PURPOSE: The integrity of the pyramidal tract (PT) does not seem to influence clinical improvement after two weeks of Constraint-Induced Movement Therapy (CIMT). However, when PT is intact, improvement is associated with a decrease of fMRI-activation in primary sensorimotor cortex (SMC) and when affected, with an increase of activation in SMC. The aim was to observe the long-term effect of CIMT, depending on the integrity of the PT, and to correlate improvement with changes in fMRI-activation. SUBJECTS AND METHODS: Twelve new chronic stroke patients were treated with CIMT and integrity of PT was measured with transcranial magnetic stimulation. Before therapy, after therapy, and after 6 months, changes in motor function were correlated with differential and percent fMRI signal changes. RESULTS: All patients improved after two weeks of therapy, but only those with intact PT maintained improvement after 6 months. When PT was intact, improvement correlated with first a decrease of activation in SMC and after 6 months with an increase. When PT was affected, improvement consistently correlated with an increase in a lateral extension of SMC. Percent changes of activation were surrounded by differential changes. CONCLUSIONS: An intact PT might be advantageous for lasting improvement after CIMT and subregions in the SMC seem to behave differently during recovery.
PURPOSE: The integrity of the pyramidal tract (PT) does not seem to influence clinical improvement after two weeks of Constraint-Induced Movement Therapy (CIMT). However, when PT is intact, improvement is associated with a decrease of fMRI-activation in primary sensorimotor cortex (SMC) and when affected, with an increase of activation in SMC. The aim was to observe the long-term effect of CIMT, depending on the integrity of the PT, and to correlate improvement with changes in fMRI-activation. SUBJECTS AND METHODS: Twelve new chronic strokepatients were treated with CIMT and integrity of PT was measured with transcranial magnetic stimulation. Before therapy, after therapy, and after 6 months, changes in motor function were correlated with differential and percent fMRI signal changes. RESULTS: All patients improved after two weeks of therapy, but only those with intact PT maintained improvement after 6 months. When PT was intact, improvement correlated with first a decrease of activation in SMC and after 6 months with an increase. When PT was affected, improvement consistently correlated with an increase in a lateral extension of SMC. Percent changes of activation were surrounded by differential changes. CONCLUSIONS: An intact PT might be advantageous for lasting improvement after CIMT and subregions in the SMC seem to behave differently during recovery.