Reduced Field of View Diffusion Tensor Imaging and Fiber Tractography of the Pediatric Cervical and Thoracic Spinal Cord Injury

Abstract

The aim of this study is to assess the utility and effectiveness of diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) of the entire pediatric cervical and thoracic spinal cord toward discrimination of typically developing (TD) controls and subjects with spinal cord injury (SCI). A total of 43 pediatric subjects, including 23 TD subjects ranging in age from 6 to 16 years old and 20 subjects with SCI ranging in age from 7 to 16 years, were recruited and scanned using a 3.0 Tesla magnetic resonance scanner. Reduced field of view diffusion tensor images were acquired axially to cover the entire spinal cord across two slabs. For DTI analysis, motion correction was performed by coregistration of the diffusion-weighted images to the reference image (b0). Streamline deterministic tractography results were generated from the preprocessed data. DTI and DTT parameters of the whole cord, including fractional anisotropy (FA), mean diffusivity (MD), tract length, and tract density, were calculated, averaged across the whole spinal cord, and compared between the TD and SCI groups. Statistically significant decreases have been shown in FA (TD = 0.46 ± 0.11; SCI = 0.37 ± 0.09; p < 0.0001) and tract density (TD = 405.93 ± 243.84; SCI = 268.90 ± 270.34; p < 0.0001). However, the mean length of tracts and MD did not show significant differences. When investigating differences in DTI and DTT parameters above and below the injury site, it was shown that the FA and tract density in patients with cervical SCI decreased significantly in the thoracic region. An identical trend was observed in the cervical region for patients with thoracic SCI as well. When comparing TD and SCI subjects, FA and tract density were the most sensitive parameters in detecting functional changes of the spinal cord in chronic pediatric SCI. The results show that both DTI and DTT have the potential to be imaging biomarkers in the diagnosis of SCI.

Diffusion Tensor Imaging in Diagnosis of Post-Traumatic Syringomyelia in Spinal Cord Injury in Rats

“…Thus, we proposed the hypothesis that the combinative application of conventional MRI, DTI, and DTT be effective in evaluation of SCI and PTS. This hypothesis concurs with the latest published clinical reports [ 19 – 21 ].…”

“…DTT can visualize the injury epicenter and the interrupted spinal cord tracts. DTI is a useful quantitative evaluation for nerve degeneration and axonal loss, as changes in axonal structure can affect the diffusion of water molecules [ 15 , 16 ]. A series of studies have concluded that FA values decrease and ACD values increase at lesion sites after SCI [ 17 , 18 ].…”

Hemispheric Regional Based Analysis of Diffusion Tensor Imaging and Diffusion Tensor Tractography in Patients with Temporal Lobe Epilepsy and Correlation with Patient outcomes

“…The fiber tracts of the brain were generated using a deterministic streamline approach. This method has proven to be an effective algorithm capable of estimating the trajectories of white matter tracts in the brain and the cord 26–28 . However, deterministic fiber tracking has limitations, particularly in voxels where fibers are crossing, bending or kissing.…”

Effect of distortion corrections on the tractography quality in spinal cord diffusion‐weighted imaging

“…DWI stitching is difficult to perform and is sensitive to artifacts produced by respiratory and cardiac movements at the thoracic level of the spinal cord 9,57 . Nonetheless, several teams 14,58,59 have aimed to perform DWI and tractography of the entire spinal cord. Regardless of the MRI manufacturer, the field of view is not large enough to cover the entire spinal cord.…”