Clinical Usefulness of Somatosensory Evoked Potentials in Patients with Stroke

OBJECTIVE: To assess the usefulness of the somatosensory evoked potentials in correlating with various clinical features and in predicting the functional outcome in patients with stroke. METHOD: The subjects were 57 patients with first stroke. Somatosensory evoked potential study was performed at the time of transfer to the rehabilitation department. Data of somatosensory evoked potential with median and tibial nerve stimulations were obtained and classified as normal (group 1), abnormal (group 2), and no response group (group 3). Modified Barthel index (MBI), motor and sensory functions were evaluated at the time of transfer and discharge. RESULTS: MBI score was statistically different among the 3 groups based on the findings of median and tibial nerve SSEP at the time of transfer, but not different at the time of discharge. Motor function was statistically different among the 3 groups at the time of transfer and discharge. Sensory function was statistically different among the 3 groups at the time of transfer, but not different at the time of discharge. CONCLUSION: Even though SSEP study reflects the functional status of the patients and correlates well with the findings of brain image, it has limitation in predicting outcome of the patients with stroke.

Electrophysiologic Assessement of Axonopathy and Demyelination in Diabetic Neuropathy according to the Severity

OBJECTIVE: To assess the axonopathy and demyelination neuropathy according to the electrophysiologic severity in diabetic neuropathy. METHOD: Electrophysiologic data of 246 patients who had been diagnosed with diabetic neuropathy was obtained and classified into suspected, possible, and definite groups by the criteria of our laboratory. Nerve conduction study was performed in the median, ulnar motor and sensory nerves, peroneal and tibial motor nerves, and sural nerve. Statistics were done with the results from the median motor and sensory, tibial motor and sural nerves. According to the severity of diabetic neuropathy, correlation and Chi-square analysis between amplitudes and latencies were performed. RESULTS: Frequencies of diabetic neuropathy according to electrophysiologic severity were as follows: 24 cases of suspected, 141 cases of possible, and 81 cases of definite neuropathy. The correlation ratios between amplitude and latency were 0.41- 0.79 (p<0.05) in the definite group of all the nerves examined, and below 0.3 in the suspected and possible groups. By Chi-square analysis, amplitude reduction was the predominant finding in the suspected and possible groups.si CONCLUSION: In the early stage of diabetic neuropathy, axonopathy might be the preceding pathogenesis, while with progression of diabetic neuropathy, axonopathy and demyelination may coexist.