Clinical Application Of Magnetic Resonance Diffusion Tensor Imaging In Lumbosacral Nerves

Objective1、To investigate the feasibility of DTI and DTT on lumbosacralnerves.2、Magnetic resonance diffusion tensor imaging was performed on20healthy volunteers.3D images of the nerves(L4， L5， S1) werereconstructed on DTT； FA (Fractional anisotropy)、 ADC (Apparentdiffusion coefficient) of the nerves were measured. To obtain the diffusionparameters of the normal person and evaluate the quality of the nerveimage on DTI and DTT.3、Magnetic resonance diffusion tensor imaging was performed on16patients with LDH，3D images of the oppressed nerves were reconstructedon DTT. FA (Fractional anisotropy) and ADC (Apparent diffusioncoefficient) of the nerve roots(L4，L5，S1) were measured and comparedwith the normal diffusion parameters of the healthy volunteers. To evaluatethe clinical application of DTI and DTT for lumbosacral nerve diseases.Methods1、Magnetic resonance diffusion tensor imaging was performed on20 healthy volunteers at Philips Achieva3.0T MR scanner(T1WI，TR=453ms,TE=8.0ms, FOV(AP=300mm,FH=261mm,RL=52mm), Matrix=248×258,=12,=4mm;T2WI,TR=2000ms,TE=100ms,FOV(AP=300mm,FH=261mm,RL=52mm), Matrix=224×224, Gap=12, Thick=4mm; DTI, TR=3498ms,TE=50ms; b=800s/mm2; Matrix=96×99; Thick=1.5mm). FA (Fractionalanisotropy) and ADC (Apparent diffusion coefficient) of the nerve roots (L4,L5, S1) were measured and the results of DTI and DTT were obtained.2、Magnetic resonance diffusion tensor imaging was performed on16patients. FA and ADC of the oppressed nerve roots(L4，L5，S1) weremeasured, DTI and DTT results were obtained.16patients received surgeryin our department，and2patients’ FA and ADC values were followed up3days and2weeks after the surgery, which compared with the preoperativevalues.Results1、20volunteers were successful reconstructed by DTI and DTT. L4,L5, S1nerves could show clearly on the DTT map. The average ADC andFA values of healthy volunteers (L4, L5, S1) were0.395±0.146and1.288±0.116mm2/s,0.390±0.122and1.297±0.087mm2/s,0.387±0.117and1.294±0.132mm2/s, respectively. There was no significant difference ofdiffusion tensor parameters between bilateral nerves (P>0.05), and therewas no significant difference of diffusion tensor parameters between upperand lower nerves (P>0.05). 2、The average ADC and FA values of patients were0.217±0.105and(1.514±0.275) mm2/s、0.234±0.213and (1.671±0.310)mm2/s、0.250±0.166and (1.573±0.144)mm2/s, respectively. FA and ADC values weresignificantly different between healthy volunteers and patients with LDH(P <0.05for both FA and ADC). The FA and ADC values were followedup3days and2weeks after the surgery, there were significantly differentbetween pre-operation and post-operation.Conclusion1、DTI and DTT on lumbosacral nerve of normal adults are feasible.2、DTI and DTT can show the architecture of the nerves and conductquantitative analysis for further research of the nerve root diseases.3、FA and ADC values of oppressed nerve roots was significantlyaltered in both pre-operation and post-operation, but their importance stillneeds further research because a lack of the pathologic evidences.