Long‐term white matter tract reorganization following prolonged febrile seizures

Abstract

SummaryObjectiveDiffusion magnetic resonance imaging (MRI) studies have demonstrated acute white matter changes following prolonged febrile seizures (PFS), but their longer‐term evolution is unknown. We investigated a population‐based cohort to determine white matter diffusion properties 8 years after PFS.MethodsWe used diffusion tensor imaging (DTI) and applied Tract‐Based Spatial Statistics for voxel‐wise comparison of white matter microstructure between 26 children with PFS and 27 age‐matched healthy controls. Age, gender, handedness, and hippocampal volumes were entered as covariates for voxel‐wise analysis.ResultsMean duration between the episode of PFS and follow‐up was 8.2 years (range 6.7–9.6). All children were neurologically normal, and had normal conventional neuroimaging. On voxel‐wise analysis, compared to controls, the PFS group had (1) increased fractional anisotropy in early maturing central white matter tracts, (2) increased mean and axial diffusivity in several peripheral white matter tracts and late‐maturing central white matter tracts, and (3) increased radial diffusivity in peripheral white matter tracts. None of the tracts had reduced fractional anisotropy or diffusivity indices in the PFS group.SignificanceIn this homogeneous, population‐based sample, we found increased fractional anisotropy in early maturing central white matter tracts and increased mean and axial diffusivity with/without increased radial diffusivity in several late‐maturing peripheral white matter tracts 8 years post‐PFS. We propose disruption in white matter maturation secondary to seizure‐induced axonal injury, with subsequent neuroplasticity and microstructural reorganization as a plausible explanation.

Febrile seizures: an overview

“… 1 , 99 , 101 , 102 Prolonged febrile seizures may also cause disruption in white matter maturation, with subsequent neuroplasticity and microstructural reorganization. 103 …”

Intelligence and memory outcomes within 10 years of childhood convulsive status epilepticus

“…Convulsive status epilepticus (CSE) is the most common neurological emergency in childhood [1] and is associated with a greater risk of pediatric mortality [2], structural brain abnormalities [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], and an overall poorer quality of life [15]. It is becoming increasingly evident that children with CSE, even those with no apparent neurological problems prior to CSE, show evidence of short-term structural and functional complications after CSE [4], [5], [8], [9], [10], [11], [14].…”

Long-term prognosis after childhood convulsive status epilepticus: a prospective cohort study

“…Data from our group and others suggest that CSE is associated with acute brain injury and short-term cognitive impairment, with at least partial recovery as a result of brain plasticity and reorganisation during follow-up. [3][4][5]32 We speculate that children with pre-existing brain pathology (structural or genetic) might have less reserve and thus less chance of recovery, which might explain the major contribution of cause to outcomes. Some evidence also suggests that repeated CSE are associated with worse outcomes.…”