Correlation Between Functional and Electrophysiological Recovery in Acute Ischemic Stroke

Abstract

Background and Purpose-There is still controversy about the prognostic value of motor evoked potentials (MEPs) in the assessment of hemiplegia. The aims of this study are to determine the relationship between functional and electrophysiological recovery and thus the value of MEP as a prognostic indicator of clinical outcome in acute ischemic stroke. Methods-Seventeen healthy subjects and 38 stroke patients were included in this study. Functional recovery was assessed with the Modified Canadian Neurological Scale (MCNS), the Barthel Activities of Daily Living Index (BI), and the Rankin scale. Transcranial magnetic stimulation was used to determine the change in central motor conduction time (CMCT). Stroke outcome was assessed at the end of 2 weeks. One-way ANOVA with post hoc comparisons using the Scheffé procedure as well as t tests were used to assess the significance of the results in this study. Results-Unpaired t test showed significantly higher mean scores of the MCNS (2Pϭ0.001), BI (2Pϭ0.002), and Rankin scale (PϽ0.001) at day 14 in the group of patients with recordable MEP at day 1. A better clinical improvement with a higher mean score of the MCNS (2PϽ0.001), BI (2PϽ0.001), and the Rankin scale (2PϽ0.001) was also observed in the patients in whom the CMCT improved. Conclusions-These data show that there is a close relationship between clinical and electrophysiological improvement and that MEP is a useful prognostic indicator of clinical outcome.

Comparison of the Effects of 1 Hz and 20 Hz rTMS on Motor Recovery in Subacute Stroke Patients

“…Low frequency stimulation to the intact cerebral hemisphere can significantly improve upper motor limb function in chronic stroke patients [13]. Due to both seizure risk and unproven efficacy, some researchers argue that rTMS on the primary motor cortex of the ipsilesional cerebral hemisphere should be better understood and researched before implementation [24]. However, recent research shows that high frequency rTMS is safe for adults, adult stroke patients, and even children [12,25,26].…”

TMS-evoked N100 responses as a prognostic factor in acute stroke

“…Transcranial magnetic stimulation (TMS) is a neurophysiological technique widely used to investigate the functional state of the human cerebral cortex and corticospinal tract. It has been employed in the acute phase of stroke to evaluate the capability of the primary motor cortex to reorganize itself in order to recover functionality (Di Lazzaro et al, 1999;Hendricks et al, 2002;Vang et al, 1999). TMS variables, such as the presence or absence of the motor evoked potential (MEP) and the motor threshold, may be prognostic indicators of motor and functional recovery, particularly in people presenting with initial severe paresis (Hallet, 2000;Talelli et al, 2006;Thickbroom et al, 2002Thickbroom et al, , 2004.…”

Early prediction of functional outcome after stroke

“…Short central motor conduction time and relatively high amplitude of motor evoked potentials (MEP) on the affected hand are correlated with a favourable outcome. Particularly, the absence of MEP at the first day post-stroke is regarded as a sign of poor functional outcome [9][10][11][12].…”