Reorganization in congenital hemiparesis acquired at different gestational ages

Abstract

It is well established that the reorganizational potential of the developing human brain is superior to that of the adult brain, but whether age-dependent differences exist already in the prenatal and perinatal period is not known. We have studied sensorimotor reorganization in 34 patients with congenital hemiparesis (age range, 5-27 years), using transcranial magnetic stimulation and functional magnetic resonance imaging during simple hand movements. Underlying pathologies were brain malformations (first and second trimester lesions; n = 10), periventricular brain lesions (early third trimester lesions; n = 12), and middle cerebral artery infarctions (late third trimester lesions; n = 12). Of this cohort, eight patients with malformations and all patients with periventricular lesions have been published previously. In all three groups of pathologies, transcranial magnetic stimulation identified patients in whom the paretic hand was controlled via ipsilateral corticospinal projections from the contralesional hemisphere (n = 16). In these patients, the motor dysfunction of the paretic hand correlated significantly with the timing period of the underlying brain lesion. This demonstrates that the efficacy of reorganization with ipsilateral corticospinal tracts indeed decreases during pregnancy.

Relation between neuroradiological findings and upper limb function in hemiplegic cerebral palsy

“…Better upper limb function among hemiplegic children with periventricular lesions was also reported by others. [7][8][9] However, in these studies the evaluation of hand function was limited to a simple grading of the severity using 3-to 4-point ordinal scales. Results in our study additionally showed that children in the PVL-group had more grip strength and a tendency for lower muscle tone compared to children in the ACQ-group.…”

“…In congenital hemiplegia, due to pre-or perinatal brain damage, three main lesion types determined by the stage of brain development at the time of the insult have been described: malformations, periventricular lesions and cortical-subcortical lesions. [3][4][5][6][7] The fourth lesion type comprises all types of brain injuries acquired postnatally. 8 Previous attempts have been made to relate the classified lesions to the severity of neurological impairment.…”

“…8 Previous attempts have been made to relate the classified lesions to the severity of neurological impairment. [7][8][9][10][11] While some suggest that cortical-subcortical lesions result in a more severe hemiparesis or impaired upper limb function compared to periventricular lesions, [7][8][9] others could not demonstrate a relation between the different lesions types and upper limb function. 10,11 All studies included children with congenital hemiplegia and one study also included children with a postnatally acquired hemiplegia.…”

Motor imagery ability in children with congenital hemiplegia: Effect of lesion side and functional level

“…Such a result may not be surprising if we consider that motor processes may be less lateralized in children with congenital hemiplegia as a consequence of cortical reorganisation. Reorganisation can result in cortical projections to the hemiplegic hand being ipsilateral or mixed, as opposed to contralateral (Carr, Harrison, Evans, & Stephens, 1993;Staudt, et al, 2004). Little is known about how such reorganisation affects other motor processes in the brain, but we do know that when projections reorganize to the ipsilateral side, the afferent projections do not necessarily reorganize in the same pattern (Thickbroom, Byrnes, Archer, Nagarajan, & Mastaglia, 2001).…”

Transcranial magnetic stimulation in children

“…Unfortunately, this is by no means universal and, at times, the outcome can be devastating (Johnston) There are many factors which may determine this variability of outcomes, including the type, the extent, and the timing of the process that caused the original lesion (Staudt et al, 2004) One of the more common disorders which arise from perinatal insults is cerebral palsy. Cerebral palsy is a group of disorders characterized by injuries to the developing brain which affect the motor system; other areas of the brain may also be affected (Bax et al, 2005).…”