Kinetic DTI of the cervical spine: diffusivity changes in healthy subjects
Résumé
Introduction The study aims to assess the influence of neck
extension on water diffusivity within the cervical spinal cord.
Methods IRB approved the study in 22 healthy volunteers.
All subjects underwent anatomical MR and diffusion tensor
imaging (DTI) at 1.5 T. The cervical cord was imaged in
neutral (standard) position and extension. Segmental vertebral
rotations were analyzed on sagittal T2-weighted images using
the SpineView® software. Spinal cord diffusivity was measured in cross-sectional regions of interests at multiple levels
(C1–C5).
Results As a result of non-adapted coil geometry for spinal
extension, 10 subjects had to be excluded. Image quality of the
remaining 12 subjects was good without any deteriorating
artifacts. Quantitative measurements of vertebral rotation
angles and diffusion parameters showed good intra-rater reliability (ICC= 0.84–0.99). DTI during neck extension revealed
significantly decreased fractional anisotropy (FA) and increased radial diffusivity (RD) at the C3 level and increased
apparent diffusion coefficients (ADC) at the C3 and C4 levels
(p < 0.01 Bonferroni corrected). The C3/C4 level
corresponded to the maximal absolute change in segmental
vertebral rotation between the two positions. The increase in
RD correlated positively with the degree of global extension,
i.e., the summed vertebral rotation angle between C1 and C5
(R= 0.77, p= 0.006).
Conclusion Our preliminary results suggest that DTI can
quantify changes in water diffusivity during cervical spine
extension. The maximal differences in segmental vertebral
rotation corresponded to the levels with significant changes
in diffusivity (C3/C4). Consequently, kinetic DTI measurements may open new perspectives in the assessment of neural
tissue under biomechanical constraints
Origine : Fichiers produits par l'(les) auteur(s)
Loading...