Objective: To assess the predictive value of median somatosensory evoked potentials (SSEP) in the acute phase of brain infarction or hemorrhage regarding long-term prognosis.
Materials and methods: Ninety-four stroke patients mean age 61.2, SD 11.8) were included. CT confirmed diagnoses were: cortical middle cerebral artery (MCA) infarction in 35; subcortical MCA 11; mixed 25. By size, infarctions were: massive, 29; restricted, 33; and lacunar, 9. The number of patients with thalamic hemorrhage was 8; putamenal hemorrhage, 7; other, 8. All patients presented with severe hemiparesis (54) or hemiplegia (40) with hemihipoesthesia in 89 patients. Median SSEP were recorded early (up to 7th day, mean 5.2 days, SD 0.72). SSEP parameters (presence/absence of SSEP, absolute and relative latency, amplitude of early waveforms) were compared to motor (Medical Research Council scale) and functional ability (Barthel index) at 3 and 12 months after stroke.
Results: Absolute N20 amplitudes and amplitude ratio evidenced almost similar predictive values that reached 66.4% at 12 months. Combined application of N20 and MRC gains provided significantly stronger prognostic information which reached 72%.
Conclusions: Median SSEP parameters may serve as independent predictors of outcome. Most informative in prognosis in the early stage of stroke was the combined assessment of MRC and N20-P25 amplitude ratio.