Dual energy CT myelography after lumbar osteosynthesis.

PURPOSE: The purpose of this study was to evaluate the benefits of CT myelography in the DE technique in patients with lumbar osteosynthesis.

MATERIALS AND

METHODS

In 30 patients a DE-CT scan of the spine with tube voltages of 80 kV and 140 kV was performed and a virtual monochromatic series of 120 kV was generated after intrathecal contrast injection. The impact of metal artifacts on the spinal canal and the spinal foramina was evaluated. The visualization of nerve roots was compared between a VRT series of the dural sac and conventional myelography.

RESULTS

With tube voltages of 140 kV, the artifacts were least pronounced. As no overlay disturbance was present, VRT visualization of the nerve roots was more reliable than conventional myelography.

CONCLUSION

In patients after osteosynthesis, CT in the DE technique provides minimal artifact disturbance using a tube voltage of 140 kV. "Virtual myelography" seems to be superior to conventional myelography for the evaluation of nerve roots. This could reduce additional conventional radiography, may shorten the entire examination and radiation time and diminish unnecessary painful movements for the patient.