Contralesional corticospinal tract integrity is predictive of motor function after stroke

Maybe the diagnosis need of damages is finally being recognized. From the 2011 Canadian Stroke Congress.
page 112 here:
http://www.strokecongress.org/2011/wp-content/uploads/2011/12/CSC_Abstracts.pdf
Background: Diffusion tensor imaging (DTI) can provide novel information about the integrity of white matter tracts after stroke. Reduced integrity of the corticospinal tract (CST) has been shown to be associated with moderate to severe motor dysfunction. It is unclear if this association also extends to well-recovered chronic
stroke individuals. Methods: We performed DTI-based quantification of CST integrity in well-recovered (upper extremity Fugl-Meyer (UE-FM) motor scale mean score: 55.33 ± 12.95) individuals (n=9) with chronic, first-time, right hemispheric, sub-cortical ischaemic lesions. Fractional anisotropy (FA) and interhemispheric FA asymmetry were used to quantify ipsi- and contralesional CST integrity. Motor function was indexed by: UE- FM, Wolf Motor Function Test (WMFT) asymmetry, Box and Blocks Test, and hand grip asymmetry. Correlational and linear regression analyses were conducted to evaluate the relationship between CST integrity and motor function.
Results: Contralesional FA was significantly correlated with each measure of motor function (range: r= -0.84-0.93, p<0.005). Higher contralesional FA values were predictive of higher UE-FM scores (r2=0.84, p=0.0003), lower WMFT asymmetry (r2=0.81, p=0.001), better non-hemiparetic arm Box and Blocks Test performance (r2=0.78, p=0.001) and less hand grip asymmetry (r2=0.66, p=0.005). Ipsilesional FA and FA asymmetry values were not associated with any measure of motor function. Conclusions: This is the first study demonstrating a significant association between contralesional white matter integrity and hemiparetic arm motor function in well-recovered individuals with chronic stroke. Previous work has demonstrated the importance of CST integrity in the affected hemisphere. Our findings suggest the integrity of the contralesional CST may also be an important neuroanatomical marker of motor function and recovery after stroke.