3T MR Lumbar Sacral Nerve Root Imaging In Showing Correlation Of Lumbar Disc Herniation Position With Nerve Root Compression And Clinical Signs

Objective:To explore the correlation between position of lumbar disc herniation with compression of nerve root and clinical signs by 3.0T magnetic resonance imaging and to improve the diagnostic accuracy of lumbar disc herniation and the degree of injury of lumbar sacral nerve root. To provide direct basis for plan of operation and clinical prognosis.Materials and methods:87 patients with lumbar disc herniation who were treated with intervertebral disc removal were selected as symptom group, and 20 patients without lumbar disc herniation and neurological symptoms were selected as contrast group. Siemens Trio Tim 3.0T magnetic resonance scanner and TIM phase control coil image acquisitionwas used.87 patients in symptom group and 20 patients in contrast group were underwent preoperative lumbar conventional MR and 3D SPACE STIR,3D SPACE STIR contrast and DTI examination. All patients were informed consent before the examination. SIEMENS workstation with the 3D data analysis software and Neuro 3D processing was used in image post-processing, and part of the measurement with LANDWIND PACS image workstation. All statistical analysis was processed with 17 SPSS statistical software for Windows. T test was applied in quantitative data. P value less than 0.05 was considered having statistical difference.Results:In 87 cases of lumbar disc herniation patients, L4/5, L5/S1 disc herniation was accounted for 85.42%.78 cases had 1 segment of lumbar intervertebral disc protrusion, and 9 cases with 2 segment of lumbar disc herniation. L5 and S1 nerve root compression were the most compressed nerve roots, and the rate was 50.42% and 30.76%, respectively. To show lumbar disc herniation in transverse image of MRI, the position area 4th was accounted for the least proportion, about 13.79%. The proportion of remaining three areas had no statistical difference. But in the actual measurement of intervertebral disc herniation, protruding disc accounted for only one partition space was fewer. The protruding disc especially in 1 division and 2 division often accounted for two area, and protruding disc in 3th area was mostly accounted for more than two space, only protruding disc in 4 area had one region occupied. In the type of relationship between protruding disc with nerve root position in lumbar disc herniation patients, shoulder type was the most,52 nerve roots,44.44%. The anrerior shoulder type was in the second,27 nerve roots,23.08%. The next was armpit type 26 nerve roots,22.22%. The extreme lateral type was the least,10.26%, and this type was easily missed diagnosis. In opration findings of 87 cases of the patients with lumbar disc herniation, compression of the L4 nerve root in shoulder type was the most, and armpit type at least. For compression of the L5 nerve root, the shoulder type was the most, and armpit type at least. For compression of the S1 nerve root, armpit type was in the most, and extreme lateral at least. In lumbar routine MR examination, the degree of lumbar nerve root symptoms in lumbar disc herniation was gradually reduce from lth to 4th area. If intervertebral disc protrusion in lth area was larger than 5.2mm,2th area 4mm,3th area 2.9mm,4th area 1.2mm, it is need to pay further attention to determine whether there is the nerve root compression. The same segment of the lumbar intervertebral disc in different areas might cause different clinical signs.3D SPACE STIR sequence had obvious advantages compared with routine lumbar MR examination (P<0.05). In clinical signs with diagnosis of L4 nerve root comprassion, diagnosis coincidence rate of routine MR sequence was 77.27% and 3D SPACE STIR was 95.45%. In clinical symptoms of L5 nerve root routine comprassion, diagnosis coincidence rate of routine MR examination was 79.66%, and 3D SPACE STIR was 94.92%. In clinical symptoms of S1 nerve root routine comprassion, diagnosis coincidence rate of routine MR examination was 86.11%, and 3D SPACE STIR was 97.22%. DTI data measurement results showed that the FA value of the compressed nerve roots correlation with clinical signs was lower than that of normal volunteers (P<0.05), and ADC value was higher than the normal volunteers (P<0.05). FA values of compressed nerve root in lumbar disc herniation associated with clinical signs were lower than compressed nerve root in lumbar disc herniation unassociated with clinical signs (P<0.05), and the ADC values were higher (P<0.05).Conclusion:The diagnostic accuracy of 3D SPACE STIR in the intervertebral disc herniation was higher than that of conventional MR examination.3D SPACE STIR could show location of lumbar disc herniation, the compressed nerve root and injury degree of the nerve root. The correlation between lumbar disc herniation with clinical signs could be evaluated. An objective basis for the choice of treatment method was provided.3D SPACE STIR can show the variation of nerve root to avoid injury of nerve root in minimally invasive operation.3D SPACE STIR could display the intervertebral disc protrusion position and nerve root compression in three-dimension. Clinical signs of the patients are closely related with the situation of nerve roots compression. There was correlation between clinical signs of lumbosacral nerve root compression with DTI parameters. The combined application of MRI multiple sequences can analysis lumbar disc herniation and location of nerve root compression from multiple angles, and quantitative analysis could be done in correlation among lumbar disc herniation location, nerve root compression and clinical signs. A more direct basis for diagnosis and treatment of lumber disc herniation could be provided.