RT Journal Article
SR Electronic
T1 Neurite Orientation Dispersion and Density Imaging for Assessing Acute Inflammation and Lesion Evolution in MS
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
DO 10.3174/ajnr.A6862
A1 S. Sacco
A1 E. Caverzasi
A1 N. Papinutto
A1 C. Cordano
A1 A. Bischof
A1 T. Gundel
A1 S. Cheng
A1 C. Asteggiano
A1 G. Kirkish
A1 J. Mallot
A1 W.A. Stern
A1 S. Bastianello
A1 R.M. Bove
A1 J.M. Gelfand
A1 D.S. Goodin
A1 A.J. Green
A1 E. Waubant
A1 M.R. Wilson
A1 S.S. Zamvil
A1 B.A. Cree
A1 S.L. Hauser
A1 R.G. Henry,
A1 University of California, San Francisco MS-EPIC Team
YR 2020
UL http://www.ajnr.org/content/early/2020/11/12/ajnr.A6862.abstract
AB BACKGROUND AND PURPOSE: MR imaging is essential for MS diagnosis and management, yet it has limitations in assessing axonal damage and remyelination. Gadolinium-based contrast agents add value by pinpointing acute inflammation and blood-brain barrier leakage, but with drawbacks in safety and cost. Neurite orientation dispersion and density imaging (NODDI) assesses microstructural features of neurites contributing to diffusion imaging signals. This approach may resolve the components of MS pathology, overcoming conventional MR imaging limitations.MATERIALS AND METHODS: Twenty-one subjects with MS underwent serial enhanced MRIs (12.6 ± 9 months apart) including NODDI, whose key metrics are the neurite density and orientation dispersion index. Twenty-one age- and sex-matched healthy controls underwent unenhanced MR imaging with the same protocol. Fifty-eight gadolinium-enhancing and non-gadolinium-enhancing lesions were semiautomatically segmented at baseline and follow-up. Normal-appearing WM masks were generated by subtracting lesions and dirty-appearing WM from the whole WM.RESULTS: The orientation dispersion index was higher in gadolinium-enhancing compared with non-gadolinium-enhancing lesions; logistic regression indicated discrimination, with an area under the curve of 0.73. At follow-up, in the 58 previously enhancing lesions, we identified 2 subgroups based on the neurite density index change across time: Type 1 lesions showed increased neurite density values, whereas type 2 lesions showed decreased values. Type 1 lesions showed greater reduction in size with time compared with type 2 lesions.CONCLUSIONS: NODDI is a promising tool with the potential to detect acute MS inflammation. The observed heterogeneity among lesions may correspond to gradients in severity and clinical recovery after the acute phase.ADaxial diffusivityDAWMdirty-appearing white matterFAfractional anisotropyFUfollow-upGELgadolinium-enhancing lesionHChealthy controlMDmean diffusivityNAWMnormal-appearing white matterNDIneurite density indexNGELnon-gadolinium-enhancing lesionNODDIneurite orientation dispersion and density ImagingnODInormalized orientation dispersion indexODIorientation dispersion indexRDradial diffusivityVECextra-neurite compartment