Correlation of plain radiography and MRI spine evaluation in spinal TB

Abstract

Background: Both x-ray and MRI play a pivotal role in the diagnosis of tuberculous spondylodiscitis. However x-ray has disadvantages of not detecting cord changes and disc space changes however MRI is an expensive modality of investigations. The purpose of this study is to correlate the plain radiograph and MRI spine in evaluation spinal TB. Methods and Materials:The present cross sectional study was conducted on patients with clinical suspicion of spinal tuberculosis of who will be referred to radiology department for MRI. The imaging was be done using Allengers Digital Radiography machine and SIEMENS 1.5 tesla MR scanner using spine coil. Routine imaging sequences were done. Diagnosis was confirmed with clinical and laboratory parameters. Initially AP and Lateral spine bucky radiograph will be taken in the 500mA X-Ray machine. Then non contrast T1 weighted (T1W), T2 weighted (T2W) and short tau inversion recovery (STIR) sequences in axial, sagittal and coronal planes of the involved spine were taken. Result: In the present study, the subjects were categorized into three age groups with an interval of 10. The above table gives data on distribution of study subjects based on their age. More subjects were found in the age group of 31-40 years, i.e., 21 subjects (60%); followed by 10 subjects in the age group of 41-50 years (28.57%); 4 subjects in the age group of 21-30 years (11.43%). Majority were males, i.e., 23 (65.71%) followed by 12 females, (34.29%). Majority subjects were residing in rural areas, i.e., 20 subjects (57.14%) followed by 15 subjects residing in urban areas (42.86%). Majority subjects were experiencing symptoms for 6 to 10 months, i.e., 22 subjects (62.86%); followed by 8 subjects for < 6 months (22.86%) and finally 5 subjects experiencing symptoms for > 10 months (14.29%). The mean calculated was 9.95±4.71The frequency of paravertebral widening on plain radiography was 8 (22.85%) and that on MRI was 19 (54.29%). The difference in the percentage was 31.44. The frequency of posterior element involvement on plain radiography was 6 (17.14%) and that on MRI was 13 (37.14%). The difference in the percentage was 20. The frequency of vertebral height reduction on plain radiography was 5 (14.28%) and that on MRI was 11 (31.42%). The difference in the percentage was 17.14. The frequency of thecal sac compression, cord compression and cord changes were not found on plain radiography. Their frequencies on MRI were 5 (14.28%). The difference in the percentage was 14.28. Conclusion: MRI is a better and more informative imaging modality in evaluation of patients of Pott's spine, however, both X-rays and MRI have their own diagnostic importance, advantages and disadvantages and both are complementary to each other for evaluation of tuberculosis of spine.