Additional file 1 of Diffusion tensor imaging in anisotropic tissues: application of reduced gradient vector schemes in peripheral nerves
Creators: name: Foesleitner, Olivia
name: Sulaj, Alba
name: Sturm, Volker
name: Kronlage, Moritz
name: Preisner, Fabian
name: Kender, Zoltan
name: Bendszus, Martin
name: Szendroedi, Julia
name: Heiland, Sabine
name: Schwarz, Daniel
Publisher: name: figshare
Year: 2024
Subjects: subject: Space Science
subject: Medicine
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Mental Health
subject: Computational Biology

description: Additional file 1: Suppl. Table 1. Values of fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (AD), and radial diffusivity (RD). Values are median (IQR). ADC [mm2/s], AD [10–3 mm2/s], RD [10–3 mm2/s]. Suppl. Table 2. Standard deviation (SD) of fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (AD), and radial diffusivity (RD) values. Values are median (min-max). Suppl. Table 3. Values of nerve angulation and intraneurial connective tissue across regions. Values are median (min-max). Suppl. Table 4a. Correlation analysis of absolute fractional anisotropy values and intraneurial connective tissue. p values &lt; .05 are marked in bold letters. r, Spearman's correlation coefficient. Suppl. Table 5a. Correlation analysis of absolute fractional anisotropy values and nerve angulation. p values &lt; .05 are marked in bold letters. r, Spearman's correlation coefficient. Suppl. Table 4b. Correlation analysis of accuracy of fractional anisotropy values and intraneurial connective tissue. p values &lt; .05 are marked in bold letters. r, Spearman's correlation coefficient. Suppl. Table 5b. Correlation analysis of accuracy of fractional anisotropy values and nerve angulation. p values &lt;. 05 are marked in bold letters. r, Spearman's correlation coefficient. Supplementary Figure 1. Accuracy of FA as assessed by Bland-Altman plots. Bland-Altman plots showing the limits of difference (± 2 SD) in healthy subjects (upper panel), diabetic patients (middle panel) and age-matched controls (lower panel) between paired values of fractional anisotropy (FA) calculated with 20-vector DTI and model 1 (A, D, G), model 2 (B, E, H), or model 3 (C, F, I) in the tibial nerve at thigh level. Supplementary Figure 2. Accuracy of ADC as assessed by Bland-Altman plots. Bland-Altman plots showing the limits of difference (± 2 SD) in healthy subjects (upper panel), diabetic patients (middle panel) and age-matched controls (lower panel) between paired values of apparent diffusion coefficient (ADC) calculated with 20-vector DTI and model 1 (A, D, G), model 2 (B, E, H), or model 3 (C, F, I) in the tibial nerve at thigh level. Supplementary Figure 3. Accuracy of different AD and RD calculation models. Forest plots of absolute axial diffusivity (AD, left side) and radial diffusivity (right side) show the accuracy of models 1-3 compared to the 20-directional standard model (DTI20). Symbols indicate the median, horizontal lines depict the range, and gray boxes show the interquartile range. Supplementary Figure 4. Precision of different AD and RD calculation models. Forest plots of within-subject precision of axial diffusivity (AD, left side) and radial diffusivity (RD, right side) show the precision of models 1-3 compared to the 20-directional standard model (DTI20). Standard deviation is plotted on the x-axes. Symbols indicate the median, horizontal lines depict the range, and gray boxes show the interquartile range. Significant differences between models 1-3 to DTI20 are indicated with asterisks (* p &lt; .05; ** p &lt; .01, ** p &lt; .001). Supplementary Figure 5. Group differences based on different ADC, AD and RD calculation models. Box-and-whisker plots of apparent diffusion coefficient (ADC) and axial and radial diffusivity (AD, RD) measured in the tibial nerve at the distal thigh show group differences between diabetic patients and healthy subjects using the four analyzed models. Data are medians (lines in boxes), 25th to 75th percentiles (bottom and top of boxes), and ranges (Tukey whiskers). Supplementary Figure 6. FA dependence on intraneurial connective tissue and nerve angulation. Scatter plot of fractional anisotropy (FA) measured in the tibial nerve at the distal thigh in young healthy subjects in relation to percentage of intraneurial connective tissue shows a negative correlation in all four examined models (A), while no clear dependence was detected between FA accuracy and nerve angulation (B).