A study of CT scan combined with dermatomal somatosensory evoked potential in the evaluation of lumbosacral disc herniation

Objective: To study the CT finding and dermatomal somatosensory evoked potential (DSEP) in pre-operative diagnosis of lumbosacral disc hemiation (LDH). Methods: Pre-operative CT scan and DSEP (L5 and S1) were performed in 72 patients with LDH. All the cases were proved by surgical operation. Results: In comparison with surgical findings, the accuracy rate of diagnosis using CT scan or DSEP was 88.9% and 91.7% respectively, while the accuracy rate approached 100% when an integrated consideration was made on both CT findings and the results of DSEP. Conclusion: There are advantages and disadvantages on CT scan and DSEP in evaluation of LDH. CT imaging demonstrates the morphological alternations of the lesions, while DSEP reveals the level and severity of the damage of function of the nerve roots. Comprehensive and accurate information is indicated when both methods are integrated, which helps the diagnosis and management of LDH. (authors)