[Diagnostic imaging following surgery of spinal disk herniation]

The magnetic resonance imaging findings recorded in patients after surgery for degenerative disc disease in the lumbar and cervical spine are discussed in comparison with conventional radiographs and computed tomography findings. In the lumbar spine normal postoperative findings in the immediate postoperative period can be demonstrated by MR imaging. Contrast-enhanced MR imaging can differentiate disc herniation from postoperative scar formation with a greater degree of confidence than other imaging modalities. MR imaging improves differentiation between other causes of failed back syndrome such as postoperative hematoma and infection, lateral spinal stenosis and arachnoiditis. In the cervical spine types of operative approaches, the appearance of bony stenosis and disc herniations by MR imaging are discussed. Computed tomography still has a role in the assessment of osseous complications such as central or foraminal stenosis.