Hemodynamic Response and Motor Functions Following Transcranial Direct Current Stimulation in Acute Stroke
Hemodynamic Response and Motor Functions Following Transcranial Direct Current Stimulation in Acute Stroke
The aim of the present study is to evaluate the possible effect of using dual-tDCS applied
 before conventional physical therapy on motor functions and hemodynamic response
It is generally accepted that transcranial direct current stimulation (tDCS) can induce
 change in cortical excitability and thus modulate brain plasticity in human brain. tDCS has
 been used in neurorehabilitation to benefit ischemic stroke patients at different stage of
 stroke especially subacute or chronic phase with positive and safety reports. While, in acute
 phase, there is few evidences regarding to the effect of tDCS.

 After unilateral stroke, the excitability of affected hemisphere is decreased, an increase in
 the excitability of unaffected hemisphere and an abnormally high interhemispheric inhibition
 (IHI) drive from intact to lesioned hemisphere have been demonstrated. Prevent the abnormal
 IHI and thus increase the excitability of the affected hemisphere in the early phase would be
 a beneficial for stroke rehabilitation.

 Based on the polarity-specific effects, anodal tDCS increases cortical excitability and
 cathodal tDCS decreases cortical excitability. Dual-tDCS is a technique applying two
 electrodes over both cerebral hemispheres at the same time) to i) restore excitability in the
 ipsilesional hemisphere: anode over the ipsilesional hemisphere ii) to down regulate
 excitability of the contralesional hemisphere and rebalance IHI.

 The mechanism underlying cortical excitability changes after tDCS is still elusive. However,
 one of possible mechanism indicating a change in cortical activity is the subsequent
 variation in hemodynamic response. Different methods have been developed for cerebral
 hemodynamic evaluations i.e. cerebral blood flow velocity (CBFV). Transcranial color-coded
 duplex ultrasonography (TCCD) has been used to measure CBFV through the major intracranial
 vessels through relatively thin bone windows. It is a non-invasive, relatively inexpensive,
 safe and portable allowing bedside monitoring of CBFV that is convenience in the intensive
 care setting.

 The aim of the present study is to investigate hemodynamic response and motor performance
 following dual-tDCS 5-sessions over the primary motor cortex (M1) since 5 consecutive days
 for tDCS appeared to be safe to use in acute stroke and has been shown to induce motor
 recovery in other phases of stroke The hypothesis of the present study is that dual-tDCS
 applied before conventional physical therapy, would induce better motor performance and
 induce changes in CBFV at immediate after of 5-sessions and at follow up at 1 month compared
 to sham.
Inclusion Criteria:

 1. Between 18 and 75 years of age

 2. First ever-acute ischemic unilateral stroke in the anterior circulation (ACA or MCA
 territory), MRI/CT scan result is thus required.

 3. Stroke onset from 2-10 days

 4. Good level of consciousness (alert)

 5. Free of any neurological antecedent, unstable condition that may increase the risk of
 stimulation such as epilepsy; although tDCS is believed to induce less or no risk of
 seizure and epileptic seizure have never been reported in tDCS study even in a study
 with active epilepsy (19).

 6. No significant carotid artery occlusive disease (< 50% internal carotid artery
 stenosis) as assessed by carotid duplex ultrasonography

 7. Presence of bilateral temporal acoustic window for optimal TCCD evaluation

 8. Modified Ranking Scale ≤ 4

 Exclusion Criteria:

 1. Recurrent stroke

 2. Having score more than 20 points on the National Institute of Health Stroke Scale

 3. Be unable to understand the instruction.

 4. Presence of intracranial metal implantation, cochlear implant, or cardiac pacemaker.

 5. Having as excessive pain in any joint of the lower limb (numerical pain rating score >
 7)

 6. Open wound or wound infraction on scalp