Predictive value of motor-evoked potentials for motor recovery in patients with hemiparesis secondary to acute ischemic stroke

BACKGROUND: Motor recovery following a stroke is related to the initial stroke severity and corticospinal tract integrity. One of the outcomes representing corticospinal tract integrity is the motor evoked potential (MEP). This study aimed to investigate the predictive value of MEP for motor recovery in patients with acute ischemic stroke. PATIENTS AND METHODS: Patients with hemiparesis secondary to initial acute ischemic stroke were enrolled. MEPs of the upper limb were assessed as preserved (MEP+) or absent (MEP-) response ≤10 days post-stroke. Fugl-Meyer assessment (FMA) was performed at baseline and post-stroke at 30 and 90 days. A modified Rankin scale (mRS) was conducted at 90 days post-stroke. Patients were divided into two groups according to the highest FMA score of MEP- patients. Generalized estimating equations and logistic regression were used for our study analysis. RESULTS: Sixty-one participants were included in this study. The highest FMA score of MEP- patients ≤10 days after stroke was 38. Among patients with an initial FMA score ≤38, FMA scores at 30 and 90 days post-stroke were significantly higher in MEP + patients than in MEP- patients. Proportional recovery at 30 and 90 days post-stroke was significantly higher in MEP + patients than in MEP- patients. MEP + patients had a higher percentage of good functional outcomes than MEP- patients, without statistical difference. Among patients with initial FMA score >38, FMA scores were 60.4 ± 4.8 and 63.9 ± 2.9 and proportional recovery was 65.2 ± 27.0% and 83.7 ± 24.6% at 30 and 90 days post-stroke, respectively. CONCLUSIONS: Among patients with moderate-to-severe ischemic stroke, MEP + patients had better motor recoveries (approximately 70%) than MEP– patients at 90 days post-stroke. MEP + patients had better functional outcomes than MEP- patients.