Facilitation of Motor Evoked Potentials by Voluntary Muscle Contraction in Post-stroke Patients. |
Kim, Ji Young , Lim, Jae Young , Kim, Wan Ho , Kim, Byung Sik , Han, Tai Ryoon |
1Department of Rehabilitation Medicine, National Rehabilitation Hospital, Korea. 2Department of Rehabilitation Medicine, Seoul National University College of Medicine, Korea. drlim1@snu.ac.kr |
뇌졸중 환자에서 수의적 수축에 의한 운동유발전위의 촉진 |
김지영, 임재영1, 김완호, 김병식, 한태륜1 |
국립재활병원 재활의학과, 1서울대학교 의과대학 재활의학교실 |
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Abstract |
Objective To identify interhemispheric differences of facilitation of motor evoked potentials (MEPs) from the affected and unaffected hemispheres after stroke and to correlate the differences with their motor functions. Method MEPs induced by cortical stimulation were obtained at both thenar muscles in 28 post-stroke patients. Motor cortex was stimulated with 110% and 130% intensity of threshold during rest, minimal and moderate voluntary muscle contraction. We analyzed the MEP amplitude or area in 130% threshold intensity at rest (Rmax) and on moderate contraction (Fmax). The ratio of Fmax in both hemispheres (interhemispheric facilitation ratio, FR) and the ratio of Fmax to Rmax (facilitation index, FI) were also analyzed. Pinch strength, Brunnstrom stage, and Jebsen hand function test were included evaluating their motor functions.
Results MEPs could not be evoked in cases whose Brunnstrom stage of hand was under 3. In response group, amplitude and area of Fmax of unaffected side were significantly larger than those of affected side (p<0.05). FR showed good correlation with clinical findings evaluating motor functions (p<0.05). In cases of FR > 0.5, FI of unaffected side was significantly greater than that of affected side (p<0.05).
Conclusion We suggest to use FR and FI as useful parameters for evaluation of hand function in post-stroke patients. (J Korean Acad Rehab Med 2003; 27: 314-319)
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Key Words:
Motor evoked potential, Stroke, Facilitation |
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