The research of diffusion tensor imaging of magnetic resonance imaging in normal cauda equina

Objective To explore the demonstration of the cauda equina(CE) and lumbosacral spinal nerve roots(LSNR) using diffusion tensor imaging(DTI) of magnetic resonance imaging(MRI) and measure the values of fractional anisotropy(FA) and average diffusion coefficient(DCavg) of CE and LSNR.Methods For 9 healthy young volunteers,T2WI and DTI were preformed from the upper middle level of the lumbar 2 and inferior margin of sacral 1 in axial direction in the slice thickness of 3 mm and without interslice gap.The CE and LSNR from lumbar 2 to sacral 1 were reconstructed and the values of FA and DCavg of the CE and LSNR were measured at the sites of each intervertebral foramen.Results From lumbar 2 to sacral 1,the CE had a good display.The LSNR were visualized in 60 bundles(83%).The values of FA and DCavg of CE were 0.359±0.068 and(3.711±0.595)×10-9 mm2/s and the values of FA and DCavg of LSNR were 0.322±0.040 and(3.753±0.647)×10-9 mm2/s individually.Based on Student's t-test,the values of FA had significant difference between the CE and LSNR,P0.001.The values of DCavg had no significant difference between CE and LSNR,P0.05.Conclusion DTI provides a non-invasive method to display the CE.Through the measurement of FA and DCavg in normal CE and LSNR,the insight has been promoted to the level of the changes of water molecular in assessing CE and LSNR.