal cord to provide further insight into evoked electrical activity of the normal and injured spinal cord, and to minimize post-operative neurological morbidity.
Descriptors		PAIN, INTRACTABLE EVOKED POTENTIALS, SOMATOSENSORY SPINAL NERVE ROOTS INTRAOPERATIVE MONITORING