Association of activity changes in the primary sensory cortex with successful motor rehabilitation of the hand following stroke.

BACKGROUND: Previous studies demonstrated a posterior shift of activation toward the primary sensory cortex (S1) following stroke; however, any relationship between this posterior shift and clinical outcome measures for the affected hand function were unclear. OBJECTIVE: The authors investigated the possible role of S1 in motor recovery. METHODS: Assuming that previous studies examined inhomogeneous groups of patients, the authors selected participants with chronic stroke who had moderate hand paresis, normal sensory examination and somatosensory-evoked potentials, and no lesion within the S1, thalamus, or brain stem. Constraint-induced movement therapy (CIMT) was used to train the impaired hand. To relate fMRI (functional MRI) activation changes from baseline to post-CIMT, a correlation analysis was performed with changes of the Wolf Motor Function Test (WMFT) as a test for the hand function. RESULTS: A close relationship was found between increases in hand function and peak changes in activation within the ipsilesional S1. With a better outcome, greater increases in activation within the S1 were evident (P < .03; r = 0.73). CONCLUSION: In selected patients, the sensory network influences training-induced motor gains. This predictive knowledge of plasticity when applying CIMT may suggest strategies to enhance the effect of therapy, such as the addition of electrical stimulation to enhance S1 excitability.

Long-term mortality and risk of stroke after transient ischemic attack: a hospital-based cohort study.

BACKGROUND: Stroke and mortality rates in patients with transient ischemic attack (TIA) differ widely between community-based studies and research cohorts. Our aim therefore was to provide a reliable estimate for TIA patients treated in German neurology departments with an acute stroke unit. METHODS: A total of 1951 consecutively admitted TIA patients were prospectively documented in 13 centers and 1480 (75.9%) gave consent for long-term follow-up. During a mean follow-up of 23.4 months, we assessed recurrent cerebrovascular events and cause of death in 1448 patients via standardized telephone interview including confirmation of endpoint events by the treating physician. RESULTS: Overall 94 patients (6.5%) suffered a stroke and 118 patients (8.1%) died, 21 due to stroke. The Kaplan-Meier estimate for stroke during the first year was 4.4% (95% CI 3.2-5.6%) which corresponds to a relative risk of 9.5 (95% CI 7.4-12.3) compared to the population-based stroke incidence in Germany. The annual rates after the first year were 2.2% (95% CI 1.7-2.7%) for stroke and 3.2% (95% CI 2.7-3.8%) for death. Independent predictors for stroke during follow-up were age and previous cerebrovascular events. The ABCD(2) score did not provide any meaningful prediction of stroke risk at 90 days. CONCLUSION: While the in-hospital risk of stroke was low, long-term stroke rates in our well-defined multicenter hospital-based cohort were comparable to a large randomized trial. In patients with a well-established diagnosis of TIA, only age and previous cerebrovascular events seem to constitute independent predictors for stroke during long-term follow-up.