The Role of CT Discography in Far Lateral Disk Herniation

ABSTRACT

PURPOSE: To evaluate the value and the radiologic findings of CT discography in the diagnosis of the far lateral disk herniation. MATERIALS AND METHODS: We retrospectively reviewed 7 cases of surgically proven far lateral lumbar disc herniation. CT discography was performed for all cases. Four cases underwent conventional CT and three cases MRI as a primary diagnostic imaging method. Far lateral diac herniation was divided into 3 groups by location;Intraforaminal herniation, extraforaminal herniation, and mixed type. We analyzed the findings of CT discography including location and extent of far lateral disc herniation. RESULTS: In all 7 cases, CT discography clearly demonstrated the filling of contrast media in laterally-protruded disc material. Intraforaminal and extraforminal types were seen in 2 cases each, and mixed type in 3 cases. Subligamentous herniated nucleus pulposus was present in 6 cases and extruded disc in 1 case. Far lateral disc herniation was located at L4-5 in 5 cases and L5-S1 in 2 cases. CONCLUSION: CT discography can help establishing accurate preoperative diagnosis for far lateral disc herniation.