SOMATOSENSORY EVOKED-POTENTIALS FOLLOWING STIMULATION OF MEDIAN AND TIBIAL NERVES IN PATIENTS WITH LOCALIZED INTRACEREBRAL HEMORRHAGE - CORRELATIONS WITH CLINICAL AND CT FINDINGS

Median and tibial somatosensory evoked potentials (SEPs) were performed on 38 patients with localized intracerebral hemorrhage, 23 with thalamic hemorrhage and 15 with putaminal hemorrhage. Of 65 arms and 62 legs examined, cerebral evoked responses of 60 arms and 50 legs were diagnosed as abnormal. The abnormal findings in scalp-recorded SEPs consisted of a reduction in amplitude, loss of waves and delay in peak latencies. The SEP abnormalities were not indicative of location of hemorrhage. Absence of SEPs was more frequently observed in large hemorrhages and at the early stage. Substantial improvement in SEPs was observed over several months after stroke in many limbs. Motor function as evaluated with Brunnstrom staging of the upper limbs whose SEPs were absent was lower than that whose SEPs were evoked, but that was not observed in the lower limbs because in some cases absence of SEPs coexisted with good motor function. Loss of SEP waves had a significant correlation with disturbed deep sensation. The median and tibial SEPs provided an excellent clinical correlation with the patients' improvement over several months.