Values of CT-guided discography in diagnosing intervertebral disc pain

Objective:To discuss the values of CT-guided discography in diagnosing intervertebral disc pain. Methods: CT-guided discography was performed in 55 cases of the suspicious intervertebral disc pain, the positive discs were classified according to Dallas Discogram Description(DDD), then diagnosed definitely positive discs and the degree of degeneration and rupture of corresponding annulus fibrosus. Result: Thirty-three cases were positive by CT-guided discography, the positive rate in the elder group(50 year) was 35.7%, that in the younger group was 68.3%. To evaluate the degree and level of disc degeneration and rupture according to DDD, 1, 2, 3 degree of disc degeneration was 26.3%, 34.2%, 39.5% respectively; 1, 2, 3 degree of disc rupture was 23.7%, 73.7%, 2.6% respectively. Degenerative changes on MR image existed in all positive discs. 10 cases were positive in 11 cases existing HIZ on MR, the positive rate of which was 90.9%. Conclusion: ①The positive rate of discography was higher in the younger group of chronic lumbar pain. ②Abnormal morphology of discography(rupture within annulus fibrosus) was the basis of the positive inducing pain. ③It had high sensitivity but low specificity to diagnose intervertebral disc pain by MR, so we have to utilize discography to identify the responsible disc. ④HIZ on MRI has higher specificity to diagnose intervertebral disc pain. ⑤Diffuse factor of contrast media within intervertebral disc.