Myelography uses a real-time form of x-ray called fluoroscopy and an injection of contrast material to evaluate the spinal cord, nerve roots and spinal lining. By injecting contrast material into the spine, doctors can visualize the spinal cord, nerves, and tissues that line the nerves (meninges). Myelography is typically used to evaluate the spine before and after surgery and to detect problems in patients who cannot undergo MRI.