Reliability of the corticospinal tract and arcuate fasciculus reconstructed with DTI-based tractography: implications for clinical practice

To assess the reliability of diffusion tensor imaging (DTI)-based fibre tractography (FT), which is a prerequisite for clinical applications of this technique. Here we assess the test-retest reproducibility of the architectural and microstructural features of two clinically relevant tracts reconstructed with DTI-FT. The corticospinal tract (CST), arcuate fasciculus (AF) and its long segment (AFl) were reconstructed in 17 healthy subjects imaged twice using a deterministic approach. Coefficients of variation (CVs) of diffusion-derived tract values were used to assess the microstructural reproducibility. Spatial correlation and fibre overlap were used to assess the architectural reproducibility. Spatial correlation was 68 % for the CST and AF, and 69 % for the AFl. Overlap was 69 % for the CST, 61 % for the AF, and 59 % for the AFl. This was comparable to 2-mm tract shift variability. CVs of diffusion-derived tract values were at most 3.4 %. The results showed low architectural and microstructural variability for the reconstruction of the tracts. The architectural reproducibility results encourage the further investigation of the use of DTI-FT for neurosurgical planning. The high microstructural reproducibility results are promising for using DTI-FT in neurology to assess or predict functional recovery. aEuro cent Magnetic resonance diffusion tensor fibre tractography is increasingly used in the neurosciences. aEuro cent The architectural reproducibility of fibre pathways can be up to 69 %. aEuro cent However the microstructural variability of fibre pathways is only 3.4 % at most. aEuro cent The architectural reproducibility results encourage the use of DTI-FT for neurosurgery. aEuro cent The microstructural reproducibility results support the use of DTI-FT in neurology.