Analysis of radiological parameters associated with decreased fractional anisotropy values on diffusion tensor imaging in patients with lumbar spinal stenosis
Previous studies have indicated that decreased fractional anisotropy (FA) values on diffusion tensor imaging (DTI) are well correlated with the symptoms of nerve root compression. The aim of our study is to determine primary radiological parameters associated with decreased FA values in patients with lumbar spinal stenosis involving single L5 nerve root.
Patients confirmed with single L5 nerve root compression by transforaminal nerve root blocks were included in this study. FA values of L5 nerve roots on both symptomatic and asymptomatic side were obtained. Conventional radiological parameters, such as disc height, degenerative scoliosis, dural sac cross-sectional area (DSCSA), foraminal height (FH), hypertrophic facet joint degeneration (HFJD), sagittal rotation (SR), sedimentation sign, sagittal translation and traction spur were measured. Correlation and regression analyses were performed between the radiological parameters and FA values of the symptomatic L5 nerve roots. A predictive regression equation was established.
Twenty-one patients were included in this study. FA values were significantly lower at the symptomatic side comparing to the asymptomatic side (0.263 ± 0.069 vs. 0.334 ± 0.080, P = 0.038). DSCSA, FH, HFJD, and SR were significantly correlated with the decreased FA values, with r = 0.518, 0.443, 0.472 and − 0.910, respectively (P < 0.05). DSCSA and SR were found to be the primary radiological parameters related to the decreased FA values, and the regression equation is FA = − 0.012 × SR + 0.002 × DSCSA.
DSCSA and SR were primary contributors to decreased FA values in LSS patients involving single L5 nerve root, indicating that central canal decompression and segmental stability should be the first considerations in preoperative planning of these patients.
KeywordsDiffusion tensor imaging Fractional anisotropy Nerve roots Lumbar spinal stenosis Radiological parameters
We gratefully thank all the participants in this research study together with our technicians for their dedicated efforts in scanning standardization and quality assurance. This work was supported by Shanghai Municipal Science and Technology Commission (Grant number: 16411964100, 2016) and the National Natural Science Foundation of China (Grant no. 81472036, 2015).
Compliance with ethical standards
Conflict of interest
None of the authors has any potential conflict of interest.
Human and animal right statement
We declare that all human and animal studies have been approved by — University and — Hospital and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.
We declare that all patients gave informed consent prior to inclusion in this study.
This study was funded by Shanghai Municipal Science and Technology Commission (Grant number: 16411964100, 2016) and the National Natural Science Foundation of China (Grant no. 81472036, 2015).
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