Evaluating fibre orientation dispersion in white matter: Comparison of diffusion MRI, histology and polarized light imaging.
Neuroimage
; 157: 561-574, 2017 08 15.
Article
en En
| MEDLINE
| ID: mdl-28602815
ABSTRACT
Diffusion MRI is an exquisitely sensitive probe of tissue microstructure, and is currently the only non-invasive measure of the brain's fibre architecture. As this technique becomes more sophisticated and microstructurally informative, there is increasing value in comparing diffusion MRI with microscopic imaging in the same tissue samples. This study compared estimates of fibre orientation dispersion in white matter derived from diffusion MRI to reference measures of dispersion obtained from polarized light imaging and histology. Three post-mortem brain specimens were scanned with diffusion MRI and analyzed with a two-compartment dispersion model. The specimens were then sectioned for microscopy, including polarized light imaging estimates of fibre orientation and histological quantitative estimates of myelin and astrocytes. Dispersion estimates were correlated on region - and voxel-wise levels in the corpus callosum, the centrum semiovale and the corticospinal tract. The region-wise analysis yielded correlation coefficients of r = 0.79 for the diffusion MRI and histology comparison, while r = 0.60 was reported for the comparison with polarized light imaging. In the corpus callosum, we observed a pattern of higher dispersion at the midline compared to its lateral aspects. This pattern was present in all modalities and the dispersion profiles from microscopy and diffusion MRI were highly correlated. The astrocytes appeared to have minor contribution to dispersion observed with diffusion MRI. These results demonstrate that fibre orientation dispersion estimates from diffusion MRI represents the tissue architecture well. Dispersion models might be improved by more faithfully incorporating an informed mapping based on microscopy data.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Bancos de Tejidos
/
Astrocitos
/
Técnicas Histológicas
/
Imagen de Difusión por Resonancia Magnética
/
Sustancia Blanca
/
Microscopía
/
Vaina de Mielina
Tipo de estudio:
Prognostic_studies
Límite:
Aged
/
Aged80
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Neuroimage
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2017
Tipo del documento:
Article