ABSTRACT
Objective To evaluate the correlation between diffusion tensor imaging(DTI)measurements,fiber tracking(FT)and the clinical symptoms in patients with cervical spondylotic myelopathy.Methods According to the Japanese orthopaedics association score(JOA),104 patients with cervical spondylopathy were divided into 4 groups:mild in 31 patients with 13-16 scores,moderate in 27 with 9-12 scores,severe in 25 with 5-8 scores,and serious in 21 with 0-4 scores.According to the lesion signal characters,all patients were divided into 3 groups:Group A with normal signal in both T1 WI and T2WI in 33 patients,Group B with normal signal in T1WI but high signal in T2WI in 30 patients,and Group C with low signal in T1 WI and high signal in T2WI in 41 patients.Apparent diffusion coefficient (ADC),fractional anisotropy(FA),λ1,λ2,λ3 were measured in the spinal cord at the serious pressed section,and fiber tractography was performed.The Spearman correlation analyses was used to correlate each of the DTI measurement with JOA score.Group difference was tested with one-way ANOVA method.Results High quality of DTI was acquired in all patients.The FA values in the mild,moderate,severe,and serious groups were respectively 0.69 ±0.13,0.58 ±0.03,0.46 ±0.08,and 0.37 ±0.11 and significant difference was found in different groups(F =100.59,P ＜ 0.05)and positively correlated with JOA scores (r =0.883,P ＜ 0.05).There was no statistical significance between JOA scores and ADC,λ1,λ2,λ3(r=0.232,0.217,0.113,0.127,P ＞0.05).The FA values in group A,B,and C were respectively 0.67 ±0.33,0.51 ±0.21,0.38 ±0.03,and significant difference was found among different groups(F =50.05,P ＜ 0.05).Decrease of JOA score and high signal in T2 companied with decrease of FA value.Decrease of FA values was found associated with increase of fiber bundle damage.The ADC,λ2,λ3 but not λ1 were significantly different among the JOA groups and the group A,B,and C.Conclusions The FA values are positively correlated with clinical symptoms.Decrease of FA values is found associated with increase of fiber bundle damage.DTI can show the severity and extent of damage of spinal cord in patients with cervical spondylotic myelopathy.