Can the site of brain lesion predict improved motor function after Low-TENS treatment on the post-stroke paretic arm?

Objectives: Previous reports suggest that afferent stimulation improves arm motor function in patients suffering from stroke. The aim of this pilot st udy was to test the hypothesis that the brain lesion location determines th e response to low-frequency (1.7 Hz) transcutaneous electric nerve stimulat ion (Low-TENS) therapy. Design: Magnetic resonance imaging (MRI) was performed on 14 patients who h ad previously received Low-TENS on the paretic arm after stroke. Methods: MR images were classified with two different methods. First, lesio ns in the cortical and the subcortical areas were registered. Secondly, any change in a described periventricular white matter (PVWM) area was recorde d. Interactions between the lesion site, as detected by MRI, and response t o Low-TENS treatment were analysed. Results: Arm motor function after Low-TENS treatment in relation to lesion in different brain areas showed that absence of lesions in the PVWM area in creased the possibility for improved motor capacity after afferent stimulat ion. Conclusions: The site of lesion may play a role in prognosis/outcome after Low-TENS treatment but this hypothesis should be further tested in a larger prospective study.