Perinatal Stroke: Understanding Brain Reorganization
Condition: Stroke; Hemiparesis
MeSH terms: Stroke; Paresis
Study type: Observational

Summary: 
      The incidence of perinatal stroke is relatively common, as high as 1 in 2,300 births, but
      little is known about the resulting changes in the brain that eventually manifest as cerebral
      palsy (CP). Motor signs that indicate the infant is beginning to develop CP often do not
      become evident for several months after the diagnosis of perinatal stroke which delays
      therapy. The main purpose of this study is to examine early brain reorganization in infants
      3-12 months of age corrected for prematurity with perinatal stroke using magnetic resonance
      imaging (MRI) and non-invasive transcranial magnetic stimulation (TMS). In addition, the
      association between the brain reorganization and motor outcomes of these infant participants
      will be identified.

      In this study, the MRI scans will include diffusion tensor imaging (DTI) - an established
      method used to investigate the integrity of pathways in the brain that control limb movement.
      Infants will be scanned during nature sleeping after feeding. The real scanning time will be
      less than 38 minutes. TMS is a painless, non-surgical brain stimulation device which uses
      principles of electromagnetic induction to excite cortical tissue from outside the skull.
      Using TMS as a device to modulate and examine cortical excitability in children with
      hemiparetic CP and in adults has been conducted previously.

      In this infant study, we will assess cortical excitability from the motor cortex of both the
      ipsilesional and contralesional hemispheres under the guidance of a frameless stereotactic
      neuronavigation system. Additionally, the investigators will assess infants' movement quality
      using an age-appropriate standardized movement assessment. This will allow the investigators
      to examine the relationship between measures of motor pathway integrity and early signs of
      potential motor impairment. We will longitudinally follow enrolled infants, and complete
      repeat assessments at 12- and 24-months corrected age to assess how infants develop over time
      after perinatal stroke. The remote follow-up will occur at 5 years or less.
    

Detailed description: 
      Understanding the early brain reorganization before the brain has not yet largely reorganized
      is critical for developing efficacious early intervention. As a unique aspect of
      investigation, this study will combine Magnetic Resonance Imaging (MRI)/ Diffusion Tensor
      Imaging (DTI) and TMS to provide an additional opportunity to assess both the cortical
      excitability and corticospinal tract (CST) integrity in infants with perinatal stroke.

      Identifying the association between laboratory assessment results and developmental outcomes
      is also critical. This study is to use MRI/DTI and TMS to comprehensively examine both the
      CST integrity and cortical excitability in infants following perinatal stroke, and to
      identify association with motor outcome as evaluated by movement assessment.
    

Intervention name(s): Magnetic Resonance Imaging; Transcranial Magnetic Stimulation; General Movement Assessment
Intervention type(s): Device; Device; Behavioral
Intervention description(s): Anatomical and Diffusion Tensor Imaging Analysis.; Assessment of brain (cortical) excitability; Spontaneous movement assessment of infant while lying in unperturbed state.
Observational model: Other
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        The pilot study portion will recruit infants with unilateral perinatal stroke between 3 to
        5 months of corrected age to understand their brain reorganization after stroke.

        The follow-up study portion will recruit children aged 5 years or younger who have been
        diagnosed with perinatal stroke and who participated in the pilot study.
      
Keywords: perinatal stroke; transcranial magnetic stimulation; magnetic resonance imaging; diffusion tensor imaging; non-invasive brain stimulation; infant