Application Of Apparent Diffusion Coefficient In The Assessment Of Lumbar Disc Degeneration In Patients With Low Back Pain

Objectives To investigate the application value of apparent diffusion coefficient(ADC)in the evaluation of lumbar disc degeneration in patients with low back pain.Methods Sixty patients of spinal surgery outpatient of our hospital from February 2017 to May 2017 were enrolled in the study.Lumbar spine imaging of all enrolled patients was performed on a 3.0T magnetic resonance imaging scanner(GE,Signa HDxt,USA).Imaging included sagittal T1 weighted image(T1WI),T2 weighted image(T2WI)and diffusion-weighted images(DWI)with the b value of 600 s / mm2.All intervertebral discs were graded with Pfirrmann’s grading system on sagittal T2 WI,and the elliptic region of interest(ROIs),on the middle section of the sagittal DWI,was manually drawn on the nucleus pulposus of each lumbar disk,all the ADC values of each disc were calculated.Correlation analysis between Pfirrmann’s grading and ADC value of all intervertebral discs.Analyzing the correlations between visual analogue scales(VAS)and Pfirrmann’s grading,VAS and ADC values,to evaluate the correlation between the degree of low back pain and two measures.Subgroup analysis of the intervertebral discs was performed according to the body mass index(BMI),and to compare the differences of ADC values of different subgroups.Multiple linear regression analysis was used to investigate the relative influences of BMI and age upon the ADC values.Results A total of 300 intervertebral discs in the 60 patients were studied.According to the Pfirrmann’s grading system,the number of I to V in 300 discs was 35(11.7%),60(20%),87(29%),113(37.6%)and 5(1.7%).The ADC value exhibited a more significant negative correlation with Pfirrmann grades(r =-0.796,p <0.05).There was a obvious positive correlation between Pfirrmann’s grading and VAS(r=0.573,P<0.05),and there was a significant negative association between ADC values and VAS(r=-0.826,P<0.05).Multivariate regression analysis showed that BMI and age were influence factors of ADC values,and there was a significant negative correlation between factors and ADC values.Conclusion Pfirrmann’s grading was highly correlated with ADC values.The VAS was highly negative correlated with ADC values of the patients with low back pain,but lower correlation with Pfirrmann’s grading,and the ADC values can evaluate the lumbar disc degeneration in patients with low back pain better than Pfirrmann’s grading.The age and BMI were influence factors and The greater the age and BMI,the lower the ADC values.The ADC values can reflect the intervertebral disc degeneration in patients with low back pain sensitively,accurately and objectively,and it is valuable for diagnosis of degeneration discs.