[Changes in somatosensory evoked potentials in carotid desobliteration. Diagnostic significance and possible...

The cerebral function of 55 patients with stenosis and occlusion of carotid arteries was monitored intraoperatively by serial examination of somatosensory cortical evoked potentials (SEP). In 40 uncomplicated operations no significant alteration of the SEP was detected. In 13 examination series, however, reversible abnormalities were noted. Furthermore, in two cases irreversible SEP loss was documented. The nature and temporal development of SEP alterations enabled differentiation of possible etiological factors. Bilateral abnormalities were indicative of global hypoxemia whereas acutely arising unilateral SEP loss suggested embolic occlusion of cerebral arteries. Intraoperative SEP monitoring therefore appears to be of diagnostical and differential diagnostical value and allows statements in respect to further intra- and postoperative treatment.