I would have never consented to this. I would have been unable to eat,dress, go to the bathroom(1 or 2), open any door. It is really only available for high functioning individuals.
Activation changes in sensorimotor cortex during improvement due to CIMT in chronic stroke
Restorative Neurology and Neuroscience 29 (2011) 299–310DOI 10.3233/RNN-2011-0600IOS Press
Michel Rijntjes
a
,
∗
, Farsin Hamzei
b
, Volkmar Glauche
a
, Dorothee Saur
c
and Cornelius Weiller
aa
Department of Neurology, University of Freiburg, Freiburg, Germany
b
Moritz-Clinic for Neurological Rehabilitation, Bad Klosterlausnitz, Germany
c
Department of Neurology, University of Leipzig, Leipzig, Germany
Abstract
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:
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:
Results:
All patients improved after two weeks of therapy, but only those with intact PT maintained improvement after 6months. 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:
Conclusions:
An intact PT might be advantageous for lasting improvement after CIMT and subregions in SMC seem to behave differently during recovery.
1. Introduction
Constraint-Induced Movement Therapy (CIMT) is effective in selected patients with chronic motor stroke(Taub and Uswatte, 2002; Rijntjes et al., 2005). Improvement, at least after two weeks of therapy, seems to be independent from the lesion site, even when structural MRI shows infarction in the posterior limb of the internal capsule(Gauthier,2009),where the pyramidal tract(PT) from the primary hand area passes through (Fries et al., 1993; Morecraft et al., 2002;Wenzelburger et al., 2005). However, while the integrity of the PT may not influence the benefit of CIMT when measured directly after therapy, it might still influence the sustainability of effects in the long term. Therefore, in a new cohort of chronic stroke patients, we allocated patients in two groups, according to the integrity of the PT, as measured with Transcranial Magnetic Stimulation (TMS), and looked at the long-term effect of CIMT. Related to this question is the possibly that improvement can be associated with different mechanisms of reorganization: the activation pattern in primary sensorimotor cortex (SMC) measured with fMRI depends strongly on the integrity of the PT (measured with TMS)(Hamzeietal.,2006,2008). If the primary motor cortex or its outflow via the PT was affected, patients showed a treatment-induced increase of activation in SMC after two weeks of CIMT. If the primary motor cortex and the PT were not affected, patients showed a decrease of activation in SMC. Although no direct correlation between fMRI signal change and clinical improvement was performed in these last two studies, both groups profited from CIMT when measured directly after therapy. To investigate the mechanisms behind treatment effects in the long term, we correlated fMRI signal changes with changes in motor score between the time points before and directly after two weeks of CIMT (1st phase), and between the timepointsdirectlyafterCIMTandafter6monthsoffollowup (2nd phase). However, there is no straight forward relation between changes in motor scores and BOLD-signal changes in fMRI. Motor scores are not continuous and are developed for inter-observer reliability,consistency over time or for comparisons between patients, not for comparison with brain activity.For motor scores, one approach is to use differential changes (score at time-point two minus score at time-point one) (Prabhakaran et al., 2008; Marshallet al., 2009). Another common approach is using ratioor percent changes, which can be related to baseline performance(e.g.Johansen-Bergetal.,2002),to maximum possible value (e.g. Malouin et al., 2004) or to the unaffected extremity (e.g. Ward et al., 2003). Vice versa, the same considerations apply to fMRI signal changes: BOLD-signal change is directly related to neuronal activity (Logothetis et al., 2001), but how much neuronal activity (and thereby BOLD-signal)should increase for a certain gain in performance in a clinical score is completely unclear.Applying nonparametric models may be one solution, but would limit statements about the actual distribution of changes. There is no simple solution and to further explore this question, we correlated per-cent changes in motor score with both differential and percent changes in BOLD-signal.As paradigm for fMRI we used passive movement of the hand, as it is independent from individual performance and improvements. Passive movement inducesalmost identical patterns of activation in SMC com-pared to active movements in healthy subjects and stroke patients, including the primary sensorimotor cortex (Weiller et al., 1996; Lee et al., 1998; Mimaet al., 1999), is reliable over time (Nelles et al., 1999;Loubinoux et al., 2001, 2003; Tombari et al., 2004;Ward et al., 2006) and has been used successfully in longitudinal studies on recovery from motor stroke(Loubinoux et al., 2003; Tombari et al., 2004; Wardet al., 2006; Hamzei et al., 2008). We chose the WMFT-sec score for comparison with fMRI-data because it is considered to measure clinically relevant improvements (Wolf et al., 2006), is reliable, internally consistent, stable (Morris et al.,2001; Wolf et al., 2005), and developed especially for monitoring also small increases in performance.It assesses a wide range of everyday hand movements,and it accurately measures performance with a stop-watch.c
1. Introduction
Constraint-Induced Movement Therapy (CIMT) is effective in selected patients with chronic motor stroke(Taub and Uswatte, 2002; Rijntjes et al., 2005). Improvement, at least after two weeks of therapy, seems to be independent from the lesion site, even when structural MRI shows infarction in the posterior limb of the internal capsule(Gauthier,2009),where the pyramidal tract(PT) from the primary hand area passes through (Fries et al., 1993; Morecraft et al., 2002;Wenzelburger et al., 2005). However, while the integrity of the PT may not influence the benefit of CIMT when measured directly after therapy, it might still influence the sustainability of effects in the long term. Therefore, in a new cohort of chronic stroke patients, we allocated patients in two groups, according to the integrity of the PT, as measured with Transcranial Magnetic Stimulation (TMS), and looked at the long-term effect of CIMT. Related to this question is the possibly that improvement can be associated with different mechanisms of reorganization: the activation pattern in primary sensorimotor cortex (SMC) measured with fMRI depends strongly on the integrity of the PT (measured with TMS)(Hamzeietal.,2006,2008). If the primary motor cortex or its outflow via the PT was affected, patients showed a treatment-induced increase of activation in SMC after two weeks of CIMT. If the primary motor cortex and the PT were not affected, patients showed a decrease of activation in SMC. Although no direct correlation between fMRI signal change and clinical improvement was performed in these last two studies, both groups profited from CIMT when measured directly after therapy. To investigate the mechanisms behind treatment effects in the long term, we correlated fMRI signal changes with changes in motor score between the time points before and directly after two weeks of CIMT (1st phase), and between the timepointsdirectlyafterCIMTandafter6monthsoffollowup (2nd phase). However, there is no straight forward relation between changes in motor scores and BOLD-signal changes in fMRI. Motor scores are not continuous and are developed for inter-observer reliability,consistency over time or for comparisons between patients, not for comparison with brain activity.For motor scores, one approach is to use differential changes (score at time-point two minus score at time-point one) (Prabhakaran et al., 2008; Marshallet al., 2009). Another common approach is using ratioor percent changes, which can be related to baseline performance(e.g.Johansen-Bergetal.,2002),to maximum possible value (e.g. Malouin et al., 2004) or to the unaffected extremity (e.g. Ward et al., 2003). Vice versa, the same considerations apply to fMRI signal changes: BOLD-signal change is directly related to neuronal activity (Logothetis et al., 2001), but how much neuronal activity (and thereby BOLD-signal)should increase for a certain gain in performance in a clinical score is completely unclear.Applying nonparametric models may be one solution, but would limit statements about the actual distribution of changes. There is no simple solution and to further explore this question, we correlated per-cent changes in motor score with both differential and percent changes in BOLD-signal.As paradigm for fMRI we used passive movement of the hand, as it is independent from individual performance and improvements. Passive movement inducesalmost identical patterns of activation in SMC com-pared to active movements in healthy subjects and stroke patients, including the primary sensorimotor cortex (Weiller et al., 1996; Lee et al., 1998; Mimaet al., 1999), is reliable over time (Nelles et al., 1999;Loubinoux et al., 2001, 2003; Tombari et al., 2004;Ward et al., 2006) and has been used successfully in longitudinal studies on recovery from motor stroke(Loubinoux et al., 2003; Tombari et al., 2004; Wardet al., 2006; Hamzei et al., 2008). We chose the WMFT-sec score for comparison with fMRI-data because it is considered to measure clinically relevant improvements (Wolf et al., 2006), is reliable, internally consistent, stable (Morris et al.,2001; Wolf et al., 2005), and developed especially for monitoring also small increases in performance.It assesses a wide range of everyday hand movements,and it accurately measures performance with a stop-watch.c
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