Journal: Brain Structure & Function

Article Title: Mapping myelin in white matter with T1-weighted/T2-weighted maps: discrepancy with histology and other myelin MRI measures

doi: 10.1007/s00429-022-02600-z

Figure Lengend Snippet: Histology and ROI sampling. Left, top: one of the four post-mortem brain samples with the corpus callosum in situ. Left, bottom: template of the corpus callosum showing 92 circular regions of interest (ROIs) based on the anatomical subdivision proposed by Witelson . Values were calculated inside the circular ROIs in the centre of each of the 92 squares of the callosal template and then extended to the square surrounding the circle. Centre: Luxol Fast Blue (LFB)-stained midsagittal sections (25 µm thick) of the corpora callosa of subjects 1, 2 and 3. Right: ROI-based, colour-coded maps of the myelin distribution of subjects 1, 2 and 3 along the midsagittal section of the corpus callosum assessed ex vivo via histological myelin staining. The histological myelin distribution pattern of the corpus callosum is different from the T1w/T2w pattern. All three LFB callosal samples have low myelin density in the anterior part (mainly rostrum/genu) and higher myelin density in the posterior part (mainly isthmus/splenium). Colour scale: purple, low values; red, high values

Article Snippet: We estimated myelin density using an LFB Optical Density analysis approach (Beckmann et al. ) with the Nikon NIS-Elements Advanced Research 4.12 software.

Techniques: Sampling, In Situ, Staining, Ex Vivo

Journal: Brain Structure & Function

Article Title: Mapping myelin in white matter with T1-weighted/T2-weighted maps: discrepancy with histology and other myelin MRI measures

doi: 10.1007/s00429-022-02600-z

Figure Lengend Snippet: To quantitatively evaluate the correlation between T1w/T2w, MWF and histology, MRI maps were sampled using the same 92-ROI sampling scheme used for histology and correlated with the corresponding average LFB-OD values. Data is displayed on arbitrary units (from 1 to 7) for all methods. A T1w/T2w does not positively correlate with the LFB-Optical Density analysis but, instead, has a significant negative correlation ( r 2 = 0.21 p < 0.001). B MWF presents a strong and significant positive correlation with LFB ( r 2 = 0.52, p < 0.001), suggesting a good agreement between the two modalities. C T1w/T2w and MWF maps do not correlate positively, as they are characterised by a weak negative correlation ( r 2 = 0.13, p < 0.001)

Article Snippet: We estimated myelin density using an LFB Optical Density analysis approach (Beckmann et al. ) with the Nikon NIS-Elements Advanced Research 4.12 software.

Techniques: Sampling