Article

Chiari type I malformation (C1M) may be symptomatic or asymptomatic as an
incidental finding. In this retrospective study, we applied diffusion tensor
imaging (DTI) to study the brainstem and cerebellar white matter tracts in C1M.
METHOD: Diffusion tensor imaging (DTI) data were acquired on a 1.5T MR-scanner
using balanced pairs of diffusion gradients along 20 non-collinear directions.
Measurements from regions of interest in each pontine corticospinal tract, medial
leminscus, and middle cerebellar peduncle (MCP) and in the lower brainstem were
obtained for fractional anisotropy and mean, axial, and radial diffusivity.
Values in symptomatic and asymptomatic children, and children with and without
hydromyelia were compared using analysis of variance. RESULTS: Fifteen children
with C1M (10 males, five females; six symptomatic [four with hydromyelia] and
nine asymptomatic) were included. Median age was 6 years 5 months (range 2y
10mo-15y 4mo). No significant differences in DTI scalars were found in the lower
brainstem. In both MCPs, axial diffusivity values were lower in symptomatic than
in asymptomatic children (p=0.049 and p=0.035 respectively) and higher in
children with hydromyelia versus without hydromyelia (p=0.018 and p=0.006
respectively). In the left MCP, mean diffusivity values were lower in symptomatic
than in asymptomatic children (p=0.047). INTERPRETATION: Our results show that
microstructural tissue alterations may be present in C1M. Additionally, our study
suggests a specific role for the MCPs in C1M. Further large-scale studies are
warranted.
CI - (c) 2014 Mac Keith Press.

Langue : ANGLAIS