[Somatosensory evoked potentials in the acute phase of focal cerebral ischemia].

Abstract

The authors made 38 examinations of the somatosensory evoked potentials of the median nerve (SEP) in 28 patients in the acute stage of focal cerebral ischaemia (20 men, 8 women mean age 62 years; range 28-81). According to the clinical and CT picture the patients were divided into two groups: affections in the carotid vessels (22 patients) and in the vertebrobasilar vessels (6 patients). The investigated parameters comprised the so-called central conduction time (interval N13-N19) and amplitude N19/P22. The highest incidence of abnormalities was in the group of vertebrobasilar ischaemias (83%), while in the group of ischamias in the carotid vessels it amounted only to 50%. In both the central conduction time as well as amplitude N19/P22 were effected. In the group of focal ischaemias the authors did not find a close correlation between the carotid circulation and the sensory deficit, but recorded a correlation between the affection of SEP and the resultant condition: in patients without SEP abnormalities complete restoration of the condition predominated (63%), while in the group with pathological findings during the SEP examination complete restoration was recorded only in 9%. Repeated (dynamic) evaluations and the relationship between the ischaemic focus and the somatosensory pathway are important.