Using somatosensory evoked potential to predict functional recovery in the acute phase of stroke

Abstract

Objective To assess the predictive value of short-latency somatosensory evoked potential (SSEP) in the acute phase of stroke regarding functional recovery. Methods One hundred and fifty stroke patients were included. SSEPs were recorded on the first 7 days after stroke, and the patients were then stratified into groups with absent, abnormal and normal responses. Clinical state was determined according to the NIH stroke scale (NIHSS), the Fugl-Meyer assessment (FMA), the modified Barthel index (MBI) and the modified Rankin scale (MRS). SSEP was followed up at 1, 3, 6 and 12 months. Results The NIHSS and FMA scores were significantly different comparing any two groups or at different times in the same group. The median SSEP N20 latency and tibial nerve SSEP P40 latency during stroke were positively correlated with MRS scores 12 months later but negatively correlated with MBI results. The ADL results 12 months after stroke were used to evaluate functional recovery, and the prediction rate of the SSEP results alone was 40.8% , however the rate improved to 44.2% when SSEP results were combined with FMA scores and became 46.1% when SSEP, FMA and MRS results were all considered. Conclusion SSEP has independent predictive value regarding functional recovery after stroke. Combined assessment of initial FMA, MRS and SSEP substantially improves the predictive power for stroke prognosis. Key words: Stroke; Somatosensory evoked potential; Prognosis