Anisotropy of transcallosal motor fibres indicates functional impairment in children with periventricular leukomalacia

Abstract

ABBREVIATIONS CST Corticospinal tract DTI Diffusion tensor imaging iSPIpsilateral silent period PVL Periventricular leukomalacia TCMF Transcallosal motor fibres TMS Transcranial magnetic stimulation AIM In children with bilateral spastic cerebral palsy (CP), periventricular leukomalacia (PVL) is commonly identified on magnetic resonance imaging. We characterized this white matter condition by examining callosal microstructure, interhemispheric inhibitory competence (IIC), and mirror movements.METHOD We examined seven children (age range 11y 9mo-17y 9mo, median age 15y 10mo, four females, three males) with bilateral spastic CP ⁄ PVL (Gross Motor Function Classification System level I or II, Manual Ability Classification System level I) and 12 age-matched controls (age range 11y 7mo-17y 1mo, median age 15y 6mo, seven females, five males). Fractional anisotropy of the transcallosal motor fibres (TCMF) and the corticospinal tract (CST) of both sides were calculated. The parameters of IIC (transcranial magnetic stimulation) and mirror movements were measured using a standardized clinical examination and a computer-based hand motor test. Periventricular leukomalacia (PVL) is caused by a hypoxicischemic event resulting in encephalopathy in the developing brain, predominantly between 24 and 34 weeks' gestation. RESULTS

The Role of Diffusion-Tensor Magnetic Resonance Imaging and Tractography in the Diagnosis of Structural Brain Disorders in Children with Cerebral Palsy

“…Отмечено также, что с тяжестью двигательных нарушений при ДЦП сопостави-мо снижение фракционной анизотропии кортикоспиналь-ных трактов на уровне варолиева моста [54]. Некоторые авторы предполагают, что более точным индикатором моторного дефицита у детей с диплегической формой ДЦП является снижение фракционной анизотропии воло-кон мозолистого тела, а не кортикоспинальных трактов, особенно в отношении тонких мануальных навыков и точ-ности выполнения дифференцированных движений [55]. В исследовании А. М. Мамедьярова и соавт.…”

Motor, sensory and executive function brain networks in children with unilateral cerebral palsy

“…Only one study used high angular resolution diffusion imaging with a higher-order diffusion model 48 . Thirteen studies (59%) used tractography 48,[64][65][66][67][68][69][70][71][72] and one study (5%) used tract-based spatial statistics 73 to probe the integrity of white matter pathways. Three studies (14%) used 3T MRI scanners 48,73 , whereas the remainder (86%) used 1.5T MRI scanners.…”

“…Of the 20 studies (91%) that used ROI placement, 17 (77%) used manual placement, whereas three (14%) used automatic parcellation 48,74,75 . Only six (35%) of the studies using manual ROI placement included reliability analysis 65,66,71,[76][77][78] .…”

“…There were on average 1.6 males to each female. Four studies (18%) included participants with spasticity in any motor distribution 67,72,75,80 ; 14 studies (64%) investigated specific motor distributions of spasticity, including seven (32%) of children with spastic hemiplegia 48,64,65,[68][69][70]81 ; two studies (9%) of children with spastic diplegia 66,73 ; three studies (14%) of children with spastic quadriplegia 60,71,82 , one study of children with bilateral spasticity 77 ; and one study comparing spastic quadriplegia with diplegia 79 .…”

“…Twelve studies (55%) assessed correlations between imaging and clinical outcomes 48, 61, 64-66, 69, 71-73, 77, 81, 82 . Of these, six (50%) assessed GMFCS 65, 71-73, 77, 82 , three (25%) used other clinical measures of global function 64,69,82 , and five (42%) assessed upper limb function 48,61,65,66,81 .…”