How is tethered spinal cord syndrome diagnosed?
When tethered spinal cord syndrome is suspected in a newborn under 3 months old, the easiest and fastest way to confirm the diagnosis is with an ultrasound of the baby's back.
- uses high-frequency sound waves to take pictures of a part of the body
- doesn’t require the child to receive any sedation or anesthesia
- shows the spinal canal in great detail, since the bones in the baby's back are very thin at this age
- will usually also show where the end of the spinal cord is (if it is dropped down at a low level, tethering is likely)
- can show if the spinal cord is pulsating in a natural movement within the canal (if it is not moving, a tethering obstruction may be holding it taut)
- can reveal any tumors or fatty masses at the end of the spinal cord
Diagnosing infants and older children
Because the bones in an infant's back become thicker with age, ultrasounds are not usually helpful in diagnosing tethered spinal cord syndrome in children older than 3 months. In these children, the most effective diagnostic procedure is Magnetic Resonance Imaging (MRI).
- uses a combination of powerful magnets, radiofrequency waves and special computers to generate three-dimensional images of the spinal canal and its structures
- is not painful, but does require sedation to ensure the child stays still and in the proper position
- is usually not done until the child is between 3 and 6 months of age, when he is big enough to ensure more subtle changes in his anatomy can be detected by the MRI (and when the risks of anesthesia are lessened)
- can sometimes be recommended in babies under 3 months if symptoms of tethered spinal cord are significant and pronounced (for example, if a dimple or hair mass on the back is very deep, very large, inflamed or draining); in these babies, tests need to be conducted immediately to prevent an infection reaching the spinal canal or the onset of meningitis
Depending on your child's individual symptoms and circumstances, your treating clinician may also recommend other tests, such as:
- X-rays of the spine—x-rays, which use small doses of radiation to take pictures of a part of the body, are ordered only in special situations for a child with tethered cord (for example, to detect unusual changes in bone structure).
- Computed Tomography (CT) scans of the lower back—this type of imaging, which uses a combination of X-rays and powerful computers, is sometimes prescribed to give more detailed information about an abnormality in the anatomy of the child's spine. CT can be a useful tool in planning surgical procedures for some children.
- urodynamics testing—since the nerves in the bladder are linked to the nerve cells at the bottom of the spinal cord, many children have problems with bladder control. Urodynamics studies measure how well the nerve supply from the child's spinal cord to his bladder is working. In addition to confirming nerve damage caused by tethered cord, these tests can also help clinicians plan surgical procedures and anticipate (and help families manage) future problems with incontinence.