Prognostic Significance of Somatosensory Potentials Evoked by Stimulation of the Median and Posterior Tibial Nerves: A Prospective 1-Year Follow-Up Study in Patients with Supratentorial Cerebral Infarction

Abstract

A prospective 1-year follow-up examination was carried out in 35 patients with supratentorial cerebral infarction. The median nerve SEPs were performed 3-15 days and the tibial nerve SEPs 4-19 days after the stroke. The functional outcome was assessed 1 year after the stroke. The occupational outcome correlated most closely with the amplitude abnormalities (absence or attenuation) and with the overall abnormality in the tibial nerve SEPs. The ability to cope with activities of daily living was associated significantly with motor signs in the neurological examination performed during the acute stage, and nearly significantly with the presence or absence of the N60 wave in the median nerve SEPs. Both the tibial nerve SEPs and the motor signs correlated nearly significantly with the presence of neurologic signs or symptoms 1 year after the stroke. The prognostic information provided by the clinical examination and the SEPs is thus qualitatively different and complementary. More prognostic information could be gained by the use of both tibial nerve and median nerve SEPs than by the use of median nerve SEPs only; in the present series of patients the tibial nerve SEPs even had a greater prognostic value than the median nerve SEPs.