The Changes of Motor Evoked Potential and Silent Period after Electrical Stimulation in Stroke Patients

ABSTRACT

OBEJCTIVE This study was proposed to evaluate the electrophysiologic changes in motor evoked potentials (MEPs) and silent period after paraspinal electrical stimulation near caudal area of the spinal cord in stroke patients. METHOD: Electrical stimulation was applied to T12 paraspinal area using interferential current therapy (80~100 Hz) in 18 stroke patients. The amplitude and latency of cortical motor evoked potential and duration of silent period were measured before and after the electrical stimulation. RESULTS: The amplitude of MEPs in affected side was low compared with unaffected side. The duration of silent period was variable in affected side. The duration of silent period was increased after the electrical stimulation in stroke patients (p<0.05). Changes of the amplitude and latency of MEPs were not significant. CONCLUSION: These results mean that the central inhibitory mechanism affecting the silent period is activated by a certain electrical stimulation near caudal area of the spinal cord in stroke patients.