Synonyms
Contrast medium imaging of the spinal canal (syn. spinal canal).
Definition
A myelography is an invasive (bodily harming) diagnostic X-ray procedure for the clarification of back pain when there is a suspicion that the cause of the pain is related to a compression of the spinal cord (myelon) or spinal nerves and other modern imaging techniques, such as magnetic resonance imaging (MRI) of the back, are not sufficient to make the diagnosis. The principle of myelography is to show the space available for the spinal cord and spinal nerves by injecting an X-ray contrast medium into the spinal canal (subarachnoid space). Various diseases of the spinal column can give rise to the need for myelography.
What they all have in common is that nerve damage in the spinal canal is suspected. In most cases, these are diseases that are part of the general aging process (degenerative spinal diseases) of the spine, which are comparable to the signs of wear and tear of the major body joints (knee arthrosis, hip arthrosis). Bone attachments, intervertebral disc material and ligament structures in the spinal canal can lead to an increasing narrowing of the spinal canal (spinal canal stenosis).
To a certain degree of constriction, the nerve fibers get used to the confined space. At some point, however, the space is so cramped that pressure-induced nerve damage occurs, which is manifested as pain, weakness and sensation in the arms or legs. In other cases, isolated constriction in the area of one or more nerve root exit holes can also occur (neuroforaminal stenosis).
In this case, the spinal cord tube is not crowded as a whole, but only individual spinal cord nerve-spinal nerves. Depending on which spinal nerves are affected, there may be signs of back pain that is transmitted to the leg or arm (lumboischialgia, cervicobrachialgia). In all these cases, myelography can be of diagnostic help if, despite a magnetic resonance imaging (MRI) of the lumbar or cervical spine, there are still uncertainties. Myelography is often used to plan the extent of surgery in spinal operations (spondylodesis, decompression).
- Spinal cord
- Spinal canal stenosis
- Vertebral body
- Intervertebral disc
