Study Of 3.0T MR Diffusion Tensor Imaging In Cervical Spondylotic Myelopathy

Part ? Study of 3.0-T MR diffusion tensor imaging of cervical spinal cord in normal adult populationObjectivesTo determine the normal reference value of fractional anisotropy(FA)and apparent diffusion coefficient(ADC)of the cervical spinal cord in healthy adults.To compare the differences of FA and ADC among the different levels of cervical spinal cord and different age groups,and investigate the correlation of FA value,ADC value with ageMaterials and MethodConventional MRI and DTI sequences scanning were performed on 50 healthy adults using 3.0T MR.Based on the level of intervertebral space,50 volunteers were divided into six groups(C1-2?C2-3?C3-4?C4-5?C5-6?C6-7).According to ages,all volunteers were divided into three groups(young group,middle-aged group and old group).The apparent diffusion coefficient(ADC),fractional anisotropy(FA)were measured,and the differences of the parameter values among the different groups was compared.Then we calculated the correlation of FA value,ADC value with age.Diffusion tensor tractography(DTT)was performed on the cervical spinal cord and its morphological characteristics were observed Results1.There was no significant difference in FA and ADC values at different cervical spinal cord levels(P>0.05);2.There were significant differences in FA and ADC values among three age groups(P<0.05);3.The normal cervical spinal cord FA value was negatively correlated with ADC value(r=-0.468,P<0.001);4.The FA value of cervical spinal cord was negatively correlated with age(r=-0.745,P<0.001),while the ADC value was positively correlated with age(r=0.618,P<0.001).Conclusion1.It was feasible to use the 3.0T MR and RESOLVE sequence to perform sagittal DTI imaging of the cervical spinal cord;2.DTI was more sensitive in detecting the changes of cervical spinal cord micro structures than conventional MRI and can be used for quantitative analysis.FA and ADC were the two most commonly used quantitative parameter values.DTT can simulate the structure of fibrous bundles in space;3.There was no significant difference in FA and ADC values at different cervical spinal cord levels,but age is an important factor affecting the FA and ADC values of normal cervical spinal cord.Part ? Correlation study of 3T-MR-DTI quantitative analysis and clinical symptoms of cervical spondylotic myelopathyObjectivesTo investigate the clinical value of diffusion tensor imaging(DTI)in the diagnosis of cervical spondylotic myelopathy.Materials and MethodConventional MRI and DTI examination were performed on 55 patients with cervical spondylotic myelopathy using 3.0T MR.Based on the Japanese Orthopedics Association(mJOA)score,55 patients with CSM were divided into three groups(mild,moderate,and severe groups).At the same time,36 healthy volunteers matched by age and sex were selected from Part Ias control group.The FA and ADC values were measured at the maximum compression level of cervical spinal cord or at high signal sites on T2WI,and the correlation between FA,ADC and the clinical symptoms of CSM was explored.Diffusion tensor tractography was performed in the seriously compressed section of the spinal cord.Results1.The FA values and ADC values were significantly different among control group and three mJOA groups(P<0.001);2.The FA values were positively correlated with JOA scores(r=0.911,P<0.001),and ADC values were negatively correlated with mJOA score(r=-0.719,P<0.001);3.DTT showed that white matter fiber bundles were compressed,sparse and interrupted at the compression site of cervical spinal cord,and the damage of fiber bundles was aggravated with the progress of clinical symptoms.ConclusionDTI has important clinical value in diagnosis and quantitative evaluation of cervical spinal cord injury in cervical spondylotic myelopathy.FA value has a significant positive correlation with clinical symptoms and was a potential radiological indicator.