Neuropediatrics 2006; 37 - MP28
DOI: 10.1055/s-2006-943625

REDUCED INTRACORTICAL INHIBITION OF THE CORTICAL REPRESENTATION OF THE PARETIC HAND AFTER PRE- OR PERINATAL STROKE

V Brodbeck 1, M Walther 1, N Wagner 1, M Staudt 1, V Mall 1, S Berweck 1
  • 1Dept. of Pediatric Neurology and Developmental Medicine, Dr. von Hauners' Children's Hospital, University of Munich, Munich, Germany

Objectives: To measure intracortical inhibition and facilitation in a homogeneous group of patients with unilateral pre- or perinatal stroke.

Methods: Using transcranial magnetic stimulation (TMS) over both hemispheres, we measured motor threshold (MT) and intracortical inhibition (ICI) and facilitation (ICF) with interstimulus intervals (ISI) of 2–20ms in 11 patients (mean age 15.7 years) with unilateral hemiparesis due to cortico-subcortical pre- or perinatal stroke. Patients were included only when contralateral tracts to the paretic hand were detectable.

Results: We found significantly reduced ICI, displayed by facilitation of relative MEP amplitudes at ISI of 2 to 5 ms over the affected compared to the contralesional hemisphere (p>0.05). Individual MT over the affected hemisphere were significantly higher compared to the contralesional hemisphere, (mean 71% vs. 53%). Four patients showed additional ipsilateral tracts to the paretic hand.

Conclusion: Our result of reduced ICI over the affected hemisphere in patients after congenital stroke is surprisingly similar to results found in patients late after adulthood stroke. Mechanisms of neuroplasticity available after congenital stroke might not be as differential to those available after adulthood stroke as has been assumed so far.